Anterior Segment Optical Coherence Tomography Images in Microsporidial Keratoconjunctivitis.

PURPOSE: To describe the findings of anterior segment optical coherence tomography (AS-OCT) in patients with microsporidial keratoconjunctivitis. METHODS: The observational study included 13 eyes from 13 patients. Slit-lamp photography and AS-OCT were performed using the Swept source OCT before corneal scraping. All cases were positive for Gram-chromotrope (modified trichrome) staining for Microsporidia spp. RESULTS: Three significant AS-OCT findings were observed. First, hyperreflective dots were limited to the epithelial layers of the cornea, and second, there were no extensions into the stromal layer in all cases. Last, hyperreflective dots slightly raised above the epithelial surface were observed in most cases (12/13%, 92.3%). CONCLUSIONS: AS-OCT represents an alternative, noninvasive tool to diagnose microsporidial keratoconjunctivitis, especially if corneal scraping is not possible.

In vivo confocal microscopic characteristics of microsporidial keratoconjunctivitis in immunocompetent adults.

BACKGROUND/AIMS: To describe in vivo confocal microscopy (IVCM) features of microsporidial keratoconjunctivitis in immunocompetent adult patients. METHODS: Patients suspected clinically to be suffering from microsporidial keratoconjunctivitis (ie, presence of unilateral follicular and/or papillary conjunctivitis in conjunction with multifocal, coarse corneal epitheliopathy) were subjected to IVCM with the Rostock Cornea Module of the Heidelberg Retinal Tomograph 3, and combined potassium hydroxide and calcofluor white (KOH+CFW) staining of the corneal scrapings, to detect the microsporidial spores. Detection of spores in corneal scrapings was considered as being confirmatory for microsporidial infection. RESULTS: Of a total of 10 patients screened, 8 patients (7 male, 1 female) demonstrated the presence of oval, non-budding microsporidial spores which fluoresced bluish white on combined KOH+CFW staining. IVCM in seven of these eight patients demonstrated multiple rosette-like clusters/plaque of epithelial cells, within which hyper-reflective, pinpoint oval intracellular bodies (similar to the spores seen on microbiological staining) were present. One patient who had been on prolonged treatment with topical steroids showed the presence of the oval bright bodies scattered diffusely within the epithelial cells, without rosette formation. CONCLUSIONS: In microsporidial keratoconjunctivitis, IVCM is able to detect presence of bright, ovoid spore-like structures in the epithelial layers. Epithelial rosette formation is another characteristic feature seen in a majority of these patients. These features may be used as a reliable screening tool for starting therapy, precluding the need for corneal scrapings in a majority of patients.

Chronic microsporidian infection of the nasal mucosae, sinuses and conjunctivae in HIV disease.

A case of chronic infection of the nasal mucosae, sinuses and conjunctivae with a microsporidian parasite in association with HIV infection and immune deficiency is reported. This microsporidian resembles both Encephalitozoon cuniculi and the newly described Encephalitozoon hellem by electron microscopy. This occurred in an adult male resident in the UK with no history of foreign travel. Although there are previous descriptions of conjunctival infections from the USA, this is the first description of infection of the nasal epithelium. Further studies are underway to classify this protozoan.