Conidiobolomycosis: apparent yet overlooked. A report of two cases

Conidiobolomycosis is a rare, chronic subcutaneous fungal infection caused primarily by Conidiobolus coronatus and Conidiobolus incongruus. It predominantly affects immunocompetent individuals and presents as slowly progressive rhino-facial swelling. Due to its indolent nature and rarity, it is often misdiagnosed, leading to delayed treatment and potentially disfiguring outcomes. We report two successfully treated cases of conidiobolomycosis from Sri Lanka.

The first patient, a 27-year-old immunocompetent male, presented with a six-month history of left-sided nasal obstruction, rhinorrhea, and gradual, painless swelling that initially affected the left nasal cavity and later extended to the left cheek, infraorbital region, and right nasal side. Histopathological examination of excision biopsy specimens revealed broad, aseptate fungal hyphae with associated necrotizing granulomatous inflammation and dense eosinophilic infiltrates. He was treated with oral itraconazole 200 mg twice daily and saturated potassium iodide solution (1 ml three times daily). Clinical symptoms completely resolved after six weeks, and therapy was continued for an additional month before cessation. The second patient, a 59-year-old previously healthy female, presented with a five-month history of progressive left-sided nasal congestion and disfiguring swelling over the nose. Clinical examination and radiological assessment revealed soft tissue thickening in the nasolabial fold extending into the nasal septum. Biopsy samples showed granulomatous inflammation with broad, sparsely septate fungal hyphae, confirmed on Grocott-Gomori methenamine silver (GMS) staining. Direct microscopy with 10% potassium hydroxide (KOH) demonstrated thin-walled, hyaline hyphae with irregular branching and few septations. She also recovered completely with itraconazole treatment. Both patients achieved complete resolution with medical management, emphasizing that early recognition and targeted antifungal therapy can lead to excellent outcomes in conidiobolomycosis.

Despite its rarity, this infection should be considered in patients presenting with persistent rhino-facial swelling, especially in endemic areas. While the prognosis is generally good, prolonged therapy may be necessary, and cosmetic deformities may persist. Increased clinical awareness and timely diagnosis are essential to prevent complications and disfigurement associated with this overlooked fungal infection.