Cutaneous collagenous vasculopathy with generalized telangiectasia: an immunohistochemical and ultrastructural study.

We report a 54-year-old male, with a 5-year history of spreading asymptomatic generalized cutaneous telangiectases. The patient had no mucosal or nail involvement, no positive family history and no clinical evidence of systemic disease or bleeding diathesis. Histologically, the superficial small dermal blood vessels were dilated and showed thickened walls with hyaline perivascular material, staining as collagen. The vessel walls were PAS and colloidal iron stain positive, and immuno-histochemically lacked actin staining. Collagen IV, fibronectin and laminin antibodies showed the material deposited around the basement membrane zone. Ultrastructurally, the vessels were post-capillary venules (PCV) and showed marked collagen deposition around the basal lamina. There were many abnormally banded widely spaced fibres with 100-150 nm periodicity (Luse bodies), in addition to regular banded collagen. Pericytes were sparse and lacked intracytoplasmic filaments, and few veil or fibroblastic cells were seen embedded within the collagen. We believe this is a form of cutaneous microangiopathy not previously described, with distinct morphology and unique ultrastructural features. It may be due to a genetic defect with erroneous production of disorganized collagen in the cutaneous microvasculature. Dermatologists and Dermatopathologists should be aware of this unusual cutaneous vasculopathy.