TLDR The hair defect is due to abnormal inner root sheath keratinization.
A 4-year-old Caucasian girl with pili trianguli et canaliculi exhibited unique ultrastructural changes, including tonofilament-desmosomal detachment and tonofilament clumping within inner root sheath cells. These findings suggested that the hair anomaly in this condition might be due to a compromised cytoskeleton, leading to configurational changes in the inner root sheath. Despite these changes, keratinization of the inner root sheath still occurred, which typically precedes the keratinization of the hair shaft. Therefore, the abnormally configured inner root sheath influenced the surface characteristics of the hair shaft in pili trianguli et canaliculi.
6 citations,
August 1993 in “Archives of Dermatology” A woman's hair changed to a dry, tangled texture that's hard to comb after treatment with spironolactone, suggesting the medication might cause such hair changes.
26 citations,
September 1990 in “Ophthalmology” The study found no common cause for a girl's crystalline cataract and uncombable hair, suggesting their co-occurrence might be coincidental.
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12 citations,
November 1987 in “Pediatric dermatology” Four children had unmanageable pale blond hair due to uncombable-hair syndrome.
8 citations,
May 2005 in “The American journal of dermatopathology/American journal of dermatopathology” The hair defect is due to abnormal inner root sheath keratinization.
94 citations,
February 1994 in “The journal of investigative dermatology/Journal of investigative dermatology” EGF makes hair follicles grow longer but stops hair production.
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