An unusual case of cutaneous tuberculosis and paradoxical TB in a patient with spondyloarthritis treated with adalimumab.

Cutaneous tuberculosis (TB) is an uncommon condition, the diagnosis of which can be challenging. Biologic disease-modifying anti-rheumatic drugs (bDMARDs) are associated with a higher risk of opportunistic infections, including TB. We present a case of cutaneous TB in a 56-year-old male with psoriatic arthritis on adalimumab. He developed skin lesions on his thumb and axilla, and Mycobacterium tuberculosis was isolated in cultures sent from a skin biopsy. Four months after commencement of TB treatment, he presented with a new onset of seizures. An MRI head showed two tuberculomas, with no further lesions identified in cross-sectional imaging. A tapering course of steroids was started alongside a 12-month course of anti-TB treatment for post-tuberculous treatment paradoxical reaction. In conclusion, although uncommon, cutaneous TB should be considered in patients on bDMARD treatment with atypical skin lesions.