HIV and Retroviral therapy

human immunodeficiency virus (HIV)

Retrovirus that CD4 T helper cells, dendritic cells, and monocytes resulting in a decline in CD4 T cells below threshold needed to support cell mediated immunity. Allows the body to become more susceptible to opportunistic infections and cancer. Discovered in 1983.

AIDS (acquired immune deficiency syndrome)

Outcome of chronic HIV infection and consequent depletion of CD4 T cells. Defines as CD4 count <200 cells/microL or the presence of any AIDS defining condition regardless of CD4 count. Term defined in 1982.

increased, decreasing

The prevalence of HIV has _____ due to patients living longer but the number of newly diagnosed infections is _____ due to safer sex education.

HIV populations most at risk

- Homosexual men

- Transgenders

- IV drug users

- Sex workers

- Heterosexual spread (worldwide)

HIV transmission

- Blood

- Semen (pre-seminal fluid)

- Rectal fluids

- Vaginal fluids

- Breast milk

*NOT saliva, sweat, tears, vomit, urine, nasal secretions*

Acute retroviral syndrome

Occurs 1-6 weeks after HIV exposure in 50-70% of infected individuals; similar to mono. Spontaneous resolution. Infection latent until progresses to AIDS.

Labs for HIV

- HIV test

- CBC

- CMP

- UA

- STI screening

HIV tests

- 4th generation antigen/antibody combination HIV 1/2 immunoassay

- HIV ELISA (screen, check @ 6 wks AND 6 mos.)

- Western Blot (Confirms)

- Absolute CD4 Lymphocyte (<200 = AIDS)

- CD4 lymphocyte percentage (<14% = AIDS)

- HIV viral load (this will show it first)

- HIV rapid antibody test (10-20 mins)

72 hrs

Postexposure prophylaxis is available ______ after exposure

Tenofovir

Pill approved by the FDA for daily use as prophylaxis for people at very high risk of getting HIV infection.

Zidovudine (AZT)

Given to infants born from HIV positive mothers. Also advised NOT to breastfeed.

HIV antiretroviral therapy

- Triple drug therapy approved in 2018

- New 2 drug therapy given once daily as of April 2019

Tuberculosis

Found in 5% all HIV positive patients in the U.S. Annual PPD testing needed. Positive = >5mm induration. If positive, CXR needed. Consider inerferon gamma release assay if PPD negative and suspicion is high.

Syphilis

Increase incidence among MSM. Should be screened using RPR or VRDL every 6 mos. Any positive test confirmed with treponemal antibody testing. Treat with PCN.

Stages of HIV infection

Phase 1: (Transmission) asymptomatic or chronic lymphadenopathy

Phase 2: (Acute) symptomatic; early indications of immune failure

Phase 3: (Chronic) AIDS indicator conditions

antiretroviral therapy

All patients positive for HIV should be offered _____ regardless of their CD4 count. Monitor CD4 counts and HIV viral load every 3-6 months.

Advanced HIV infection

Defined as CD4 count <50 cells/microL

Mucocutaneous candidiasis

Oral is common. Complain of unpleasant taste or dryness in mouth. Pseudomembranous or erythematous. Fungal rashes also common. Treated with Clotrimazole or Fluconazole.

Oral Hairy Leukoplakia

Caused by Epstein Barr virus, white patches on side (lateral edges) of tongue that resemble hair. Resolved with antiretroviral therapy.

genital herpes

Sexually transmitted disease caused by the herpes simplex type II virus.

herpes zoster (shingles)

Common manifestation of HIV. Painful lesions along dermatome. Vaccine available.

Molluscum contagiosum

Caused by pox virus. Common in HIV infected adults. Umbilicated fleshy papules. Treated topically with liquid nitrogen.

community acquired pneumonia

Most common cause of pulmonary disease in HIV patients. Caused by pneumococcal pneumonia, H. flu, pseudomonas.

Pneumocystic jiroveci pneumonia

Most common opportunistic infection with AIDS. Fungal in origin. AIDS defining condition. Fever, cough, dyspnea, and hypoxemia. CXR shows diffuse or perihilar infiltrates. Dx through Wright-Giemsa sputum stain. LDH elevated in 95% of patients. Positive serum beta glucan test. Treated and prophylaxed @ CD4 <200 with BACTRIM.

Esophageal Candidiasis

Common AIDS complication/AIDS defining condition. Dysphagia or difficulty swallowing. Commonly dx by EGD. Treated with Flucanazole

Kaposi's sarcoma

AIDS defining condition. Caused by HHV8. Purplish non blanching lesions. Lesions appear everywhere. Resolve with effective ART. May flare as part of IRIS.

Wasting syndrome

weight loss, decrease in muscular strength, appetite, and mental activity; associated with AIDS

Mycobacterium avium

Causes secondary infections in AIDS patients. Positive blood culture in 98% but affects multiple organ systems. Treated for at least 12 months with combination therapy while CD4 increases. Common in CD4 <50 cells/microL.

Cryptococcal meningitis

Most common retinal infection in AIDS patients. Retinal perivesicular hemorrhages and white fluffy exudates. Rapidly progressive.

Toxoplasmosis

Causes CNS disease. Most common space occupying lesion in HIV affected patients. HA, focal neuro deficits, altered mental status, seizures. Start prophylaxis at CD4<100

ALL CD4 counts

Prophylaxis for TB should be started at

CD4 <250

Prophylaxis for Coccidiomycosis should be started at ____.

CD4 <200

Prophylaxis for pneumocystitis should be started at _____. D/C @ 400.

CD4 <150

Prophylaxis for Histoplasmosis should be started at

CD4 <100

Prophylaxis for toxoplasmosis and cryptococcus should be started at

CD4 <50

Prophylaxis for mycobacterium avium complex should be started at ____. D/C @ >100 for 3 months.

highly-effective antiretroviral therapy

Combination of 3 medications from at least 2 different classes.

Nucleoside Reverse Transcriptase Inhibitors

drugs that prevent the growth of the viral DNA chain, preventing it from inserting into the host DNA, so viral replication cannot occur. Zidovudine and Tenofovir.

nonnucleoside reverse transcriptase inhibitors

Inhibit reverse transcriptase. Well tolerated. No special monitoring.

Protease inhibitors

Suppress HIV replication. Administered as combo therapy. Metabolized by CYP450 enzymes. Used to boost other regimens.

Entry inhibitors

Block proteins on the CD4 cells that HIV needs to enter the cells. Used as add on therapy for patients with multi drug resistance.

Integrase inhibitors

Slow HIV replication by blocking the HIV integrase enzyme needed for viral replication. Allow for more rapid decrease in viral load.

3-4 months, 1-2 months

Toxicity should be monitored every _____ and CD4/Viral load should be monitored every _____ after HIV treatment regimen has started. (Can go 3-6 mos once stable.

infectious disease specialist

All AIDS patients should be referred to a