Nontuberculous mycobacterial keratitis. Report of two cases and review of the literature.

We report two cases of nontuberculous mycobacterial keratitis. To our knowledge, case 1 is the first documented case of Mycobacterium chelonei sclerokeratitis and case 2 is the first report of Mycobacterium flavescens keratitis. A total of 40 cases of nontuberculous mycobacterial keratitis involving at least five different species have been reported previously in the literature. Almost all of these opportunistic infections have occurred following either accidental or surgical ocular trauma, usually associated with the use of local corticosteroids. Encountered infrequently, these organisms can be incorrectly identified as other bacteria, including diphtheroids and Nocardia species. Histopathologic examination and special stains of infected tissues may be helpful in establishing the correct diagnosis. Cultures and sensitivity testing are mandatory in determining appropriate treatment.