Linear Lesions of the Skin

Background

Linear lesions of the skin may be secondary to several disease processes.

GENETIC Incontinentia pigmenti

INFLAMMATORY Lichenoid contact or phytophoto- dermatitis
Lichenoid drug eruption
Lichen planus
Lichen planopilaris
Linear porokeratosis
Lichen striatus
Psoriasis
Lupus erythematosus
Inflammatory linear verrucous epidermal nevus

NEOPLASTIC Metastasis

PATHOGENESIS CHARACTERIZATION

Lines of Blaschko
In 1901, Alfred Blaschko presented, on the occasion of the 7th Congress of the German Dermatological Society held in Breslau, a system of “nevus lines”. In his words, “I have tried…to delineate, from the total collection of available cases, a system of lines on the surface of the body representing the typical pattern that the linear nevi follow.”

He analyzed 170 case reports that he had received from colleagues of all parts of Europe he delineated an archetype of lines as observed in many congenital and some acquired skin disorders

These may represent a clinical expression of a genetically programmed clone of altered cells, perhaps first expressed during embryogenesis

Pigmentary disorders
Nevus achromicus (including hypomelanosis of Ito)
Linear hyperpigmentation arranged in small bands
Linear hyperpigmentation arranged in broad bands (McCune-Albright syndrome)

Epithelial Nevi
Sebaceous nevus including Schimmelpennig syndrome
Nonorganoid epidermal nevus (epidermolytic or nonepidermolytic type) Inflammatory linear verrucous epidermal nevus

X-linked dominant skin disorders
X-linked dominant skin disorders
Incontinentia pigmenti
Focal dermal hypoplasia
X-linked dominant chondrodysplasia punctata
Oral-facial-digital syndrome type 1
MIDAS syndrome
CHILD syndrome

Acquired
Acquired skin disorders with a polygenic background
Lichen striatus
Linear lichen planus
Linear lupus erythematosus

The lines of Blaschko on the head and neck

Rudolf Happle, etal.

J Am Acad Dermatol 2001;44:612-5 Abstract quote

Background: The system of Blaschko's lines has been insufficiently documented on the head and neck.

Objective: The aim of the study was to elaborate this pattern in a comprehensive way.

Method: One hundred eighty-six figures showing skin lesions following Blaschko's lines on the head and neck were collected from literature and patient files, transposed into drawings, and subsequently categorized according to 3 standard perspectives. Transparent sheets were superimposed to delineate an archetypical pattern.

Results: The definite lines are presented in a frontal, lateral, and dorsal view. On the face they show an hourglass-like configuration converging on the nasal root. However, in several areas these lines intersect at an angle of almost 90°. On the scalp they form a spiral configuration.

Conclusion: The system of Blaschko's lines on the head and neck as elaborated by this study is more precise than previously published diagrams. Remarkably, this archetypical pattern shows definite crossing of lines.

Fitzpatrick's Dermatology in General Medicine. 5th Edition. McGraw-Hill. 1999.

Commonly Used Terms

Skin

Last Updated 4/8/2001

GENETIC	Incontinentia pigmenti
INFLAMMATORY	Lichenoid contact or phytophoto- dermatitis Lichenoid drug eruption Lichen planus Lichen planopilaris Linear porokeratosis Lichen striatus Psoriasis Lupus erythematosus Inflammatory linear verrucous epidermal nevus
NEOPLASTIC	Metastasis

PATHOGENESIS	CHARACTERIZATION
Lines of Blaschko	In 1901, Alfred Blaschko presented, on the occasion of the 7th Congress of the German Dermatological Society held in Breslau, a system of “nevus lines”. In his words, “I have tried…to delineate, from the total collection of available cases, a system of lines on the surface of the body representing the typical pattern that the linear nevi follow.” He analyzed 170 case reports that he had received from colleagues of all parts of Europe he delineated an archetype of lines as observed in many congenital and some acquired skin disorders These may represent a clinical expression of a genetically programmed clone of altered cells, perhaps first expressed during embryogenesis
Pigmentary disorders	Nevus achromicus (including hypomelanosis of Ito) Linear hyperpigmentation arranged in small bands Linear hyperpigmentation arranged in broad bands (McCune-Albright syndrome)
Epithelial Nevi	Sebaceous nevus including Schimmelpennig syndrome Nonorganoid epidermal nevus (epidermolytic or nonepidermolytic type) Inflammatory linear verrucous epidermal nevus
X-linked dominant skin disorders	X-linked dominant skin disorders Incontinentia pigmenti Focal dermal hypoplasia X-linked dominant chondrodysplasia punctata Oral-facial-digital syndrome type 1 MIDAS syndrome CHILD syndrome
Acquired	Acquired skin disorders with a polygenic background Lichen striatus Linear lichen planus Linear lupus erythematosus
The lines of Blaschko on the head and neck Rudolf Happle, etal.	J Am Acad Dermatol 2001;44:612-5 Abstract quote Background: The system of Blaschko's lines has been insufficiently documented on the head and neck. Objective: The aim of the study was to elaborate this pattern in a comprehensive way. Method: One hundred eighty-six figures showing skin lesions following Blaschko's lines on the head and neck were collected from literature and patient files, transposed into drawings, and subsequently categorized according to 3 standard perspectives. Transparent sheets were superimposed to delineate an archetypical pattern. Results: The definite lines are presented in a frontal, lateral, and dorsal view. On the face they show an hourglass-like configuration converging on the nasal root. However, in several areas these lines intersect at an angle of almost 90°. On the scalp they form a spiral configuration. Conclusion: The system of Blaschko's lines on the head and neck as elaborated by this study is more precise than previously published diagrams. Remarkably, this archetypical pattern shows definite crossing of lines.