Parasitology Research

, Volume 102, Issue 5, pp 945–950 | Cite as

An extraordinary endocytobiont in Acanthamoeba sp. isolated from a patient with keratitis

  • P. ScheidEmail author
  • L. Zöller
  • S. Pressmar
  • G. Richard
  • R. Michel
Original Paper


In the present article, the detection and the development of a parasitic endocytobiont within host amoebae (Acanthamoeba sp.) recently isolated from the contact lens and the inflamed eye of a patient with keratitis is presented. An otherwise healthy 55-year-old female patient presented with keratitis in her inflamed left eye. She was a contact lens wearer and had no history of a corneal trauma. Acanthamoebae as well as other smaller free-living amoebae could be detected from the fluid of the contact lens storage cases by culture methods. A successful therapy could be provided consequently. Two of these Acanthamoeba strains showed intracellular aggregating organisms. Within 2 to 3 days, the host amoebae ruptured, and numerous microorganisms were released. We succeeded in detecting the mechanism of infection and intrusion of this organisms by using light and electron microscopy. Infection with this endocytobiont is a suitable model for studying the host–parasite relations while the parasites use their hosts as so-called Trojan horses (see Barker, Lambert, Brown, Infect Immun 61:3503–3510, 1992).


Keratitis Cabral Allergic Contact Dermatitis Food Vacuole Acanthamoeba Keratitis 
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.



We like to thank Dr. B. Hauröder for her help and assistance to obtain the impressive electron microscopical records.


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • P. Scheid
    • 1
    Email author
  • L. Zöller
    • 1
  • S. Pressmar
    • 2
  • G. Richard
    • 2
  • R. Michel
    • 1
  1. 1.Laboratory of Medical ParasitologyCentral Institute of the Bundeswehr Medical Service KoblenzKoblenzGermany
  2. 2.Universitätsklinikum Hamburg-EppendorfKlinik und Poliklinik für AugenheilkundeHamburgGermany

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