Cutaneous signs.

Cutaneous signs play a significant role in clinical medicine. Signs have often been named after the initial observer. They may indicate either dermatologic or systemic illness and aid the examiner in diagnosis and relevant investigations. Some are specific, some have been described in other conditions, and few have lost their relevance. Most of the signs are related to the pathogenesis of the disease but the cause of some is not clear.

Linear angioma serpiginosum.

Angioma serpiginosum distributed in a linear fashion along the upper extremity of an adolescent boy is described. Histopathologic examination revealed the characteristic numerous thick-walled capillaries in the dermal papillae.

Loss of kindlin-1, a human homolog of the Caenorhabditis elegans actin-extracellular-matrix linker protein UNC-112, causes Kindler syndrome.

Kindler syndrome is an autosomal recessive disorder characterized by neonatal blistering, sun sensitivity, atrophy, abnormal pigmentation, and fragility of the skin. Linkage and homozygosity analysis in an isolated Panamanian cohort and in additional inbred families mapped the gene to 20p12.3. Loss-of-function mutations were identified in the FLJ20116 gene (renamed "KIND1" [encoding kindlin-1]). Kindlin-1 is a human homolog of the Caenorhabditis elegans protein UNC-112, a membrane-associated structural/signaling protein that has been implicated in linking the actin cytoskeleton to the extracellular matrix (ECM). Thus, Kindler syndrome is, to our knowledge, the first skin fragility disorder caused by a defect in actin-ECM linkage, rather than keratin-ECM linkage.