Evaluation of corneal scraping smear examination methods in the diagnosis of XXXX : a survey of eight years of laboratory experience.

@entity1 @entity3071 @entity1036 @entity4014 @entity364
PURPOSE: To determine the sensitivity, specificity, and predictive values of Gram and @entity4014 with calcofluor white ( @entity3071 +CFW) stains in the diagnosis of early and advanced microbial @entity1036 , a retrospective analysis of comparative data from a prospectively collected database was done. METHODS: @entity1 with nonviral microbial @entity1036 seen at L.V. Prasad Eye Institute between February 1991 and December 1998 were included in the study. The type of bacteria seen on Gram stain was determined from 251 corneal scrapings from @entity1 with @entity1036 and 841 corneal scrapings from @entity1 with advanced @entity1036 . The presence of fungi in corneal scrapings was determined by @entity3071 +CFW stain of 114 and 363 scrapings from @entity1 with early and advanced @entity1036 , respectively. The smear findings were compared with culture results to analyze specificity, sensitivity, and predictive values of the staining techniques. RESULTS: The sensitivity of Gram stain in the detection of bacteria was 36.0% in early and 40.9% in advanced @entity1036 cases; however, the specificity was higher in both groups (84.9% and 87.1%, respectively). Comparatively, the sensitivity and specificity of fungal detection were higher using @entity3071 +CFW in early (61.1% and 99.0%, respectively) as well as advanced @entity1036 (87.7% and 83.7%, respectively). Predictive values were high for @entity3071 +CFW in fungus detection, while they were poor for Gram stain in bacteria detection. In advanced @entity1036 cases, the false positives were @entity364 (16.3%) than in bacterial detection (10.3%), while the false negatives were significantly higher in bacterial detection compared with fungal detection (59.1% versus 12.3%, p< 0.0001). In @entity1036 , on the other hand, both false positives and false negatives for bacterial detection were significantly higher than fungal detection. CONCLUSIONS: Decisions can reliably be based on @entity3071 +CFW stain of corneal scrapings for initiation of antifungal therapy in @entity1036 . The results of Gram stain, on the other hand, have limited value in therapeutic decisions for @entity1036 . Therefore, the search for a better modality for early and efficient diagnosis of @entity1036 needs to continue.
