Table 1.
Clinical Characteristics at Hospital Presentation
| Variable | CT-Only Pneumonia (n = 66) | Pneumonia on Chest Radiography (n = 2,185) | P Value |
|---|---|---|---|
| Demographics | |||
| Age, median (IQR), y | 53 (40-63) | 58 (47-71) | < .01 |
| Female sex, No. (%) | 39 (59.1) | 1,111 (50.9) | .18 |
| Vital signs, median (IQR) | |||
| Heart rate, beats/min | 100 (88-118) | 100 (87-114) | .51 |
| Systolic blood pressure, mm Hg | 140 (126-157) | 131 (114-148) | < .01 |
| Respiratory rate, breaths/min | 20 (18-24) | 20 (18-24) | .62 |
| Temperature, °C | 36.9 (36.3-37.9) | 36.9 (36.2-37.8) | .73 |
| Oxygen saturation, % | 96 (94-98) | 95 (92-97) | .07 |
| Signs and symptoms, No. (%) | |||
| Cough with sputum production | 39 (59.1) | 1,206 (55.2) | .53 |
| Hemoptysis | 5 (7.6) | 192 (8.8) | .73 |
| Shortness of breath | 49 (74.2) | 1,703 (77.9) | .48 |
| Chest pain | 44 (66.7) | 1,065 (48.7) | < .01 |
| Confusion | 11 (16.7) | 438 (20.1) | .50 |
| Wheezing | 37 (56.1) | 937 (42.9) | .03 |
| Comorbidities, No. (%) | |||
| Asthma | 21 (31.8) | 561 (25.7) | .26 |
| COPD | 14 (21.2) | 505 (23.1) | .72 |
| Chronic heart failure | 8 (12.1) | 422 (19.3) | .14 |
| Diabetes mellitus | 21 (31.9) | 563 (25.8) | .27 |
| Chronic kidney disease | 9 (13.6) | 344 (15.7) | .64 |
| Chronic liver disease | 3 (4.6) | 122 (5.6) | .72 |
| Obesity (BMI ≥ 30 kg/m2) | 32 (48.5) | 789 (36.1) | .04 |
| Current tobacco smoker | 17 (25.8) | 577 (26.4) | .91 |
| Laboratory values, median (IQR) | |||
| WBC count, cells/μL | 11,050 (6,900-14,200) | 11,400 (8,000-14,900) | .13 |
| Blood urea nitrogen, mg/dL | 12 (9-19) | 15 (10-24) | < .01 |
| Blood glucose, mg/dL | 120 (102-144) | 115 (99-145) | .46 |
| Procalcitonin, ng/mLa | < 0.05 (<0.05-0.11) | 0.16 (< 0.05-0.85) | < .01 |
| Pneumonia severity | |||
| Index risk class, No. (%) | |||
| I-II (low risk) | 41 (62.1) | 979 (44.8) | .02 |
| III (moderate risk) | 11 (16.7) | 439 (20.1) | |
| IV-V (high risk) | 14 (21.2) | 767 (35.1) | |
| CURB-65 score, No. (%) | |||
| 0-1 (low risk) | 53 (80.3) | 1,517 (69.4) | .14 |
| 2 (moderate risk) | 7 (10.6) | 422 (19.3) | |
| 3-5 (high risk) | 6 (9.1) | 246 (11.3) | |
| ATS severe pneumonia criteria, No. (%) | |||
| < 3 criteria (not severe) | 63 (95.5) | 2,028 (92.8) | .62 |
| ≥ 3 criteria (severe) | 3 (4.5) | 157 (7.2) |
ATS = American Thoracic Society; CURB-65 = confusion, uremia, respiratory rate, blood pressure, age ≥ 65 years; IQR = interquartile range.
a
Five hundred twenty patients did not have PCT measured, including 17 (25.8%) in the CT-only pneumonia group and 503 (23.0%) in the pneumonia seen on chest radiography group.