Laboratory studies in chronic conjunctivitis.

Conjunctival cultures and scrapings for cytological examination were done in 852 cases of chronic conjunctivitis. Bacteria were recovered in 464. Of these, Staphylococcus sp were isolated in 91%; their etiologic importance over normal flora is questionable. Important cytological findings included atypical epithelium (three cases), Halberstaedter-Prowazek inclusion bodies (two), and eosinophils (104). Epithelial degenerative changes were common (585 cases). Crystals (105) and microorganisms (283) were other frequent findings. Active infection seems to be an uncommon cause of chronic conjunctivitis. Cultures are important in avoiding unnecessary antibiotic therapy when no organism is present. Cytological examination can be a helpful diagnostic adjunct in selected cases and is to be recommended especially in chronic follicular conjunctivitis, possible drug toxicity or allergy, dry eye states, and other atypical clinical presentations.