CHRONIC ERYTHEMA NODOSUM AS A SIGN OF TUBERCULOSIS INFECTION

Abstract

Abstract Introduction: Erythema nodosum (EN) is a subcutaneous fat tissue inflammation (panicullitis) characterized by diffuse erythematous nodules symmetrically distributed in the anterior part of the lower extremities. EN is considered as a reactive process which can be triggered by a wide variety of factors including mycobacterium (M.) tuberculosis infection. Case: A 21-year-old woman, presented in our department with a 9-month-history of painful erythematous nodules on both legs accompanied by ankle swelling and joint pain. Previous treatments with amoxicillin-clavulanic acid, steroid, and nonsteroidal anti-inflammatory drug (NSAID) did not yield satisfactory results. On examination, we found multiple tender erythematous nodules symmetrically distributed on both legs. On laboratory examination, C-reactive protein and erythrocyte sedimentation rate were increased, interferon-gamma release assay (IGRA) test was found positive for M. tuberculosis infection. The patient was treated with standard anti-tuberculosis regimen and hexagonal water without additional steroids or other immunosupressive drugs. Clinical resolution was gradually achieved and by the third month of therapy only minimal post-inflammatory hyperpigmentation lesions remained. Discussion: EN is a self-limiting disease but in certain cases can be chronic and refractory. Identification and elimination of underlying causes of EN are essential to achieve satisfying results. Conclusion: We reported a case of EN with positive IGRA result for M. tuberculosis infection which was successfully treated with anti-tuberculosis regimen. Keywords: erythema nodosum, mycobacterium tuberculosis, interferon gamma release assay, anti-tuberculosis drugs