1/9. Corneal microsporidiosis. Report of case, including electron microscopic observations.OBJECTIVE: To report a case of corneal stromal infection caused by a protozoon of the genus microsporidia:, including clinical, histopathologic, and electron microscopic observations. DESIGN: Case report. methods: light and electron microscopy studies were performed on keratectomy specimens from a 67-year-old immunocompetent man who had a unilateral chronic stromal keratitis that was refractory to medical treatment. Initial corneal biopsy followed by lamellar and penetrating keratoplasty were performed on the patient. All the specimens were studied histopathologically. RESULTS: light microscopy of the corneal biopsy and the subsequent keratectomy specimens demonstrated myriad small, round to oval microsporidial organisms measuring 3.5 to 5.0 micrometer in length that stained positively with the periodic acid-Schiff, Grocott-methenamine silver, and acid-fast methods and were gram positive. Electron microscopic observations demonstrated viable blastospores that had a thin osmiophilic outer cell wall and contained 11 to 13 coils of the filament. The light and electron microscopic features, the tinctorial characteristics, and the selective corneal stromal involvement are consistent with microsporidial keratitis. CONCLUSIONS: microsporidiosis should be considered in the differential diagnosis of a culture-negative stromal keratitis refractory to medical treatment. The diagnosis can be easily established based on the morphologic features of the protozoa in the keratectomy specimens. No effective medical treatment for the stromal disease is available. Full-thickness keratoplasty is suggested because, in our patient, lamellar keratoplasty did not preclude recurrence of the disease.- - - - - - - - - - ranking = 1keywords = keratitis (Clic here for more details about this article) |
2/9. Microsporidial keratoconjunctivitis in a healthy contact lens wearer without human immunodeficiency virus infection.PURPOSE: To present a rare case of microsporidial keratoconjunctivitis in an otherwise healthy contact lens wearer without human immunodeficiency virus infection who responded to treatment with systemic albendazole and topical fumagillin. DESIGN: Interventional case report. METHOD: A cornea epithelial scraping from a man with unilateral keratoconjunctivitis previously treated with topical steroids was evaluated by modified trichome staining. MAIN OUTCOME MEASURES: The patient was evaluated for his symptoms, visual acuity, clinical observations, and pathologic examination of corneal scrapes. RESULTS: Modified trichome staining of an epithelial corneal scraping revealed pinkish to red organisms characteristic of microsporidia. Results of a human immunodeficiency virus (hiv) enzyme-linked immunosorbent assay test were negative. The symptoms of ocular discomfort and clinical signs of keratoconjunctivitis resolved after 2 months of treatment with albendazole and topical fumagillin. CONCLUSIONS: Ocular infection with microsporidia, although classically occurring in patients with hiv infection, may occur rarely in healthy individuals, especially if previously treated with systemic immune suppression or topical steroids. Microsporidial keratoconjunctivitis should be considered in the differential diagnosis of a contact lens wearer with atypical multifocal diffuse epithelial keratitis.- - - - - - - - - - ranking = 0.33333333333333keywords = keratitis (Clic here for more details about this article) |
3/9. Bilateral microsporidial keratoconjunctivitis in an immunocompetent non-contact lens wearer.PURPOSE: To describe an immunocompetent male with bilateral microsporidial keratoconjunctivitis who responded to treatment with albendazole, propamidine, and fumagillin. methods: Corneal and conjunctival epithelial scrapings from a man with bilateral keratoconjunctivitis previously treated with topical corticosteroids were evaluated by Gram stain and by fluorescence microscopy. RESULTS: Gram stain and fluorescence microscopy of corneal epithelial scraping revealed organisms characteristic of microsporidia. Results of human immunodeficiency virus antibody testing were reported as nonreactive. Symptoms of ocular discomfort and clinical signs of keratoconjunctivitis resolved after five weeks of treatment that included systemic albendazole and topical propamidine isethionate 0.1% and fumagillin bicyclohexylammonium salt. A follow-up conjunctival scraping failed to detect any residual organisms 2 weeks after cessation of all treatment. CONCLUSION: Microsporidial ocular infection occurred in an immunocompetent non-contact lens wearer. Microsporidial keratoconjunctivitis should be considered in any individual with atypical multifocal diffuse epithelial keratitis, regardless of immune status or recent history of contact lens wear.- - - - - - - - - - ranking = 0.33333333333333keywords = keratitis (Clic here for more details about this article) |
4/9. Microsporidial keratoconjunctivitis in healthy individuals: a case series.PURPOSE: To present a series of 6 cases of microsporidial keratoconjunctivitis in healthy, nonimmunocompromised individuals. DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: Six individuals with unilateral keratoconjunctivitis. methods: cornea epithelial scrapings were taken and evaluated by modified trichome staining. blood was taken for human immunodeficiency virus (hiv) enzyme-linked immunosorbent assay in all cases and for CD4 and CD8 T-lymphocyte counts in 5 cases. MAIN OUTCOME MEASURES: The individuals were evaluated based on symptoms, visual acuity, slit-lamp biomicroscopy, and pathologic examination of the corneal scrapings. RESULTS: All cases occurred in men whose ages ranged from 16 to 37 years. Initial symptoms included unilateral pain and redness. All experienced subsequent worsening of symptoms and blurring of vision after using topical steroids prescribed by general practitioners. Slit-lamp biomicroscopy revealed coarse, multifocal, punctate epithelial keratitis in all 6 cases, anterior stromal infiltrates in 2 cases, with accompanying conjunctivitis in all cases. Modified trichrome staining of corneal epithelial scrapes revealed pinkish to red spores characteristic of microsporidia in all cases. Results of an hiv enzyme-linked immunosorbent assay were negative in all cases, and CD4 and CD8 T-lymphocyte counts and ratios were normal in all 5 tested cases. On diagnosis, topical steroid therapy was stopped in all cases. Treatment with topical Fumidil B (bicyclohexylammonium fumagillin; Leiter's Park Ave pharmacy, San Jose, CA) together with oral albendazole was given in 3 cases, oral albendazole alone in a single case, and broad-spectrum antibiotic treatment with topical norfloxacin or chloramphenicol in two cases. Two cases had keratic precipitates with mild cellular activity in the anterior chamber and one such case was restarted subsequently on topical steroids. All six cases showed resolution of epithelial keratitis but with residual visually inconsequential subepithelial scars by the end of 1 month of treatment. CONCLUSIONS: Microsporidial keratoconjunctivitis can occur more commonly than expected in healthy, nonimmunocompromised individuals. Topical steroids seem to contribute to the persistence of this infection and may be a predisposing factor in these cases by creating a localized immunocompromised state. The clinical course is variable and may be self-limiting with cessation of topical steroid use.- - - - - - - - - - ranking = 0.66666666666667keywords = keratitis (Clic here for more details about this article) |
5/9. Ultrastructural examination of two cases of stromal microsporidial keratitis.Two cases with chronic stromal keratitis are described in immunocompetent hosts where the diagnosis was originally thought to be herpetic or adenoviral disease. light microscopy and ultrastructural examination of corneal tissue by electron microscopy were performed following penetrating keratoplasty (case 1) and corneal biopsy (case 2). Specimens from both cases were analysed for viral identification by PCR. Two different species of microsporidia were identified. Case 1 represents the fourth reported case of corneal stromal vittaforma corneae where the spores measured 3.3 x 1.4 microm, arranged in characteristic linear groups of about four to eight. Each spore contained a diplokaryotic nucleus and a single row of ten polar tube coils. By contrast, case 2 is the first reported case of stromal keratitis caused by Trachipleistophora hominis. In this case, spores measured 4 x 2.4 microm, located typically within packets. In this species, the polar tube was arranged as a single row of about 10-13 profiles. Viral dna could not be amplified by PCR. In conclusion, microsporidial stromal keratitis should be considered in culture-negative cases refractory to medical therapy. As microbiological culture techniques are unsuccessful, diagnosis may only be established following histopathological and ultrastructural examination of corneal tissue.- - - - - - - - - - ranking = 2.3333333333333keywords = keratitis (Clic here for more details about this article) |
6/9. Chronic microsporidial stromal keratitis in an immunocompetent, non-contact lens wearer.An 82-year-old healthy man with unilateral chronic stromal keratitis, initially diagnosed to have viral keratitis and refractory to medical therapy, showed numerous oval, microsporidial organisms, measuring 4-5 m in length in the corneal biopsy. Penetrating keratoplasty, followed by treatment with systemic albendazole and topical propamidine isethionate resulted in resolution of the infection. Electron microscopy of the keratoplasty specimen demonstrated sporoblasts with diplokaryotic nuclei and multiple coils of the filament. The light and electron microscopic features were consistent with microsporidial keratitis.- - - - - - - - - - ranking = 2.3333333333333keywords = keratitis (Clic here for more details about this article) |
7/9. Is microsporidial keratitis an emerging cause of stromal keratitis? A case series study.BACKGROUND: Microsporidial keratitis is a rare cause of stromal keratitis. We present a series of five cases of microsporidial keratitis from a single centre in southern india with microbiologic and histopathologic features. CASE PRESENTATION: Patient charts of five cases of microsporidial stromal keratitis diagnosed between January 2002 and June 2004 were reviewed retrospectively for clinical data, microbiologic and histopathologic data. The presence of microsporidia was confirmed by special stains on corneal scrapings and/or corneal tissues, and electron microscopy. All patients were immunocompetent with a preceding history of trauma in three. Four patients presented with unilateral, small, persisting deep stromal infiltrates, of uncertain etiology, in the cornea, which were not responding to conventional antimicrobial treatment and required penetrating keratoplasty in three. Fifth case was unsuspected and underwent keratoplasty for post-traumatic scar. Three of five cases were diagnosed on corneal scrapings, prior to keratoplasty, while two were diagnosed only on histology. The microsporidia appeared as oval well defined bodies with dense staining at one pole. None of the patients showed recurrence following keratoplasty. CONCLUSION: microsporidia, though rare, should be suspected in chronic culture-negative stromal keratitis. Organisms could lie dormant without associated inflammation.- - - - - - - - - - ranking = 4.3333333333333keywords = keratitis (Clic here for more details about this article) |
8/9. keratitis caused by Trachipleistophora anthropopthera.We report a case of intrastromal keratitis in a 42-year-old male with underlying human immunodeficiency virus-1 infection. Numerous microsporidial spores were found from corneal biopsy. Ultrastructural studies of corneal tissues revealed dimorphic sporophorous vesicles containing characteristic spores belonging to Trachipleistophora anthropopthera. infection could be controlled by penetrating keratoplasty but not by topical fumagillin and systemic albendazole per se. This is the first report of human keratitis caused by this organism.- - - - - - - - - - ranking = 0.66666666666667keywords = keratitis (Clic here for more details about this article) |
9/9. diagnosis of microsporidial keratitis by confocal microscopy and the chromatrope stain.PURPOSE: To illustrate the value of confocal microscopy and chromatrope stain in the diagnosis of microsporidial keratitis. methods: In vivo confocal microscopy was performed on a man with the human immunodeficiency virus who had severe bilateral epithelial keratitis refractory to topical antibacterial medications. The results were compared to conjunctival scrapings stained with the chromatrope-based Weber stain. RESULTS: Confocal microscopy demonstrated many small, intraepithelial opacities of the corneal epithelium, which were suggestive of microsporidia. Results of the chromatrope stain of conjunctival scrapings confirmed the diagnosis of microsporidial keratitis. CONCLUSIONS: Rapid diagnosis allowed prompt initiation of topical fumagillin, which permitted rapid, long-term control of the symptoms of microsporidial keratitis.- - - - - - - - - - ranking = 2.6666666666667keywords = keratitis (Clic here for more details about this article) |