Cytology of Conjunctival inflammatory lesions

Allergic and vernal conjunctivitis are characterized by a prevalence of eosinophils in the inflammatory infiltrate. Bacterial and viral infections are generally diagnosed on the basis of clinical presentation or sometimes by microbiology. Nonetheless, cytological features may be helpful for a presumptive diagnosis, mainly in clinically unexpected cases, and in the general management of the patients. Infections by verruca vulgaris, measles, herpes may be suggested by specific cytological features. Trachoma is a “historical” bacterial conjunctival infection caused by Chlamydia trachomatis. The cytological features are almost the same as those described in the female genital tract and are characterized by cytoplasmic basophilic inclusions with halos. Cytological features of Candida, Aspergillus, mucormycosis conjunctivitis have also been described; diagnosis and treatment must be timely and effective because of the risk of corneal damage.