Table 1. Comparisons of baseline clinical and laboratory variables between influenza patients with positive and negative fecal viral RNA detection test results, Hong Kong, 2006–2009*.
| Patient characteristics | Fecal viral RNA–positive, n = 56 | Fecal viral RNA–negative, n = 63 | p value |
|---|---|---|---|
| Mean age, y (SD) | 65.3 (18.6) | 69.9 (13.4) | 0.12 |
| Age group, y, no. (%) | 0.35† | ||
| 18–49 | 7 (13) | 6 (10) | |
| 50–65 | 18 (32) | 14 (22) | |
| >65 | 31 (55) | 43 (68) | |
| Female sex, no. (%) | 33 (59) | 30 (48) | 0.27 |
| Interval from illness onset to sample collection <5 d, no. (%) | 52 (93) | 53 (84) | 0.14 |
| Concurrent condition, no. (%) | |||
| Any | 36 (64) | 43 (68) | 0.65 |
| Major‡ | 31 (55) | 37 (59) | 0.72 |
| Virus isolation, nasopharyngeal aspirates | 50 (89) | 49 (77) | 0.06 |
| Signs and symptoms when care was sought, no. (%) | |||
| Fever | 48 (86) | 53 (84) | 1.00 |
| Cough and sputum | 39 (74) | 45 (76) | 0.83 |
| Sore throat | 15 (28) | 18 (31) | 0.84 |
| Rhinorrhea | 21 (40) | 21 (36) | 0.70 |
| Shortness of breath | 18 (34) | 27 (46) | 0.25 |
| Vomiting or diarrhea | 10 (18) | 9 (14) | 0.63 |
| Vomiting | 7 (13) | 8 (13) | 1.00 |
| Diarrhea | 5 (9) | 2 (3) | 0.25 |
| Laboratory parameters when care was sought | |||
| Total leukocyte count, × 109 cells/L, median (IQR) | 7.3 (5.9–8.9) | 7.9 (6.1–10.3) | 0.18 |
| Neutrophil count, × 109 cells/L, median (IQR) | 5.1 (4.2–7.0) | 6.0 (4.1–7.7) | 0.22 |
| Lymphocyte count, × 109 cells/L, median (IQR) | 0.8 (0.6–1.1) | 0.9 (0.6–1.2) | 0.20 |
| Lymphocyte count <1.0 × 109 cells/L, no. (%) | 37 (66) | 29 (46) | 0.03 |
| Monocyte count, × 109 cells/L, median (IQR) | 0.7 (0.5–0.9) | 0.7 (0.5–0.9) | 0.51 |
| Platelet count, × 109 cells/L, median (IQR) | 180 (142–228) | 196 (156–248) | 0.20 |
| Alanine aminotransferase level, IU/L, median (IQR) | 19 (13–32) | 22 (15–36) | 0.54 |
| Antiviral treatment, no. (%) | |||
| Oseltamivir§ | 35 (63) | 42 (67) | 0.70 |
| Zanamivir | 6 (11) | 5 (8) | 0.75 |
| Specimen collected after starting antiviral drugs, no. (%) | 39 (70) | 42 (67) | 0.84 |
| Complication, no. (%) | |||
| Any | 39 (70) | 44 (70) | 0.98 |
| Cardiorespiratory¶ | 29 (52) | 38 (60) | 0.36 |
| Clinical outcome, no. (%) | |||
| ICU admission | 2 (4) | 0 (0) | 0.22 |
| Death | 0 | 0 | NA |
| Median duration of hospitalization, d (IQR) | 6 (4–12) | 5 (4–13) | 0.50 |
*Univariate comparisons of categorical and continuous variables were performed by using Fisher exact test and Mann-Whitney U test or Student t test, whenever appropriate. IQR, interquartile range; ICU, intensive care unit; NA, not applicable. †Fisher 2×3 exact test. ‡Defined as congestive heart failure; cerebrovascular, neoplastic, chronic liver, and renal diseases; diabetes; ischemic heart disease; or use of immunosuppressant drugs (8). Approximately 5% of patients were profoundly immunocompromised. §Oseltamivir (standard oral regimen, 75 mg 2×/d for 5 d). Amantadine was coadministered to 7 patients during the 2008–09 influenza season. ¶Defined as pneumonia, acute bronchitis, acute exacerbation of chronic respiratory conditions (e.g., chronic obstructive pulmonary disease, asthma); acute coronary syndrome, decompensated heart failure, arrhythmia, or acute cerebrovascular events (8).