Amebic Keratitis in a Wearer of Disposable Contact Lenses due to a Mixed Vahlkampfia and Hartmannella Infection
| Autor: | John Hay, William R. Lee, Dorothy A. Aitken, Colin M. Kirkness, Frances B. Kinnear, David V. Seal |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Adult
Male Pathology medicine.medical_specialty Antifungal Agents Antibodies Protozoan Antigens Protozoan Lobosea Vahlkampfia Keratitis Microbiology Cornea parasitic diseases medicine Animals Humans Eye Infections Parasitic Disposable Equipment Fluorescent Antibody Technique Indirect Hartmannella Amoebida biology Amebiasis Eye infection Contact Lenses Hydrophilic biology.organism_classification medicine.disease eye diseases Acanthamoeba Contact lens Ophthalmology Protozoa Rabbits Keratoplasty Penetrating |
| Zdroj: | Ophthalmology. 103:485-494 |
| ISSN: | 0161-6420 |
| Popis: | Purpose: To support the hypothesis that Acanthamoeba is not a unique cause of amebic keratitis, we report a case of amebic keratitis in which viable Acanthamoeba could not be isolated from corneal tissue. Vahlkampfia and Hartmannella , two other genera of free-living ameba, were isolated, however, using prolonged culture. Methods: A 24-year-old wearer of soft contact lenses had keratitis. Extensive histologic and microbiologic investigations were performed on corneal scrape, biopsy, and keratoplasty tissue. Contact lenses, storage case, and the home water supply, where contact lens hygiene was practiced, were examined for the presence of micro-organisms. Results: No viruses, pathogenic bacteria, or fungi were detected from corneal tissue samples. Amebae were observed using light and electron microscopy, but these could not be unequivocally classified using immunocytochemical staining. Viable Vahlkampfia and Hartmannella , but no Acanthamoeba , were isolated from the corneal biopsy sample. Indirect immunofluorescence with a range of polyclonal rabbit antisera raised against axenically cultivated stains of the three amebal genera was unhelpful because of cross-reactivity. A diverse range of micro-organisms was present within the storage case, including the three ameba) species. Amebic cysts also were associated with the contact lens. Conclusion: A mixed non Acanthamoeba amebic keratitis has been identified in a wearer of soft contact lenses where lack of storage case hygiene provided the opportunity for the free-living protozoa Vahlkampfia and Hartmannella to be introduced to the ocular surface. When Acanthamoeba -like keratitis occurs, but where Acanthamoeba cannot be isolated using conventional laboratory culture methods, alternate means should be used to identify other amebae that may be present. Polyclonal immunofluorescent antibody staining was unreliable for generic identification of pathogenic free-living amebae in corneal tissue. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|