NLE Immune System & Immunologic Disorders — Autoimmune Disorders and HIV/AIDSDetailed Explanation

The immune system is designed to distinguish 'self' from 'non-self' — a mechanism called self-tolerance. In autoimmune disorders, this system breaks down. The immune system produces autoantibodies (antibodies against the body's own antigens) or self-reactive T cells that target normal body tissues, causing chronic inflammation and progressive tissue damage.

Key characteristics of autoimmune disorders:

• They are more prevalent in women of childbearing age (roughly 20–50 years), which is why many NLE scenarios involve young women.
• They have a genetic predisposition — family history increases risk.
• They follow a relapsing-remitting course: periods of active disease (flares) alternate with periods of minimal symptoms (remission).
• The underlying mechanism varies but is broadly classified under Type II (antibody-mediated cytotoxicity), Type III (immune complex deposition), or Type IV (cell-mediated) hypersensitivity reactions per the Gell and Coombs classification.

For NLE purposes, the most important autoimmune disorders to master are Systemic Lupus Erythematosus (SLE), Scleroderma (Systemic Sclerosis), and Sjögren's Syndrome. These are all chronic, systemic conditions requiring lifelong management and patient education — central nursing responsibilities under RA 9173 (Philippine Nursing Act of 2002).

SLE is a chronic, multisystem autoimmune disease driven primarily by autoantibody formation and immune-complex (Type III hypersensitivity) deposition in tissues. It is the prototypical autoimmune disease for NLE purposes. Think of SLE as a disease that can affect virtually every organ system — it is the 'great mimicker' of other diseases.

PATHOPHYSIOLOGY: In SLE, B cells produce antibodies against double-stranded DNA (dsDNA) and other nuclear antigens. These form immune complexes that deposit in tissues (especially the kidneys, skin, and joints), activate complement, and trigger inflammation. Complement levels (C3, C4) are consumed and thus DECREASE during active disease — this is a key diagnostic clue.

MANIFESTATIONS (organized by system for NLE memorization):

1. SKIN (most visible and NLE-tested): Butterfly (malar) rash — erythematous rash over the cheeks and bridge of the nose, classically SPARING the nasolabial folds. This is the hallmark sign. Also: discoid rash (thick, scaly lesions that can scar), photosensitivity (flares triggered by UV exposure), oral ulcers, and alopecia (patchy hair loss).
2. MUSCULOSKELETAL: Arthralgia and nonerosive arthritis (joints are painful and swollen but do NOT erode — unlike rheumatoid arthritis), myalgia. Morning stiffness is common.
3. RENAL — LUPUS NEPHRITIS: This is the most serious organ involvement and a leading cause of morbidity and mortality. The kidneys are damaged by immune complex deposition. Monitor for: proteinuria, hematuria, elevated creatinine/BUN, edema, and hypertension. Regular urinalysis is a nursing priority.
4. HEMATOLOGIC: Anemia (hemolytic or anemia of chronic disease), leukopenia, thrombocytopenia — predisposing to bleeding risk.
5. CARDIOPULMONARY: Pericarditis (chest pain relieved by leaning forward), pleuritis, increased cardiovascular disease risk.
6. NEUROPSYCHIATRIC: Seizures, psychosis, cognitive changes — collectively called neuropsychiatric SLE (NPSLE).
7. CONSTITUTIONAL: Fatigue (often the most debilitating symptom), fever, weight loss, Raynaud phenomenon (episodic color changes in fingers with cold/stress).

FLARE TRIGGERS (critical for patient teaching):

• Sun/UV exposure — PRIMARY trigger; the most NLE-tested
• Infections (including vaccines if live)
• Physical and emotional stress
• Fatigue and sleep deprivation
• Pregnancy (can trigger flares, especially postpartum)
• Certain drugs (procainamide, hydralazine, isoniazid can cause drug-induced lupus)
• Abrupt steroid discontinuation

DIAGNOSTICS:

• ANA (antinuclear antibody): Positive in ~95–99% of SLE patients — highly SENSITIVE but not specific.
• Anti-dsDNA: Highly SPECIFIC for SLE; titers correlate with disease activity (especially nephritis). Rising anti-dsDNA = worsening disease.
• Anti-Smith (anti-Sm): Also highly SPECIFIC for SLE.
• Complement (C3, C4): DECREASED in active disease (consumed by immune complexes).
• CBC: Anemia, leukopenia, thrombocytopenia.
• Urinalysis: Proteinuria, hematuria, casts indicate nephritis.
• Elevated ESR; CRP may be normal or mildly elevated.

PHARMACOLOGY AND NURSING MANAGEMENT:

1. NSAIDs (e.g., ibuprofen, naproxen): For mild arthralgia and fever. Monitor for GI irritation (administer with food), renal function (can worsen lupus nephritis), and fluid retention.
2. Hydroxychloroquine (Plaquenil) — ANTIMALARIAL — MAINSTAY OF TREATMENT:

• Used for skin manifestations, joint disease, and to REDUCE FREQUENCY OF FLARES.
• KEY NURSING CONSIDERATION: Can cause RETINAL TOXICITY (maculopathy) — requires BASELINE and PERIODIC EYE EXAMINATIONS (ophthalmologic monitoring every 6–12 months).
• Also requires baseline G6PD testing (relevant in Filipino patients, who have higher G6PD deficiency prevalence).

3. Corticosteroids (prednisone): For moderate-to-severe flares and organ-threatening disease.

• Monitor for: Infection risk, hyperglycemia (check blood sugar), hypertension, osteoporosis (calcium and vitamin D supplementation), GI upset, Cushing's features.
• NEVER STOP ABRUPTLY — always taper to prevent adrenal crisis.
• In Philippine public hospitals, prednisone is a readily available and commonly used medication.

4. Immunosuppressants — for severe organ involvement (lupus nephritis, CNS involvement):

• Azathioprine, mycophenolate mofetil: Monitor for bone marrow suppression (CBC monitoring), GI effects, and infection.
• Cyclophosphamide: Used for severe nephritis; monitor for hemorrhagic cystitis (push fluids), bone marrow suppression, and bladder cancer risk.

5. Belimumab (Benlysta): A biologic (B-lymphocyte stimulator inhibitor) for active SLE not well-controlled by standard therapy.

PRIORITY NURSING INTERVENTIONS:

• Strict sun protection: SPF 30+ sunscreen applied 30 minutes before sun exposure, protective clothing, wide-brim hats, avoid peak sun hours (10 AM–4 PM). This is the MOST CRITICAL patient education point.
• Monitor renal function: Daily weight, I&O, edema assessment, urinalysis, BUN/creatinine.
• Monitor for infection: Temperature, WBC — infection can mimic and trigger flares.
• Medication adherence counseling: Do not stop medications without physician guidance.
• Fatigue management: Balance activity and rest; schedule rest periods.
• Family planning: Counsel on pregnancy — SLE can flare during pregnancy and postpartum; certain medications (methotrexate, mycophenolate) are teratogenic.
• Psychosocial support: Body image concerns (rash, hair loss), chronic illness adjustment.

NANDA NURSING DIAGNOSES FOR SLE:

• Impaired Skin Integrity related to photosensitivity and malar rash
• Chronic Pain related to arthralgia and inflammation
• Fatigue related to chronic inflammatory process and anemia
• Risk for Infection related to immunosuppressive therapy
• Excess Fluid Volume related to nephrotic syndrome (if nephritis is severe)
• Ineffective Self Health Management related to complexity of treatment regimen
• Disturbed Body Image related to skin changes and alopecia

SCLERODERMA (SYSTEMIC SCLEROSIS):
Scleroderma is an autoimmune connective tissue disease characterized by three hallmarks: (1) excessive collagen deposition and fibrosis of the skin and internal organs, (2) vascular injury, and (3) immune activation. The word 'scleroderma' literally means 'hard skin' (Greek: skleros = hard, derma = skin). This is a critical memory anchor.

MANIFESTATIONS:

1. SKIN: Thickened, hardened, taut, and shiny skin. Often starts in the fingers (sclerodactyly) and spreads proximally. The face becomes tight and mask-like, with difficulty opening the mouth widely (microstomia) — important for dental care and airway assessment.
2. VASCULAR — RAYNAUD PHENOMENON (early and most common sign): Episodic blanching (white), cyanosis (blue), then redness (red) of the fingers triggered by cold exposure or emotional stress. Remember: W-B-R (White-Blue-Red) or the sequence pallor → cyanosis → rubor. This vascular instability is often the FIRST symptom to appear, sometimes years before skin changes.
3. GI: Esophageal dysmotility — the smooth muscle of the esophagus is fibrotic, causing dysphagia (difficulty swallowing) and severe GERD (gastroesophageal reflux disease). This is a hallmark GI manifestation.
4. PULMONARY — LEADING CAUSE OF DEATH: Interstitial pulmonary fibrosis (progressive scarring of lung tissue) and pulmonary arterial hypertension. Monitor for exertional dyspnea, declining SpO2, and abnormal pulmonary function tests.
5. RENAL — SCLERODERMA RENAL CRISIS: Sudden onset severe hypertension and rapidly progressive renal failure. ACE inhibitors (especially captopril) are the treatment of choice and can be life-saving. This is the ONLY renal emergency in scleroderma and a frequent NLE question.
6. CARDIAC: Myocardial fibrosis, pericarditis.

CREST SYNDROME — Limited Scleroderma:
CREST is the acronym for the limited form of systemic sclerosis with a better prognosis than diffuse disease:

• C — Calcinosis (calcium deposits under the skin)
• R — Raynaud phenomenon
• E — Esophageal dysmotility
• S — Sclerodactyly (skin tightening of fingers)
• T — Telangiectasia (dilated blood vessels visible on skin surface)

NURSING MANAGEMENT OF SCLERODERMA:

• RAYNAUD: Protect from cold — wear gloves (thus this is very relevant in air-conditioned environments, popular in Philippine malls and offices), layer clothing, avoid cold water; smoking cessation (vasoconstriction); vasodilators (calcium channel blockers like nifedipine) as prescribed.
• GERD/DYSPHAGIA: Small, frequent meals; remain upright for at least 30 minutes–1 hour after eating; elevate the head of the bed 6–8 inches; proton pump inhibitors (omeprazole); avoid lying down immediately after meals.
• SKIN CARE: Apply emollients (moisturizers) frequently to prevent skin breakdown; protect from trauma; gentle range-of-motion (ROM) and hand exercises daily to maintain joint mobility and prevent contractures.
• BLOOD PRESSURE AND RENAL MONITORING: Monitor BP at every visit — a sudden hypertensive crisis with rising creatinine signals scleroderma renal crisis; administer ACE inhibitors promptly.
• PULMONARY: Monitor for dyspnea, SpO2, and educate about energy conservation techniques.

SJÖGREN'S SYNDROME:
Sjögren's is an autoimmune disorder where lymphocytes infiltrate and destroy exocrine (moisture-producing) glands — primarily the lacrimal glands (tears) and salivary glands (saliva). It can occur alone (primary Sjögren's) or alongside other autoimmune conditions like SLE or rheumatoid arthritis (secondary Sjögren's).

CLASSIC TRIAD (the NLE memory anchor):

1. Dry eyes (keratoconjunctivitis sicca) — gritty, burning sensation; reduced tear production.
2. Dry mouth (xerostomia) — difficulty chewing and swallowing dry foods, altered taste, burning tongue.
3. Arthritis — joint pain and swelling.

DIAGNOSTICS:

• Anti-Ro (SSA) and anti-La (SSB) antibodies — the specific antibodies for Sjögren's.
• Schirmer test: A small strip of filter paper is placed under the lower eyelid for 5 minutes. Wetting of less than 5 mm indicates reduced tear production (positive test for dry eye).
• Salivary gland biopsy (minor salivary gland from inner lip): Shows lymphocytic infiltration.

NURSING MANAGEMENT OF SJÖGREN'S:

• DRY EYES: Artificial tears (lubricating eye drops) used frequently; sunglasses to protect from wind; avoid dry or smoky environments; use a humidifier.
• DRY MOUTH: Sip water frequently throughout the day; use saliva substitutes; sugar-free gum or candy to stimulate remaining salivary gland function; avoid alcohol-containing mouthwashes (they worsen dryness).
• DENTAL/ORAL CARE: CRITICAL — xerostomia dramatically increases the risk of dental caries (tooth decay) and oral infections (candidiasis). Meticulous oral hygiene: brush after every meal, fluoride toothpaste, regular dental check-ups. This is a HIGH-YIELD NLE nursing intervention.
• SYSTEMIC: Hydroxychloroquine for systemic symptoms; pilocarpine (muscarinic agonist) can stimulate residual gland function.
• Extraglandular involvement: Monitor for lymphoma risk (B cell lymphoma is a serious long-term complication of Sjögren's).

HIV (Human Immunodeficiency Virus) is a RETROVIRUS — meaning it carries its genetic information as RNA and uses a special enzyme called REVERSE TRANSCRIPTASE to convert RNA into DNA inside host cells. This DNA integrates into the host cell's genome, making HIV infection permanent at the cellular level.

The primary target of HIV is the CD4+ T helper lymphocyte — the 'commander' of the immune response. CD4+ T cells coordinate both cellular and humoral immunity. As HIV progressively destroys these cells over years, cell-mediated immunity collapses.

STEP-BY-STEP HIV LIFE CYCLE (important for understanding antiretroviral drug classes):

1. BINDING/ATTACHMENT: HIV attaches to CD4 receptor and co-receptors (CCR5/CXCR4) on the CD4+ T cell surface.
2. FUSION: The viral envelope fuses with the cell membrane, releasing viral RNA into the cell.
3. REVERSE TRANSCRIPTION: Reverse transcriptase converts viral RNA → DNA.
4. INTEGRATION: Integrase enzyme inserts viral DNA into the host cell's nuclear DNA (the virus is now 'hidden' and permanent).
5. TRANSCRIPTION/TRANSLATION: The cell produces viral proteins.
6. ASSEMBLY AND BUDDING: New viral particles are assembled.
7. MATURATION: Protease enzyme cleaves viral proteins into functional units, creating mature, infectious virions.

Each step is a potential drug target — this is the basis of antiretroviral therapy (ART).

PROGRESSION OF HIV INFECTION:

STAGE 1 — ACUTE HIV INFECTION (Seroconversion illness, 2–4 weeks after exposure):

• The virus replicates explosively; viral load is very high.
• CD4 count drops temporarily.
• Flu-like symptoms: fever, sore throat, swollen lymph nodes, rash, myalgia, headache — often mistaken for flu or dengue in the Philippine setting.
• Lasts 1–3 weeks, then resolves spontaneously.
• The patient is HIGHLY INFECTIOUS at this stage.

STAGE 2 — CLINICAL LATENCY (Asymptomatic HIV, Chronic HIV):

• The virus is still replicating but at a slower rate.
• CD4 count gradually declines over months to years (average ~10 years without treatment).
• Patient may have no symptoms or only persistent generalized lymphadenopathy.
• Still infectious — can transmit HIV even with no symptoms.
• With ART: this stage can last decades, and progression to AIDS can be prevented.

STAGE 3 — AIDS (Acquired Immunodeficiency Syndrome):

• CD4 count falls BELOW 200 cells/mm³ (normal: ~500–1,600 cells/mm³), OR
• Presence of AIDS-defining opportunistic infection or malignancy regardless of CD4 count.
• Progressive immune collapse makes the person vulnerable to infections and cancers that a healthy immune system would easily control.
• Without ART: survival is typically 1–3 years.

CD4 COUNT — KEY VALUES TO MEMORIZE:

• Normal: 500–1,600 cells/mm³
• <500: Increased infection susceptibility; start ART
• <200: AIDS diagnosis; start PCP prophylaxis with co-trimoxazole
• <100: Risk for Toxoplasma, Cryptococcus, CMV
• <50: Risk for Mycobacterium avium complex (MAC), CMV retinitis

VIRAL LOAD:

• Measures the number of HIV RNA copies/mL of blood.
• High viral load = more active viral replication = greater risk of progression and transmission.
• Treatment goal: UNDETECTABLE viral load (<50 copies/mL).
• UNDETECTABLE = UNTRANSMITTABLE (U=U): A person with sustained undetectable viral load on ART does NOT sexually transmit HIV — a key counseling and public health message under RA 11166.

THE WINDOW PERIOD — CRITICAL NLE CONCEPT:
The window period is the time between HIV infection and when a test can RELIABLY DETECT it. During this period:

• The person IS infected.
• The person IS infectious (can transmit HIV).
• Standard antibody tests may return NEGATIVE — a FALSE NEGATIVE result.

WINDOW PERIOD BY TEST TYPE:

• 4th-generation antigen/antibody (Ag/Ab) combo test: 18–45 days (detects p24 antigen before antibody develops)
• 3rd-generation antibody tests: 23–90 days
• Nucleic acid test (NAT/RNA PCR): 10–33 days (shortest window — detects the virus itself)

For practical NLE purposes: The antibody window period is approximately 3 months (up to 6 months in rare cases). Anyone tested during this period MUST BE RETESTED after the window period has passed.

NURSING IMPLICATION: A patient who had a possible exposure 2 months ago tests HIV-negative. What is the appropriate nursing action? Counsel the patient that they may be in the window period; advise retesting at 3 months post-exposure; advise safer sex practices and no blood donation in the interim.

As the CD4 count falls, the immune system can no longer defend against microorganisms that are harmless to immunocompetent individuals. These are called OPPORTUNISTIC INFECTIONS (OIs) because they 'take advantage' of the weakened host. They are a leading cause of morbidity and mortality in AIDS patients in the Philippines.

KEY OPPORTUNISTIC INFECTIONS BY CD4 THRESHOLD:

1. PNEUMOCYSTIS JIROVECII PNEUMONIA (PCP) — CD4 < 200:

• The CLASSIC AIDS-defining infection and one of the most common OIs worldwide.
• Presentation: Progressive exertional dyspnea, dry (non-productive) cough, fever, and hypoxemia (low SpO2).
• Diagnosis: Chest X-ray shows bilateral diffuse infiltrates ('ground glass' appearance); LDH elevated; confirmed by bronchoscopy with BAL.
• Treatment: High-dose co-trimoxazole (TMP-SMX) + corticosteroids for moderate-to-severe disease.
• PROPHYLAXIS: Start co-trimoxazole when CD4 < 200 cells/mm³ — this is a critical NLE point.
• Nursing: Monitor SpO2, administer O2, position for comfort (Fowler's or high-Fowler's), breathing exercises.

2. TUBERCULOSIS (TB) — Most common OI in the Philippines:

• TB is endemic in the Philippines (one of the top 30 high-TB-burden countries). HIV dramatically increases the risk of active TB.
• HIV-positive patients may have ATYPICAL presentations: fewer cavitations, more diffuse infiltrates, more extrapulmonary TB (lymph nodes, meningeal).
• Co-infection management: ART + standard TB treatment (DOTS — Directly Observed Treatment Short-course, the Philippine DOH program).
• Nursing: Airborne precautions (negative pressure room, N95 respirator), DOTS compliance monitoring, medication adherence.

3. ORAL AND ESOPHAGEAL CANDIDIASIS:

• Oral thrush (white, curd-like patches in the mouth) is often the FIRST sign of AIDS.
• Esophageal candidiasis (dysphagia, odynophagia) is AIDS-defining.
• Treatment: Fluconazole; nystatin for oral candidiasis.
• Nursing: Oral hygiene, small frequent meals, soft foods, antifungal as prescribed.

4. CRYPTOCOCCAL MENINGITIS — CD4 < 100:

• Cryptococcus neoformans infects the meninges and brain.
• Presentation: Headache, fever, neck stiffness, photophobia — classic meningitis signs, but may be subtle in AIDS.
• Diagnosis: Lumbar puncture — India ink stain shows encapsulated yeast; cryptococcal antigen test.
• Treatment: Amphotericin B followed by fluconazole.
• Nursing: Monitor neurological status, ICP signs, administer antifungals, seizure precautions.

5. TOXOPLASMOSIS (CNS) — CD4 < 100:

• Toxoplasma gondii reactivation causes brain abscesses.
• Presentation: Focal neurological deficits, fever, headache, seizures.
• CT/MRI shows ring-enhancing lesions in the brain.
• Treatment: Pyrimethamine + sulfadiazine + leucovorin.
• Prophylaxis: Co-trimoxazole also provides prophylaxis against toxoplasmosis.

6. CYTOMEGALOVIRUS (CMV) RETINITIS — CD4 < 50:

• Presents as painless, progressive vision loss — 'floaters,' blurred vision, visual field defects.
• If untreated, leads to BLINDNESS.
• Ophthalmologic examination is essential for monitoring.
• Treatment: Ganciclovir, valganciclovir.

7. MYCOBACTERIUM AVIUM COMPLEX (MAC) — CD4 < 50:

• Disseminated infection causing fever, night sweats, weight loss, diarrhea, anemia.
• Treatment: Azithromycin or clarithromycin + ethambutol.

8. AIDS-DEFINING MALIGNANCIES:

• KAPOSI SARCOMA: Vascular tumor presenting as purple/brown skin lesions; caused by HHV-8. Can also involve internal organs.
• NON-HODGKIN LYMPHOMA: B-cell lymphoma, often involving CNS.
• INVASIVE CERVICAL CANCER: HPV-related; HIV dramatically increases risk.

9. AIDS WASTING SYNDROME: Involuntary weight loss >10% of baseline body weight + chronic diarrhea or weakness.
10. HIV ENCEPHALOPATHY (AIDS DEMENTIA COMPLEX): Progressive cognitive decline, motor dysfunction, behavioral changes.

NURSING DIAGNOSES FOR OPPORTUNISTIC INFECTIONS:

• Risk for Infection related to immunosuppression (CD4 <200)
• Impaired Gas Exchange related to PCP pneumonia
• Imbalanced Nutrition: Less than Body Requirements related to wasting, dysphagia, diarrhea
• Impaired Oral Mucous Membrane related to oral candidiasis
• Disturbed Sensory Perception (visual) related to CMV retinitis
• Risk for Injury related to neurological manifestations (seizures, cognitive changes)

Antiretroviral therapy (ART) is the cornerstone of HIV management. It does not CURE HIV but it effectively controls viral replication, prevents immune deterioration, reduces transmission, and allows HIV-positive individuals to live near-normal, productive lives. Under Philippine DOH programs and RA 11166, ART is provided free of charge through Social Hygiene Clinics (SHCs) and HIV Treatment Hubs nationwide.

PRINCIPLE OF COMBINATION ART:
ART uses at least 3 drugs from 2 or more drug classes — this is called Highly Active Antiretroviral Therapy (HAART) or simply combination ART. The rationale: HIV mutates rapidly. Using a single drug allows resistant mutants to survive and reproduce, causing treatment failure. Using 3 or more drugs simultaneously makes it nearly impossible for the virus to develop resistance to all drugs at once.

ANTIRETROVIRAL DRUG CLASSES (target the HIV life cycle):

1. NRTIs (NUCLEOSIDE REVERSE TRANSCRIPTASE INHIBITORS):

• Mechanism: Incorporate into the viral DNA chain, causing chain termination — blocks reverse transcription.
• Examples: Tenofovir (TDF), Lamivudine (3TC), Zidovudine (AZT/ZDV), Emtricitabine (FTC), Abacavir (ABC).

• KEY SIDE EFFECTS:

  • Zidovudine (AZT): BONE MARROW SUPPRESSION → anemia, neutropenia. Monitor CBC regularly.
  • Tenofovir: NEPHROTOXICITY and decreased bone mineral density. Monitor renal function.
  • Abacavir: HYPERSENSITIVITY REACTION (fever, rash, GI upset, respiratory symptoms) — SCREEN FOR HLA-B*5701 before starting; abacavir is CONTRAINDICATED in HLA-B*5701-positive patients. The reaction is potentially fatal if rechallenge occurs.

2. NNRTIs (NON-NUCLEOSIDE REVERSE TRANSCRIPTASE INHIBITORS):

• Mechanism: Bind directly to reverse transcriptase and block it (different binding site than NRTIs).
• Examples: Efavirenz (EFV), Nevirapine (NVP), Rilpivirine.

• KEY SIDE EFFECTS:

  • Efavirenz: CNS effects — vivid dreams, dizziness, insomnia (especially first 2–4 weeks); TERATOGENIC (Category D — avoid in first trimester).
  • Nevirapine: HEPATOTOXICITY and severe SKIN REACTIONS (Stevens-Johnson syndrome).

3. INTEGRASE STRAND TRANSFER INHIBITORS (INSTIs) — Currently PREFERRED First-Line:

• Mechanism: Block the integrase enzyme, preventing viral DNA from inserting into the host cell's DNA.
• Examples: Dolutegravir (DTG), Raltegravir (RAL), Bictegravir.
• Generally well tolerated; dolutegravir-based regimens are the WHO-recommended and DOH-adopted first-line regimen.
• Note: Dolutegravir may cause neural tube defects if taken in early pregnancy — counseling required.

4. PROTEASE INHIBITORS (PIs):

• Mechanism: Block the protease enzyme, preventing viral maturation — immature, non-infectious virions are produced.
• Examples: Lopinavir/ritonavir (LPV/r), Atazanavir (ATV), Darunavir.
• Often boosted with ritonavir (RTV) to increase blood levels.
• KEY SIDE EFFECTS: GI intolerance (nausea, diarrhea), LIPODYSTROPHY (fat redistribution — buffalo hump, abdominal obesity, facial wasting), hyperlipidemia, hyperglycemia, HEPATOTOXICITY.
• GRAPEFRUIT JUICE significantly increases PI blood levels — AVOID.

5. ENTRY/FUSION INHIBITORS:

• Examples: Maraviroc (CCR5 antagonist — blocks viral entry), Enfuvirtide (fusion inhibitor).
• Used for treatment-experienced patients with drug-resistant virus.

PRINCIPLES OF ADHERENCE (the most NLE-tested ART concept):

• STRICT ADHERENCE is non-negotiable — at least 95% adherence is required to maintain viral suppression.
• Missing doses allows HIV to replicate, mutate, and develop resistance → treatment failure → need for more expensive second-line or third-line regimens.

• Adherence counseling strategies:

  • Simplify regimen (once-daily dosing, fixed-dose combinations)
  • Use pill organizers and alarm reminders
  • Involve family support (with patient consent)
  • Address side effects proactively
  • Understand patient's lifestyle, work schedule, and potential barriers
  • Non-judgmental, patient-centered approach

GENERAL NURSING CONSIDERATIONS FOR ART:

• Monitor CD4 count and viral load at baseline, 3 months, 6 months, then every 6 months when stable.
• Monitor for drug-specific toxicities (CBC for AZT, renal function for TDF, LFTs for NVP/EFV, blood glucose and lipids for PIs).
• Educate about drug interactions — ART drugs interact widely with common medications (rifampicin reduces ART levels; do not take with certain antacids).
• Grapefruit juice interaction with protease inhibitors — AVOID.
• Women of childbearing age: discuss contraception and PMTCT; adjust regimen for pregnancy.

POST-EXPOSURE PROPHYLAXIS (PEP):

• WHAT: Short-course ART taken AFTER a potential HIV exposure to prevent infection.
• WHEN TO START: Within 72 HOURS of exposure — the sooner the better; ideally within 2 hours. After 72 hours, PEP is NOT recommended (window of opportunity has passed).
• DURATION: 28 days of combination ART.
• INDICATIONS: Occupational exposure (needlestick, blood splash to mucous membranes), sexual assault, high-risk consensual sexual exposure.
• Nursing responsibility: After needlestick — (1) Wash with soap and water immediately; (2) Report to supervisor/infection control; (3) Evaluate source patient if possible; (4) Initiate PEP discussion within 72 hours; (5) HIV testing at baseline, 6 weeks, 3 months, and 6 months.

PRE-EXPOSURE PROPHYLAXIS (PrEP):

• WHAT: Daily ART taken by HIV-NEGATIVE individuals at HIGH RISK of HIV exposure.
• Standard regimen: Tenofovir/emtricitabine (TDF/FTC) once daily.
• Highly effective (>99% when taken consistently).
• DOH now provides PrEP through HIV Treatment Hubs for eligible high-risk individuals.
• Requires regular (every 3-month) HIV testing, renal function monitoring, and adherence counseling.

PREVENTION OF MOTHER-TO-CHILD TRANSMISSION (PMTCT):

• HIV can be transmitted from mother to child: during PREGNANCY (transplacentally), DELIVERY (birth canal), and BREASTFEEDING.

• INTERVENTIONS:

  • ART for the mother throughout pregnancy, labor, and delivery.
  • Preferred mode of delivery: Discuss with OB-GYN (C-section may reduce transmission risk in certain situations).
  • Infant prophylaxis: Nevirapine syrup given to the newborn for 6 weeks after birth.
  • AVOID BREASTFEEDING where safe replacement feeding (formula) is accessible and affordable — breastfeeding can transmit HIV.
  • HIV testing of the infant.
• The goal is to reduce mother-to-child transmission to near ZERO.
• Under RA 11166, routine opt-out HIV testing is recommended for all pregnant women.

HIV TRANSMISSION:
HIV is present in sufficient concentrations to cause infection in FOUR main body fluids:

1. BLOOD (including blood products and organs)
2. SEMEN and pre-seminal fluid
3. VAGINAL and RECTAL secretions
4. BREAST MILK

ROUTES OF TRANSMISSION:

• SEXUAL CONTACT: Unprotected anal, vaginal, or oral sex (anal receptive sex carries the highest per-act risk).
• BLOOD-TO-BLOOD: Sharing needles/syringes (intravenous drug use), blood transfusions with unscreened blood (rare in PH with current blood banking protocols), accidental needlestick in healthcare settings.
• PERINATAL (mother-to-child): During pregnancy, labor/delivery, and breastfeeding.

HIV IS NOT TRANSMITTED BY:

• Casual contact (hugging, handshaking)
• Sharing utensils, plates, glasses
• Coughing, sneezing, or airborne droplets
• Mosquito or insect bites (the virus does not survive or replicate in insects)
• Toilet seats, swimming pools
• Saliva, tears, sweat (in insignificant concentrations)
• Being in the same room, home, or workplace

This is critical to teach to reduce STIGMA and DISCRIMINATION, which are major barriers to HIV testing and care in the Philippines.

STANDARD (UNIVERSAL) PRECAUTIONS:
Standard precautions, formerly called universal precautions, are based on the principle that ALL blood and ALL body fluids from EVERY patient should be treated as potentially infectious — regardless of diagnosis, appearance, or HIV status. This protects both healthcare workers and patients.

COMPONENTS OF STANDARD PRECAUTIONS:

1. HAND HYGIENE — THE SINGLE MOST IMPORTANT MEASURE:

• Wash hands with soap and water or use alcohol-based hand rub before and after every patient contact.
• Always wash with soap and water when hands are visibly soiled or after contact with known pathogens.

2. PERSONAL PROTECTIVE EQUIPMENT (PPE):

• GLOVES: Wear when touching blood, body fluids, mucous membranes, or non-intact skin.
• GOWN: Wear when splashing or soiling of clothing is likely.
• MASK + EYE PROTECTION (goggles or face shield): Wear when splashing to the face/eyes is likely (e.g., during procedures, suctioning, delivery).
• Change PPE between patients; remove in correct sequence to avoid self-contamination.

3. SHARPS SAFETY:

• NEVER recap needles using two-handed technique — use one-handed scoop method if recapping is absolutely necessary, but ideally USE SAFETY-ENGINEERED DEVICES and discard directly.
• Dispose of used needles and sharps immediately in a puncture-proof, leak-proof sharps container (sharps box/biohazard container).
• Do not overfill sharps containers (fill to 3/4 capacity maximum).
• Never bend, break, or manipulate used needles.

4. ENVIRONMENTAL CONTROL:

• Clean and disinfect surfaces contaminated with blood/body fluids promptly with appropriate disinfectant (diluted bleach 1:10 for large spills).
• Handle, transport, and process laboratory specimens in labeled, leak-proof containers.

5. SAFE INJECTION PRACTICES:

• Use single-dose vials when possible; never reuse needles or syringes.

POST-NEEDLESTICK PROTOCOL:

1. Do NOT squeeze or suck the wound.
2. Wash immediately with soap and running water (eyes: flush with copious water or saline).
3. Report to supervisor and complete incident report.
4. Evaluate source patient (with consent, if possible) for HIV, HBV, HCV.
5. Assess baseline HIV, HBV, HCV status of exposed worker.
6. Initiate PEP within 72 hours if indicated.
7. Follow-up testing at 6 weeks, 3 months, and 6 months.

RA 11166 — PHILIPPINE HIV AND AIDS POLICY ACT OF 2018:
RA 11166 replaced and expanded upon the older RA 8504. It is the governing law for HIV/AIDS policy in the Philippines and shapes nursing practice profoundly.

KEY PROVISIONS:

1. CONFIDENTIALITY:

• HIV-related information (test results, medical records, treatment history) is STRICTLY CONFIDENTIAL.
• Unauthorized disclosure of a person's HIV status is a CRIMINAL OFFENSE under the law.
• Information may be disclosed only with written, informed consent of the person, OR in strictly defined legal or medical necessity circumstances.
• Healthcare workers who violate confidentiality face criminal penalties.

2. NON-DISCRIMINATION:

• Discrimination against PLHIV (people living with HIV) in EMPLOYMENT, EDUCATION, HEALTHCARE, TRAVEL, and other areas is PROHIBITED.
• Hospitals and clinics CANNOT refuse to treat or admit a patient based on HIV status.
• This is relevant to nursing practice under RA 9173 — the Nursing Act requires nurses to provide care without discrimination.

3. VOLUNTARY HIV COUNSELING AND TESTING:

• HIV testing must be VOLUNTARY and accompanied by PRE-TEST and POST-TEST counseling.
• The law LOWERED THE AGE OF CONSENT for HIV testing to 15 YEARS — minors aged 15 and above can consent to HIV testing independently without parental consent.
• Minors under 15 may still be tested with certain conditions.

4. ACCESS TO TREATMENT AND CARE:

• The state shall ensure access to quality ART, OI treatment, and prophylaxis.
• Social Hygiene Clinics (SHCs) provide free HIV testing and counseling nationwide.
• DOH HIV Treatment Hubs provide free ART.

5. PHILIPPINE NATIONAL AIDS COUNCIL (PNAC):

• RA 11166 establishes and strengthens PNAC as the coordinating body for HIV/AIDS programs across all sectors.

6. KEY POPULATIONS:

• The law recognizes that certain groups are at higher risk: men who have sex with men (MSM), transgender individuals, sex workers, persons who inject drugs (PWID), and their sexual partners.
• Programs are directed at reaching these key populations with non-judgmental, rights-based services.

NURSING OBLIGATIONS UNDER RA 11166 AND RA 9173:

• Maintain strict confidentiality of HIV-related information.
• Provide non-judgmental, compassionate care — nurses must not refuse to care for PLHIV.
• Conduct pre-test and post-test counseling as part of HIV testing services.
• Counsel on prevention: consistent condom use, sterile needles, safe blood practices, PMTCT.
• Support treatment adherence and disclosure decisions.
• Know the DOH referral pathway for ART and OI management.

Organ transplantation requires lifelong immunosuppression to prevent the recipient's immune system from recognizing and destroying the transplanted organ (rejection). The major challenge is achieving sufficient suppression to protect the graft while minimizing the resulting risk of serious infection and malignancy.

TYPES OF REJECTION:

1. HYPERACUTE REJECTION:

• Occurs within MINUTES TO HOURS of transplantation.
• Caused by PREFORMED antibodies (Type II hypersensitivity — antibody-mediated cytotoxicity) against donor antigens.
• The graft turns pale, mottled, and becomes non-functional almost immediately.
• IRREVERSIBLE — requires immediate surgical removal of the graft.
• Prevention: Careful crossmatch testing before transplant.

2. ACUTE REJECTION:

• Occurs DAYS TO MONTHS after transplantation.
• Caused by T cell-mediated (Type IV) immune response to donor HLA antigens.
• Signs: Fever, graft tenderness, decreased function (e.g., rising creatinine for kidney transplant, elevated liver enzymes for liver transplant).
• POTENTIALLY REVERSIBLE with aggressive immunosuppression (high-dose corticosteroids, antithymocyte globulin).

3. CHRONIC REJECTION:

• Occurs MONTHS TO YEARS after transplantation.
• Gradual, progressive fibrosis and loss of graft function due to ongoing immune and inflammatory processes.
• IRREVERSIBLE — the graft eventually fails.
• Managed by optimizing immunosuppression and managing contributing factors.

IMMUNOSUPPRESSIVE DRUG CLASSES:

1. CALCINEURIN INHIBITORS (CNIs) — CORNERSTONE:

• Cyclosporine (Sandimmune) and Tacrolimus (FK506, Prograf).
• Mechanism: Inhibit calcineurin, a phosphatase that activates T cell IL-2 production, thereby suppressing T cell-mediated rejection.
• THERAPEUTIC DRUG MONITORING: Blood levels must be measured regularly — too low = rejection risk; too high = toxicity.

• KEY SIDE EFFECTS:

  • Both: NEPHROTOXICITY (dose-dependent), hypertension, increased infection risk, increased malignancy risk.
  • Cyclosporine-specific: Gingival hyperplasia (gum overgrowth — requires dental care), hirsutism (excess hair growth), tremor.
  • Tacrolimus-specific: Neurotoxicity (tremor, headache, peripheral neuropathy), more potent than cyclosporine, glucose intolerance/new-onset diabetes.
• DRUG INTERACTION: GRAPEFRUIT JUICE significantly increases CNI blood levels (inhibits CYP3A4) — STRICTLY AVOID.

2. ANTIPROLIFERATIVES:

• Mycophenolate mofetil (MMF, CellCept) and Azathioprine (Imuran).
• Mechanism: Inhibit purine synthesis, suppressing lymphocyte proliferation.
• KEY SIDE EFFECTS: Bone marrow suppression (leukopenia, anemia, thrombocytopenia), GI effects (nausea, diarrhea, abdominal pain). Monitor CBC regularly.
• Mycophenolate is TERATOGENIC — women of childbearing age must use effective contraception.

3. CORTICOSTEROIDS:

• Prednisone, methylprednisolone.
• Used for maintenance and for treating acute rejection episodes.
• KEY SIDE EFFECTS: Infection risk, hyperglycemia, hypertension, osteoporosis, Cushing's features, poor wound healing.
• NEVER STOP ABRUPTLY — taper.

4. mTOR INHIBITORS:

• Sirolimus (Rapamune), Everolimus.
• Mechanism: Inhibit mTOR, blocking T and B cell proliferation.
• Side effects: Poor wound healing (delay initiation post-surgery), hyperlipidemia, mouth ulcers, pneumonitis.

5. BIOLOGIC AGENTS:

• Basiliximab (anti-IL-2 receptor monoclonal antibody) — induction agent.
• Antithymocyte globulin (ATG) — for induction and acute rejection treatment.

PRIORITY NURSING INTERVENTIONS FOR TRANSPLANT PATIENTS:

1. INFECTION PREVENTION — THE TOP PRIORITY:

• Immunosuppression predisposes to bacterial, viral (especially CMV, EBV), fungal, and opportunistic infections.
• Strict hand hygiene; limit visitors with infections; private room.
• Monitor temperature vigilantly — STEROIDS MAY MASK FEVER, making early detection harder.
• Any fever in a transplant patient is a MEDICAL EMERGENCY until proven otherwise.
• Regular monitoring for signs of CMV infection (a major post-transplant threat).

2. DRUG MONITORING:

• Trough drug levels (drawn just before the next dose) for cyclosporine and tacrolimus at every clinic visit.
• CBC, renal function, LFTs, glucose, and lipids as per monitoring protocol.

3. GRAFT MONITORING:

• Kidney: Monitor creatinine, urine output, I&O, daily weight, edema.
• Liver: Monitor LFTs, PT/INR, bilirubin.
• Report early signs of rejection promptly.

4. ADHERENCE:

• Lifelong adherence to immunosuppressants is essential — even one missed dose can trigger rejection.
• Educate patient and family about the critical importance of medication adherence.

5. AVOID LIVE VACCINES:

• Live attenuated vaccines (MMR, varicella, yellow fever, oral typhoid) are CONTRAINDICATED in immunosuppressed transplant recipients — they can cause disseminated infection.
• Inactivated/killed vaccines (influenza, pneumococcal, hepatitis B) are safe and recommended.

6. LIFESTYLE MODIFICATIONS:

• Avoid grapefruit and grapefruit juice (drug interaction with CNIs and PIs).
• Sun protection (increased skin cancer risk with immunosuppression).
• Regular skin cancer screening.
• Good dental hygiene (especially for cyclosporine patients with gingival hyperplasia).