Mastocytosis Clinical Presentation

Updated: Sep 16, 2020
  • Author: Jacquiline Habashy, DO, MSc; Chief Editor: Dirk M Elston, MD  more...
  • Print


Mastocytosis patients may present with cutaneous lesions, systemic symptoms of an acute nature, and/or chronic systemic symptoms.

Most patients have pruritic cutaneous lesions. Some patients, especially those with extensive cutaneous disease, experience acute systemic symptoms exacerbated by certain activities or ingestion of certain drugs or foods. Possible systemic symptoms include flushing, headache, dyspnea, wheezing, rhinorrhea, nausea, vomiting, diarrhea, and syncope.

Patients also may have chronic systemic symptoms involving various organ systems. Involvement of the skeletal system may be manifested as bone pain or the new onset of a fracture. Long-term exposure to heparin and stem cell factor from degranulated mast cells is believed to put patients at risk for osteoporosis. [31]  Involvement of the central nervous system may produce neuropsychiatric symptoms, as well as nonspecific changes such as malaise and irritability. GI involvement may yield weight loss, diarrhea, nausea/vomiting, and abdominal cramps. Cardiovascular effects can include shock, syncope (resulting from vascular dilatation), or angina. Anaphylactic reactions to hymenoptera stings may be the first sign of mastocytosis. [32]


Physical Examination

The most common physical findings in mastocytosis involve the skin, liver, spleen, and cardiovascular system.

Skin lesion types are as follows:

  • Macules, papules, nodules, and plaques (see image below)

    Lesion on the arm. Courtesy of Lee H. Grafton, MD. Lesion on the arm. Courtesy of Lee H. Grafton, MD.
  • Blisters and bullae in children (see image below)

    Blistering lesion. Blistering lesion.
  • Diffuse induration

  • Isolated nodule or tumor

Skin distribution findings are as follows:

  • Widespread symmetric distribution

  • Trunk involved more than extremities

  • Tendency to spare the face, scalp, palms, and soles; however, a patient with scarring alopecia has been reported [33]

Skin lesion color, quantity, and size findings are as follows:

  • Yellow-tan to red-brown

  • From 1 to more than 1000

  • From 1 mm to several centimeters

Skin special characteristics are as follows:

  • Darier sign: Wheal and surrounding erythema develop in a lesion after rubbing it.

  • Dermatographism: In approximately half the patients, stroking macroscopically uninvolved skin produces dermographia.

  • Flushing: Flushing may occur spontaneously following skin stroke or after ingesting a mast cell degranulating agent.

  • Diffuse cutaneous mastocytosis (DCM): This is rare and is characterized by mast cell infiltration of the entire skin.

  • Other: Large hemorrhagic bullous and infiltrative small vesicular variants occur. Blistering predominates in infancy, whereas grain-leather appearance of the skin and pseudoxanthomatous presentation develop with time. Anaphylactic shock may occur.

Liver findings include possible hepatomegaly, which is present in 40% of adult patients with systemic mastocytosis.

Spleen findings include possible splenomegaly, which is present in 50% of patients with systemic mastocytosis.

Cardiovascular findings include hypotension and tachycardia.

Gastrointestinal findings include abdominal pain, diarrhea, vomiting, and weight loss (frequency of involvement currently uncharacterized in patients with systemic mastocytosis). [34]



Complications may include the following:

  • Possible transformation into a hematologic malignancy

  • Death secondary to mast cell degranulation

  • Mast cell leukemia