Table 1.
Patient characteristics
| Variables | All CAP | Staphylococcus aureus | Pneumococcus |
| (n = 1413) | (n = 196) | (n = 198) | |
| Age ≥80 years | 572 (40.5) | 91 (46.4) | 62 (31.3) |
| Sex, male | 915 (64.8) | 124 (63.3) | 122 (61.6) |
| Comorbidities | |||
| Neoplastic diseases | 208 (14.7) | 27 (13.8) | 24 (12.1) |
| Chronic lung diseases | 470 (33.3) | 71 (36.2) | 53 (26.8) |
| Congestive heart failure | 183 (13.0) | 32 (16.3) | 15 (7.6) |
| Chronic renal diseases | 113 (8.0) | 14 (7.1) | 15 (7.6) |
| Chronic liver diseases | 53 (3.8) | 6 (3.1) | 8 (4.0) |
| Central nervous system disorders | 304 (21.5) | 64 (32.7) | 25 (12.6) |
| Diabetes | 258 (18.3) | 31 (15.8) | 35 (17.7) |
| Immunosuppression | 129 (9.1) | 14 (7.1) | 22 (11.1) |
| Non-ambulatory status | 338 (23.9) | 82 (41.8) | 35 (17.7) |
| Physical findings | |||
| Glasgow Coma Scale ≤12 | 249 (17.6) | 61 (31.1) | 21 (10.6) |
| Pulse rate ≥125 beats per min | 140 (9.9) | 24 (12.2) | 20 (10.1) |
| Systolic blood pressure <90 mm Hg | 81 (5.5) | 22 (11.2) | 14 (7.1) |
| Respiration rate ≥30 breaths per min | 314 (22.2) | 48 (24.5) | 43 (21.7) |
| Laboratory findings | |||
| Hematocrit <0.3 | 213 (15.1) | 33 (16.8) | 24 (12.1) |
| Platelet count <120,000/mm3 | 115 (8.1) | 18 (9.2) | 14 (7.1) |
| Albumin <3.0 g/dL | 478 (33.8) | 96 (49.0) | 57 (28.8) |
| Glucose ≤60 or ≥300 mg/dL | 69 (4.9) | 14 (7.1) | 11 (5.6) |
| Blood urea nitrogen ≥30 mg/dL | 310 (21.9) | 56 (28.6) | 44 (22.2) |
| Na <130 or ≥150 mEq/L | 118 (8.4) | 28 (14.3) | 14 (7.1) |
| Creatinine ≥1.2 | 290 (20.5) | 36 (18.4) | 43 (21.7) |
| pH <7.35 | 149 (10.5) | 27 (13.8) | 14 (7.1) |
| PaO2/FiO2 ≤250 | 531 (37.6) | 104 (53.1) | 63 (31.8) |
| Radiographic findings | |||
| Bilateral lung involvement | 649 (45.9) | 110 (56.1) | 84 (42.4) |
| Pleural effusion | 344 (24.3) | 53 (27.0) | 37 (18.7) |
| Pneumonia Severity Index class | |||
| I–III | 441 (31.2) | 35 (17.9) | 81 (40.9) |
| IV | 534 (37.8) | 86 (43.9) | 74 (37.4) |
| V | 372 (26.3) | 67 (34.2) | 37 (18.7) |
CAP: community-acquired pneumonia
PaO2/FiO2: ratio of arterial oxygen partial pressure to fractional inspired oxygen
Data are present as number and percentage.
Immunosuppression included any immunosuppressive diseases such as congenital and acquired immunodeficiency, hematological diseases, and neutropenia (<1000/mm3); treatment with immunosuppressive drugs within the previous 30 days; and corticosteroids dosages of at least 10 mg/day of a prednisone equivalent for more than 2 weeks.
Non-ambulatory status was defined as being bedridden or using a wheelchair because of difficulty walking.