| Characteristic | No (%)* |
| City | |
| New Orleans | 111 (65) |
| San Francisco | 61 (35) |
| Age (y) | |
| <35 | 27 (16) |
| 35–44 | 75 (45) |
| 45–54 | 57 (34) |
| ⩾55 | 8 (5) |
| Sex | |
| Female | 48 (28) |
| Male | 123 (72) |
| Ethnicity | |
| African–American | 123 (72) |
| Caucasian | 33 (19) |
| Other | 16 (9) |
| CD4+ T cell count (cells/μl) | |
| > 200 | 36 (25) |
| 101–200 | 32 (22) |
| 51–100 | 23 (16) |
| ⩽50 | 55 (38) |
| HIV RNA (copies/ml) | |
| <75 | 9 (8) |
| ⩾75–<20 000 | 20 (17) |
| ⩾20 000–<100 000 | 32 (28) |
| ⩾100 000 | 54 (47) |
| Prior PCP | 53 (31) |
| PCP prophylaxis on admit | |
| Co-trimoxazole | 51 (30) |
| Other | 20 (12) |
| Aetiology of pneumonia | |
| Bacterial | 104 (60) |
| Opportunistic† | 22 (13) |
| Non-infectious‡ | 18 (10) |
| Undiagnosed | 28 (16) |
*Up to 57 observations may be missing (as for HIV RNA), but percentages are calculated as a proportion of actual observations. Percentages may not total 100% due to rounding. †Includes fungal, mycobacterial and viral pneumonias. ‡Includes Kaposi’s sarcoma, lymphoma and other non-infectious pulmonary processes, such as chronic obstructive pulmonary disease exacerbations and pulmonary oedema. PCP, Pneumocystis pneumonia.