Clinical Course and Histopathological Findings of the Patients with Melanosis

Eighteen cases with melanosis including melanosis faciei feminea and melanodermitis toxica whose causative agents were identified by clinical course and patch testing and whose histological examination showed incontience of pigment were selected to study the correlations between causative agents and histopathological findings. These cases were histopathologically divided into three groups, and there were definite correlations between the causative agents and histopathological findings. First group, melanosis of allergic lichenoid type whose causative agents were identified such as Sudan I and naphtol-AS showed extensive liquefaction degeneration of the basal layer and namely basal mottled degeneration which means the mottled pattern of degeneration of the basal cells and basement membrane. The second group, melanosis of allergic non-lichenoid type whose causative agents were identified such as jasmin oil, captan and folmaldehyde showed focal liquefaction degeneration of the basal layer. The last group, melanosis of chronic irritant type whose causative agents were identified such as kerosene and gasoline showed acanthosis and hyperpigmentation of the basal layer.