HIV/AIDS

Clinical Significance and FNP Practice Models

Human Immunodeficiency Virus (HIV) is a retrovirus that attacks CD4+ T lymphocytes, leading to progressive immune dysfunction. Without treatment, it can progress to Acquired Immunodeficiency Syndrome (AIDS). For the FNP, understanding HIV screening, prevention, diagnosis, and management is critical for reducing transmission and improving patient outcomes. This topic is high-yield for certification exams due to evolving guidelines and the need for primary care–based PrEP (pre-exposure prophylaxis) and ART (antiretroviral therapy) initiation.

Why This Matters Clinically and on Exams

  • HIV is now a chronic, manageable condition; FNPs play a central role in routine screening and co-management with infectious disease specialists.[1]
  • Exam questions often focus on when to start ART, interpretation of lab values, prophylaxis for opportunistic infections (OIs), and prevention strategies (PrEP/PEP).
  • Updates from the CDC and DHHS guidelines are frequently tested.

Essential Terminology and Lab Value Benchmarks

  • HIV (Human Immunodeficiency Virus) – a lentivirus that infects CD4+ helper T cells, macrophages, and dendritic cells.
  • AIDS (Acquired Immunodeficiency Syndrome) – the most advanced stage of HIV infection, defined by a CD4 count <200 cells/µL or the presence of an AIDS-defining opportunistic infection (e.g., Pneumocystis jirovecii pneumonia, Kaposi sarcoma).[2]
  • Viral Load (HIV RNA) – measures the amount of virus in blood; used to monitor treatment response. Goals: undetectable (<20–50 copies/mL depending on assay).
  • CD4 Count – measures immune function; normal range 500–1500 cells/µL. A count <200 indicates severe immunosuppression and increased risk for OIs.
  • ART (Antiretroviral Therapy) – combination therapy typically using two NRTIs plus a third agent (INSTI, NNRTI, or protease inhibitor).[1]
  • PrEP (Pre-Exposure Prophylaxis) – daily or event-driven oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) or injectable cabotegravir to prevent HIV in high-risk individuals.[3]
  • PEP (Post-Exposure Prophylaxis) – 28-day course of ART started within 72 hours of a high-risk exposure (e.g., needlestick, unprotected sexual contact).[3]
  • Seroconversion – development of detectable HIV antibodies, usually 2–6 weeks after infection; may coincide with acute retroviral syndrome.

Transmission Dynamics, Staging, and Diagnostic Algorithms

HIV Transmission

  • Blood, semen, vaginal/rectal fluids, breast milk.
  • Not transmitted via casual contact, saliva, tears, or insects.
  • Highest risk: receptive anal intercourse, sharing needles, vertical transmission (mother-to-child).

Disease Progression (if untreated)

  1. Acute HIV Infection (Stage 1) – occurs 2–4 weeks after exposure; symptoms mimic mononucleosis or influenza. High viral load, p24 antigen detectable, antibody test may still be negative.
  2. Chronic HIV Infection (Stage 2) – asymptomatic period lasting years; virus actively replicates; gradual CD4 decline.
  3. AIDS (Stage 3) – CD4 <200 or AIDS-defining illness; high risk of OIs and malignancies.

HIV Screening and Diagnosis

  • CDC recommends routine, opt-out screening for all patients aged 13–64 in healthcare settings.[4]
  • Repeat testing at least annually for those at high risk (MSM, IV drug users, partners of HIV+ individuals).
  • Diagnosis algorithm[4]:
    1. Initial 4th-generation HIV-1/2 antigen/antibody immunoassay (detects p24 antigen + antibodies).
    2. If reactive, follow with HIV-1/HIV-2 antibody differentiation test.
    3. If differentiation test is negative/indeterminate, perform HIV-1 nucleic acid test (NAT) to rule out acute infection.
  • Window period: 4th-generation tests can detect infection 2–4 weeks after exposure; NAT can detect as early as 10 days.

Acute to Chronic: Clinical Presentation Spectrum

Acute Retroviral Syndrome

  • Fever, fatigue, myalgia, sore throat, lymphadenopathy.
  • Maculopapular rash on trunk, face, or extremities.
  • Mucosal ulcers (oral, genital).
  • Headache, nausea, diarrhea.
  • Lasts 1–2 weeks; many patients do not seek care.

Chronic HIV: Common Findings

  • Persistent generalized lymphadenopathy (PGL).
  • Oral hairy leukoplakia, thrush (oral candidiasis).
  • Herpes zoster (shingles).
  • Unexplained weight loss, night sweats, chronic diarrhea.
  • Idiopathic thrombocytopenic purpura (ITP).

AIDS-Defining Opportunistic Infections (Key for exams)

  • Pneumocystis jirovecii pneumonia (PCP) – CD4 <200; subacute onset of dyspnea, fever, dry cough; bilateral interstitial infiltrates on CXR; treat with TMP-SMX.
  • Mycobacterium avium complex (MAC) – CD4 <50; disseminated infection with fever, night sweats, weight loss, anemia.
  • Cytomegalovirus (CMV) retinitis – CD4 <50; painless vision loss; "cotton wool" spots on fundoscopy.
  • Cerebral toxoplasmosis – CD4 <100; ring-enhancing brain lesions on MRI.
  • Cryptococcal meningitis – CD4 <100; headache, fever, altered mental status; treat with amphotericin B + flucytosine.
  • Kaposi sarcoma – HHV-8 associated; purple/red skin lesions; can involve viscera.

Initial Evaluation and Longitudinal Monitoring

Initial Evaluation of a Newly Diagnosed HIV Patient

  • Confirm diagnosis with repeat testing or NAT.
  • Obtain baseline labs:
    • CD4 count and percentage.
    • HIV viral load (plasma RNA).
    • HIV genotype for resistance testing (mandatory before starting ART).[1]
    • HLA-B*5701 screening (risk of abacavir hypersensitivity).
    • Baseline CBC, CMP, lipid panel, glucose, hepatitis B/C serologies, TB screening, STI testing.
  • Assess for OI symptoms, immunization status, social support, and adherence barriers.

Ongoing Monitoring

  • Viral load – every 3–6 months (or within 4–6 weeks after initiating/changing ART). Target: undetectable.
  • CD4 count – every 3–6 months once stable, then every 6–12 months if on ART with suppressed viral load and CD4 >300.
  • Resistance testing – if virologic failure (viral load >200 copies/mL after 24 weeks of therapy).
  • Screen for comorbidities: cardiovascular risk (Framingham), bone density (DEXA), renal function (especially if on tenofovir), and mental health annually.

Antiretroviral Regimens and Prophylactic Care Models

Antiretroviral Therapy (ART)

  • ART should be initiated in all HIV-infected individuals regardless of CD4 count, as soon as possible after diagnosis (usually within 7–14 days).[1]
  • Preferred initial regimens (per DHHS 2025 guidelines):
    • Two NRTIs + an INSTI: e.g., bictegravir/emtricitabine/tenofovir alafenamide (Bic/FTC/TAF) – single tablet regimen.
    • Alternatives: dolutegravir (DTG) + FTC/TAF, or raltegravir + FTC/TDF.
  • Monitor for side effects: renal toxicity (TDF), neuropsychiatric effects (DTG), weight gain (INSTIs).
  • DO NOT use zidovudine (AZT) with stavudine due to high toxicity.

Prevention of Opportunistic Infections

  • Primary prophylaxis (start when CD4 below threshold):
    • CD4 <200: TMP-SMX one double-strength daily (PCP).
    • CD4 <100: azithromycin 1200 mg weekly (MAC).
    • CD4 <50: consider CMV prophylaxis (valganciclovir) if CMV IgG+.
  • Secondary prophylaxis – continues until CD4 rises above threshold for ≥3–6 months on ART.
  • Vaccinations: pneumococcal (PCV15/20 + PPSV23), influenza, hepatitis A/B, HPV, Tdap. Avoid live vaccines (MMR, varicella) if CD4 <200.

PrEP and PEP (Prevention for High-Risk Patients)

  • PrEP:
    • Oral TDF/FTC (Truvada) once daily for men and women with ongoing risk.
    • Oral TAF/FTC (Descovy) for men and transgender women (not for cisgender women due to limited data).
    • Long-acting injectable cabotegravir every 2 months (highly effective).[3]
    • Screen for HIV (4th-gen assay), renal function, hepatitis B before starting, then every 3 months.
  • PEP:
    • Initiate within 72 hours (best within 1–2 hours). Duration 28 days.
    • Regimen: TDF/FTC (or TAF/FTC) + raltegravir or dolutegravir.
    • Follow-up HIV test at 4–6 weeks and 3 months.[3]

Adverse Effect Profiles and Drug Interaction Safety

ART Adverse Effects (Commonly Tested)

  • Tenofovir (TDF): renal tubular toxicity, Fanconi syndrome, decreased bone mineral density.
  • Abacavir: hypersensitivity reaction (fever, rash, GI upset) – screen HLA-B*5701; DO NOT rechallenge.
  • Efavirenz: CNS side effects (vivid dreams, dizziness), teratogenic (avoid in pregnancy).
  • Protease inhibitors (e.g., atazanavir, darunavir): hyperbilirubinemia (atazanavir), GI intolerance, metabolic syndrome, drug interactions (CYP3A4).
  • Integrase inhibitors (e.g., dolutegravir): weight gain, insomnia, headache; rare hypersensitivity.

Drug Interactions – Critical for FNP Role

  • Protease inhibitors and cobicistat inhibit CYP3A4 – contraindicated with statins (except atorvastatin limited dose, rosuvastatin low dose).
  • Do not use rifampin with protease inhibitors or most NNRTIs (except efavirenz).
  • Methadone doses may need adjustment with certain ARTs (e.g., efavirenz increases methadone clearance).
  • Check antacid timing: calcium/magnesium/aluminum antacids bind raltegravir (separate by 2 hours).

Complications of Untreated HIV/AIDS

  • Opportunistic infections (as above).
  • HIV-associated neurocognitive disorder (HAND).
  • Wasting syndrome, cardiomyopathy, nephropathy (HIVAN – collapsing glomerulopathy).
  • Increased risk of malignancies: non-Hodgkin lymphoma, cervical cancer, anal cancer (HPV co-infection).

Clinical Reasoning and Exam-Prep Pearls

  • First step for all pregnant women: offer HIV testing (opt-out). If HIV+, start ART regardless of CD4; zidovudine IV during labor, and give infant ART for 4–6 weeks. Breastfeeding is contraindicated in the US.[1]
  • HIV resistance testing must be done before starting ART; do not wait for results more than 2 weeks to initiate therapy.
  • When CD4 <200 – give PCP prophylaxis (TMP-SMX). Also check for toxoplasma IgG; if positive, give TMP-SMX also covers toxoplasma.
  • Viral load “blip” (single detectable 50–200 copies/mL with subsequent suppression) – no need to change therapy.
  • Confirmed virologic failure (viral load >200 copies/mL on two consecutive measures after 24 weeks on ART) – order resistance testing and switch regimen.
  • Needlestick PEP: start within 72 hours, use 3-drug regimen for 28 days, follow-up testing at 4 weeks and 3 months.[3]
  • Undetectable = Untransmittable (U=U) – patients with consistent viral load <200 copies/mL have effectively zero risk of sexual transmission. Emphasize adherence.
  • Memory aid for OIs by CD4 count:
    • <200: PCP (Pneumocystis).
    • <100: T (Toxoplasma), MAC (Mycobacterium avium complex), C (Cryptococcus).
    • <50: C (CMV), M (MAC also covered above).
  • Always screen for hepatitis B and C, TB (IGRA), and STIs at initial visit and periodically.
  • FNP must counsel patients on adherence strategies: pillboxes, alarm apps, long-acting injectables (cabotegravir/rilpivirine) for those with adherence challenges.

References

  1. Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the Use of Antiretroviral Agents in Adults and Adolescents with HIV. Department of Health and Human Services (DHHS). Updated December 18, 2024. Accessed June 2025. https://clinicalinfo.hiv.gov/en/guidelines/adult-and-adolescent-arv
  2. Centers for Disease Control and Prevention. Revised Surveillance Case Definitions for HIV Infection. MMWR 2014;63(RR-03):1–10. https://www.cdc.gov/mmwr/preview/mmwrhtml/rr6303a1.htm
  3. Centers for Disease Control and Prevention. Preexposure Prophylaxis for the Prevention of HIV Infection in the United States – 2021 Update: A Clinical Practice Guideline. http://stacks.cdc.gov/view/cdc/112360
  4. Branson BM, Handsfield HH, Lampe MA, et al. Revised Recommendations for HIV Testing of Adults, Adolescents, and Pregnant Women in Health-Care Settings. MMWR 2006;55(RR-14):1–17. https://pubmed.ncbi.nlm.nih.gov/16988643/
  5. Lewis SL, Bucher L, Heitkemper MM, Dirksen SR. Medical-Surgical Nursing: Assessment and Management of Clinical Problems. 11th ed. Elsevier; 2021. Chapter 53: Nursing Management of Patients with HIV/AIDS.
  6. U.S. Preventive Services Task Force. Human Immunodeficiency Virus (HIV) Infection: Screening. Final Recommendation Statement. June 2019. https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/human-immunodeficiency-virus-hiv-infection-screening

Ready to test your knowledge?

Master the core responsibilities, scope of practice, and limitations for the Family Nurse Practitioner exam.

Start Practice Questions
Previous Topic Next Topic