Autopsy findings in a case of Lomentospora prolificans fungemia in myelodysplastic syndrome

Abstract

Abstract Background Lomentospora prolificans is a soil-, plant-, or animal-borne mold that can affect immunocompromised hosts. Most L. prolificans infections are identifieable in the bloodstream. L. prolificans fungemia has never been reported in an autopsy. Case report We treated a 79-year-old man with myelodysplastic syndrome (MDS), subtype MDS-EB-1. Due to a low MDS risk status, the patient was being monitored in an outpatient setting. He developed pneumonia and was hospitalized for treatment. He was treated empirically with meropenem and vancomycin, which did not improve the patient's symptoms or clinical data. We diagnosed the patient with bronchitis obliterans organizing pneumonia because the culture report of the lavage fluid obtained through bronchofiberscopy (BFS) was negative. We administered methylprednisolone (mPSL) at 500 mg/day for 3 days minipulse therapy on day 10, followed by high dose mPSL. The patient’s condition improved slightly but worsened again during the corticosteroid tapering process. A second BFS was performed on day 28, which detected L. prolificans on lavage culture. We treated the patient with voriconazole as per the literature, but it did not improve the condition, and on day 46, the patient died of multiple organ failure due to L. prolificans fungemia. An autopsy revealed macroscopically white nodules and foci of fungal mass abscess pathologically in systemic tissues, including the lung, heart, kidney, thyroid gland, and peritoneum. Discussion Diagnosing the rare invasive infection caused by L. prolificans in immunosuppressed patients with hematologic malignancies is difficult. We hope this case report contributes to understanding the pathogenesis of fatal L. prolificans fungemia.