Mastocytosis

Abstract

It is known that patients with mastocytosis have an increased risk of anaphylaxis. This also appears to be the case with patients with evidence of a clonal mast cell disorder resulting in the monoclonal mast cell activation syndrome (MMAS) who do not express the full mastocytosis phenotype. Most patients with mastocytosis are recognized by their characteristic skin lesions. An increased level of baseline serum mast cell tryptase is also an indicator for a possible clonal mast cell disorder including mastocytosis. Other markers for mast cell clonality and for mastocytosis include abnormal immunostaining of mast cells with CD25 and CD2, clustering of mast cells in tissues, abnormal mast cell morphology, and the presence of a mutation in the proto-oncogene c-kit encoding for the mast cell growth receptor KIT. As recognition depends on an understanding of mastocytosis, and this disease should be considered in patients with recurrent anaphylaxis, we describe the features of mast cell clonality, MMAS and mastocytosis; and review recent findings.

Proposed diagnostic algorithm for patients with suspected mastocytosis: a proposal of the European Competence Network on Mastocytosis

“…Some of these patients suffer from an IgE-dependent allergy (18)(19)(20)(21)(22)(23)(24)(25). The symptoms recorded may be mild, but can also be severe or even life-threatening (18)(19)(20)(21)(22)(23)(24)(25).…”

“…Some of these patients suffer from an IgE-dependent allergy (18)(19)(20)(21)(22)(23)(24)(25). The symptoms recorded may be mild, but can also be severe or even life-threatening (18)(19)(20)(21)(22)(23)(24)(25). Various organ systems, including the skin (pruritus and flushing), the gastrointestinal tract (peptic symptoms, cramping and diarrhoea) and the central nervous system (headache, depression, moods and cognitive symptoms), may be involved (1)(2)(3)(4)(5)(6)(7)(8)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27).…”

“…The symptoms recorded may be mild, but can also be severe or even life-threatening (18)(19)(20)(21)(22)(23)(24)(25). Various organ systems, including the skin (pruritus and flushing), the gastrointestinal tract (peptic symptoms, cramping and diarrhoea) and the central nervous system (headache, depression, moods and cognitive symptoms), may be involved (1)(2)(3)(4)(5)(6)(7)(8)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27). In a smaller group of these patients, a mast cell activation syndrome (MCAS) is recorded (18)(19)(20)(21)(22)(23)(24)28).…”

“…Various organ systems, including the skin (pruritus and flushing), the gastrointestinal tract (peptic symptoms, cramping and diarrhoea) and the central nervous system (headache, depression, moods and cognitive symptoms), may be involved (1)(2)(3)(4)(5)(6)(7)(8)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27). In a smaller group of these patients, a mast cell activation syndrome (MCAS) is recorded (18)(19)(20)(21)(22)(23)(24)28). Finally, patients with SM may also suffer from osteopenia or osteoporosis (sometimes with bone fractures) and from the cosmetic consequences of the disease (18,26,29) (Table 1).…”

IL-33/ST2 axis promotes mast cell survival via BCLXL

“…The single most important mediator in this process is stem cell factor (SCF), a master regulator of MC proliferation, differentiation, survival, and activation. Mice with genetic mutations affecting SCF or its receptor Kit have few or no MC in healthy or inflamed tissues, whereas activating mutations of Kit give rise to pathologic mastocytosis (13)(14)(15). IL-3 is another well-recognized MC growth factor (16).…”