"Relatively spared zones" in leprosy: a clinicopathological study of 500 patients.

In this study, clinically all forms of lesions like macules, plaques, and nodules were found in all the "relatively spared zones," except groins. Histopathology confirmed that the disease process was established and the acid-fast bacilli were not present as a part of bacteremic settlement. Hence, it appears that practically no area on the surface of skin is immune to invasion by M. leprae. However, as the incidence of lesions and AFB in these regions is relatively less, especially over axilla and groin, these areas can be considered as relatively spared zones but not completely resistant to development of lesions of leprosy.