58. Mastocytosis
Definition
Mastocytosis is a clonal disorder in which mast cells and the precursor cells accumulate in different tissues, such as bone marrow, skin, gastrointestinal tract, liver, and spleen.
Classifications of Mastocytosis
| Category IA | Indolent disease with skin involvement |
| Category IB | Systemic involvement with or without skin involvement |
| Category II | A hematopoietic disorder is a part of the disease |
| Category IIA | Dysmyelopoietic disorder associated with mastocytosis |
| Category IIB | Accompanied by myeloproliferative disease |
| Category IIC | Associated with nonlymphocytic leukemia |
| Category IID | Associated with malignant lymphoma |
| Category IIE | Associated with neutropenia |
| Category III | Mast cell leukemia becomes a part of the disease |
| Category IV | Associated with lymphadenopathic mastocytosis with eosinophilia (also known as aggressive mastocytosis) |
Incidence
The incidence of mastocytosis is extremely rare. The specific frequency of occurrence has not been documented.
Etiology
Mutations of the c- kit proto-oncogene have been implicated as the cause of some forms of mastocytosis. The systemic form, a codon-816 c- kit mutation, is commonly found.
Signs and Symptoms
• Abdominal pain
• Anemia
• Ascites
• Basophilia
• Budd-Chiari syndrome (see p. 59)
• Dilated small bowel
• Diverticulitis
• Eosinophilia
• Esophageal stricture
• Esophageal varices
• Esophagitis
• Hepatomegaly
• Leukocytosis
• Leukopenia
• Lymphadenopathy
• Lymphopenia
• Malabsorption
• Monocytosis
