Latent tuberculosis diagnostic tests to predict longitudinal tuberculosis during dialysis: a meta-analysis.

SETTING

Tuberculosis (TB) rates in dialysis patients are more than 10 times greater than in the general population. Recent recommendations advise the use of interferon-gamma release assays (IGRAs) over the tuberculin skin test (TST) to aid in the diagnosis of latent tuberculous infection (LTBI); however, their longitudinal predictive ability for TB development has not been assessed.

OBJECTIVE

To determine whether the TST or IGRA are able to predict longitudinal TB development in dialysis patients.

DESIGN

We performed a systematic review to determine the longitudinal risk of TB in dialysis patients. Random-effects meta-analysis was used to determine the incidence rate ratio (IRR) of longitudinal TB development and the predictive value of such tests.

RESULTS

Eight studies were included. An IRR of 2.59 (95%CI 1.20-5.57) for longitudinal TB was seen in patients with a TST ⩾ 10 mm compared to patients with a TST < 10 mm. The positive predictive value (PPV) of a TST ⩾ 10 mm was 11.93% and the negative predictive value was 94.03%. We were unable to analyse the studies that used IGRAs, as only one study had TB events.

CONCLUSION

A TST with a 10 mm cut-off point appears to offer the capability to distinguish long-term risk of TB, with a modest PPV. The predictive value of IGRAs could not be quantified.