Disseminated pheohyphomycosis
Authors: Shivaswamy Kanakapura N. , Pradhan Prashanth , Laxmisha Chandrashekar , Thappa Devinder M. , Jayanthi Soundararaghavan 
Published: August 2006

A 40‐year‐old male agricultural laborer presented to our clinic with asymptomatic swellings on his left hand and left leg of 2 years’ duration. A pea‐sized swelling was first noticed on the back of the left hand, which was gradual in onset and slowly progressed to its present size. The patient later noticed multiple swellings over his left leg and thigh, with a similar progression. There was no history suggestive of inflammatory changes or discharge from the lesions. There was no previous history of trauma. The patient was an asthmatic and was on long‐term oral steroid therapy (10–20 mg/day prednisolone). None of his family members had similar complaints.

On physical examination, the patient was febrile. Cutaneous examination showed multiple, circumscribed, lobulated, nontender, mobile, cystic swellings of various sizes, ranging from less than 2 cm over the left shin to more than 8 cm over the dorsum of the left hand and ankle (Fig. 1a,b). The surface over these swellings was shiny, smooth, and intact. The skin over the swellings was pliable and normal in color. There was no regional lymphadenopathy. The rest of the clinical examination was normal, except for decreased breath sounds over the left mid and lower pulmonary lobes.

Lobulated cystic subcutaneous swellings over the dorsum of the left hand (a) and lower leg (b)

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Routine laboratory tests, including complete blood count and liver and renal function tests, were within normal limits. Random blood glucose was greater than 400 mg%. Histopathologic examination of one of the cysts (from the hand) showed pheohyphomycotic cysts lined by dense fibrous tissue with chronic inflammatory infiltrate admixed with scattered giant cells in the dermis (Fig. 2). No fungal elements were visualized in the hematoxylin and eosin‐stained sections. The fungal elements were found within the cystic cavity on special staining with Gomori's methenamine silver (GMS) and Masson–Fontana stains. The hyphae had irregularly placed branches and showed constrictions around their septae, thus resembling pseudohyphae and yeast forms (Fig. 3). Fine needle aspiration cytology from one of the swellings showed the presence of filamentous fungi on KOH examination and brown‐pigmented distorted filaments and yeast‐like cells on Masson–Fontana staining (Fig. 4a,b). The positive Masson–Fontana stain was indicative of the presence of melanin in the fungal hyphae, even when the fungal hyphae were not pigmented in the hematoxylin and eosin‐stained section. Periodic acid–Schiff reagent also stained the fungal elements, thus confirming our diagnosis of pheohyphomycosis and ruling out the possibility of hyalohyphomycosis. The culture for fungus from the swelling aspirate grew contaminants. The chest X‐ray showed dense nodular shadows in the left lower and mid pulmonary lobes. Sputum for acid‐fast bacilli and Mantoux test were negative. During the hospital stay, the patient developed high fever and showed altered behavior, for which a computed tomography scan of the brain was performed; this showed evidence of multiple ring enhancing lesions in both frontal lobes. Ultrasound of the abdomen was normal. On the basis of the above findings, a diagnosis of disseminated subcutaneous pheohyphomycosis was made.

Photomicrograph showing subcutaneous cyst lined by fibrous tissue and containing granulomatous inflammatory infiltrate (hematoxylin and eosin, ×100)

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Photomicrograph demonstrating filamentous fungi resembling pseudohyphae and yeasts inside the pheohyphomycotic cyst (Gomori's methenamine silver stain, ×400)

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Photomicrographs of fine needle aspirate from the pheohyphomycotic cyst demonstrating filamentous fungi resembling pseudohyphae and yeasts: (a) Masson–Fontana stain, ×400; (b) periodic acid–Schiff stain, ×400

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The patient was given itraconazole, 100 mg twice daily, and his diabetes was managed with insulin. The fever stopped within a week and the altered behavior also started to show an improvement. There was obvious improvement in neurologic signs and symptoms. His skin lesions, however, responded slowly to the treatment. The patient did not report for further follow‐up after 1 month.