Hair casts.

A case of hair casts in an 8-year-old girl is described. The disorder is rare, the first description dating back to 1897 with a total of only 31 cases reported in the literature since then. The results of research conducted using the optic and electron microscopes (transmission and scanning) are recorded. These studies show that the typical lesion consists of two concentric layers of keratinized cells of differing structure: one resembling the inner layer of Huxley's sheath and the outer layer resembling Henle's layer.