Mixed Connective Tissue Disease (MCTD)

Changes of nailfold capillary patterns have been described in certain patients with systemic sclerosis, dermatomyositis, mixed connective tissue disease, and Raynaud’s syndrome. These changes are characterized by loss of (drop-out) nailfold capillary loops that surround the remaining, enlarged dilated capillaries. Upper left, A normal nailfold capillary pattern shows the uniform morphology and homogeneous distribution of the small capillary loops just below the cuticle. Upper right, Capillaroscopy in a patient with systemic sclerosis illustrates dilation of isolated capillary loops, with loss of surrounding loop structures. Lower right, The abnormal pattern is from a patient with childhood dermatomyositis. Dilated capillary loops are present, as well as areas of arborized clusters of capillary loops. This patient also has cuticular overgrowth. Lower left, Distortion of the normal capillary loop architecture is seen in a patient with adult dermatomyositis. Note the loss of normal homogeneous distribution of the capillaries and the alterations in the morphology of the vessels, including the dilated and enlarged “giant” capillary loops.