Biologic therapy is associated with an increased risk for opportunistic infections, particularly the reactivation of latent tuberculosis infection (LTBI). The purpose of this study was to investigate the clinical characteristics and mortality rate of active Mycobacterium tuberculosis (TB) in patients with psoriasis taking biological treatments.

A systematic review of the databases PubMed, Google Scholar, ScienceDirect, Cochrane Library, and was conducted. From commencement to May 31, 2018, studies describing active TB in psoriasis patients following biologic treatment were considered. Clinical information, as well as death rates, were gathered.

Fifty-one papers involving 78 patients with active tuberculosis were included: 11 prospective studies, 13 retrospective studies, and 27 case reports/series. The majority of patients with active tuberculosis were men, and 85% were of European or Asian ethnicity. For 63% of patients, the pre-treatment LTBI test was negative. The disease manifested itself in 33% of patients within the first 3 months of therapy, and in 51% within the first 6 months. The majority of patients had extra-pulmonary tuberculosis, and 49% had disseminated illness. The overall mortality rate was 7%. Despite LTBI screening, some people develop active TB. Clinicians starting biological treatment in patients with psoriasis should be mindful of the clinical signs of active TB in this setting.