The Brief Case: A Case of Prosthetic Valve Endocarditis Due to Lodderomyces elongisporus

CASE A46-year-old male was admitted to the neurosurgery intensive care unit with a diagnosis of intracerebral hemorrhage with intraventricular bleeding. His history was notable for replacement of his aortic valve with a mechanical prosthesis approximately 2 years prior, for which he was on chronic anticoagulation and antiplatelet therapy. The morning of presentation, he complained of chest pain after using cocaine and heroin. Paramedics were called and noted that the patient was unresponsive and possibly seizing. On physical exam, the patient had a regular cardiac rate and rhythm and was being mechanically ventilated; all other systems were normal. The patient had a history of injection drug use, and his providers noted “track marks” on his arms, suggesting his use was ongoing. Computed tomography of his head showed a large, left posterior parieto-occipital intracranial hemorrhage with intraventricular bleeding and cerebral edema resulting and a 1.1-cm midline shift to the right. Blood cultures were drawn on admission and hepatitis C antibody testing was reactive. Cerebral angiography showed a distal, left middle cerebral artery mycotic aneurysm, and the patient was taken for embolization by vascular interventional radiology. Transthoracic echocardiography did not show any abnormalities, but a transesophageal echocardiogram later the same day showed an echodense lesion adherent to the patient’s prosthetic aortic valve that was concerning for infectious endocarditis. He was started on empirical antibacterial therapy with vancomycin and cefepime. Two days into the patient’s hospital stay, one aerobic bottle out of two blood culture sets became positive. Gram staining of the positive bottle revealed a budding yeast (Fig. 1A). Probable organisms for his disseminated infection included Candida or Cryptococcus, though epidemiologically there was greater concern for Candida. Micafungin was added empirically to cover for candidiasis, pending final identification of the organism. One day later, colony growth was observed on chocolate agar (not pictured), colistin-nalidixic agar (CNA) (Fig. 1B), and BBL CHROMagar Candida medium (Becton, Dickinson and Company, Sparks, MD) (Fig. 1C). Colonies were cream-colored and opaque after 36 h of growth on CNA. CHROMagar Candida medium revealed turquoise colonies after 48 h of growth. Using matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry Vitek MS (bioMérieux, Durham, NC), the organism was identified as Lodderomyces elongisporus, and this was confirmed through Sanger sequencing of the internal transcribed spacer (ITS) region of fungal ribosomal DNA. The ITS region is a conserved region of the fungal genome between the small subunit 18S rRNA gene and the large subunit 28S rRNA gene that can be used to identify fungi to the species level. Citation Thompson CM, Warner N, Hurt CB, Alby K, Miller MB. 2021. The Brief Case: A case of prosthetic valve endocarditis due to Lodderomyces elongisporus. J Clin Microbiol 59:e01225-20. https://doi.org/10.1128/JCM . 01225-20. Editor Carey-Ann D. Burnham, Washington University School of Medicine Copyright © 2021 American Society for Microbiology. All Rights Reserved. Address correspondence to Cecilia M. Thompson, cecilia.thompson@tricore.org. For answers to the self-assessment questions and take-home points, see https://doi.org/ 10.1128/JCM.01227-20 in this issue. Published 21 January 2021