Adult or adolescent with HIV and suspected opportunistic infection (OI)
Most OIs occur at CD4 <200 cells/mm3. Children: use paediatric OI guidelines.
All Pathways
Infectious DiseaseManagement
HIV Opportunistic Infections Management
HIV Opportunistic Infections Management: Adult or adolescent with HIV and suspected opportunistic infection (OI) → Assess severity; check CD4 count and ...
Pathway Overview
16 steps
Algorithm Steps
16 total
01Start 02Action Assess severity; check CD4 count and HIV viral load
Seriously unwell (hypoxia, reduced consciousness, sepsis): start empirical treatment and get ID advice. Do not wait for the CD4 result.
- PCP, oral candidiasis: risk rises at CD4 <200 cells/mm3
- Cryptococcus, oesophageal candidiasis: mostly CD4 <100; toxoplasma: highest risk CD4 <50
- CMV retinitis, disseminated MAC: mostly CD4 <50
- Ask about ART history, adherence, previous OIs, prophylaxis and pregnancy
03Warning Before drugs: check pregnancy, sulfa allergy, G6PD and kidney function
Each changes the drug or the dose; each OI step has its own pregnancy line. Children under 13 years: use paediatric OI guidelines.
- Pregnancy: get ID and obstetric advice. Cryptococcus in 1st trimester: amphotericin B alone, avoid azoles. MAC: azithromycin, not clarithromycin
- Sulfa allergy: TMP-SMX and sulfadiazine need an alternative or specialist desensitisation. Past SJS/TEN or other life-threatening reaction: never rechallenge or desensitise. Test G6PD before primaquine or dapsone
- Kidney impairment: adjust TMP-SMX, flucytosine, ganciclovir, valganciclovir and ethambutol doses
04Action Plan ART start: timing depends on the OI
Cryptococcal or TB meningitis: do NOT start ART early (higher death rate from IRIS). Choose ART with an HIV specialist; check drug interactions.
- PCP, toxoplasmosis, CMV, candidiasis: start ART within 2 weeks of OI treatment
- Disseminated MAC: start ART as soon as possible
- Cryptococcal meningitis: defer ART 4-6 weeks after antifungal start
- TB: CD4 <50 within 2 weeks; higher CD4 within 2-8 weeks. TB meningitis: not before 2 weeks, once meningitis is controlled
- Rifampicin, rifabutin and clarithromycin interact with many ART drugs
05Warning Worsening after ART start: IRIS or treatment failure?
Exclude treatment failure, a new OI, drug toxicity and poor adherence before calling it IRIS.
- IRIS: continue ART and OI treatment in most cases; get specialist advice
- Corticosteroids can help significant IRIS. Avoid them in Kaposi sarcoma (life-threatening flares)
- Cryptococcal IRIS vs relapse: repeat LP with opening pressure and culture
06Action Prophylaxis plan: secondary after each OI, primary by CD4
Apply after OI treatment. Continue secondary prophylaxis (maintenance) after each OI until immune recovery on ART, as set out in each OI step.
- PCP: TMP-SMX 1 DS or 1 SS tablet daily if CD4 <100, or CD4 100-200 with detectable viral load
- Toxoplasma IgG positive and CD4 <100: TMP-SMX 1 DS daily (also covers PCP)
- Stop PCP prophylaxis when CD4 >=200 for >=3 months on ART (consider at CD4 100-200 with undetectable viral load for 3-6 months)
- MAC: no primary prophylaxis if ART starts at once. Only if CD4 <50 and not on suppressive ART: exclude MAC, then azithromycin 1,200 mg weekly
- Cryptococcus: serum CrAg if CD4 <=200 (especially <=50); positive: LP. No fluconazole prophylaxis without a positive CrAg
- CMV: no primary prophylaxis; baseline eye examination if CD4 <100; urgent review for floaters or visual change
07Decision Which opportunistic infection?
Based on presentation and tests. Treat each coexisting OI.
- PCP
08Action Pneumocystis pneumonia (PCP)
Dyspnoea, dry cough, hypoxia, bilateral infiltrates. Test G6PD before primaquine or dapsone. Sulfa allergy: use an alternative.
- Adult, moderate-severe (PaO2 <70 mmHg on room air or A-a gradient >=35 mmHg): TMP-SMX IV, TMP 15-20 mg/kg/day + SMX 75-100 mg/kg/day in divided doses every 6-8 h; oral when improving
- Moderate-severe: add prednisone as soon as possible (ideally within 72 h): 40 mg twice daily days 1-5, 40 mg daily days 6-10, 20 mg daily days 11-21
- Mild-moderate: TMP-SMX 2 DS tablets orally 3 times daily
- Alternatives, severe: primaquine 30 mg (base) daily + clindamycin, or IV pentamidine. Mild: dapsone + trimethoprim, primaquine + clindamycin, or atovaquone 750 mg twice daily with food
- Treat 21 days, then secondary prophylaxis. Start ART within 2 weeks
- Monitor potassium, creatinine and blood count on high-dose TMP-SMX (more hyperkalaemia with kidney impairment, ACE inhibitor or ARB). IV pentamidine: monitor glucose, BP and creatinine
- Pregnancy: TMP-SMX is still first choice, including 1st trimester; avoid primaquine if other options exist
09Outcome Acute treatment complete: secondary prophylaxis until immune recovery on ART
Follow up CD4 and viral load; stop prophylaxis only when the criteria in the OI step are met.
- Cryptococcal meningitis
10Action Cryptococcal meningitis
Headache, fever, confusion. Focal signs, reduced consciousness or seizures: CT or MRI brain before LP. Measure CSF opening pressure at every LP. Do not start ART for 4-6 weeks.
- Adult induction, 2 weeks in hospital: liposomal amphotericin B 3-4 mg/kg IV daily + flucytosine 25 mg/kg orally 4 times daily
- Amphotericin formulations are not interchangeable: conventional (deoxycholate) dose is 0.7-1 mg/kg daily
- Flucytosine not yet available (SAS in Australia): start liposomal amphotericin B + fluconazole 800-1,200 mg daily; add flucytosine when it arrives (specialist advice)
- Raised pressure: daily therapeutic LP until normal. Do not use corticosteroids, acetazolamide or mannitol to lower it
- Consolidation: fluconazole 800 mg daily for >=8 weeks; reduce to 400 mg daily once CSF is sterile and ART has started
- Maintenance: fluconazole 200 mg daily for >=1 year; stop when CD4 >=100 and viral load suppressed on ART
- Adjust flucytosine for kidney function; monitor levels, blood count, potassium, magnesium and creatinine
- Pregnancy, 1st trimester: amphotericin B alone; avoid azoles; add flucytosine only if benefit outweighs risk
- Path rejoins step 09Shared downstream outcome
- Toxoplasmosis
11Action Toxoplasma encephalitis
Ring-enhancing brain lesions, focal deficits. No improvement in 10-14 days or worse in week 1: consider brain biopsy (lymphoma).
- Adult: pyrimethamine 200 mg orally once, then <=60 kg: 50 mg daily + sulfadiazine 1,000 mg every 6 h; >60 kg: 75 mg daily + sulfadiazine 1,500 mg every 6 h
- Give leucovorin (folinic acid) 10-25 mg daily with pyrimethamine
- Or TMP-SMX (TMP 5 mg/kg + SMX 25 mg/kg) IV or orally twice daily; use it if pyrimethamine or sulfadiazine is delayed
- Sulfa allergy: pyrimethamine + leucovorin (doses above) + clindamycin 600 mg IV or orally every 6 h; add separate PCP prophylaxis
- Treat >=6 weeks, then maintenance until CD4 >200 for >6 months on ART. Start ART within 2 weeks
- Dexamethasone only for mass effect or oedema. Antiseizure drugs only if seizures
- Pregnancy: same regimen; for encephalitis the benefit of pyrimethamine outweighs the 1st-trimester risk
- Path rejoins step 09Shared downstream outcome
- CMV
12Action CMV disease (retinitis, colitis, oesophagitis)
Retinitis: urgent ophthalmology review. Adjust ganciclovir and valganciclovir for kidney function; check blood count.
- Retinitis, adult: valganciclovir 900 mg orally every 12 h, or ganciclovir 5 mg/kg IV every 12 h, for 14-21 days; then valganciclovir 900 mg daily
- Sight-threatening lesion (within 1,500 microns of fovea or optic disc): add intravitreal ganciclovir or foscarnet
- Colitis or oesophagitis: ganciclovir 5 mg/kg IV every 12 h, oral valganciclovir when absorbed; 21-42 days
- Stop retinitis maintenance after >=3 months, lesions inactive and CD4 >=100 for >=3 months; then eye review at least every 3 months (relapse, immune recovery uveitis)
- Start ART within 2 weeks
- Pregnancy: valganciclovir is preferred; foscarnet or cidofovir only with maternal-fetal specialist advice
- Path rejoins step 09Shared downstream outcome
- MAC
13Action Disseminated MAC (Mycobacterium avium complex)
Fever, weight loss, anaemia, lymphadenopathy, hepatosplenomegaly. Clarithromycin interacts with many ART drugs.
- Adult: clarithromycin 500 mg orally twice daily + ethambutol 15 mg/kg orally daily
- Azithromycin 500-600 mg daily + ethambutol if clarithromycin interacts or is not tolerated, and in pregnancy
- Severe disease: some experts add rifabutin 300 mg daily (dose depends on ART interactions)
- Treat >=12 months; stop when no symptoms and CD4 >100 for >=6 months on ART
- Start ART as soon as possible
- Path rejoins step 09Shared downstream outcome
- Candidiasis
14Action Oropharyngeal or oesophageal candidiasis
Oesophageal disease needs systemic treatment. No response in 7 days: endoscopy.
- Oropharyngeal: fluconazole 200 mg once, then 100-200 mg orally daily for 7-14 days
- Oesophageal: fluconazole 200 mg once, then 100-200 mg (up to 400 mg) orally or IV daily for 14-21 days
- Refractory: posaconazole, an echinocandin or amphotericin B (specialist advice)
- Pregnancy: topical treatment for oral disease; 1st trimester oesophageal disease: amphotericin B instead of fluconazole
- Path rejoins step 09Shared downstream outcome
- TB
15Action Tuberculosis (active)
Treat with the TB service. Rifampicin and rifabutin interact with many ART drugs.
- ART: CD4 <50 within 2 weeks of TB treatment; higher CD4 within 2-8 weeks
- TB meningitis: do not start ART in the first 2 weeks; start once meningitis is controlled (specialist)
- TB meningitis: adjunctive dexamethasone is still recommended in HIV (dose with the TB service)
- Preventive prednisone for TB-IRIS if starting ART within 30 days, CD4 <=100 and responding to TB treatment: 40 mg daily for 2 weeks, then 20 mg daily for 2 weeks (not in Kaposi sarcoma, rifampicin resistance or active hepatitis B)
- Path rejoins step 09Shared downstream outcome
- Other or unclear
16Action Other, multiple or unclear OI
Get ID advice. Consider HSV, VZV, histoplasmosis, PML, syphilis, lymphoma and bacterial infection. Start ART within 2 weeks for most OIs.
- Path rejoins step 09Shared downstream outcome
Guideline Source
Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents With HIV (NIH, HIVMA, IDSA)
Clinical Safety Information
Clinical Decision Support — Not a Substitute for Clinical Judgment
Individual patient factors may require deviation from these recommendations.
Known Limitations
- Adults and adolescents only. Covers the common OIs; get ID advice for other, multiple or unclear OIs
- Australia: flucytosine and sulfadiazine are not on the ARTG (SAS access); ART choice and drug interactions need an HIV specialist
- Doses are for adults with normal kidney function; weight-based doses have no fixed maximum in the source
- IRIS is common after ART start; distinguishing IRIS from treatment failure needs specialist input
- AI-assisted repair; not yet reviewed by a clinician
Contraindicated Populations
Children under 13 years: use paediatric OI guidelinesPregnancy: drug choices change; get ID and obstetric advice
Applicable Regions
USEUAU
AU: Not on the ARTG (Sep 2026): flucytosine and sulfadiazine; access by SAS. On the ARTG: pyrimethamine (Daraprim 25 mg), primaquine (7.5 mg tablets), IV sulfamethoxazole-trimethoprim, liposomal amphotericin B, pentamidine, atovaquone. Do not delay treatment waiting for SAS drugs: use TMP-SMX for toxoplasmosis.
EU: EACS guidelines are the European reference; check local drug availability.
US: Based on the NIH/HIVMA/IDSA adult and adolescent OI guidelines (sections updated to Sep 2025).
Version 2Next review: 2027-09-30
Next steps
Finish the workflow by opening the most relevant calculator, then convert the session into a live account when you are ready.
Related Resources
Frequently Asked Questions
What is the HIV Opportunistic Infections Management?
The HIV Opportunistic Infections Management is a management clinical algorithm for Infectious Disease. It provides a structured decision tree to guide clinical decision-making, based on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents With HIV (NIH, HIVMA, IDSA).
What guideline is the HIV Opportunistic Infections Management based on?
This algorithm is based on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents With HIV (NIH, HIVMA, IDSA).
What are the limitations of the HIV Opportunistic Infections Management?
Known limitations include: Adults and adolescents only. Covers the common OIs; get ID advice for other, multiple or unclear OIs; Australia: flucytosine and sulfadiazine are not on the ARTG (SAS access); ART choice and drug interactions need an HIV specialist; Doses are for adults with normal kidney function; weight-based doses have no fixed maximum in the source; IRIS is common after ART start; distinguishing IRIS from treatment failure needs specialist input; AI-assisted repair; not yet reviewed by a clinician. Individual patient factors may require deviation from these recommendations.
Get AI-Powered Analysis Alongside This Algorithm
In AttendMe.ai, the HIV Opportunistic Infections Management appears automatically when your clinical question matches — alongside evidence from 3M+ peer-reviewed articles.
Try AttendMe Free