Simultaneous Systemic Lupus Erythematosus Flare and Disseminated Tuberculosis: Balancing Anti-Mycobacterial and Autoimmune Treatments.

Here, we report the case of a 53-year-old man with suspected autoimmune arthritis on low-dose corticosteroid therapy. He was recently hospitalized due to presumed bacterial pneumonia and a seizure episode attributed to high fever. His condition deteriorated after discharge, and he presented to our institution with a persistent cough, weight loss, skin rash, arthralgias, fever, and altered mental status. The investigation led to the simultaneous diagnosis of a systemic lupus erythematosus (SLE) flare and disseminated tuberculosis (TB), both pulmonary and intracranial. Proteinuria and peripheral edema were identified, suggesting renal involvement of SLE. Anti-mycobacterial drugs and high-dose corticosteroid therapy were initiated. Given the risk of starting other immunosuppressive drugs in the presence of intracranial TB, in a patient with stable renal function and a significant decrease in proteinuria with corticosteroids and supportive therapy alone, renal biopsy was postponed. Prednisolone was progressively tapered down during the next six months, always maintaining anti-mycobacterial therapy, which resulted in a second SLE flare and the need to increase corticosteroids again. At this time, a renal biopsy was performed, showing class II lupus nephritis and confirming the diagnosis of SLE. After one year of anti-mycobacterial therapy with complete resolution of cerebral and pulmonary TB lesions, we chose to initiate mycophenolate mofetil as an immunosuppressive steroid-sparing agent with increased SLE control, allowing for corticosteroid reduction.