Refractory Candida orthopsilosis endocarditis in a hemodialysis patient: The role of species-level identification and surgical source control.

PURPOSE: Candida orthopsilosis endocarditis is rare and underdiagnosed due to the inability of conventional biochemical platforms to achieve species-level identification within the Candida parapsilosis complex.

METHODS

We report a 60-year-old hemodialysis-dependent woman with diabetes mellitus and chronic kidney disease who developed catheter-related fungemia progressing to infective endocarditis.

RESULTS

C. orthopsilosis was identified by MALDI-TOF mass spectrometry. Broth microdilution per BrCAST/EUCAST demonstrated susceptibility to amphotericin B, fluconazole, and anidulafungin. Transesophageal echocardiography (TEE) revealed a mobile tricuspid valve vegetation fulfilling modified Duke Criteria for definite infective endocarditis. Despite antifungal therapy, blood cultures remained positive and septic pulmonary embolism developed. Surgical valve replacement achieved microbiological clearance within 24 hours; C. orthopsilosis was confirmed in excised tissue. Fluconazole step-down completed a six-week course.

CONCLUSION

MALDI-TOF-guided species identification, susceptibility-directed echinocandin therapy, and timely surgical source control constitute an effective management framework for Candida endocarditis, achieving complete microbiological clearance despite severe systemic complications.