NLE Hematologic Nursing — Hematologic Assessment and the AnemiasStudy Notes

The hematologic system comprises blood (plasma and formed elements) produced in the bone marrow through a continuous process called hematopoiesis. Blood serves three critical functions: (1) oxygen delivery via hemoglobin in erythrocytes, (2) immune defense through leukocytes, and (3) hemostasis (clotting) through platelets and clotting factors. Understanding the origin and lifespan of each blood cell helps you anticipate clinical problems and recognize compensation mechanisms in disease. The bone marrow produces approximately 200 billion cells daily in a healthy adult, and any disruption to this process manifests clinically. Erythrocytes (red blood cells) carry hemoglobin, an iron-containing protein that reversibly binds oxygen. RBCs survive approximately 120 days in circulation before being destroyed in the spleen. Their production is regulated by erythropoietin (EPO), a hormone released by the kidneys in response to tissue hypoxia. This feedback mechanism is vital: when oxygen levels drop, kidneys sense this and increase EPO secretion, stimulating bone marrow to produce more RBCs. Conversely, adequate oxygenation suppresses EPO. Leukocytes (white blood cells) comprise five types: neutrophils (most numerous, first-line bacterial defense), lymphocytes (immune memory and antibody production), monocytes (tissue macrophages), eosinophils (parasite defense), and basophils (allergic responses). When infection occurs, the bone marrow receives signals to increase neutrophil production, often releasing immature forms (bands) into circulation—a phenomenon called a "left shift" that signals acute infection. Thrombocytes (platelets) are not cells but cell fragments; they initiate the clotting cascade by adhering to vessel walls and aggregating. Normal platelet survival is 7–10 days. The spleen filters aged RBCs and stores approximately 30% of the body's platelet pool; liver damage or splenomegaly can disrupt this balance. The spleen also stores iron, vitamin B12, and folate—nutrients essential for normal hematopoiesis. The liver produces most coagulation factors (prothrombin, fibrinogen) and stores intrinsic factor is absorbed in the terminal ileum, so any damage to this organ (from cirrhosis, alcoholism) compromises hematologic function. These organ-system interdependencies are critical for nurses working in Philippine hospitals managing patients with chronic liver disease or splenic disorders.

Systematic hematologic assessment requires a focused health history and thorough physical examination. Using the nursing process framework aligned with RA 9173, you gather subjective and objective data to formulate nursing diagnoses and guide interventions. HEALTH HISTORY: Begin by exploring presenting symptoms. Ask about fatigue and weakness (cardinal signs of anemia—tissue hypoxia reduces energy production). Inquire about dyspnea, especially on exertion (indicates inadequate oxygen-carrying capacity). Ask about dizziness, headaches, or chest discomfort (compensatory tachycardia and increased cardiac workload). Explore bleeding or bruising: epistaxis, gum bleeding, heavy menstrual periods, blood in stools or urine (suggests thrombocytopenia or coagulation defect). Ask about recurrent infections (neutropenia) and fever patterns. Dietary history is crucial: assess iron intake (red meat, leafy greens, legumes common in Filipino diet like mongo beans), vitamin B12 sources (meat, dairy—important in vegan patients), and folate (vegetables, citrus). In the Philippine context, inquire about malnourishment, which is endemic in rural areas and contributes to anemias. Medication history: anticoagulants (warfarin, apixaban), antiplatelet agents (aspirin), NSAIDs (can cause GI blood loss), chemotherapy (bone marrow suppression), and antibiotics like chloramphenicol (rare in modern practice but historically associated with aplasia). Family history: note sickle cell disease, thalassemia, hemophilia, or other hereditary anemias—important in patients with African, Mediterranean, or Southeast Asian ancestry. PHYSICAL EXAMINATION: Inspection of skin and mucous membranes: Pallor is a key sign of anemia. Assess the conjunctivae, inner lower eyelid, nail beds, and palms—these areas with less melanin are most reliable for detecting pallor in darker-skinned patients (a critical point for Filipino nurses assessing patients across diverse skin tones). Jaundice (yellowing of sclera and skin) suggests hemolysis (RBC breakdown) or liver disease. Cyanosis (bluish tint) indicates hypoxemia. Look for petechiae (pinpoint red spots) and purpura (larger purple patches) on lower extremities and dependent areas—hallmarks of thrombocytopenia. Observe for ecchymoses (bruising) from minor trauma. Examination of oral cavity and tongue: Glossitis (inflamed tongue with loss of papillae, appearing beefy red and sore) occurs in B12 and iron deficiency. Angular cheilitis (cracks at corners of mouth) indicates B12 or iron deficiency. Spoon-shaped nails (koilonychia) are pathognomonic for iron deficiency anemia. Cardiovascular assessment: In anemia, cardiac output increases to compensate for reduced oxygen-carrying capacity. Listen for tachycardia at rest and a systolic flow murmur (from increased flow velocity across the aortic valve). These are compensatory mechanisms; you'll often see respiratory rates also elevated (tachypnea). Neurologic examination: Vitamin B12 deficiency causes demyelination. Assess for paresthesias (tingling) in hands and feet, impaired proprioception (lose position sense), ataxia (unsteady gait), and hyperreflexia. These neurologic signs are absent in folate deficiency, a key differential. If untreated, B12 deficiency causes irreversible spinal cord damage and cognitive changes. Abdominal examination: Palpate for splenomegaly (enlarged spleen in hemolysis, malignancy, or bone marrow disorders) and lymphadenopathy (infection, malignancy). In hemolytic anemia, the spleen is often enlarged from constant RBC destruction and filtering. Assess for signs of bleeding: gum bleeding on gentle brushing, bleeding from IV sites, oozing from any wound. In severe thrombocytopenia, spontaneous bleeding may occur.

The CBC is the cornerstone laboratory test for hematologic assessment. It provides quantitative and qualitative information about RBCs, WBCs, and platelets. Mastering CBC interpretation is essential for NLE success and safe clinical practice. NORMAL REFERENCE VALUES FOR ADULTS: Hemoglobin (Hgb): Male 13–18 g/dL; Female 12–16 g/dL. Hemoglobin represents the oxygen-carrying capacity of blood. A Hgb below normal ranges indicates anemia; above normal indicates polycythemia. Hematocrit (Hct): Male 42–52%; Female 37–47%. Hematocrit is the percentage of blood volume occupied by RBCs. Roughly, Hct is approximately 3 times the Hgb value (e.g., Hgb 13 g/dL corresponds to Hct ~39%). Both reflect the same phenomenon—RBC mass. RBC count: 4.2–6.1 million/µL (or 4.2–6.1 × 10^12/L). This absolute count of circulating RBCs; very sensitive but provides less clinical detail than Hgb/Hct. WBC count: 5,000–10,000/µL (or 5.0–10.0 × 10^9/L). The total count of circulating white cells. Elevated (>10,000) is leukocytosis, indicating infection, inflammation, leukemia, or stress. Decreased (<5,000) is leukopenia, suggesting bone marrow failure, medication effect, or immune destruction. Platelets: 150,000–400,000/µL (or 150–400 × 10^9/L). Critical for hemostasis. Below 150,000 is thrombocytopenia; risk of spontaneous bleeding increases sharply below 50,000. Above 400,000 is thrombocytosis, increasing clotting risk. Mean Cell Volume (MCV): 80–100 femtoliters (fL). MCV indicates RBC size and is the key to classifying anemia: - **Microcytic (MCV < 80 fL)**: small RBCs → iron deficiency anemia, thalassemia, anemia of chronic disease - **Normocytic (MCV 80–100 fL)**: normal-sized RBCs → acute blood loss, hemolytic anemia, aplastic anemia - **Macrocytic (MCV > 100 fL)**: large RBCs → vitamin B12 deficiency, folate deficiency, alcoholism Mean Corpuscular Hemoglobin Concentration (MCHC): 32–36 g/dL. Indicates hemoglobin concentration within RBCs. Low MCHC indicates hypochromia (pale cells, typical in iron deficiency). Reticulocyte count: 0.5–2.0% of RBCs (or 24,000–84,000/µL). Reticulocytes are immature RBCs still containing ribosomes; they mature within 1–2 days in circulation. The reticulocyte count reflects bone marrow's ability to produce RBCs in response to demand: - **High reticulocyte count** (>2%): appropriate marrow response to blood loss or hemolysis. The marrow is "working hard" to replace lost cells. - **Low reticulocyte count** (<0.5%): indicates marrow failure (aplastic anemia, leukemia) or nutritional deficiency (iron, B12, folate) where the stimulus to produce RBCs is inadequate. WBC Differential: Breaks down WBCs into neutrophils (60–70%), lymphocytes (20–30%), monocytes (3–8%), eosinophils (<4%), and basophils (<1%). Interpretation in context of total WBC is critical: - **Absolute neutrophil count (ANC) = Total WBC × % neutrophils** (reported in many labs). ANC indicates infection-fighting capacity: - ANC > 1,500/µL: normal - ANC 1,000–1,500/µL: mild neutropenia - ANC 500–1,000/µL: moderate neutropenia; increased infection risk - **ANC < 500/µL: severe neutropenia**; high risk of serious infection; requires protective isolation and aggressive infection prevention - **Left shift**: increased number of immature neutrophil forms (bands, metamyelocytes) indicates acute infection or leukemia. The marrow is releasing cells before they mature. - **Right shift**: increased number of hypersegmented neutrophils (>5 lobes) suggests B12 or folate deficiency. Peripheral Blood Smear: Microscopic examination of blood cells reveals morphology not captured by numbers alone: - Target cells: may indicate liver disease or hemoglobin C disease - Schistocytes (fragmented RBCs): mechanical hemolysis, disseminated intravascular coagulation (DIC) - Sickle cells: sickle cell disease - Blasts: leukemia - Spherocytes: hereditary spherocytosis or immune hemolysis - Hypochromic, microcytic RBCs: iron deficiency INTERPRETATION ALGORITHM: 1. Is the patient anemic? (Hgb/Hct below reference range?) 2. If yes, what is the RBC morphology? (Use MCV: micro-, normo-, or macrocytic?) 3. What is the reticulocyte count? (High = appropriate response; low = marrow failure or deficiency) 4. Are WBCs and platelets normal? (Pancytopenia suggests marrow disease) 5. Review the smear for specific cell forms (targets, sickles, blasts, etc.) CLINICAL CORRELATIONS: A Hgb of 10.5 g/dL with MCV 68 fL and low reticulocyte count points to iron deficiency. The low MCV (microcytic) narrows the differential. The low reticulocyte count indicates insufficient marrow response—typical when the body lacks the iron substrate to make hemoglobin. A Hgb of 11 g/dL with MCV 115 fL, hypersegmented neutrophils, and positive Schilling test points to pernicious anemia. The high MCV (macrocytic) and neurologic symptoms (if present) differentiate this from folate deficiency. A WBC of 2,500/µL with ANC of 1,200/µL, Hgb 9 g/dL, and platelets 80,000 in a patient on chemotherapy raises concern for bone marrow suppression (pancytopenia). Implement neutropenia precautions and bleeding precautions.

Blood transfusion is a common life-saving intervention in Philippine hospitals. Understanding blood groups, compatibility, and transfusion reactions is essential for safe nursing practice under RA 9173. ABO BLOOD GROUP SYSTEM: The ABO system is based on the presence or absence of A and B antigens on the RBC membrane. These antigens are glycoproteins; individuals develop antibodies (agglutinins) in plasma against antigens they lack—a natural immunity that arises early in life. Type A: Has A antigens on RBCs; has anti-B antibodies in plasma. Can receive from: A and O. Can donate to: A and AB. Type B: Has B antigens on RBCs; has anti-A antibodies in plasma. Can receive from: B and O. Can donate to: B and AB. Type AB: Has both A and B antigens on RBCs; has NO ABO antibodies in plasma (universal recipient). Can receive from: A, B, AB, and O (all types). Can donate to: AB only. Type O: Has NO A or B antigens on RBCs; has both anti-A and anti-B antibodies in plasma (universal donor). Can receive from: O only. Can donate to: A, B, AB, and O (all types). TRANSFUSION COMPATIBILITY: **Type O-negative blood is the universal donor**. It lacks A, B, and Rh(D) antigens, so it cannot trigger an ABO or Rh reaction in any recipient. In emergency departments throughout the Philippines, type O-negative is the default when blood type is unknown and time is critical (massive transfusion protocols, trauma, obstetric hemorrhage). **Type AB-positive is the universal recipient**. It has A and B antigens (so the recipient's RBCs won't be attacked by donor anti-A or anti-B antibodies) and is Rh-positive (won't develop anti-D antibodies). These patients can safely receive any ABO/Rh combination. RH (D) ANTIGEN SYSTEM: About 85% of the Philippine population is Rh-positive (has D antigen on RBCs); 15% is Rh-negative (lacks D antigen). Unlike ABO, individuals are NOT born with anti-D antibodies. However, Rh-negative individuals develop anti-D antibodies (sensitization) after exposure to Rh-positive blood. This has critical implications: - **First transfusion**: Rh-negative patient given Rh-positive blood typically has no immediate reaction (no pre-existing anti-D), but becomes sensitized. Subsequent transfusions with Rh-positive blood may trigger hemolytic transfusion reaction. - **Pregnancy**: An Rh-negative mother carrying an Rh-positive fetus may become sensitized if fetal RBCs enter maternal circulation (fetomaternal hemorrhage), especially during delivery. Maternal anti-D antibodies cross the placenta and attack fetal RBCs, causing hemolytic disease of the newborn (erythroblastosis fetalis). This is prevented by giving **RhoGAM (anti-D immunoglobulin)** to Rh-negative mothers at 28 weeks gestation and within 72 hours of delivery of an Rh-positive infant. TYPE AND CROSSMATCH: Before transfusion, two steps ensure compatibility: **Type and Screen**: ABO/Rh type is determined on the patient's blood. Serum is screened for unexpected antibodies (indirect antiglobulin test or indirect Coombs). This takes ~5–10 minutes and is acceptable for elective transfusions. **Type and Crossmatch**: Beyond typing, donor RBCs are incubated with patient serum and checked for hemolysis or agglutination, confirming no incompatible antibody-antigen reaction. This takes ~30–45 minutes but provides the highest safety assurance. In emergencies (life-threatening hemorrhage), type O-negative is given without waiting for crossmatch. COOMBS TEST (ANTIGLOBULIN TEST): Two versions detect antibodies involved in hemolytic reactions: **Direct Coombs**: Detects antibodies already bound to the patient's RBCs. A positive direct Coombs indicates immune hemolysis (warm autoimmune hemolytic anemia, hemolytic transfusion reaction, hemolytic disease of the newborn). **Indirect Coombs**: Detects free antibodies in the patient's serum (not bound to RBCs). Used to screen for unexpected antibodies before transfusion and to detect sensitization (e.g., Rh-negative mother after delivery of Rh-positive infant). TRANSFUSION REACTIONS: Acute hemolytic transfusion reaction (ABO incompatibility) occurs within minutes of starting transfusion. Symptoms include fever, chills, back or flank pain, dark urine (hemoglobinuria), dyspnea, and hypotension. Immediate action: stop transfusion, keep IV patent with normal saline, notify physician, recheck type/crossmatch, send patient blood and donor blood for serologic testing, send urine sample (check for hemoglobin). Nursing care focuses on preventing renal failure (aggressive hydration, monitor urine output and color) and managing shock. Febrile nonhemolytic transfusion reaction: fever without hemolysis, often from WBC antigens in stored blood. Manage with acetaminophen and continue transfusion at slower rate if medically necessary. Allergic reaction: urticaria, itching; may progress to anaphylaxis. Stop transfusion, give antihistamines; restart if reaction mild. Severe anaphylaxis requires epinephrine and ICU care. TRansfusion-related acute lung injury (TRALI): dyspnea, hypoxemia, pulmonary edema within 2–6 hours of transfusion. Stop transfusion, manage as respiratory emergency.

Iron-deficiency anemia is the most common anemia worldwide and a frequent diagnosis in Philippine primary care, particularly among women of reproductive age and young children. It results from depletion of iron stores, leading to insufficient hemoglobin synthesis and small, pale RBCs (microcytic, hypochromic anemia). PATHOPHYSIOLOGY: Iron is essential for hemoglobin synthesis; it is also found in myoglobin (muscle oxygen storage) and cytochromes (cellular respiration). The body contains about 3–4 grams of iron: 70% in hemoglobin, 20% in iron stores (ferritin in liver, spleen, bone marrow), and 10% in myoglobin and enzymes. Iron is recycled: when RBCs are destroyed after 120 days, iron is reclaimed by macrophages and reused—so minimal iron loss occurs daily (only ~1–2 mg from skin cells, GI shedding, and menstruation). However, when iron loss exceeds intake or absorption, stores gradually deplete. Initially, stored iron compensates, but once stores are exhausted, serum iron falls, hemoglobin synthesis slows, and RBCs become smaller and paler. CAUSES: **Chronic blood loss** (most common cause in adults): GI bleeding (peptic ulcer, gastritis, colon polyp, colorectal cancer), heavy menstrual bleeding (most common cause in reproductive-age women in the Philippines), hematuria (urinary tract disease). **Inadequate dietary intake**: Vegetarian or vegan diets lacking heme iron (from meat; better absorbed than nonheme iron from plants); poverty-related malnutrition common in rural Philippine populations. **Malabsorption**: Celiac disease, H. pylori infection (impairs gastric acid needed for iron absorption), gastrectomy (surgical loss of acid-secreting mucosa), antacid overuse. **Increased demand**: Pregnancy (expanded blood volume, fetal needs), infancy and childhood (rapid growth), adolescence (menstruation plus growth). LABORATORY FINDINGS: **CBC**: - Low hemoglobin and hematocrit - **Low MCV (<80 fL)**: microcytic RBCs - **Low MCHC (<32 g/dL)**: hypochromic (pale) RBCs - **Reticulocytes low or low-normal**: marrow not responding adequately because it lacks iron substrate **Iron studies** (definitive): - **Serum ferritin LOW (<12 ng/mL in women, <24 ng/mL in men)**: best marker of iron stores; low ferritin is virtually diagnostic of iron deficiency. Note: ferritin is an acute-phase reactant, so infection/inflammation may falsely elevate it. - **Serum iron LOW (<60 µg/dL)** - **Total iron-binding capacity (TIBC) HIGH (>400 µg/dL)**: reflects increased transferrin (iron transport protein); the body upregulates transferrin to scavenge available iron - **Transferrin saturation LOW (<16%)**: calculated as (serum iron / TIBC) × 100; low saturation confirms iron scarcity **Peripheral blood smear**: microcytic, hypochromic RBCs; possible target cells CLINICAL MANIFESTATIONS: **General anemia symptoms**: Fatigue, weakness, dyspnea on exertion (especially climbing stairs—common complaint in Philippine patients with limited healthcare access), tachycardia, dizziness, headache, pallor (assess conjunctivae, nail beds in darker-skinned patients). **Specific signs of iron deficiency**: - **Glossitis**: inflamed tongue with loss of papillae; tongue appears beefy red and sore - **Angular cheilitis**: cracks at angles of mouth - **Koilonychia**: "spoon-shaped" nails, concave nails that can hold a drop of water; pathognomonic (specific) for iron deficiency but occurs only with chronic severe deficiency - **Pica**: craving ice, starch, clay, or non-food items (common in severe iron deficiency); exact mechanism unknown but may relate to altered taste/smell - **Gastric changes**: achlorhydria (loss of gastric acid) in severe chronic deficiency impairs absorption further MANAGEMENT: **Identify and treat the cause**: Investigate source of blood loss. In adults, especially men and postmenopausal women, GI bleeding must be excluded via upper and lower endoscopy before attributing anemia to "diet." In the Philippines, H. pylori screening and treatment is important. **Iron replacement therapy**: **Oral iron therapy** (first-line): - **Ferrous sulfate 325 mg (approximately 65 mg elemental iron)** once to three times daily - **Take on an empty stomach** (best absorption) or with a meal if GI upset; avoid milk, antacids, tea, coffee, and calcium supplements within 2 hours (they bind iron) - Give with **vitamin C** (ascorbic acid, e.g., orange juice) to enhance absorption; vitamin C reduces ferric iron to ferrous form, which is better absorbed - **Expected response**: Reticulocyte count rises within 3–5 days (marrow sees available iron and increases RBC production). Hemoglobin rises ~1 g/dL per month. CBC is rechecked at 4–6 weeks and monthly thereafter until Hgb normalizes. - **Adverse effects**: GI upset (nausea, constipation, abdominal discomfort—affect ~20% of patients). Nausea can be mitigated by taking with food (despite reduced absorption) or switching to a slower-release preparation. **Black, tarry stools are expected** (iron oxidizes in GI tract) and are harmless—patient teaching is essential to prevent discontinuation. - **Liquid iron preparations**: For young children or those unable to swallow pills; give **through a straw** to prevent teeth staining (iron stains enamel brown). - **Duration**: Continue iron for 3–6 months **after hemoglobin normalizes** to replete iron stores. Many patients discontinue once they "feel better," but stores remain depleted, and anemia recurs quickly. **Parenteral iron therapy** (when oral fails): - Indicated for: malabsorption (celiac disease, gastric surgery), intolerance to oral iron, or need for rapid repletion - **Iron dextran** (intramuscular or IV) - **Iron sucrose** (IV only; safer, fewer reactions than iron dextran) - **IM iron given by Z-track technique**: Inject into gluteus maximus using a new needle after drawing up the drug (prevents subcutaneous staining and discomfort). Z-track involves displacing skin laterally before injection and releasing after; this seals the injection tract and prevents leakage into subcutaneous tissue. - **Iron dextran requires a test dose** (25 mg IM or IV) because anaphylaxis is possible (rare but serious); observe for 30 minutes before giving the full dose. Iron sucrose is safer with fewer anaphylactic reactions. **Response to therapy**: - Reticulocytosis begins in 3–5 days (marrow begins producing RBCs as iron becomes available) - Hgb rise: ~1 g/dL per month on adequate oral iron, faster with parenteral iron - Symptom improvement: fatigue, dyspnea improve within weeks as Hgb rises - Normalization: goal Hgb to mid-normal range; continue replacement for 3–6 months to restore stores PATIENT TEACHING: - **Cause and source of bleeding**: Emphasize importance of investigating/treating GI loss, menstrual management in women - **Dietary sources of iron**: Heme iron (red meat, poultry) is 15–35% absorbed; nonheme iron (legumes, leafy greens, fortified cereals—staples in Filipino diet) is 2–20% absorbed. In Philippine context, teach families that beans (mongo, lentils), dark leafy vegetables (kangkong, pechay), and iron-fortified rice contribute meaningfully, especially when combined with vitamin C. - **Adherence**: Iron therapy only works if taken consistently. Address side effects, explain the black stools, emphasize that improvement takes weeks. - **Duration**: Continue iron for months after Hgb normalizes to replete stores and prevent relapse NURSING DIAGNOSES (NANDA): - **Fatigue** related to tissue hypoxia and reduced oxygen-carrying capacity (Maslow level 2: physiologic) - **Activity intolerance** related to insufficient hemoglobin and dyspnea on exertion - **Risk for deficient knowledge** related to iron replacement therapy and dietary management - **Risk for noncompliance** related to side effects of oral iron (GI upset, black stools) Nursing interventions focus on energy conservation (cluster care, allow rest periods), administering iron therapy correctly, patient teaching (mechanism of action, side effects, dietary sources, adherence), and monitoring response (serial CBC, symptom resolution).

Vitamin B12 (cobalamin) deficiency causes a distinct macrocytic, megaloblastic anemia with potentially devastating neurologic consequences. Pernicious anemia, an autoimmune subset of B12 deficiency, is particularly important in elderly populations and requires lifelong management. PATHOPHYSIOLOGY: Vitamin B12 is essential for DNA synthesis (especially in rapidly dividing cells like RBCs and WBCs) and myelin formation (neurologic function). B12 is found naturally only in animal products: meat, fish, dairy, eggs. The body stores approximately 2–5 mg of B12, primarily in the liver, which can last 2–5 years—so dietary deficiency develops slowly. B12 absorption is complex and vulnerable at multiple points: 1. B12 in food is released by gastric acid and pepsin 2. B12 binds to **intrinsic factor (IF)**, a glycoprotein produced by gastric parietal cells 3. The B12-IF complex travels to the terminal ileum, where it is absorbed via specific receptors 4. B12 is transported in plasma bound to transcobalamin (TC) II If any step fails, B12 deficiency develops. CAUSES OF B12 DEFICIENCY: **Pernicious anemia** (most common cause in developed countries): - **Autoimmune destruction of gastric parietal cells** (which produce intrinsic factor) - Associated with other autoimmune conditions: thyroiditis, vitiligo, Addison disease - Antibodies against parietal cells and/or intrinsic factor can be detected - **Genetic predisposition**: familial clustering noted; more common in Northern European ancestry but occurs in all populations - Onset: typically age >50–60 (hence "pernicious"—serious condition) - Progressive: initially, remaining parietal cells compensate, then B12 levels fall precipitously **Other causes of B12 deficiency**: - **Gastrectomy** (surgical removal of stomach): loss of intrinsic factor-producing tissue; occurs in patients with gastric cancer, severe ulcer disease, or obesity surgery - **Ileal disease**: Crohn disease, celiac disease, or surgical resection of terminal ileum impairs B12 absorption site - **Strict vegan diet**: no animal products means no B12 intake; develops over years as body stores deplete - **H. pylori infection** and **chronic atrophic gastritis**: reduce gastric acid and parietal cell function - **Medications**: metformin (impairs B12 absorption), proton-pump inhibitors and H2-blockers (reduce gastric acid needed for B12 release), colchicine (mucosal damage) LABORATORY FINDINGS: **CBC**: - **Low hemoglobin and hematocrit** - **High MCV (>100 fL)**: macrocytic RBCs, often very elevated (110–140 fL) - **Low reticulocyte count**: marrow fails to compensate appropriately despite stimulus; this is paradoxical—in normal anemia, reticulocytes rise, but in B12 deficiency, abnormal DNA synthesis prevents normal RBC maturation - **Peripheral blood smear**: **hypersegmented neutrophils** (>5 lobes, diagnostic sign) and **megaloblastic RBCs** (large, immature-appearing cells) - **Pancytopenia** possible: affects WBCs and platelets too, though to lesser degree **B12-specific tests**: - **Serum B12 level LOW (<200 pg/mL; normal >200–300 pg/mL)** - **Methylmalonic acid (MMA) ELEVATED**: more sensitive for B12 deficiency than serum B12; B12 is a cofactor for MMA metabolism; deficiency causes MMA accumulation - **Serum homocysteine ELEVATED**: B12 is needed for homocysteine metabolism; elevation suggests B12 deficiency (also elevated in folate/B6 deficiency) - **Intrinsic factor antibodies**: present in ~50% of pernicious anemia patients; specific for autoimmune etiology - **Parietal cell antibodies**: present in ~90% of pernicious anemia patients; less specific (also in atrophic gastritis) **Schilling test** (historically important for diagnosis; largely replaced by antibody testing): - Measures urinary excretion of radiolabeled oral B12 (with and without intrinsic factor) - **Stage 1**: oral B12 + intrinsic factor → low excretion indicates absorption defect - **Stage 2**: repeat with IF added → normalization indicates pernicious anemia (lack of IF is the problem); persistent low excretion indicates ileal disease (absorption site defect) CLINICAL MANIFESTATIONS: **Hematologic** (common to all anemias): - Fatigue, weakness, pallor, dyspnea on exertion, tachycardia, dizziness, headache **Oral**: - **Glossitis**: beefy red, sore tongue with loss of papillae; patient may complain of burning sensation - Angular cheilitis: cracks at mouth corners **Neurologic** (unique to B12 deficiency—CRITICAL and IRREVERSIBLE if untreated): - **Paresthesias**: tingling in hands and feet; often starts in feet, progresses proximally - **Impaired proprioception**: loss of position sense; patient may not know where limbs are without looking - **Ataxia**: unsteady gait, loss of coordination; positive Romberg sign (unsteady when standing with eyes closed) - **Hyperreflexia and positive Babinski sign**: pyramidal tract involvement - **Cognitive changes**: irritability, apathy, depression, memory loss; **dementia** if untreated for years - **Optic atrophy**: if neglected, may cause vision loss - **Subacute combined degeneration**: pathologic term for spinal cord demyelination (posterior and lateral columns affected) **KEY DIFFERENTIATOR**: Folate deficiency causes identical hematologic and oral findings (macrocytic anemia, glossitis, cheilitis) **but NOT neurologic signs**. This distinction is critical for diagnosis and treatment—giving folate to a B12-deficient patient may improve anemia but worsens neurologic damage (folate allows DNA synthesis to proceed despite B12 deficiency, leading to continued myelin deterioration). Thus, **always correct B12 deficiency first; never give folate alone**. MANAGEMENT: **Diagnosis**: Low B12 level, macrocytosis, neurologic signs, positive intrinsic factor antibodies, or abnormal Schilling test. **Vitamin B12 replacement** (LIFELONG): - Oral B12 cannot be given (lacks intrinsic factor for absorption in pernicious anemia) - **IM cyanocobalamin injections**: standard therapy - **Loading phase**: 1,000 µg IM daily or weekly for 6–8 weeks to replenish depleted stores (liver contains 2–5 mg; restoration takes time) - **Maintenance phase**: **1,000 µg IM monthly indefinitely** (lifelong therapy because parietal cells are permanently damaged) - Sites: gluteal or deltoid muscle - Response: neurologic symptoms may begin to improve within days/weeks if caught early; paresthesias often the first symptom to resolve; ataxia and gait disturbance take longer; cognitive changes improve slowly - **CRITICAL**: Neurologic damage is NOT fully reversible if treatment is delayed. Delayed diagnosis leads to permanent spinal cord damage, cognitive decline, and possibly blindness. Early recognition and treatment are paramount. **Folate supplementation**: Often given concurrently (many causes of B12 deficiency also have folate deficiency from malabsorption or poor diet) but **never as monotherapy in B12 deficiency**. Folate dose: 1–5 mg daily orally or parenteral folic acid. **Treat underlying cause** (when possible): - H. pylori eradication (triple therapy: PPI + amoxicillin + clarithromycin) - Medication adjustment: discontinue metformin if possible; replace PPI with H2-blocker if tolerated - Dietary counseling for vegans: B12 supplements (oral or injection) or fortified foods **Monitoring**: - CBC: Hgb should begin rising within 1 week (marrow now has B12 to synthesize hemoglobin); Hgb normalizes by 4–6 weeks - Neurologic status: paresthesias may improve within weeks; ataxia and cognitive changes take months; permanent damage does not improve - Reticulocyte count: rises appropriately once B12 replacement starts (unlike the paradoxically low count in untreated disease) PATIENT TEACHING: - **Lifelong IM injections**: Emphasize this is not optional; intrinsic factor cannot be replaced, and oral B12 will not be absorbed. Patients must return monthly for injections indefinitely. - **Cause**: If pernicious anemia (autoimmune), explain the immune destruction of parietal cells; if dietary (vegan), explain B12 is only in animal products or fortified foods - **Early symptoms and monitoring**: Teach to report paresthesias, numbness, unsteady gait, memory changes immediately—early treatment prevents permanent neurologic damage - **Family screening**: Familial clustering exists; siblings may be affected COMPLICATIONS OF UNTREATED B12 DEFICIENCY: - **Subacute combined degeneration**: irreversible spinal cord pathology if treatment delayed - **Dementia and cognitive decline**: progressive and potentially permanent - **Blindness from optic atrophy**: if neglected for years - **High-output heart failure**: severe untreated anemia overwhelms cardiac compensation NURSING DIAGNOSES (NANDA): - **Fatigue** related to tissue hypoxia and reduced oxygen-carrying capacity (Maslow level 2) - **Ineffective tissue perfusion** (neurologic) related to demyelination from B12 deficiency - **Risk for injury** related to ataxia and proprioceptive loss - **Deficient knowledge** related to lifelong IM B12 therapy and dietary sources - **Risk for noncompliance** related to monthly injections and lack of understanding of irreversibility of neurologic damage Nursing interventions: Safety measures (assist with ambulation, prevent falls), teach the importance of lifelong adherence to IM therapy, assess neurologic status monthly (paresthesias, gait, cognition), support adherence with reminder systems for monthly appointments, provide nutritional counseling especially for vegans/vegetarians.

Aplastic anemia is a life-threatening disorder of bone marrow failure resulting in pancytopenia (reduction in all three cell lines: RBCs, WBCs, and platelets). Unlike anemias from nutritional deficiency or hemolysis, aplastic anemia reflects the marrow's inability to produce cells—a fundamentally different pathophysiology. PATHOPHYSIOLOGY: In aplastic anemia, the bone marrow becomes hypocellular (few hematopoietic cells) while fat spaces expand. The cause is often idiopathic (no identifiable trigger; ~50% of cases), but known triggers include drugs, chemicals, radiation, and viral infections. Proposed mechanisms include: (1) direct toxic injury to hematopoietic stem cells, (2) autoimmune destruction of stem cells (especially in acquired aplasia), and (3) replacement of marrow by fibrosis or malignancy. CAUSES: **Idiopathic** (~50%): No identifiable cause; presumed autoimmune destruction of stem cells. **Drug-induced**: - **Dose-related**: Chemotherapy (intentional marrow suppression; reversible upon stopping), some antibiotics (fluoroquinolones), NSAIDs - **Idiosyncratic** (unpredictable; not dose-related): - **Chloramphenicol** (antibiotic): historically notorious for aplasia; now rare due to restricted use in developed countries, but still used in resource-limited settings (Philippines) for certain infections; risk ~1 in 25,000–40,000 - Antithyroid drugs (propylthiouracil, methimazole) - Anticonvulsants (phenytoin) - Sulfonamides **Chemical exposure**: - **Benzene**: occupational exposure in paint, pesticide industries - Insecticides, herbicides **Radiation**: - **Ionizing radiation**: occupational, accidental, or intentional (cancer therapy) **Viral infections**: - **Epstein-Barr virus (EBV)**, cytomegalovirus (CMV), hepatitis A/C, HIV - Viral infection may trigger autoimmune marrow destruction **Other**: - **Paroxysmal nocturnal hemoglobinuria (PNH)**: complement-mediated destruction of blood cells; ~10% of aplastic anemia patients have PNH - Pregnancy: rare, idiopathic marrow suppression reversible post-delivery LABORATORY FINDINGS: **CBC**: - **Hemoglobin LOW**: anemia component - **WBC LOW** (leukopenia): typically <4,000, often <2,000 - **Platelets LOW** (thrombocytopenia): typically <50,000, often <20,000 - **MCV**: typically **normocytic** (80–100 fL) and **normochromic** (normal MCHC); cells are normal-sized but too few - **Reticulocyte count LOW**: inappropriately low given anemia; reflects marrow failure - **RBC morphology**: relatively normal on smear (no hypochromia, no abnormal shapes) **Bone marrow examination** (diagnostic confirmation): - **Aspiration**: hypocellular (cellularity <25%, often <10%; normal ~50%); mostly fat spaces; few hematopoietic cells - **Biopsy**: confirms hypocellularity; rules out fibrosis, leukemia, or metastatic disease - **Cytogenetics**: rule out myelodysplasia or leukemia mimicking aplasia **Other labs**: - **Reticulocyte count**: LOW (failure to respond to anemia) - **Iron studies**: often HIGH ferritin (from hemolysis of transfused RBCs over time) and high serum iron (as marrow doesn't use iron to make hemoglobin) - **LDH, bilirubin, haptoglobin**: usually normal (no hemolysis) - **Flow cytometry**: rules out PNH (absent CD55/CD59 on blood cells) CLINICAL MANIFESTATIONS: Manifestations reflect deficiency of all three cell lines: **Anemia** (low RBCs): - Fatigue, weakness, pallor, dyspnea on exertion, tachycardia **Leukopenia** (low WBCs), particularly neutropenia (low neutrophils): - **Recurrent infections** (bacterial, fungal); infections are often severe and life-threatening - Fever, chills - Oral/pharyngeal ulcers and infections - Perirectal infections, abscesses - **Sepsis and shock** from opportunistic organisms - ANC <500 is particularly dangerous; <200 is critical **Thrombocytopenia** (low platelets): - **Petechiae** (pinpoint red spots), **purpura** (larger purple patches), especially on lower extremities - **Spontaneous bleeding**: gum bleeding, nosebleeds (epistaxis), bleeding from GI tract (hematochezia) - **Intracranial hemorrhage**: life-threatening; can occur spontaneously when platelets <10,000 - Menorrhagia (heavy menstruation) in women CLINICAL SEVERITY (International Prognostic Scoring System, IPSS) depends on: - Degree of cytopenia: the lower the CBC values, the worse the prognosis - Age: younger patients generally have better outcomes - BM cellularity: more severely hypocellular = worse prognosis MANAGEMENT: **Remove causative agent** (if identified): - Discontinue suspected drug (chloramphenicol, antithyroid drugs, anticonvulsants) - Avoid further chemical/radiation exposure - Treat any underlying viral infection (e.g., hepatitis C with antivirals) **Supportive care** (mainstay of treatment while awaiting marrow recovery or transplant): - **Transfusions**: - RBC transfusions for symptomatic anemia (typically goal Hgb >8 g/dL to maintain function) - Platelet transfusions for thrombocytopenia when <20,000 or <10,000 if bleeding/invasive procedures planned; frequent transfusions may lead to platelet alloimmunization (platelet refractoriness) - **Iron overload risk**: repeated transfusions deposit iron in heart, liver, pancreas; iron chelation therapy may be needed - **Transfusion-transmitted infections** (rare but possible): hepatitis B/C, HIV, bacterial contamination - **Transfusion reactions**: febrile, allergic, acute hemolytic (if type mismatch) - **Infection prevention**: - **Protective (reverse) isolation** for ANC <500: private room, strict hand hygiene, no fresh flowers/uncooked foods (bacterial contamination risk), limited visitors - **Prophylactic antibiotics**: options include fluoroquinolones (e.g., levofloxacin) to reduce bacterial infections in severe neutropenia - **Antifungal prophylaxis**: fluconazole or other azoles to prevent candidiasis when ANC <500 for prolonged period - **Antibiotic therapy for fever**: fever in neutropenic patient (ANC <500, temp >38.3°C) is an emergency; broad-spectrum antibiotics (e.g., ceftazidime, piperacillin-tazobactam) started immediately without waiting for cultures - Meticulous oral hygiene - Monitor temperature closely; report any fever immediately - **Platelet transfusion management**: - Minimize bleeding risk (avoid IM injections, use soft toothbrush, avoid rectal manipulation, use gentle handling) - Transfuse prophylactically when <20,000 (or <10,000 if clinically stable) **Immunosuppressive therapy**: - **Antithymocyte globulin (ATG)** and **cyclosporine (CsA)** together are first-line definitive treatment - Mechanism: deplete or suppress T lymphocytes presumed to be destroying hematopoietic stem cells (fits the autoimmune model of aplastic anemia) - Response rate: 50–70% achieve transfusion independence and improvement in CBC - **ATG**: IV infusion (higher risk of serum sickness, anaphylaxis); premedicate with acetaminophen, diphenhydramine, hydrocortisone; test dose sometimes given - **Cyclosporine**: oral; monitor levels and renal function - **G-CSF** (granulocyte colony-stimulating factor): may be added to boost neutrophil production; improves infection risk - Timeline: improvement takes weeks to months; CBC begins to rise at 6–12 weeks if responding - Side effects: infection risk (immunosuppression), kidney dysfunction (cyclosporine), GI upset, headache, opportunistic infections **Hematopoietic stem cell transplantation (HSCT/bone marrow transplant)**: - **Curative therapy**, especially for younger patients (<50 years) with matched sibling or unrelated donor - Conditioning regimen (chemotherapy and/or radiation) ablates diseased marrow; donor cells engraft and establish new hematopoiesis - **Allogeneic transplant** (from donor): best outcomes for severe aplastic anemia; comorbidities, age, and donor availability limit use - **Autologous transplant** (patient's own cells): rarely used in aplastic anemia (unclear benefit) - **Graft-versus-host disease (GVHD)**: major complication where donor immune cells attack recipient tissue - **Graft failure**: engrafted cells fail to establish; requires second transplant - Indications: young patients, severe aplasia, failure to respond to immunosuppression, relapse after immunosuppression **Treatment decisions** depend on: - **Age**: Younger (<50) and with matched donor → HSCT preferred (curative) - Older (>50) and/or no matched donor → Immunosuppression (ATG/CsA) first; HSCT if failure - **Disease severity**: Severe aplasia often proceeds to HSCT sooner - **Performance status**: Can patient tolerate aggressive therapy? PATIENT AND FAMILY TEACHING: - Cause (if known) and treatment plan - **Infection prevention**: importance of isolation when ANC <500, prompt reporting of fever (infection is major cause of death in aplastic anemia) - **Bleeding precautions**: soft toothbrush, avoid trauma, report bleeding, importance of platelet transfusions - **Medication adherence**: immunosuppressive drugs must be taken as prescribed; monitoring labs critical - **Expected duration**: recovery from immunosuppression takes months; HSCT is intensive and carries significant risk but offers cure - **Emotional support**: psychological impact of diagnosis, long-term treatment, and outcome uncertainty COMPLICATIONS: - **Severe infection/sepsis**: leading cause of death if treatment delayed or ineffective - **Hemorrhage**: spontaneous ICH, GI bleeding when platelets <10,000 - **Myelodysplasia or acute leukemia**: ~10% of aplastic anemia patients progress to these conditions over 10 years; likely from clonal evolution of remaining stem cells - **Iron overload**: from chronic transfusions NURSING DIAGNOSES (NANDA): - **Fatigue** related to tissue hypoxia from anemia (Maslow level 2) - **Risk for infection** related to neutropenia (ANC <500) (Maslow level 2—safety) - **Risk for bleeding** related to thrombocytopenia (Maslow level 2—safety) - **Deficient knowledge** related to infection/bleeding prevention and treatment (Maslow level 3—learning) - **Anxiety/fear** related to serious diagnosis and uncertain prognosis Nursing priorities (Maslow-based): 1. **Physiologic/safety**: Prevent infection (isolation, monitor ANC, fever management), prevent bleeding (transfusions, precautions) 2. **Activity/rest**: Balance activity with rest; minimize exertion when Hgb very low 3. **Nutrition**: Maintain adequate nutrition despite immunosuppressive side effects (nausea, oral ulcers) 4. **Psychosocial**: Support coping, provide information, facilitate family involvement

Hemolytic anemia results from premature destruction of RBCs faster than the bone marrow can replace them. The hallmark is a **high reticulocyte count** (marrow compensating for loss) combined with signs of RBC breakdown. Causes are diverse—inherited disorders, autoimmune, transfusion reactions, mechanical damage—requiring careful diagnostic thinking. PATHOPHYSIOLOGY: Normally, RBCs live ~120 days before being removed by the spleen and liver (reticuloendothelial system). In hemolytic anemia, RBCs are destroyed in <120 days—sometimes within hours in severe cases. As the spleen and liver process destroyed RBCs, hemoglobin is broken down: - **Heme** → bilirubin (conjugated and unconjugated) - **Globin** → amino acids (reused or metabolized) - **Iron** → bound to haptoglobin, eventually stored or reused The bone marrow senses the loss and increases RBC production (erythropoiesis), causing a **high reticulocyte count** (>2%, sometimes >20% in severe hemolysis). However, if hemolysis is severe, even maximum marrow output cannot keep pace, and anemia develops. The massive RBC turnover and bilirubin load strain the liver and spleen. CAUSES OF HEMOLYTIC ANEMIA: **Inherited (intrinsic RBC defects)**: **Hemoglobinopathies**: - **Sickle cell disease (HbS)**: abnormal hemoglobin polymerizes under hypoxia, deoxygenation, or acidosis, causing RBCs to sickle (become rigid, crescent-shaped). Sickled cells obstruct blood vessels, causing: - **Vaso-occlusive crises**: sudden severe pain (typically bone pain, especially femur and ribs), swelling, inflammation; triggered by hypoxia, dehydration, infection, cold, acidosis - **Acute chest syndrome**: chest pain, dyspnea, infiltrate on CXR; high mortality - **Organ infarction**: bone necrosis (especially femoral/humeral heads → avascular necrosis), splenic sequestration crisis (massive splenomegaly, shock), hepatic or renal infarction - Chronic hemolysis with jaundice, splenomegaly, gallstones (pigment stones from bilirubin) - **Acute splenic sequestration**: especially in young children; sudden massive splenomegaly, drop in Hgb, hypovolemic shock - **Aplastic crisis**: transient marrow failure (often viral trigger, e.g., parvovirus B19); reticulocyte count paradoxically drops; Hgb falls abruptly - Management of crisis: IV hydration (LR or NS, not hypotonic fluids that promote sickling), oxygen, pain control (IV opioids; NSAIDs may precipitate renal problems), treat infection, exchange transfusion if severe - **Hydroxyurea**: increases fetal hemoglobin (HbF), which doesn't polymerize; reduces crisis frequency by 50–90%; also improves hemolysis - **Thalassemia**: defective synthesis of α or β globin chains; leads to hemolysis, iron overload, and extramedullary hematopoiesis. Usually diagnosed in childhood (β-thalassemia major presents at 6–12 months when HbF wanes and HbA demand exceeds production). **Enzyme deficiencies**: - **Glucose-6-phosphate dehydrogenase (G6PD) deficiency**: X-linked, common in African, Mediterranean, and Asian males; RBCs lack antioxidant protection and hemolyze when exposed to oxidative stress (fava beans, sulfonamides, salicylates, infections). Episodes are acute and self-limited; treatment is supportive. **Membrane defects**: - **Hereditary spherocytosis**: defective spectrin or other RBC membrane proteins; spherical RBCs are osmotically fragile and trapped in spleen; hemolysis, jaundice, splenomegaly, gallstones. Osmotic fragility test shows increased RBC lysis in hypotonic saline. Treatment: splenectomy (removes main site of destruction). - **Paroxysmal nocturnal hemoglobinuria (PNH)**: acquired clonal stem cell disorder; lack of complement regulatory proteins (CD55, CD59); complement-mediated hemolysis, thrombosis, and aplasia. Diagnosed by flow cytometry showing absent CD55/CD59. **Acquired (extrinsic RBC damage)**: **Autoimmune hemolytic anemia (AIHA)**: - **Warm AIHA** (most common): IgG antibodies (warm-reactive) bind RBCs, primarily in the spleen where macrophages destroy antibody-coated RBCs. Associated with SLE, lymphoma, idiopathic. - **Cold AIHA** (less common): IgM antibodies (cold-reactive) activate complement; RBCs are destroyed in the liver. Often follows infection (EBV, CMV, Mycoplasma). - **Direct Coombs test: POSITIVE** (detects IgG or complement on RBCs), confirming immune destruction. - Treatment: corticosteroids (suppress antibody production/macrophage activity), IVIG, splenectomy if steroid-refractory, rituximab (anti-CD20 B cells). **Transfusion reactions**: - **Acute hemolytic transfusion reaction** (ABO incompatibility): IgM antibodies in recipient plasma attack donor RBCs, activating complement and causing hemolysis. Symptoms: fever, chills, back pain, dark urine, dyspnea, hypotension within minutes of starting transfusion. STOP transfusion, aggressive fluid resuscitation to prevent acute kidney injury. Diagnosis: recheck blood type/crossmatch, send urine for hemoglobin. - **Delayed hemolytic transfusion reaction** (non-ABO alloantibodies): occurs 3–7 days post-transfusion; milder than acute reaction. Jaundice, anemia worsens. **Mechanical hemolysis**: - **Microangiopathic hemolytic anemia (MAHA)**: mechanical fragmentation of RBCs as they pass through small vessels with thrombi or artificial surfaces (mechanical heart valves, dialysis membranes). Schistocytes (fragmented RBCs) seen on smear. Associated with DIC, thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome (HUS). - **Prosthetic heart valve hemolysis**: chronic low-grade hemolysis; usually tolerated but occasionally becomes severe. **Infections**: - **Malaria**: Plasmodium parasites destroy RBCs; common in endemic areas (not Philippines currently, but relevant for international practice) - **Clostridial sepsis**, **EBV**, **CMV**: direct damage or immune-mediated destruction **Drugs**: methyldopa, quinidine, NSAIDs, sulfonamides, penicillins (can trigger immune response) **Splenic disorders**: splenomegaly from any cause (portal hypertension, lymphoma, infectious mononucleosis) increases RBC sequestration. LABORATORY FINDINGS: **CBC**: - **Anemia**: Hgb and Hct below normal - **MCV**: typically **normocytic** (80–100 fL) because new RBCs are released prematurely as reticulocytes (reticulocytes are larger than mature RBCs, raising MCV) - **Reticulocytes: HIGH (>2%, often >5–20% or higher)**; this is the KEY finding distinguishing hemolysis from other causes of anemia; the marrow is compensating maximally - **WBC and platelets**: usually normal (unless cause also affects these lines) - **Peripheral blood smear**: depends on cause - **Spherocytes**: small, dense RBCs in AIHA or hereditary spherocytosis - **Schistocytes**: fragmented RBCs in MAHA or DIC - **Sickle cells**: obvious in sickle disease - **Polychromasia**: blue-tinged RBCs (immature, RNA-containing) from high reticulocyte population - **Nucleated RBCs**: RBCs released early from marrow; indicates severe hemolysis **Evidence of RBC breakdown**: - **Indirect (unconjugated) bilirubin: ELEVATED** (>2 mg/dL suggests hemolysis); bilirubin from heme breakdown - **Direct (conjugated) bilirubin**: normal or mildly elevated (liver handles bilirubin normally in uncomplicated hemolysis) - **LDH: ELEVATED** (from RBC destruction and release of intracellular contents) - **Haptoglobin: LOW or ABSENT** (<10 mg/dL or undetectable); haptoglobin binds free hemoglobin from lysed RBCs, so severe hemolysis depletes haptoglobin - **Urine hemoglobin**: present if intravascular hemolysis (free hemoglobin filtered); **dark urine** ("cola-colored") from hemoglobinuria is classic - **Reticulocyte count: ELEVATED** **Immune-specific tests**: - **Direct antiglobulin test (Direct Coombs): POSITIVE** in immune hemolysis (AIHA, HDN, transfusion reaction); negative in non-immune causes (hereditary spherocytosis, sickle cell, MAHA) - **Indirect Coombs**: positive if alloantibodies present (transfusion incompatibility) - **Flow cytometry**: detects specific antibodies or complement on RBCs; rules out PNH (absent CD55/CD59) CLINICAL MANIFESTATIONS: **Anemia symptoms**: - Fatigue, weakness, pallor, dyspnea on exertion, tachycardia, dizziness **Hemolysis signs**: - **Jaundice**: yellowing of sclera and skin from elevated indirect bilirubin; may appear within hours of hemolysis onset - **Dark urine**: cola-colored or port-wine colored from hemoglobinuria; pathognomonic for intravascular hemolysis - **Splenomegaly**: from increased RBC destruction and filtering; often palpable, sometimes massive - **Hepatomegaly**: from bilirubin processing - **Fever**: from immune activation or infection (in some cases) - **Tachycardia and tachypnea**: compensatory for anemia **Sickle cell crisis manifestations**: - **Vaso-occlusive crisis**: severe bone pain (especially femur), swelling, fever; often mistaken for infection or drug-seeking behavior (a persistent bias in ED practice globally; requires vigilant advocacy) - **Acute chest syndrome**: chest pain, dyspnea, infiltrate; life-threatening - **Splenic sequestration**: acute splenomegaly, severe anemia, shock - **Aplastic crisis**: sudden drop in Hgb and reticulocytes (viral trigger) MANAGEMENT: **General supportive care**: - **Folic acid supplementation**: 1–5 mg daily; high RBC turnover depletes folate - **Transfusions**: as needed for symptomatic anemia (goal Hgb >8–9 g/dL for activity); in sickle disease, simple transfusion or exchange transfusion to lower HbS <30–50% reduces sickling - **Avoid triggers** in sickle disease: dehydration, hypoxia, cold, infection, altitude - **Hydration**: maintain good hydration; in sickle disease, IV LR/NS during crisis (avoids hyposmolarity promoting sickling) **Cause-specific treatment**: **Autoimmune hemolytic anemia**: - **Corticosteroids**: prednisone 1 mg/kg/day, then taper; suppresses antibody production and macrophage activity; ~60–70% respond - **IVIG** (intravenous immunoglobulin): IV immunoglobulin blocks macrophage Fc receptors, reducing RBC destruction; used if steroid-refractory or rapid disease - **Splenectomy**: removes major site of RBC destruction; ~50–60% achieve remission if they respond to steroids first; curative in hereditary spherocytosis - **Rituximab**: anti-CD20 (targets B lymphocytes producing antibodies); reserved for refractory cases - **Warm vs. cold AIHA management differs**: cold AIHA requires avoiding cold exposure; transfuse via warmed blood tubing; respond poorly to steroids but may improve with rituximab or complement inhibitors (eculizumab); warm AIHA responds better to steroids **Sickle cell disease**: - **Crisis management**: IV hydration (LR or NS), oxygen (maintain O2 sat >95%), pain control (IV opioids; avoid morphine in some patients due to histamine release), treat infections - **Hydroxyurea**: increases HbF (fetal hemoglobin), which doesn't polymerize; reduces crisis frequency 50–90%; also improves hemolysis; first-line disease-modifying agent - **Exchange transfusion**: in severe crisis or acute chest syndrome; replace sickled RBCs with normal RBCs to lower HbS <30% - **Bone marrow/stem cell transplantation**: curative, especially in children; considered if frequent crises or complications despite hydroxyurea **G6PD deficiency**: - **Avoid triggers**: fava beans, sulfonamides, salicylates - **Supportive care**: hydration, folic acid; hemolytic episodes are usually self-limited - **Transfusion**: if Hgb drops dangerously (usually not needed as episodes resolve in days) **Mechanical hemolysis (mechanical heart valve)**: - **Supportive care**: folic acid, consider iron supplementation (chronic GI blood loss) - **Surgical replacement** of valve if hemolysis becomes severe **Transfusion reaction prevention**: - **Type and crossmatch**: prevent ABO incompatibility - **Compatible blood**: verify blood type at bedside using two patient identifiers - **Prompt recognition and management** of hemolytic reaction: stop transfusion, IV saline, monitor urine output PATIENT TEACHING: - **Cause of hemolysis**: whether hereditary or acquired - **Trigger avoidance** (sickle cell): dehydration, cold, high altitude, stress - **Medication adherence**: folic acid daily, hydroxyurea for sickle disease - **Infection prevention**: prompt treatment of infections (infection triggers crises) - **Genetic counseling**: if inherited disorder (sickle cell, hereditary spherocytosis, G6PD) - **Complications and warning signs**: severe pain, dyspnea, pallor, dark urine, fever NURSING DIAGNOSES (NANDA): - **Fatigue** related to tissue hypoxia from anemia (Maslow level 2) - **Acute pain** related to vaso-occlusive crisis in sickle cell disease (if applicable) - **Impaired tissue perfusion** related to sickling or RBC destruction (if applicable) - **Risk for deficient knowledge** related to disease process and trigger avoidance Nursing priorities: 1. **Pain management** in sickle crisis (aggressive, timely opioid administration; assess for biases against pain management in sickle disease patients) 2. **Hydration** and oxygen to prevent sickling and organ infarction 3. **Folic acid and transfusion management** 4. **Patient education** on triggers and chronic management