Where the infection is isolated rather than the specific species correlates with adherence strength, whereas biofilm density remains static in clinically isolated Candida and arthroconidial yeasts

A Case of Pulmonary Infection Due to Magnusiomyces capitatus in a Non-Immunocompromised Patient with Cerebral Palsy

Background

Magnusiomyces capitatus (M. capitatus) is a dimorphic opportunistic fungus that is a rare yeast and rarely reported in Asia. Owing to the absence of established clinical breakpoints, the treatment of this fungus poses challenges.

Case Presentation

We report a rare case of a young, non-immunocompromised man with cerebral palsy, spinal deformity, and pulmonary M. capitatus infection. The patient's condition improved after treatment with voriconazole and became stable.

Conclusion

M. capitatus infection is commonly associated with hematologic tumors and compromised immunity. Reports of M. capitatus infection in patients with non-immunocompromised host are uncommon. Insufficient understanding of these fungi may lead to underdiagnosis of fungal infection and clinical misdiagnosis, potentially resulting in delayed treatment and increased mortality.

Saprochaete/Magnusiomyces: identification, virulence factors, and antifungal susceptibility of a challenging rare yeast

Saprochaete/Magnusiomyces is among rare yeasts which might emerge as causes of breakthrough infections and nosocomial outbreaks. Identification to the species level might be a challenge in clinical laboratories. Data on virulence factors are scarce and antifungal susceptibility testing methodology is not definite. The aim of this study was to confirm species identification of clinical Saprochaete/Magnusiomyces isolates, find out their virulence factors, and obtain antifungal minimum inhibitory concentrations with two reference methods. Of the 57 isolates included, 54 were Saprochaete capitata and four were Saprochaete clavata as identified by ID32C, MALDI-TOF MS, and sequencing. When tested using phenotypic methods, all isolates were negative for coagulase, hemolysis, acid proteinase, and phospholipase, 56.1% were positive for esterase, and 19.3% had intermediate surface hydrophobicity. All isolates formed biofilms, with 40.4% of the isolates producing more biomass than biofilm-positive reference strain Candida albicans MYA-274. Antifungal susceptibility testing needed an adjusted spectrophotometric inoculum than recommended in reference methods for Candida/Cryptococcus. In conclusion, Saprochaete/Magnusiomyces species could be identified using methods available in the clinical laboratories. Despite the disadvantages of the phenotypic methods, esterase positivity was observed for the first time. A high biomass production was observed in biofilms. The need for standardization of antifungal susceptibility testing was brought to attention.