<unk>  is a rare and heterogeneous disease characterized by the presence of excessive numbers of mast<unk> s in various organs, mainly the skin and the bone marrow that manifests with an unusually broad spectrum of clinical and morphological appearances. Based on the affected organ(s),<unk>  may be classified into either cutaneous mastocytosis or systemic mastocytosis.<unk>  may be classified into seven subtypes based on WHO classification system. Cutaneous mastocytosis is more common in children and the disease manifest itself in the first year of life in over 80% of cases. There is no sex predilection and race predilection to the<unk> .<unk>  arises from the mast<unk> , which is a type of white blood<unk>  involved in the inflammatory process. The progression to<unk>  usually involves the uncontrolled stimulation of the receptor for stem<unk>  factor following mutation of C-kit<unk>  surface receptor. On microscopic histopathological analysis, mast<unk> s in the superficial and mid dermis that are lymphocyte like with dense granular cytoplasm which tend to be more abundant around blood vessels is characteristic finding of<unk> .<unk>  must be differentiated from other diseases that cause flushing,such as: phaeochromocytoma and carcinoid syndrome.<unk>  must be differentiated from other diseases that cause elevated serum tryptase levels and cytopenia, such as: myelodysplastic syndrome, primary myelofibrosis, essential thrombocythemia, and chronic eosinophilic leukemia. Common complications of<unk>  include episodes of anaphylaxis, osteoporosis, and progression to malignant mastocytosis or mast<unk>  leukemia. The prognosis of<unk>  varies with the subtype, location, and extent of the<unk> . The cutaneous mastocytosis is associated with the most favorable prognosis and mast<unk>  leukemia is associated with poor prognosis. The diagnosis of systemic mastocytosis is based on the presence of one major criterion and one minor criterion or three minor criteria. Major criteria include the presence of multifocal dense infiltrates of mast<unk> s observed in bone marrow sections or other extra cutaneous organs. Four minor criteria include the presence of >25% abnormal spindle-shaped mast<unk> s in bone marrow and/or tissues, detection of Kit mutation at codon 816 in bone marrow or extracutaneous organ(s), the expression of CD2 and
CD25 surface markers in C-kit positive mast<unk> s from bone marrow or other organs, and elevated serum tryptase levels >20 ng/mL. Physical examination for<unk>  include inspection for a large assortment of types of skin lesions, testing for dermatographism (Darier's sign), and palpating for hepatosplenomegaly and lymphadenopathy. Laboratory tests that may be helpful for diagnosis of<unk>  include complete blood count, serum tryptase levels, plasma and urinary histamine levels, and coagulation profile. Biopsy of affected organ may be performed to detect possible accumulation of mast<unk> s in an involved tissue. Other imaging studies for evaluation of<unk>  include sonography of internal organs, gastroscopy and colonoscopy with biopsy, and DXA scan of bones. The mainstay of therapy for<unk>  is avoidance of triggering factors and symptomatic therapy. Chemotherapy is indicated for aggressive form of<unk> .
Mast cell tumor
Solitary mastocytoma
Faisalabad histiocytosis
Thymic carcinoma
Langerhans cell histiocytosis
Malignant fibrous histiocytoma
Malignant histiocytosis
Mycetoma