BLASCHKO’S LINES

http://www.aocd.org

The lines of Blaschko are a pattern of lines on the skin that represent the developmental growth pattern during epidermal cell migration. The lines are distinguished from other morphological lines of the skin and do not represent vascular, lymphatic or nervous structures. Typically these lines are not visible; however, certain inherited and acquired diseases of the skin follow Blaschko’s lines. Blaschko’s lines were originally described by Dr. Alfred Blaschko in 1901 when he examined over 140 patients with linear skin lesions that followed similar patterns. A diagram of the distribution pattern of these lines has since been drawn and is now referred to as the lines of Blaschko. Blaschko’s lines follow a V-shape over the upper spine, an S-shape over the abdomen, an inverted U-shape from the breast to the upper arm, and perpendicular lines up and down the arms and legs. They also appear on the head and neck in a less well-defined manner. The following congenital, acquired and genetic diseases follow Blaschko’s lines:

Congenital Skin Disorders Acquired Skin Disorders (continued)  Bart syndrome  Linear psoriasis  Epidermal Nevus  Linear scleroderma  Hypomelanosis of Ito  Lichen striatus  Inflammatory linear verrucous epidermal nevus  Lupus erythematosus  Linear and whorled nevoid hypermelanosis  Segmental vitiligo  Linear basal cell nevus  Linear Darier’s disease Genetic Skin Disorders  Linear eccrine nevi  CHILD syndrome  Linear epidermolytic hyperkeratosis  Conradi-Hunermann syndrome  Linear nevus comedonicus  Familial cutaneous amyloidosis, Partington type  Linear porokeratosis of Mibelli  Focal dermal hypoplasia  Nevus corniculatus  Incontinentia pigmentii  Nevus depigmentosus  Melanotic macules of McCune-Albright syndrome  Nevus sebaceous of Jadassohn  Menke’s syndrome  Relapsing linear acantholytic dermatosis  Oro-facial-digital syndrome, type I  Syringocystadenoma papilliferum  Segmental ash leaf spot  Unilateral nevoid basal cell carcinoma syndrome  X-linked hypohidrotic ectodermal dysplasia Acquired Skin Disorders  Extragenital lichen sclerosus  Generalized lichenoid drug eruption  Lichen striatus  Linear atrophoderma of Moulin  Linear fixed drug eruption  Linear lichen planus  Linear mucinoses and mycosis fungoides

This information has been provided to you compliments of the American Osteopathic College of Dermatology and your physician.

The medical information provided in this article is for educational purposes only and is the property of the American Osteopathic College of Dermatology. It is not intended nor implied to be a substitute for professional medical advice and shall not create a physician - patient relationship. If you have a specific question or concern about a skin lesion or disease, please consult a dermatologist. Any use, re-creation, dissemination, forwarding or copying of this information is strictly prohibited unless expressed written permission is given by the American Osteopathic College of Dermatology. For detailed information including links to related topics on this and many other skin conditions with photos, visit: https://www.aocd.org/page/DiseaseDatabaseHome