Pleurostomophora richardsiae– An Insidious Fungus Presenting in a Man 44 Years After Initial Inoculation: A Case Report and Review of the Literature

1The University of Ottawa, The Ottawa Hospital, Ottawa; 2Mount Sinai Hospital; 3University of Toronto; 4Public Health Laboratories, Department of Laboratory Medicine and Pathobiology, Toronto; 5Lakeridge Health, Oshawa, Ontario Correspondence: Dr Jeremy Levenstadt, 95 Bayly Street West, #200, Ajax, Ontario L1S 7K8. Telephone 647-404-5545, fax 905-686-9222, e-mail jeremy.levenstadt@gmail.com case presentation A 54-year-old man from Guyana presented with a painful, nonerythematous, subcutaneous nodule on his right patella at the site of a remote injury. The patient fell while climbing a coconut tree at 10 years of age, 44 years before presentation. The fall caused him to land on the stump of a ‘black sage tree’ injuring his right patella. Multiple small splinters from the stump penetrated his skin over and around his patella, which were removed shortly after the initial injury. The patient reported a significant amount of purulent discharge that eventually subsided. He was never treated with antibiotics. For approximately the next 40 years, the patient reported a history of knee swelling that dramatically increased in recent years. He reported no recent trauma. He experienced no fever, chills, sweats or recent weight loss. The patient was a nonsmoker, did not drink alcohol and had no history of injection drug use. On examination, he was afebrile and looked well. There was no lymphadenopathy. There was a 4 cm × 4 cm nonerythematous, indurated nodule on the anterior aspect of the right patella. There was no joint effusion; however, there was a prepatellar bursitis. The lesion was not adherent to the patella and moved freely. Complete blood count, glucose level, renal function, hepatic transaminases and serum protein electrophoresis were all normal. He was HIV seronegative. A radiograph of the right knee did not demonstrate any foreign body or bone destruction. The prepatellar fluid was aspirated, producing thick fluid, tan-red in colour. Cytological analysis of the fluid showed histiocytes with inflammatory cells. A Gram stain of the fluid did not demonstrate any pus cells or bacteria. Routine aerobic and anaerobic bacterial cultures were negative for bacterial growth. Mycobacterial smears and cultures were also negative. A direct mycology smear using calcofluor white was negative, but two colonies of a filamentous fungus were noted both on the routine sheep blood agar and chocolate agar culture plates after four days of incubation.