Table of Contents
Definition / general | Diagnosis | Case reports | Treatment | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Electron microscopy descriptionCite this page: Gulwani H. Microsporidia. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/smallbowelmicrosporidiosis.html. Accessed January 22nd, 2021.
Definition / general
- Caused by Enterocytozoon bieneusi, an obligate intracellular protozoan that affects only enterocytes and Encephalitozoon intestinalis, which infects macrophages, fibroblasts, endothelial cells, enterocytes
- Both cause chronic diarrhea in patients with immunosuppression, HIV
Diagnosis
- Stool examination, PCR
Case reports
- 33 year old woman with myeloma, postautologous stem cell transplant and chemotherapy for relapse (Emerg Infect Dis 2012;18:1155)
- 43 year old man with pancreas / kidney transplant recipient and multiorgan system dissemination (Arch Pathol Lab Med 2004;128:e41)
Treatment
- Albendozole for E. intestinalis, nothing for E. bieneusi
Microscopic (histologic) description
- Minimal / no changes in mucosa but can find development spores as 1.5 mm dots in enterocytes
- May be surrounded by halos
- Also nucleated sporont present as 3 - 5 micron, rounded, basophilic structure often surrounded by a halo
Positive stains
Electron microscopy description
- Often helpful for diagnosis