Analyses of fluoroquinolones and Clostridium difficile-associated diarrhoea in tuberculosis patients

Systematic studies of fluoroquinolones (FQs) and Clostridium difficile-associated diarrhoea (CDAD) are scarce among tuberculosis (TB) patients, in whom fluoroquinolones (FQs) are increasingly used.

To evaluate the relationship between FQs and CDAD among TB patients.

Retrospective cohort and nested case-control analyses were conducted among 3319 hospital patients on anti-tuberculosis treatment from 1999 to 2005. Each case of CDAD was matched by three sex- and age-matched controls randomly selected from the rest of the cohort. Not every case was confirmed by C. difficile cytotoxins.

Among 38 cases studied, the incidence of CDAD, which was 28.2 (95%CI 20.3-38.3) per 100 000 patient-days overall, increased from 12.9 (95%CI 5.8-25.3) for patients aged <60 years to 26.6 (95%CI 15.5-42.8) for those aged between 60 and 79 years, and 66.9 (95%CI 39.8-106.1) for those aged >79 years. Univariate analysis showed a significant association between CDAD and age, FQs, non-FQ antibiotics, serum albumin level, duration of hospital stay and nasogastric feeding. Only duration of hospital stay and nasogastric feeding remained significant on multivariable analysis.

The risk of CDAD due to FQs among TB patients is probably modest after controlling for sex, age, non-FQ antibiotics, serum albumin level, duration of hospital stay and nasogastric feeding.