Encyclopedia of AIDS

Living Edition
| Editors: Thomas J. Hope, Douglas Richman, Mario Stevenson


  • Louis M. Weiss
  • Oren S. Weiss
  • Jacob G. Ludington
  • Honorine D. Ward
Living reference work entry
DOI: https://doi.org/10.1007/978-1-4614-9610-6_451-1


Microsporidia are a group of intracellular protists related to Fungi that can cause chronic diarrhea in patients with AIDS, but, depending on the particular species involved, can also infect many other organ systems with keratoconjunctivitis being a common nongastrointestinal manifestation.


The microsporidia are intracellular pathogens that infect both invertebrate and vertebrate hosts (Weiss and Becnel 2014). Microsporidia have a unique invasion organelle, the polar tube, that punctures host cells during invasion allowing transmission of this pathogen (Fig. 1). Given the wide host range of these organisms it is not surprising that they have been identified as human pathogens as they infect almost all animal phyla, including other protists. They were historically considered “primitive” protozoa; however, recent studies suggest that these organisms are related to the Fungi, either as a basal branch of the Fungi or as a sister group (Keeling 2009; Weiss and...


Sclerosing Cholangitis Interstitial Nephritis Chronic Diarrhea Ocular Infection Granulomatous Hepatitis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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The work was supported by NIH grants (to LMW) AI093315 and AI093220.


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© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Departments of PathologyAlbert Einstein College of MedicineBronxUSA
  2. 2.Departments of MedicineAlbert Einstein College of MedicineBronxUSA
  3. 3.Department of Systems and Computational BiologyAlbert Einstein College of MedicineBronxUSA
  4. 4.Tufts University Sackler School of Graduate Biomedical Sciences and Tufts Medical CenterBostonUSA