Scraping cytology and scanning electron microscopy in diagnosis and therapy of corneal ulcer by mycobacterium infection

Abstract

Purpose: This work is aimed at demonstrating that scraping cytology and scanning electron microscopy can successfully assist in the diagnosis of nontuberculous mycobacteria infection. For this purpose, we report the use of both these techniques in the diagnosis of cornel ulcer in a previously healthy young man.

Methods: Cytological samples were achieved by scraping technique on the mucosa, both sub palpebral and temporal area of the eye tarsal conjunctiva. The obtained sample was affixed to a sanded rectangular slide, stained with the Pappenheim method, washed in bidistilled water, treated in Giemsa solution, washed again and subsequently dried on a hot plate and observed with a microscope at various magnifications.

Results: After a therapy based on a 500 mg clarithromycin tablet administered every 12 hours for 30 days as systemic therapy, a complete recovery of the patient from left eye inflammation was observed and SEM cytology showed that NTM colonies had disappeared.

Conclusion: Conjunctival cytology scraping and SEM technologies can be therefore exploited as new tools in diagnosis and fast identification of these newly discovered mycobacteria. In fact, they have a new way for studying ocular pathology, because of the simple execution and remarkable accuracy in the diagnosis. In fact, this technique allows to gather valuable information about all pathogens expression and the cellular action involved in pathology. As a further plus, this technique provides clinicians with the opportunity to repeat the SEM cytology for monitoring patients during therapy, hence leading to evaluate the efficacy of the pharmaceutical regimen in real time.