GIANT AXONAL DEGENERATION - SCANNING ELECTRON-MICROSCOPIC AND BIOCHEMICAL-STUDY OF SCALP HAIR

Tightly curled 'frizzy' hair is a pathognomonic sign of giant axonal d egeneration (GAD). The present study compares the morphological struct ure of the scalp hair of a GAD patient with that of her parents and fi rst-degree relatives with the aid of scanning electron microscopy. The comparison included plaited hair of two age-matched controls, in orde r to exclude mechanical plaiting artifacts. Trichorrhexis nodosa and f ringing of the cut ends were exclusively found in the patient's hair. Longitudinal grooving was also frequently seen in hair of normal perso ns. Assay of carbon (C), sulfur (S) and nitrogen (N) contents of the p atient's hair was normal, but the S:N ratio was significantly reduced, as compared with her relatives. However, comparison with a control gr oup of nonrelated healthy volunteers showed no difference.