Hyaline Angiopathies

Hyalinization of the walls of cutaneous vessels in seen in a variety of disorders and is common in the collagen-vascular diseases (S8C24VA6-6).

In lesions of discoid lupus erythematosus, vessels in the papillary dermis and in the upper portion of the reticular dermis often have thickened, hyalinized walls (S8C30P16-1-3). These vascular changes are associated with a thickened basement membrane at the dermal-epidermal interface  and along the hair follicles.

In lesions of lupus profundus, vessels of the subcutaneous fat commonly have thickened, hyalinized walls (S8C31P17-1-5). Lymphocytes and histiocytes commonly infiltrate the walls and the sub-endothelial space of the affected vessels (lymphohistiocytic vasculitis).

Vessels, in the papillary dermis of acral skin in lesions of porphyria cutanea tarda, often are thickened and hyalinized. The walls of the affected vessels are PAS + (S8C30P16-4-5); these vascular changes may be associated with a thickened (PAS+) basement membrane at the dermal-epidermal interface. In the membrane and in the vascular hyaline deposits, immunoglobulins and complement are deposited.

Distinctive vascular and perivascular deposits of hyalin are the distinguishing feature of skin lesions in erythropoietic protoporphyria and lipoid proteinosis (S8C32P18-1-8). The perivascular deposits tend to be laminated.

Moy LS, et al: Lipoid proteinosis: ultrastructural and biochemical studies. J Am Acad Dermatol 1987;16:1193-1201.

Vascular lesions may be a feature of lesions of scleroderma. In the viscera, muscular vessels show fibrosis and hyalinization (S8C33P19-1). Hyalinization may also be a feature of the dermal lesions of scleroderma (S8C33P19-2).

Laminated hyaline deposits are a feature of lesions of granuloma faciale and erythema elevatum diutinum.