Melkersson–Rosenthal syndrome masquerading as mucocutaneous leishmaniasis in a high leishmaniasis-burden area: A case report

Melkersson–Rosenthal syndrome (MRS) is a rare neuro-mucocutaneous disorder characterized by the classical triad of recurrent orofacial swelling, peripheral facial palsy, and fissured tongue, although the complete presentation is uncommon. In regions where infectious diseases with overlapping manifestations are endemic, such as mucocutaneous leishmaniasis (MCL), MRS may be easily misdiagnosed. We present the case of a 30-year-old Ethiopian man with a 16-year history of recurrent, painless lip swelling initially treated as MCL without clinical improvement. Examination revealed firm swelling of the upper and right lower lips, a geographic tongue, and right-sided peripheral facial palsy. A prior lip biopsy had been interpreted as pemphigus vulgaris, further contributing to diagnostic delay. The presence of the complete clinical triad ultimately led to a diagnosis of MRS. The patient was managed with systemic corticosteroids, doxycycline, and intralesional triamcinolone acetonide, achieving significant improvement after three months and sustained response at six months. This case underscores the diagnostic challenges of MRS in leishmaniasis-endemic regions and highlights the importance of recognizing the classical triad to avoid misdiagnosis and facilitate timely, effective treatment. • Melkersson–Rosenthal syndrome (MRS) is a rare neuro-mucocutaneous disorder with a diagnostic triad. • In leishmaniasis-endemic regions, MRS may be misdiagnosed as mucocutaneous leishmaniasis. • This case of a young Ethiopian man demonstrates the complete triad with diagnostic delays. • Corticosteroids, doxycycline, and intralesional therapy achieved marked and sustained improvement.