Intractable nontuberculous mycobacterial keratitis successfully treated by penetrating keratoplasty--3 cases report

Since the first diagnosis of nontuberculous mycobacterial keratitis in Taiwan on 1983 by Chen et al., we have collected another 70 cases. Although most of the cases were difficult to treat medically, almost all cases healed before optical penetrating keratoplasties were performed. But, three of these cases responded poorly to medical treatment with sporadical relapse. Finally, penetrating keratoplasties (PKP) were performed on these three cases. These three cases were all males, aged 48, 27, and 35 respectively. The durations from the onset to receiving PK were 10, 4, and 6 months. All had histories of corneal trauma and all cases responded poorly or inconsistently to topical amikacin, erythromycin and antituberculous drugs. Histopathological examination of the diseased corneas in the first chronic case showed granuloma formation in the area of ulcer base. The second case presented lymphocyte clustering in the subepithelial region. The third case, which was operated in a relatively inflamed stage, had lymphocytes infiltrating the whole layer of the cornea. The results of PKP in the three eyes were therapeutically and optically successful, though the second case failed in the first penetrating keratoplasty due to acute tissue failure without recurrent infection. The best corrected visual acuities in the three eyes, postoperatively, were 20/25, 20/40, and 20/100 respectively. With the successful experience of these three cases, we suggest that performing PKP for intractable nontuberculous mycobacterial keratitis at an early stage may reduce the duration of the patients' suffering.