Becoming less common. Poikiloderma is a term used to describe a patch of skin with (1) reticulated hypo- and hyperpigmentation, (2) wrinkling secondary to epidermal atrophy, and (3) telangiectasias. Poikiloderma does not imply a single disease entity—although becoming less common, it is seen in skin damaged by ionizing radiation as well as in patients with autoimmune connective tissue diseases, primarily dermatomyositis (DM), and rare genodermatoses (., Kindler syndrome). In scleroderma, the dilated blood vessels have a unique configuration and are known as mat telangiectasias. The lesions are broad macules that usually measure 2–7 mm in diameter but occasionally are larger. Mats. | Chapter 054. Skin Manifestations of Internal Disease Part 8 Becoming less common. Poikiloderma is a term used to describe a patch of skin with 1 reticulated hypo- and hyperpigmentation 2 wrinkling secondary to epidermal atrophy and 3 telangiectasias. Poikiloderma does not imply a single disease entity although becoming less common it is seen in skin damaged by ionizing radiation as well as in patients with autoimmune connective tissue diseases primarily dermatomyositis DM and rare genodermatoses . Kindler syndrome . In scleroderma the dilated blood vessels have a unique configuration and are known as mat telangiectasias. The lesions are broad macules that usually measure 2-7 mm in diameter but occasionally are larger. Mats have a polygonal or oval shape and their erythematous color may be uniform or the result of delicate telangiectasias. The most common locations for mat telangiectasias are the face oral mucosa and hands peripheral sites that are prone to intermittent ischemia. The CREST calcinosis cutis Raynaud s phenomenon esophageal dysmotility sclerodactyly and telangiectasia variant of scleroderma Chap. 316 is associated with a chronic course and anticentromere antibodies. Mat telangiectasias are an important clue to the diagnosis of the CREST syndrome as well as systemic scleroderma for they may be the only cutaneous finding. Periungual telangiectasias are pathognomonic signs of the three major autoimmune connective tissue diseases lupus erythematosus scleroderma and DM. They are easily visualized by the naked eye and occur in at least two-thirds of these patients. In both DM and lupus there is associated nailfold erythema and in DM the erythema is often accompanied by ragged cuticles and fingertip tenderness. Under 10x magnification the blood vessels in the nailfolds of lupus patients are tortuous and resemble glomeruli whereas in scleroderma and DM there is a loss of capillary loops and those that remain are markedly dilated. In hereditary hemorrhagic .