Leprosy in wild armadillos (Dasypus novemcinctus) on the Texas Gulf Coast. Ultrastructure of the liver and spleen.

Recent studies have established that the "naturally-occurring leprosy-like disease of wild armadillos" is, indeed, caused by Mycobacterium leprae indistinguishable from M. leprae from human lepromatous leprosy. The present study reports the ultrastructure of the mycobacteria and host response in deep viscera, liver and spleen, in Texas armadillos with sylvatic leprosy. Evidence for acid-fast bacillary proliferation in these organs and penetration of hepatocytes is given. Acid-fast bacilli concentrated in activated macrophages in Billroth cords and sheaths of Schweigger-Seidel of the spleen and in Kupffer cells of the liver. Both mycobacteria and host response seen in lepromata of sylvatic leprosy, lepromatous lesions produced by injection of inocula from human lepromata and human lepromata, are compared.