Abstract:
The purpose of this study was to assess the association between human T-lymphotropic virus 1
(HTLV-1) and a lifetime history of active tuberculosis (TB) among relatives of HTLV-1-infected
patients. We reviewed clinical charts of all relatives of HTLV-1-infected index cases who attended
our institute in Lima from 1990–2004. The data of 1233 relatives was analysed; 394 (32.0%) were
HTLV-1 positive. Eighty-one subjects (6.6%) had a history of active TB, including 45/394
(11.4%) HTLV-1-positive and 36/839 (4.3%) HTLV-1-negative relatives (P<0.001). On
multivariate analysis, three factors were associated with TB history : HTLV-1 infection (adjusted
OR 2.5, 95% CI 1.6–3.9), age (adjusted OR 1.3, 95% CI 1.1–1.5 per 10-year age increase) and
relation to the index case (adjusted OR 2.6, 95% CI 1.3–5.1, for siblings vs. spouses of index
cases). In conclusion, HTLV-1 infection may increase the susceptibility to active TB. In
populations where both infections are frequent, such an association could affect the dynamics
of TB.