Type IX Ehlers-Danlos syndrome. A new variant with pathognomonic radiographic features.

The authors describe 7 male patients from two unrelated families who presented with what appears to be a heretofore undiagnosed X-linked variant of Ehlers-Danlos syndrome. Unlike the eight previously reported types, this variant is manifested by specific skeletal abnormalities, including occipital exostoses, widening and bowing of multiple long bones at tendinous and ligamentous insertion sites, and deformed clavicles. Major clinical complications include genitourinary problems, chronic diarrhea with malabsorption, and/or syncopal episodes. Laboratory tests suggest that this variant may represent the true lysyl-oxidase-deficient form of Ehlers-Danlos syndrome.