Skip to Main Content

++

Accumulation and degranulation of mast cells (mastocytosis) in the skin or other organs. A group of disorders characterized by accumulation of mast cells in the skin with or without other organ system involvement. Systemic mastocytosis occurs in approximately 10% of all cases, with proliferation of mast cells in other tissues such as bone, liver, and spleen.

++ ++ ++ ++
Mastocytosis
Graphic Jump Location

Severe form of diffuse cutaneous mastocytosis in an infant.

++
Mastocytosis
Graphic Jump Location

Thickening of the palms in an infant with diffuse cutaneous mastocytosis.

++
Mastocytosis
Graphic Jump Location

Multiple mastocytomas on the back of an adult man.

++

Mast Cell Disease; Systemic Mast Cell Disease (SMCD).

++

A classification of mastocytosis has been proposed based on clinical presentation and prognosis (see the WHO Classification of Mastocytosis in Table M-1).

++
Table Graphic Jump Location
Table M-1 WHO Classification of Mastocytosis
++

The cutaneous manifestation, urticaria pigmentosa, is the most common form and was first described in 1869.

++

Rare; approximately 1-4:10,000 live births.

++

Usually not considered an inherited disease, although there is some evidence of an autosomal dominant pattern in the diffuse cutaneous form. Males and females are affected equally.

++

There is an excess of mast cells in body tissues, and the clinical expression of the disorder depends upon the pattern of localization of the mast cells to specific organs. Dysregulation of production and function of mast cells is caused by distinct mutations in c-Kit, a type III transmembrane tyrosine kinase. Mediator release by mast cells may occur spontaneously or be triggered by a variety of stimuli. These biochemical substances include histamine and heparin, thought to be the most important, and other enzymes such as chymases, tryptases, and hydrolases. Prostaglandin D2, cytokines (tumor necrosis factor [TNF]-α and TNF-β, interleukin [IL]-3, IL-5, and IL-16), serotonin, leukotrienes, and platelet-activating factor are also released. Among the precipitating factors are trauma, surgery, extremes of temperature, toxins, alcohol, and a variety of drugs (including acetylsalicylic acid, morphine, codeine, thiopentone, lignocaine, gallamine, and d-tubocurarine).

++

History of recurrent flushes, urticarial wheals, pruritus, dizziness, and headaches. ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.