Setting: Kaiser Permanente Northern California dialysis registry.
Objective: To examine the incidence of tuberculosis disease (TB) in a large, insured population of dialysis patients and to describe the disease characteristics and outcomes of these cases.
Design: Cohort study of all Kaiser patients who initiated dialysis between 1 January 1995 and 31 December 1999. TB incidence in our cohort between 1 January 1995 and 31 December 2000 was determined through electronic databases of out-patient diagnoses, laboratory results, and pharmacy records. The incidence of TB in the general population was determined from mandatory reporting of TB cases compiled by the California Department of Health Services.
Results: During the 6-year period of observation, 13 cases of TB occurred among 2806 dialysis initiators. The incidence of TB in the dialysis cohort was 134 per 100,000 person-years, compared to an incidence of 11.9/100,000 in the California population, yielding a relative risk of 11.3. Extra-pulmonary disease occurred in eight of 11 patients for whom site of disease was recorded. Five of 13 patients died within 3 months of TB diagnosis.
Conclusions: The dialysis population is at high risk of TB. Physicians caring for dialysis patients must remain vigilant for signs of TB in this vulnerable population.