Identification of Anncaliia algerae in Ascites in an Immunosuppressed Patient, China

Abstract

Anncaliia algerae, a microsporidium, has risen to prominence as an opportunistic pathogen, particularly afflicting immunocompromised individuals grappling with conditions such as rheumatoid arthritis, organ transplantation, and hematologic malignancy. Surprisingly, despite its recognized impact, the identification of A. algerae in ascitic fluid has not hitherto been documented. Worthwhile, we pinpointed A. algerae as the probable instigator of ascitic accumulation in a patient with a history of acute myeloid leukemia and extended periods of immunosuppressive therapy. For the patient we described, there were no signs of A. algerae-related infections such as myositis, vocal cord involvement, or disseminated infection. The presence of A.algerae was finally identified by next-generation metagenomic sequencing analysis of the ascitic fluid. The clinical presentation, characterized by elevated C-reactive protein (CRP) levels (110.7 mg/L), diminished platelet count (48 ×109/L), abdominal distension secondary to ascitic fluid accumulation, and lower limb pain, showed marked improvement following a 4-day sulfamethoxazole/trimethoprim (SMZ/TMP) and albendazole regimen. Despite this promising response, the patient tragically succumbed to aspiration of vomitus. This case underscored the importance of considering rarer organisms such as A. algeare infection, in immunocompromised patients presenting with unexplained ascites accumulation. It highlighted the potential effectiveness of SMZ/TMP and albendazole in managing such cases. Further research is warranted to elucidate optimal management strategies and improve outcomes in similar clinical scenarios.