Volume 19, Number 9—September 2013
Letter
Clostridium difficile Infection Caused by Binary Toxin–Positive Strains
Table
Thirty-day mortality rates, stratified by binary toxin status, for persons with Clostridium difficile infection, the Netherlands, 2006–2009*
| Binary toxin status of infecting strain | Absolute 30-day mortality |
Relative 30-day mortality, HR (95% CI)† |
|||||
|---|---|---|---|---|---|---|---|
| No adjustment | Adjusted for age | Adjusted for age and concurrent condition |
|||||
| No. | % (95% CI) | Method 1 | Method 2 | Method 3 | |||
| Positive | |||||||
| 027, N = 55 | 12 | 22 (13–35) | 2.2 (1.2–4.2) | 2.0 (1.1–3.8) | 2.4 (1.1–5.5) | 2.0 (0.8–5.4) | 2.0 (0.7–5.5) |
| Non-027, N = 100 | 15 | 15 (9–23) | 1.5 (0.8–2.6) | 1.4 (0.8–2.5) | 1.3 (0.6–2.7) | 1.1 (0.5–2.8) | 1.1 (0.4–2.9) |
| Negative, N = 471‡ | 50 | 11 (8–14) | 1.0 (ref) | 1.0 (ref) | 1.0 (ref) | 1.0 (ref) | 1.0 (ref) |
| Unknown, N = 724§ | 100 | 14 (11–17) | 1.3 (0.9–1.9) | 1.3 (0.9–1.9) | 1.4 (0.9–2.2) | 1.5 (0.9–2.3) | 1.3 (0.7–2.4) |
*HR, hazard ratio; ref, reference.
†In the model, age and Charlson index were added as continuous variables; all others were dichotomous. Method 1, adjusted for age and history of admissions and antimicrobial drug use in the prior 3 mos. Method 2, adjusted for age; diseases of the respiratory, digestive, circulatory, and genitourinary systems; endocrine diseases; neoplasms and other diseases; history of admissions and antimicrobial drug use in the prior 3 mos. Method 3, adjusted for age; history of admissions; antimicrobial drug use in the prior 3 mos.; and Charlson comorbidity index.
‡Binary toxin–positive non-027 strains belonged to 8 PCR ribotypes (76% type 078).
§Binary toxin–negative strains belonged to 64 different PCR ribotypes (23% type 014).