Case Report and Study of Collagen Metabolism in Ehlers‐Danlos Syndrome Type II

A case report on a 41‐year‐old Japanese woman with prominent features of Ehlers‐Danlos syndrome is presented. At birth, the patient was noted to have moderate hyperlastic skin and hypermobility of the joints, especially those of the hands and fingers. She bruised easily, formed purpura, and had cigarette paper scars. From the age of 38, she became aware of palpitation, dyspnea and easy fatigue on exertion; examination showed mitral insufficiency. Mitral‐valve prolapse was revealed by echocardiogram and CT echogram. Upper G‐I series of X‐ray revealed duodenum diverticula. At the age of 42, she was operated for mitral valve replacement. From the clinical features she was dignosed as having Ehlers‐Danlos syndrome type II. Tissue sections stained with H‐E showed a few, fine, disorderly arranged collagen fibers. Electron microscopically, the diameter of individual collagen fibrils was rather more varied than that in normal skin, but the average diameter was within the normal range. In longitudinal sections, no apparent abnormal findings could be observed. Cultured dermal fibroblasts from the patient synthesized pro alpha 1 trimer of type I collagen but failed to secrete type III procollagen or pro alpha 2 chain of type I collagen. Affected cells were stained with antibodies against type I and type III collagen. Specific fluorescences against type I collagen were observed and very faint positive results against type III collagen were seen. These studies indicate that secreted altered type I procollagens that are synthesized can result in the clinical syndrome of our case.