Malaty R, Beuerman R W, Pedroza L
LSU Eye Center, Louisiana State University School of Medicine, New Orleans 70112.
Int J Lepr Other Mycobact Dis. 1990 Sep;58(3):554-9.
Leprosy shows a higher percentage of ocular involvement than any other systemic infection. In humans, the cornea is the first ocular tissue affected. Our previous studies in armadillos with naturally acquired and experimental disseminated leprosy showed that 44% had corneal infection. Mycobacterium leprae is found in armadillo burrows in Louisiana, U.S.A., and ocular abrasions may be the portal of entry for these organisms in wild armadillos. To test the cornea as a route of infection, we injected eight armadillos intrastromally with 2 x 10(6) M. leprae in 1 microliters. Two and 4 months later, the armadillos were sacrificed and their eyes processed for light- and electron-microscopy. After 2 months, M. leprae were found in histiocytes mainly in the corneal limbus, sclera and bulbar conjunctiva. At 4 months, however, there was a visible corneal leproma in one animal. Microscopically, it was found to be a histiocytic granuloma with heavy M. leprae invasion. In addition, cells were seen in the anterior chamber. Leprosy is endemic in regions where other corneal infections which compromise the epithelial barrier property are prevalent and where leprosy bacilli are found in the environment. The entry of leprosy bacilli into the cornea may produce lesions which spread posteriorly in the eye.
麻风病眼部受累的比例高于任何其他全身性感染。在人类中，角膜是首个受影响的眼部组织。我们之前对自然感染和实验性播散性麻风病犰狳的研究表明，44%的犰狳有角膜感染。在美国路易斯安那州的犰狳洞穴中发现了麻风分枝杆菌，眼部擦伤可能是这些微生物进入野生犰狳的门户。为了测试角膜作为感染途径，我们向8只犰狳的角膜基质内注射了1微升含2×10(6)个麻风分枝杆菌的菌液。2个月和4个月后，处死犰狳并对其眼睛进行光镜和电镜检查。2个月后，主要在角膜缘、巩膜和球结膜的组织细胞中发现了麻风分枝杆菌。然而，4个月时，有一只动物出现了明显的角膜瘤。显微镜下，发现它是一个组织细胞性肉芽肿，有大量麻风分枝杆菌浸润。此外，在前房中可见细胞。在其他损害上皮屏障特性的角膜感染流行且环境中存在麻风杆菌的地区，麻风病呈地方性流行。麻风杆菌进入角膜可能产生病变，并在眼内向后扩散。
