HIV Medicine and Sexually Transmitted Infections
Core concepts
Know ART: integrase inhibitors (dolutegravir, bictegravir) are preferred first-line; NRTIs (tenofovir, emtricitabine); NNRTIs (efavirenz, rilpivirine); protease inhibitors (darunavir boosted with ritonavir or cobicistat). Start ART in all patients regardless of CD4. Monitor viral load and CD4. Recognize immune reconstitution inflammatory syndrome (IRIS).
Must-know STIs
Syphilis (penicillin G benzathine; neurosyphilis-IV penicillin), gonorrhea (ceftriaxone; test for resistance), chlamydia (doxycycline or azithromycin), trichomonas (metronidazole), HSV (acyclovir), and HPV (vaccine). HIV post-exposure prophylaxis: 28 days of a three-drug regimen, start within 72 hours.
Traps
Don't use efavirenz in pregnancy (neural tube defects historically). Rilpivirine requires acid-avoid PPIs. Drug interactions: rifampin with protease inhibitors. Syphilis serology interpretation-treponemal vs nontreponemal tests. Gonorrhea resistance-ceftriaxone is first-line.
Worked rule of thumb
For a patient with HIV and a CD4 count of 50 with fever and lymphadenopathy, think disseminated MAC or TB. Start ART but be alert for IRIS; treat opportunistic infections first when indicated.