Disseminated cutaneous sporotrichosis: a marker of osteoarticular sporotrichosis masquerading as gout

A 60‐year‐old African man presented with an 8‐week history of skin lesions on the face and abdomen that began as small nodules in the malar area. In addition there was a year‐long history of swellings of the right wrist and knee joints and the dorsum of the left hand ( Fig. 1a–d). Two years earlier, he had had total replacement of the left knee joint because of histology‐proven chronic gouty arthritis ( Fig. 2a). The joint prosthesis was symptom‐free after surgery. He had sought medical advice for his symptoms, and based on the previous diagnosis of gouty arthritis and hyperuricemia, the joint problems were attributed to underlying gout. He was treated with allopurinol and nonsteroidal anti‐inflammatory drugs, but the arthralgia and swelling did not resolve. The patient, a keen gardener, admitted to heavy daily alcohol consumption. 1(a) Crusted, hypopigmented atrophic lesion with secondary hypopigmentation in the malar area and chin. (b) Indurated erythematous and subcutaneous nodules on trunk (arrows). (c) Cystic lesions on dorsum of hand (arrowheads). (d) Swelling of right knee joint (arrowheads)2(a) Biopsy of left knee demonstrating amorphous, fibrillar material with crystals and foreign body granulomatous reaction (H&E 240×). (b) Granulomatous inflammation and microabscess with Splendore‐Hoeppli phenomenon around fungal yeast (arrow) (H&E 480×) On examination crusted, hypopigmented, atrophic lesions with surrounding hyperpigmentation were present on the face ( Fig. 1a) and indurated, erythematous, subcutaneous nodules were identified on the trunk and limbs ( Fig. 1b). Roentgenograms revealed lytic lesions in the right femur and fibula, erosion of the right ulnar styloid and an intact prosthesis in the left knee joint. A provisional diagnosis of lupus vulgaris or a deep mycoses with incidental joint pathology such as gout or rheumatoid arthritis was made. The Mantoux skin test, Wasserman reaction, rheumatoid factor, antinuclear factor, and HIV investigations were negative. The serum uric acid level was 0.8 mmol/L (normal: 0.15–0.45) and erythrocyte sedimentation rate was 30 mm/h. Skin biopsies of the face and trunk revealed granulomatous inflammation with microabscess formation and the presence of focal fungal yeast forms surrounded by a Splendore‐Hoeppli phenomenon, confirming cutaneous sporotrichosis ( Fig. 2b). Culture of lesional skin on blood agar grew budding yeasts of Sporothrix schenckii at 37 °C. The mold phase was isolated at room temperature (25 °C) on Saboraud's dextrose agar. Subsequently, the cysts on the dorsum of the hand and the left knee joint were biopsied and the joint fluid aspirate was cultured, confirming sporotrichosis. Histopathological assessment of the cysts that were subsequently excised from the dorsum of the hand and right knee joint also confirmed sporotrichosis. There were no features of active gout. A definitive diagnosis of multifocal systemic sporotrichosis was made. Within 8 weeks of commencing treatment with 200 mg itraconazole daily, there was resolution of the cutaneous lesions with residual post inflammatory hyperpigmentation. The pain and swelling of the wrist and knee joints resolved. At 9 months follow‐up, the patient was clinically free of sporotrichosis, but his high blood uric acid levels necessitated continuation of prophylactic allopurinol treatment.