HIV CD4 <200, dry cough, exertional hypoxia, ↑LDH, bilateral interstitial
Order: CD4, LDH (normal LDH strongly excludes PCP), ABG
Treat: TMP-SMX IV/PO ×21 d
Add prednisone if: PaO₂ <70 or A-a gradient >35
Prophylaxis: TMP-SMX when CD4 <200
Order set
- CD4, HIV test
- LDH
- ABG (A-a gradient)
- Induced sputum/BAL
- CXR/HRCT
Criteria
AdmitHypoxia / significant disease
ICURespiratory failure
IntubateRefractory hypoxaemia
DischargeOxygenation improved, on TMP-SMX (+steroids), ART + prophylaxis plan
Clinical detail — differentials, red flags, pitfalls, disposition
Red flags
- PaO₂ <70 / large A-a gradient
- Respiratory failure
Differentials
- Bacterial pneumonia
- TB
- Viral pneumonitis
Common mistakes
- Forgetting adjunctive steroids in hypoxia
- Missing other OIs
Disposition & follow-up
TMP-SMX + steroids if hypoxic; start ART; prophylaxis.
Discharge package
MedicationsComplete TMP-SMX; prophylaxis; start/continue ART
Follow-upHIV/ID clinic
Warning symptomsRecurrent breathlessness, fever
💊 Treatment detail — doses & preparation
Co-trimoxazole (TMP-SMX)antibiotic
DosePCP treatment: TMP 15–20 mg/kg/day IV/PO in 3–4 divided doses ×21 d; prophylaxis: 960 mg OD or 480 mg OD
PreparationIV: 480 mg/5 mL ampoule — dilute each 480 mg in 125 mL D5W, infuse over 60–90 min; PO 480/960 mg tablets
MonitorK⁺, creatinine (both rise), rash, marrow; FBC/U&E 2×/wk on high dose
Prednisone (PCP adjunct)corticosteroid
DosePCP with PaO₂ <9.3 kPa: 40 mg BD ×5 d → 40 mg OD ×5 d → 20 mg OD ×11 d (IV methylpred 75% dose if NBM)
PreparationTablets with food
MonitorGlucose; start at same time as TMP-SMX
📖 IDSA / DHHS OIReviewed July 2026