REPORT OF A CASE
A 26-year-old blonde woman presented with a hair abnormality that had been present since infancy. On examination the hair was dry, 20 cm long, and showed alternating shiny and dull areas, giving the scalp hair a scintillating appearance (Figure 1). There was no increased fragility of the hair or other abnormality observed on the scalp examination. The axillary and pubic hairs were also affected. The findings of the rest of the physical examination were unremarkable. The patient stated that her mother and one of her brothers had similar hair changes. The light microscopic appearance of the hair shaft is shown in Figure 2 and Figure 3.What is your diagnosis?DIAGNOSIS: Pili annulati.Light microscopy revealed alternate light and dark bands of varying length along the hair shaft (Figure 2). A gasfilled cavity (a dark band) is shown at a greater magnification in Figure 3.
Amichai B, Grunwald MH, Halevy S. Hair Abnormality Present Since Childhood. Arch Dermatol. 1996;132(5):582. doi:10.1001/archderm.1996.03890290117018