A rare case of subcutaneous zygomycosis on the neck of an immunocompetent patient

Abstract

Zygomycosis is a sporadic entity affecting subcutaneous tissue characterized by painless gradually growing nodules that often appear on the trunk, extremities, and occasionally in other regions. It is included among the diseases that cause the chronic granulomatous reaction of the tissues. It predominantly affects immunocompromised patients by invading the brain, lungs, and gastrointestinal tract, but it has also been reported in immunocompetent patients with manifestations primarily in the cutaneous and subcutaneous tissues. The relatively low incidence of this disease limits clinical suspicion, often leading to a delay in diagnosis. Here we present the case of an immunocompetent 18-year-old Venezuelan male, with a rapidly growing neck mass that was earlier misdiagnosed as Tuberculosis. The diagnosis was made by tissue biopsy that revealed the presence of thin-walled hyphae, often chambered or fragmented, surrounded by an eosinophilic sheath (Splendore-Hoeppli phenomenon) which is a significant feature of this mycosis. Once diagnosed, the patient responded well to medical management with potassium iodide. Zygomycosis causes a wide spectrum of pathologies in immunocompromised patients. However, there should be a high clinical suspicion to establish its diagnosis, which is particularly important in atypical immunocompetent patients.