A 32 year old Gay man is admitted with a three month history of weight loss, fatigue, intermittent fever and lymphadenopathy. One month ago he developed progressively increasing diarrhea and had experienced severe shortness of breath and a non productive cough for three days. His chest X-ray reveals a diffuse interstitial infiltrate. His temperature is 102 o F his CD4 count is 180. A bronchoscopy and transbronchial lung biopsy is performed

* other major causes of pulmonary infiltrates include mycobacterial infections, fungal infections, nonspecific interstitial pneumonitis, Kaposi’s Sarcoma, and lymphoma. * other major causes of pulmonary infiltrates include mycobacterial infections, fungal infections, nonspecific interstitial pneumonitis, Kaposi’s Sarcoma, and lymphoma. What are the most likely infectious agents causing this pneumonia? Parasitic - Pneumocystis carinii Bacterial –Streptococcal Pneumoniae,Hemophilus Influenza

What are the therapeutic options for each agent ? Pneumocystis Carinii is treated with First line Regimen 1. Trimethoprim/sulfamethoxazole (TMP/SMX) 15-20mg/kg/day of TMP and mg/kg/day of SMX 15-20mg/kg/day of TMP and mg/kg/day of SMX 2. Intravenous or IM Pentamidine for treatment of PCP. Aerosolized Pentamidine used for prophylaxis of PCP. Aerosolized Pentamidine used for prophylaxis of PCP. 300mg Pentamide per dose/day for 4 weeks 300mg Pentamide per dose/day for 4 weeks Alternative Regimens Dapsone/Trimethoprim- Dapsone 100mg Daily. Clindamycin/Primaquine- 600mg IV infusion, 15mg oral for 14 days. Pyrimethamine/ Folinic Acid -25mg twice a day, 3mg vitamin/day IM.

Streptococcus Pneumonia and Haemophilus Influenza Treatment ß-Lactam antibiotics, the cornerstone of therapy 1.Ceftriaxone or cefotaxime -2 g/day for 7 – 10 days. 2.Amoxycillin with sublactum of clauvinic acid- 2-3g/day IM or IV. 3.Newer Quinolones - Cipro,Gatifloxacin,500mg IV BID. 4.Vancomycin used only as last resort- 600mg IV /per day, slow administration. * Pneumonia caused by a penicillin-sensitive strain - 24 million units of penicillin. ** Rifampicin is used for chemoprophylaxis and carrier status eradication.

What are the most likely organisms causing the patients diarrhea? Parasitic -Cryptosporidia, Microsporidia and Isospora belli Fungal - Histoplasmosis, Coccidioidomycosis, and Penicilliosis Bacterial -Salmonella and Campylobacter Viral – CMV

What are the therapeutic options for these agents ? Parasitic Diarrhea 1.Therapy is predominantly supportive. 2.Albendazole, 400 mg bid, has been reported to be of benefit. 3.TMP/SMX thrice-weekly regimen, similar to prophylaxis against PCP. Fungal Diarrhea 1.Fluconazole -200mg /day oral. 2. Lipid -Amphotrecin- B, IV in severe cases.

Bacterial Diarrhea 1.Quinolones are mainstay- Ciprofloxaxin 500mg tid. 2.Azithromycin 1 g single dose as alternative regime. *Bismuth subsalicylate is an inexpensive agent for the prophylaxis of diarrhea Viral Diarrhea 1.Ganciclovir –IV 5-10mg per kg, slow infusion. 2.Foscarnet- 60mg/kg IV for upto 21 days for maintainence.