The influx of extra sodium ions triggers prolonged muscle contractions, which are the hallmark of myotonia.Potassium-aggravated myotonia is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In some cases, an affected person inherits a mutation in the SCN4A gene from one affected parent. Other cases result from new mutations in the gene. These cases occur in people with no history of the disorder in their family. References


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Stiff skin syndrome (also known as "Congenital fascial dystrophy") is a cutaneous condition characterized by ‘rock hard’ induration, thickening of the skin and subcutaneous tissues, limited joint mobility, and mild hypertrichosis in infancy or early childhood. Immunologic abnormalities or vascular hyperactivity are not present in patients.Not much is known about it, cause or treatment, and further investigation is required, as it has only been reported 41 times throughout history. Genetics
This condition is associated with mutations in the Fibrillin 1 (FBN1) gene. Diagnosis
Differential diagnosis
Other conditions associated with mutations in this gene include acromicric dysplasia, Marfan syndrome and its variant Marfanoid–progeroid–lipodystrophy syndrome, autosomal dominant Weill-Marchesani syndrome, isolated ectopia lentis, MASS phenotype, and Shprintzen-Goldberg syndrome. See also
Scleroderma
Self-healing papular mucinosis
List of cutaneous conditions

References


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