By Gary M. White, MD
Trichomycosis. This most commonly occurs in the groin or axilla.
Pediculosis. Shown here in the pubic area.
Hair Follicle Nevus
Acquired Progressive Kinking Of Hair
Woolly Hair Nevus
Ectodermal Dysplasias: Alopecia of the eyebrows along with more generalized hypotrichosis, fragile hair, and other findings may occur in both hidrotic and hypohidrotic ectodermal dysplasia.
Hypotrichosis, Hair Structure Defects, Hypercysteine Hair And Glucosuria [BJD 1996;134;319].
Congenital hypotrichosis and Stargardt macular dystrophy characterized by hair loss, macular degeneration, and progressive loss of vision.
(An Bras Dermatol 88:jan/feb 2013)
Trichorhinophalangeal Syndrome Type I
See Green Hair
Scalp Hair Heterochromia in a 5-year-old child thought to represent somatic mosaicism [Peds Derm 2014;31;733]. The lighter hair was blond and not white as in poliosis.
Acquired Hypertrichosis Singularis
Median Nasal Dermoid Fistula
Yellowing of the hair is called xanthotrichosis. It may occur from a wide variety of factors including cigarette smoke, copper, picric acid, resorcinol (dihydroxybenzene), and topical medications e.g., anthralin, minoxidil, selenium sulfide and tar shampoo [Dermatology Online Journal 22;6].
Leukotrichia means white hair. The acute change of dark hairs to light in a localized area may occur in vitiligo, alopecia areata and during the regression of nevi e.g., halo nevi [Indian J Dermatol 2016;61:238].
Diffuse graying of the hair is called canities and usually occurs as a natural process of aging. Rapid whitening of the hair (e.g., overnight) is probably due to selective loss of only the pigmented hair in alopecia areata. Gradual premature graying may occur in progeria, Werner syndrome, dystrophia myotonica, Book syndrome (palmoplantar hyperhidrosis, premolar hypodontia), after beginning chloroquine, and cri-du-chat syndrome. The drug pazopanib turned one man's black hair nearly completely white over 5 months. [Ann Dermatol. 2015 Dec; 27(6): 791–792]
Premature Graying of Hair
Graying of hair may occur in unusual distributions, e.g., unilaterally. [Int J Trichol 2015;7:85-6]
Repigmentation of prematurely gray/white hair has been reported with various medications including latanoprost, lenalidomide, para-aminobenzoic acid, acitretin, etretinate, corticosteroids, cyclosporine, L-thyroxine, verapamil, tamoxifen, levodopa, cisplatin, erlotinib, adalimumab, and imatinib [Dermatology Online Journal 21;6].
Both lentigo maligna and melanoma may cause localized darkening of hair [JAMA Derm 2016;152;81].
Felting. For a picture, see Indian Dermatol Online J 2015;6:310-1
Uncombable Hair Syndrome
Porphyria Cutanea Tarda