Progressive capillary hemangioma

Progressive capillary hemangioma is a vascular disease characterized by proliferation of endothelial cells within dilated capillaries. The etiology is unclear, first reported by Hutchinson in 1889. It predominantly affects females, with onset usually before the age of 16. Typical lesions are small, red to purplish vascular nodules or papules, approximately 1mm in diameter, slightly raised on the skin surface, blanching upon pressure, and tend to occur in clusters with a creeping pattern of development. As the condition progresses, the original lesions regress and flatten, while new lesions appear around them, presenting a ring-shaped or reticular lace-like appearance with scales and mild lichenification, accompanied by superficial brownish discoloration and pigment deposition, usually asymptomatic. Lesions can occur anywhere on the body except palms, soles, and mucous membranes, with lower limbs being the most common site.

Pathological Features

The most important histological manifestation of progressive capillary hemangioma is the expansion and tortuosity of capillaries in the papillary dermis and upper dermis, with thickened walls and proliferative endothelial cells. Inflammatory changes, mainly lymphocytic infiltration, may be observed around the vessels. There is no hemorrhage or hemosiderin deposition. Dilated capillaries do not exhibit alkaline phosphatase activity, distinguishing them from normal capillaries.

Diagnosis and Differential Diagnosis

Diagnosis is usually straightforward based on clinical and histopathological findings, although differentiation from Schamberg's progressive pigmentary dermatosis is necessary. The latter tends to have pepper-like spots that merge to form diffuse pigmentary patches. Capillaritis with a ring-shaped purpura is bilateral and characterized by acute, episodic capillary dilation points that expand peripherally to form small rings. In Gougerot and Blum's lichenoid purpura pigmentary dermatosis, primary lesions are tiny, lichenoid, reddish-brown papules, sometimes hemorrhagic, with central regression leaving behind pigmentary changes.

Treatment

The course of progressive capillary hemangioma is slow, with lesions regressing and recurring, but they generally do not completely disappear. Treatment with pulsed dye laser therapy in clinical practice can improve or alleviate these lesions.

Source: Progressive capillary hemangioma