Image Description
Introduction: Diffuse cutaneous mastocytosis is the rarest variant of cutaneous mastocytosis (CM) and accounts for 1-2% of all cases of CM. It is seen almost exclusively in children. Most cases present during infancy, predominantly in the neonatal period. Two variants have been recognized: bullous type shows extreme blistering and pseudoxanthomatous type shows skin infiltrates.
Clinical Features: The patients present with generalized erythroderma and blister formation, usually on trunk, extremities, or scalp. The skin shows reddish-brown discoloration and becomes diffusely thickened with a leathery (peau chagrine) or pitted/dimpled (peau d'orange) appearance. Other features include: pruritus, positive Darier sign and dermatographism. Systemic symptoms caused by mediator release are more common in this condition than other forms of CM and include: flushing, hypotension, anaphylaxis, diarrhea and gastrointestinal bleeding.
Pseudoxanthomatous type grossly may have yellow-orange infiltrate in the dermis. The skin biopsy shows a band-like infiltrate of mast cells in papillary and reticular dermis. Histologically, it may be indistinguishable from mastocytoma. The immunohistochemical and molecular genetic features are similar to those described previously for other forms of cutaneous mastocytosis.
Clinical Features: The patients present with generalized erythroderma and blister formation, usually on trunk, extremities, or scalp. The skin shows reddish-brown discoloration and becomes diffusely thickened with a leathery (peau chagrine) or pitted/dimpled (peau d'orange) appearance. Other features include: pruritus, positive Darier sign and dermatographism. Systemic symptoms caused by mediator release are more common in this condition than other forms of CM and include: flushing, hypotension, anaphylaxis, diarrhea and gastrointestinal bleeding.
Pseudoxanthomatous type grossly may have yellow-orange infiltrate in the dermis. The skin biopsy shows a band-like infiltrate of mast cells in papillary and reticular dermis. Histologically, it may be indistinguishable from mastocytoma. The immunohistochemical and molecular genetic features are similar to those described previously for other forms of cutaneous mastocytosis.