Chronic alcoholism and microbial keratitis.

In a series of 227 consecutive, non-referred patients with microbial keratitis an analysis of the accumulated hospital records showed that one-third were associated with chronic alcoholism. The diagnosis of alcoholism was usually unsuspected on admission to hospital. The microbial pathogenesis in these patients was distinctive; coagulase-negative staphylococci, alpha- and beta-streptococci, moraxellae, enteric Gram-negative bacilli, and polymicrobial infections were unusually prominent. Pseudomonas aeruginosa was uncommon. Trauma, exposure, bullous keratopathy, other external ocular diseases, and self-neglect were the major recognised predisposing causes. The nutritional, toxic and immunological sequelae of alcoholism may also have been contributory. Ophthalmologists should be alert to the diagnosis of chronic alcoholism in their patients. Chronic alcoholism may be an important and underrated risk factor for microbial keratitis.