Language
English
Publication Date
7-1-2025
Journal
ASM Case Reports
DOI
10.1128/asmcr.00014-24
PMID
41245671
PMCID
PMC12466012
PubMedCentral® Posted Date
4-2-2025
PubMedCentral® Full Text Version
Post-print
Abstract
Background: Mycetohabitans [Burkholderia] rhizoxinica is an endosymbiotic bacteria of Rhizopus microsporus that normally causes rice seedling blight. In our case report, we present one of the first known cases of concomitant bacteremia with M. rhizoxinica and invasive mold infection due to Rhizopus spp. in an immunocompromised child.
Case summary: A 3 year old male recently diagnosed with B-cell acute lymphoblastic leukemia developed febrile neutropenia. His workup was significant for invasive fungal sinusitis due to Exserohilum spp. based on histopathology and culture, a right middle lobe infiltrate, and a blood culture positive for gram-negative coccobacilli, later identified as M. rhizoxinica. Additionally, metagenomics next-generation sequencing was positive for R. microsporus as was broad-range fungal PCR testing of a lung biopsy sample. His surgical treatments included sinus debridement and a near total right pneumonectomy, and his antimicrobial treatment included 10 days of cefepime for his bacteremia, 4 weeks of liposomal amphotericin B, 4 weeks of micafungin following his pneumonectomy, and approximately 12 months of posaconazole.
Conclusion: This case highlights the association of M. rhizoxinica with Rhizopus spp., wherein the isolation of M. rhizoxinica led to a high index of suspicion of Rhizopus infection in an immunocompromised patient who developed bacteremia with a slow-growing, oxidase positive, gram-negative bacteria not able to be identified by traditional identification methods.
Keywords
Mycetohabitans rhizoxinica, Rhizopus, Exserohilum, endofungal bacteria, sinonasal fungal disease, fungal pneumonia, invasive fungal disease, immunocompromised host
Published Open-Access
yes
Recommended Citation
Orbea, Marisa; Fortini, Mary; Amerson-Brown, Megan H; et al., "Mycetohabitans rhizoxinica Bacteremia in the Setting of Invasive Fungal Disease in an Immunocompromised Patient" (2025). Faculty and Staff Publications. 5970.
https://digitalcommons.library.tmc.edu/baylor_docs/5970