Lymphopenia and tuberculous lymphadenitis under immunomodulatory agents in a multiple sclerosis patient: Follow-up of a challenging case.

Interferon-beta (IFN-β) 1a and glatiramer acetate (GA) are first-line therapies for multiple sclerosis (MS) with immunomodulatory effects. We present a patient who developed lymphopenia and tuberculous lymphadenitis under treatment with these agents. The female patient who at present 65 year old is followed at our MS outpatient clinics had received GA (20 mg/day, subcutaneous injection) and later IFN-β 1a (44 µg, thrice weekly, subcutaneous injection). During the course of her treatment, she developed mild to severe lymphopenia. A follow up thoracic spinal MRI (when lymphocyte count was 800/µl) showed multiple enlarged lymph nodes in the posterior mediastinum incidentally. Further investigation revealed tuberculous lymphadenitis. She received anti-tuberculosis (TB) treatment for nine months and her condition resolved. Although immunomodulatory treatments are considered safe with regard to opportunistic infections, and lymphopenia under these treatments are generally accepted as mild and asymptomatic, our experience was different with this patient. Further studies on the management of patients with lymphopenia and assessment of the risk of TB under immunomodulatory agents are needed.