Detecting latent tuberculosis infection in hemodialysis patients: a head-to-head comparison of the T-SPOT.TB test, tuberculin skin test, and an expert physician panel.
Current guidelines advocate screening hemodialysis patients for latent tuberculosis infection; however, the tuberculin skin test (TST) is believed to be insensitive in this population. This study compared the diagnostic utility of the TST with that of an IFN-gamma assay (T-SPOT.TB) and the clinical consensus of an expert physician panel. A total of 203 patients with ESRD were evaluated for latent tuberculosis infection with the TST, T-SPOT.TB test, and an expert physician panel. Test results were compared with respect to their association with established tuberculosis risk factors. Tuberculosis infection, as estimated by the tuberculin test, T-SPOT.TB test, and expert physician panel, was detected in 12.8%, 35.5, and 26.1 of patients respectively. Among patients with a history of active tuberculosis and radiographic markers of previous infection, 78.6 and 72.7% had positive T.SPOT.TB results, compared with 21.4 and 18.2% who had positive tuberculin tests. The physician panel unanimously declared infection in these two groups. On multivariate analysis, a positive T-SPOT.TB test was associated with a history of active tuberculosis, radiographic markers of previous infection, and birth in an endemic country, whereas a physician panel diagnosis also was associated with a history of previous tuberculosis contact. The TST is insensitive in hemodialysis patients and is not recommended to be used in isolation to diagnose latent tuberculosis infection. It is suggested that a combination of T-SPOT.TB testing and medical assessment may be the most accurate screening method.
Passalent
Laura
L
Infection Prevention and Control Unit, St. Michael's Hospital, Toronto, Ontario, Canada.
Khan
Kamran
K
Richardson
Robert
R
Wang
Jun
J
Dedier
Helen
H
Gardam
Michael
M
D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards; D006801:Humans; D007676:Kidney Failure, Chronic / Q000453:epidemiology* / Q000628:therapy; D016015:Logistic Models; D008403:Mass Screening / Q000379:methods / Q000592:standards; D008511:Medicine; D015999:Multivariate Analysis; D011446:Prospective Studies; D011859:Radiography; D006435:Renal Dialysis; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013038:Specialization; D014374:Tuberculin Test / Q000592:standards; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000453:epidemiology*