Twisted collagen fibrils in acrocyanosis.

Essential acrocyanosis (EA) present as a dusky discoloration of the hands as the sole symptom without any other abnormal results from laboratory investigation. Previously, the authors have found twisted collagen fibrils (TCF) in the normal skin of an EA patient. This study was intended to evaluate the significance of TCF in EA. Thirteen patients showing dusky discoloration were randomly selected and studied for TCF in normal skin by routine electron microscopy. TCF were found in 10 of 13 patients; 3 patients with only the discoloration (EA), 3 with the mild symptoms which were supposed to be Ehlers-Danlos syndrome (EDS), 1 with definite symptoms of EDS, 1 with Raynaud's disease and 2 with hyperglobulinemia. TCF were the ultrastructural sign for inherited malformation of collagen fibrils. EA was probably elucidated as a vascular disorder in TCF-carrying people. EA could be included in the disease category of EDS but it seems unreasonable to force EA patients into one of the subtypes of EDS. For pathogenesis, the inherited dysfunction in the hypertrophic pericytes of the subpapillary vascular plexus was presumed.