Development of leprosy in a patient with ankylosing spondylitis during the infliximab treatment: reactivation of a latent infection?

The use of tumor necrosis factor alpha as a treatment for chronic inflammatory conditions has been shown to be associated with an increased risk of developing infections, especially Mycobacterium tuberculosis, atypical mycobacteria, and other microorganisms. We report the case of a 58-year-old man with ankylosing spondylitis, receiving infliximab treatment, who presented with multiple plaques on the face, chest, and extremities, a thickened, tender ulnar nerve, and severe neuritis of the feet. The results of a biopsy of these lesions revealed histopathological features of lepromatous Hansen disease. The use of anti-tumor necrosis factor biologic agent on this patient may have resulted in either a new infection or reactivation of a latent infection of Mycobacterium leprae.