Background and objective

Studies have reported an increased tuberculosis (TB) incidence among patients with end-stage renal disease (ESRD). This nationwide nested Case–control study investigated the risk of active TB due to nosocomial exposure and its correlation with the delay in TB treatment in hemodialysis patients.

Methods

Adult (aged ≥20 years) patients with incident ESRD over 2000–2010 were identified from Taiwan National Health Insurance Research Database; 2331 patients with incident active TB (Case) were matched with 11,655 patients without TB (control) by age, sex, year of ESRD onset, Charlson comorbidity index, chronic obstructive pulmonary disease, and diabetes mellitus, at a 1:5 case-to-control ratio.

Results

Compared with the control group, the Case group had greater nosocomial exposure to index patients with pulmonary TB (2.36 vs. 0.11 month of exposure, p < 0.001). Nosocomial exposure increased active TB risk (adjusted odds ratio [OR; 95% confidence interval, CI]: 1.60 [1.55–1.66] per month of exposure), particularly when the exposure time was either within 6 months before the index case was diagnosed or 6–15 months before the ESRD patient became an incident active TB case. For patients with active TB, cough-related medication prescriptions (proxy for cough symptoms) exponentially increased over 6 months before TB treatment.

Conclusion

Nosocomial exposure attributed to delay in the diagnosis of index pulmonary TB is important in TB transmission among patients undergoing regular hemodialysis. Additional studies investigating how TB can be diagnosed and treated early are warranted.

Summary at a glance

Our study revealed that nosocomial exposure, attributed to delay in pulmonary TB diagnosis, is important in TB transmission among patients undergoing regular hemodialysis. Strategies to diagnose and treat TB early are crucial to infection control, and they warrant further investigations.