Microsporidioses

Abstract

Microsporidia infect a wide range of invertebrates and vertebrates and were only rarely observed in humans until the mid‐1980s when these organisms became recognized as causes of opportunistic infections in persons with acquired immunodeficiency syndrome (AIDS) associated with persistent diarrhoea and wasting. Nowadays, microsporidioses are being identified more extensively among human populations that include children, travellers, the elderly and others who may be immunocompromised.

Keywords: microsporidia; opportunistic infection; emerging infection; Enterocytozoon; Encephalitozoon

Figure 1.

Ultrastructure of a microsporidian spore. The representative diagram (left panel) and transmission electron micrograph (right panel) of an E. cuniculi spore show an outer electron dense exospore (Ex) and an inner electron lucent endospore (En). The plasma membrane surrounds the cytoplasm. The anchoring disk, polarplast (Pp) and polarfilament (Pf) are components of the extrusion apparatus. The cytoplasm contains ribosomes and a posterior vacuole and depending on species one (monokaryon) nucleus (Nu) or two (diplokaryon) nuclei.

Figure 2.

Life cycle of the most common microsporidia that infect humans. Primary sites of infection commonly occur in the intestinal and respiratory tracts. Enterocytozoon bieneusi and Encephalitozoon intestinalis typically cause intestinal infections and Encephalitozoon species typically disseminate. Organisms are shed with faeces, urine and respiratory secretions and can then infect new hosts. Reproduced by permission of the DPDx: CDC's website for parasite identification; http://www.dpd.cdc.gov/DPDx/HTML/ImageLibrary/Microsporidiosis_il.htm

Figure 3.

Histopathology of Enterocytozoon bieneusi infection in rhesus macaques (Macacca mulatta). Top panel–Gallbladder (Animal DD52). The hyperplastic mucosa forms large folds and cysts lined by normal columnar epithelium. The lamina propria contains a mild‐to‐moderate lymphoplasmacytic infiltrate. Haematoxylin–eosin stain, bar=200 μm. Middle panel–Gallbladder (Animal DD52). Some but not all polychromatic 1×1.5 μm microsporidia spores are present in basal portions of the epithelial cytoplasm in two adjacent cells. One cell with a missing nucleus is in the process of sloughing into the lumen. Brown–Brenn Gram stain, bar=10 μm. Bottom panel–Gallbladder (Animal CA81). Polychromatic microsporidial spores free in the cytoplasm of an epithelial cell sloughing into the lumen and still containing remnants of the nucleus. An eosinophilic polar vacuole is prominent in basophilic staining spores. Brown–Brenn Gram stain, bar=10 μm (courtesy of Peter J. Didier, DVM, PhD).

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References

Bryan RT and Schwartz DA (1999) Epidemiology of microspridiosis. In: Wittner M and Weiss L (eds) The Microsporidia and Microsporidiosis, pp. 502–516. Washington DC: American Society for Microbiology Press.

Cali A and Takvorian M (1999) Developmental morphology and life cycles of the microsporidia. In: Wittner M and Weiss L (eds) The Microsporidia and Microsporidiosis, pp. 85–128. Washington DC: American Society for Microbiology Press.

Cotte L, Rabodonirina M, Chapuis F et al. (1999) Waterborne outbreak of intestinal microsporidiosis in persons with and without human immunodeficiency virus infection. Journal of Infectious Diseases 180: 2003–2008.

Coyle CM, Weiss LM, Rhodes LV 3rd et al. (2004) Fatal myositis due to the microsporidian Brachiola algerae, a mosquito pathogen. New England Journal of Medicine 351: 42–47.

Dascomb K, Frazer T, Clark RA, Kissinger P and Didier ES (2000) Microsporidiosis and HIV. Journal of Acquired Immune Deficiency Syndromes 24: 290–292.

Deplazes P, Mathis A and Weber R (2000) Epidemiology and zoonotic aspects of microsporidia of mammals and birds. Contributions to Microbiology 6: 236–260.

Desportes I, le Charpentier Y, Galian A et al. (1985) Occurrence of a new microsporidan: Enterocytozoon bieneusi n.g., n. sp., in the enterocytes of a human patient with AIDS. Journal of Protozoology 32: 250–254.

Didier ES and Weiss LM (2006) Microsporidiosis: current status. Current Opinion in Infectious Diseases 19: 485–492.

Didier ES, Stovall ME, Green LC et al. (2004) Epidemiology of microsporidiosis: sources and modes of transmission. Veterinary Parasitology 126: 145–166.

Didier ES, Maddry JA, Brindley PJ, Stovall ME and Didier PJ (2005) Therapeutic strategies for human microsporidia infections. Expert Review of Anti‐Infective Therapy 3: 419–434.

Franzen C and Müller A (1999a) Cryptosporidia and microsporidia – waterborne diseases in the immunocompromised host. Diagnostic Microbiology and Infectious Disease 34: 245–262.

Franzen C and Müller A (1999b) Molecular techniques for detection, species differentiation, and phylogenetic analysis of microsporidia. Clinical Microbiology Reviews 12: 243–285.

Franzen C, Müller A, Hartmann P and Salzberger B (2005a) Cell invasion and intracellular fate of Encephalitozoon cuniculi (Microsporidia). Parasitology 130(pt 3): 285–292.

Franzen C, Hartmann P and Salzberger B (2005b) Cytokine and nitric oxide responses of monocyte‐derived human macrophages to microsporidian spores. Experimental Parasitology 109: 1–6.

Friedberg DN and Ritterband DC (1999) Ocular microsporidiosis. In: Wittner M and Weiss L (eds) The Microsporidia and Microsporidiosis, pp. 293–314. Washington DC: American Society for Microbiology Press.

Garcia LS (2002) Laboratory identification of the microsporidia. Journal of Clinical Microbiology 40: 1892–1901.

Hayman JR, Southern TR and Nash TE (2005) Role of sulfated glycans in adherence of the microsporidian Encephalitozoon intestinalis to host cells in vitro. Infection and Immunity 73: 841–848.

Hutin YJ, Sombardier MN, Liguory O et al. (1998) Risk factors for intestinal microsporidiosis in patients with human immunodeficiency virus infection: a case‐control study. The Journal of Infectious Diseases 178: 904–907.

Katinka MD, Duprat S, Cornillot E et al. (2001) Genome sequence and gene compaction of the eukaryote parasite Encephalitozoon cuniculi. Nature 414: 450–453.

Keeling PJ, Fast NM, Law JS, Williams BA and Slamovits CH (2005) Comparative genomics of microsporidia. Folia Parasitologica 52: 8–14.

Khan IA, Moretto M and Weiss LM (2001) Immune responses to Encephalitozoon cuniculi infection. Microbes Infect 3: 401–405.

Khan IA and Didier ES (2004) Insights into the immune responses to microsporidia. In: Lindsay DS and Weiss LM (eds) Opportunistic Infections: Toxoplasma, Sarcocystis, and Microsporidia, World Class Parasites, Vol. 9, pp. 135–157. Boston, MA: Kluwer Academic Publishers.

Kotler D and Orenstein JM (1999) Clinical syndromes associated with microsporidiosis. In: Wittner M and Weiss L (eds) The Microsporidia and Microsporidiosis, pp. 258–292. Washington DC: American Society for Microbiology Press.

Larsson JI (2005) Molecular versus morphological approach to microsporidian classification. Folia Parasitologica 52: 143–144.

Leelayoova S, Subrungruang I, Rangsin R et al. (2005) Transmission of Enterocytozoon bieneusi genotype a in a Thai orphanage. American Journal of Tropical Medicine and Hygiene 73: 104–107.

Mathis A, Weber R and Deplazes P (2005) Zoonotic potential of the microsporidia. Clinical Microbiology Reviews 18: 423–445.

Miao YM, Awad‐El‐Kariem FM, Franzen C et al. (2000) Eradication of cryptosporidia and microsporidia following successful antiretroviral therapy. Journal of Acquired Immune Deficiency Syndromes 25: 124–129.

Moretto M, Weiss LM and Khan IA (2004) Induction of a rapid and strong antigen‐specific intraepithelial lymphocyte response during oral Encephalitozoon cuniculi infection. Journal of Immunology 172: 4402–4409.

Mungthin M, Suwannasaeng R, Naaglor T, Areekul W and Leelayoova S (2001) Asymptomatic intestinal microsporidiosis in Thai orphans and child‐care orkers. Transaction of the Royal Society of Tropical Medicine and Hygiene 95: 304–306.

Orenstein JM (2003) Diagnostic pathology of microsporidiosis. Ultrastructural Pathology 27: 141–149.

Smith H and Nichols RA (2006) Zoonotic protozoa‐food for thought. Parasitologia 48: 101–104.

Taupin V, Garenaux E, Mazet M et al. (2007) Major O‐glycans in the spores of two microsporidian parasites are represented by unbranched manno‐oligosaccharides containing {alpha}‐1,2 linkages. Glycobiology 17: 56–57.

Thurston‐Enriquez JA, Watt P, Dowd SE et al. (2002) Detection of protozoan parasites and microsporidia in irrigation waters used for crop production. Journal of Food Protection 65: 378–382.

Tumwine JK, Kekitiinwa A, Bakeera‐Kitaka S et al. (2005) Cryptosporidiosis and microsporidiosis in Ugandan children with persistent diarrhea with and without concurrent infection with the human immunodeficiency virus. American Journal of Tropical Medicine and Hygiene 73: 921–925.

Upadhya R, Zhang HS and Weiss LM (2006) System for expression of microsporidian methionine aminopeptidase type 2 (MetAP2) in the yeast Saccharomyces cerevisiae. Antimicrobial Agents and Chemotherapy 50: 3389–3395.

Van Gool T, Vetter JC, Weinmayr B et al. (1997) High seroprevalence of Encephalitozoon species in immunocompetent subjects. The Journal of Infectious Diseases 175: 1020–1024.

Vavra J and Larsson R (1999) Structure of the microsporidia. In: Wittner M and Weiss L (eds) The Microsporidia and Microsporidiosis, pp. 7–84. Washington DC: American Society for Microbiology Press.

Vossbrinck CR and Debrunner‐Vossbrinck BA (2005) Molecular phylogeny of the Microsporidia: ecological, ultrastructural and taxonomic considerations. Folia Parasitologica 52: 131–142.

Weber R, Deplazes P and Schwartz D (2000) Diagnosis and clinical aspects of human microsporidiosis. Contributions to Microbiology 6: 166–192.

Weiss LM (2000) Molecular phylogeny and diagnostic approaches to microsporidia. Contributions to Microbiology 6: 209–235.

Further Reading

Canning EU and Lom J (1986) The Microsporidia of Vertebrates. London: Academic Press.

Canning EU and Vavra J (2000) Phylum Microsporidia. In: Lee JJ, Leedale GF and Bradbury P (eds) The Illustrated Guide to the Protozoa, 2nd edn, pp. 39–126. Lawrence, KS, USA: Society of Protozoologists Press.

Desportes‐Livage I (2000) Biology of microsporidia. Contributions to Microbiology 6: 140–165.

Vossbrinck CR (2002) Microsporidians. Encyclopedia of Life Sciences. West Sussex, UK: John Wiley and Sons, Ltd, DOI 10.1038/npg.els.0001982.

Wittner M and Weiss LM (1999) The Microsporidia and Microsporidiosis. Washington DC: ASM Press.

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Hale‐Donze, Hollie, and Didier, Elizabeth S(Jul 2007) Microsporidioses. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0001930]