Disseminated tuberculosis associated with fingolimod treatment in a patient with multiple sclerosis

Fingolimod is a sphingosine-1-phosphate receptor modulator approved as a disease-modifying therapy (DMT) for relapsing-remitting multiple sclerosis (MS). A woman in her 30s was treated with fingolimod for relapsing-remitting MS. After 7 years of treatment, she presented with non-productive cough, night sweats, breathlessness and unintentional weight loss. She had a negative interferon-gamma release assay (IGRA). A high-resolution CT thorax showed innumerable miliary opacities in both lungs. Bronchoalveolar lavage was positive for Mycobacterium tuberculosis complex PCR. An MRI head showed multiple small punctate contrast-enhancing lesions most typical for tuberculomas. We describe the first reported case of disseminated tuberculosis (TB) associated with fingolimod treatment. Patients who are receiving DMT must be closely observed for the development of opportunistic infections, and IGRA results should be interpreted with caution. Screening for latent TB prior to commencing fingolimod should be considered on an individual basis. The management of TB in MS patients on DMT requires an interdisciplinary approach.