Microsporidia

Microsporidia are unicellular, obligate intracellular, mitochondria-free fungi of which there are about 12200 species. Microsporidia were formerly classified as protozoa. In immunocompetent people they are pathogens of microsporidiosis

Microsporidia can reach a size of a few µm (2-12 µm). Microspora usually parasitize intracellularly in representatives of many animal strains.

Only a few pathogens appear as pathogens:

• Enterocytozoon bieneusi
• intestinal encephalitozoon
• Encephalitozoon cuniculi
• Microsporidium africanum
• vittaforma corneum

Transmission occurs by uptake of unicellular, environmentally stable spores from animals to humans by smear infection.

Especially in HIV-infected persons (T-helper number a100/μl) the clinical picture of microsporidiosis can develop, which manifests itself through a chronic aqueous diarrhoea with malabsorption, gfls. cholangitis, hepatitis, keratoconjunctivitis, peritonitis, sinusitis. Dissemination with encephalitis is very rare.

1. Han B et al (2018) Therapeutic targets for the treatment of microsporidiosis in humans. Expert Opinion Ther Targets 22:903-915.
2. Leroy J et al (2018) Case Report: Ocular Microsporidiosis: Case in a Patient Returning from India and Review of the Literature. At J Trop Med Hyg 99:90-93.
3. Ramanan P et al (2014) Extraintestinal microsporidiosis. J Clin Microbiol 52:3839-3844.