II. Definitions

  1. Mastocytosis
    1. Abnormal proliferation and accumulation of Mast Cells within various organ systems
    2. May be limited to skin Mast Cell accumulation (Cutaneous Mastocytosis)
    3. May be diffusely increased in Bone Marrow, Spleen, and liver (Systemic Mastocytosis)

III. Pathophysiology

  1. Abnormal proliferation and accumulation of Mast Cells within various organ systems
  2. High number of Mast Cells degranulate, releasing vasoactive agents (esp. Histamine)

IV. Types

  1. Cutaneous Mastocytosis
    1. Isolated skin Mast Cell accumulation
    2. Most cases are in children (80% of cases are age <1 year old)
  2. Systemic Mastocytosis
    1. Diffusely increased Mast Cells in Bone Marrow, Spleen, and liver
    2. Most cases are in adults (95% of adult cases)

V. Causes: Triggers for Mast Cell Degranulation

  1. Medications (e.g. Opioids, NSAIDs, iodinated contrast, Vancomycin, general Anesthesia)
  2. Physical stimuli (e.g. Exercise, extremes of Temperature, emotional stress)
  3. Surgical procedures
  4. Bites and Stings (e.g. Insect Bites, Animal Bites)

VI. Findings: Cutaneous Mastocytosis

  1. Pruritus
  2. Urticaria Pigmentosa
    1. Red-Brown Macules or Papules

VII. Findings: Systemic Mastocytosis

VIII. Labs

  1. Complete Blood Count
    1. Anemia -mild to moderate (50% of cases)
    2. Eosinophilia (25% of cases)
    3. Monocytosis (50% of advanced cases)
  2. Mastocytosis specific lab markers
    1. Serum Tryptase >20 ng/ml (systemic mastocytocytosis)
    2. Urine 24 hour collection for Histamine or Histamine Metabolites
  3. Skin Biopsy of Urticaria Pigmentosa
    1. Mast Cell aggregation
  4. Bone Marrow Biopsy
    1. Spindle-shaped Mast Cells
    2. Distribution in perivascular, peritrabecular and intertrabecular areas
  5. Other advanced testing
    1. KIT Gene Mutation Analysis

IX. Management

  1. Symptomatic Management
    1. Antihistamines for Pruritus
    2. Aspirin for Flushing (adults)
  2. Urticaria Pigmentosa
    1. PUVA
    2. Corticosteroids (severe cases)
  3. Gastrointestinal Symptoms
    1. Mast Cell Stabilizers (e.g. Disodium Chromoglycate)
    2. Proton Pump Inhibitors or H2 Blockers (e.g. Pepcid)

X. References

  1. Castells and Akin in Saini (2017) Mastocytosis Evaluation and Diagnosis, UpToDate, accessed 10/5/2020
  2. Mahmoudi (2014) Immunology Made Ridiculously Simple, MedMaster, Miami, FL, p. 30-1

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Related Studies

Ontology: Mastocytosis (C0024899)

Definition (NCI) A clonal myeloproliferative neoplasm characterized by the proliferation and accumulation of neoplastic mast cells in one or multiple organs or organ systems. It is a heterogeneous group of neoplasms, ranging from cutaneous proliferations which may regress spontaneously, to aggressive neoplasms associated with organ failure and short survival.
Definition (CSP) rare disease characterized by an abnormal increase in mast cells in the bone marrow, liver, spleen, lymph nodes, gastrointestinal tract, and skin.
Definition (MSH) A heterogenous group of disorders characterized by the abnormal increase of MAST CELLS in only the skin (MASTOCYTOSIS, CUTANEOUS), in extracutaneous tissues involving multiple organs (MASTOCYTOSIS, SYSTEMIC), or in solid tumors (MASTOCYTOMA).
Concepts Disease or Syndrome (T047)
MSH D008415
ICD10 Q82.2
SnomedCT 78745000, 125541005, 397007003
English Disease, Mast-Cell, Diseases, Mast-Cell, Mast-Cell Disease, Mast-Cell Diseases, Mastocytoses, mast cell hyperplasia, MAST CELL DISEASE, MASTOCYTOSIS, MAST CELL DIS, Mastocytosis, Mastocytosis [Disease/Finding], cell disorders mast, cell diseases mast, mastocytoses, mast cell disorder, mast cell disease, Mast Cell Disease, mastocytosis (diagnosis), anomalies of skin mastocytosis, mastocytosis, Mast cell disease, Mast cell disorder (disorder), Mast cell disorder, Mast cell hyperplasia (morphologic abnormality), Mast cell hyperplasia, disease; mast cell, mast cell; disease
Swedish Mastocytos
Japanese ヒマンサイボウショウ, 肥胖細胞症, 肥満細胞症, マストサイトーシス, 肥満細胞増多症, 肥満細胞病, 良性肥満細胞腫, 肥満細胞腫-良性
Czech mastocytóza, Mastocytóza
Finnish Mastosytoosi
German Mastozytose (angeboren), Mastozytose, Mastzellerkrankung
Korean 비반세포증
Polish Mastocytoza
Hungarian mastocytosis
Norwegian Mastocytose
Dutch mastocytose, mestcel; ziekte, ziekte; mestcel, Mastocytose, Mestcelziekte
Spanish Enfermedad Mastocitaria, hiperplasia de mastocitos (anomalía morfológica), hiperplasia de mastocitos, mastocitosis, trastorno de mastocitos (trastorno), trastorno de mastocitos, Mastocitosis, Enfermedad de Mastocitos
Portuguese Doença Mastocitária, Mastocitose, Doença de Mastócitos
French Mastocytose bénigne, Mastocytose
Italian Mastocitosi

Ontology: Urticaria Pigmentosa (C0042111)

Definition (NCI) The most frequent form of cutaneous mastocytosis. In children, the lesions tend to be papular, and are characterized by aggregates of elongated or spindle-shaped mast cells which fill the papillary dermis and extend into the reticular dermis. In adults, the lesions tend to have fewer mast cells compared to those in children. The lesions are located most commonly on the trunk, but they can be seen on the extremities, head and neck. (WHO, 2001)
Definition (MSH) The most common form of cutaneous mastocytosis (MASTOCYTOSIS, CUTANEOUS) that occurs primarily in children. It is characterized by the multiple small reddish-brown pigmented pruritic macules and papules.
Definition (CSP) most common form of mastocytosis, characterized by multiple persistant small reddish brown hyperpigmented pruritic macules and papules.
Concepts Disease or Syndrome (T047) , Congenital Abnormality (T019)
MSH D014582
ICD10 Q82.2
SnomedCT 205566001, 703828003, 78745000
Swedish Urticaria pigmentosa
English URTICARIA PIGMENTOSA, urticaria pigmentosa (diagnosis), urticaria pigmentosa, Urticaria Pigmentosa [Disease/Finding], mastocytosis, pigmentosa urticaria, Cutaneous Mastocytoses, Maculopapular, Cutaneous Mastocytosis, Maculopapular, Maculopapular Cutaneous Mastocytoses, Maculopapular Cutaneous Mastocytosis, Urticaria pigmentosa (morphologic abnormality), Urticaria pigmentosa, Localised cutaneous mastocytosis, Localized cutaneous mastocytosis, Urticaria pigmentosa (disorder), pigmentation; congenital, urticaria pigmentosa, pigmentosa; urticaria, urticaria; pigmentosa, Localized cutaneous mastocytosis, NOS, Urticaria pigmentosa, NOS, Urticaria pigmentosa [Ambiguous], UP/MPCM, Urticaria Pigmentosa/Maculopapular Cutaneous Mastocytosis, Urticaria Pigmentosa
Japanese シキソセイジンマシン, 蕁麻疹-色素性, 色素じんましん, 色素性じんま疹, 色素性蕁麻疹, じんましん-色素性, 色素じんま疹, 色素性じんましん, 色素蕁麻疹
Czech urticaria pigmentosa, Urticaria pigmentosa
Finnish Keltatäpläurtikaria
Italian Mastocitosi cutanea maculopapulare, Orticaria pigmentosa
Polish Pokrzywka barwnikowa
Hungarian Urticaria pigmentosa
Norwegian Urticaria pigmentosa
Dutch pigmentatie; congenitaal, urticaria pigmentosa, pigmentosa; urticaria, urticaria; pigmentosa, urticaria pigmentosa, Urticaria pigmentosa, Cutane maculopapulaire mastocytose, Mastocytose, cutane, maculopapulaire
Spanish mastocitosis cutánea localizada, urticaria pigmentosa (trastorno), urticaria pigmentosa, Urticaria pigmentosa, Mastocitosis Cutánea Maculopapular, Urticaria Pigmentosa
Portuguese Urticária pigmentar, Mastocitose Cutânea Maculopapular, Urticaria Pigmentosa
German Urtikaria pigmentosa, Urticaria pigmentosa
French Mastocytose cutanée éruptive, Urticaire pigmentaire

Ontology: Mastocytosis, Systemic (C0221013)

Definition (NCI) A variant of mastocytosis characterized by multifocal, dense infiltrates of mast cells (15 or more mast cells in aggregates) detected in the bone marrow and/or other extracutaneous sites. (WHO, 2001) -- 2003
Definition (NCI_NCI-GLOSS) A rare disease in which too many mast cells (a type of immune system cell) are found in the skin, bones, joints, lymph nodes, liver, spleen, and gastrointestinal tract. Mast cells give off chemicals such as histamine that can cause flushing (a hot, red face), itching, abdominal cramps, muscle pain, nausea, vomiting, diarrhea, low blood pressure, and shock.
Definition (MSH) A group of disorders caused by the abnormal proliferation of MAST CELLS in a variety of extracutaneous tissues including bone marrow, liver, spleen, lymph nodes, and gastrointestinal tract. Systemic mastocytosis is commonly seen in adults. These diseases are categorized on the basis of clinical features, pathologic findings, and prognosis.
Concepts Disease or Syndrome (T047)
MSH D034721
SnomedCT 123310005, 50150000, 397016004
Swedish Mastocytos, systemisk
Japanese ゼンシンセイヒマンサイボウショウ, 肥満細胞症-全身性, 全身性肥満細胞症
Finnish Systeeminen mastosytoosi
Czech Systémová mastocytóza, systémová mastocytóza, mastocytóza systémová
English Mastocytosis, Systemic [Disease/Finding], mastocytosis systemic, systemic mast cell disease, systemic mastocytosis, systemic urticaria pigmentosa, systemic mast-cell disease, Systemic mastocytosis (disorder), Mast-Cell Disease, Systemic, Mast-Cell Diseases, Systemic, Mastocytoses, Systemic, Mastocytosis, Systemic, Systemic Mast Cell Disease, Systemic Mast-Cell Disease, Systemic Mast-Cell Diseases, Systemic Mastocytoses, Systemic mastocytosis, NOS, Systemic tissue mast cell disease, Systemic mastocytosis, SMCD - systemic mast cell disease, Systemic mast cell disease (disorder), Systemic mast cell disease, disease (or disorder); systemic tissue, mast cell, systemic; mast cell disease, Systemic mastocytosis -RETIRED-, Systemic Mastocytosis, Systemic Tissue Mast Cell Disease
French Mastocytose systémique, Mastocytose généralisée
Polish Mastocytoza układowa
Hungarian systemás mastocytosis
Dutch systemische mastocytose, aandoening; systemisch weefsel, mestcel, systemisch; mestcelaandoening, Mastocytose, systemische, Systemische mestcelziekte
Norwegian Systemisk mastocytose
Spanish mastocitosis sistémica - RETIRADO - (concepto no activo), mastocitosis sistémica - RETIRADO -, Enfermedad de Mastocitos Sistémica, enfermedad sistémica de los mastocitos (trastorno), enfermedad sistémica de los mastocitos, enfermedad sistémica de mastocitos hísticos, Mastocitosis sistémica, Enfermedad Sistémica de Mastocitos, Mastocitosis Sistémica
Portuguese Doença de Mastócitos Sistêmica, Mastocitose sistémica, Doença Sistêmica de Mastócitos, Mastocitose Sistêmica
German systemische Mastozytose, Mastozytose, systemische, Systemische Mastozytose
Italian Mastocitosi sistemica

Ontology: Cutaneous Mastocytosis (C1136033)

Definition (NCI) A form of mastocytosis characterized by mast cell infiltration of the skin. (WHO, 2001) -- 2003
Definition (MSH) Skin lesions due to abnormal infiltration of MAST CELLS. Cutaneous mastocytosis is confined to the skin without the involvement of other tissues or organs, and is mostly found in children. The three major variants are: URTICARIA PIGMENTOSA; diffuse cutaneous mastocytosis; and SOLITARY MASTOCYTOMA OF SKIN.
Concepts Neoplastic Process (T191)
MSH D034701
SnomedCT 703827008, 397012002
Swedish Mastocytos, kutan
Czech mastocytóza kožní
Finnish Ihon mastosytoosi
Japanese 水疱性肥満細胞症, 瀰漫性皮膚肥満細胞症, 肥満細胞症-水疱性, び漫性皮膚肥満細胞症, 肥満細胞症-びまん性皮膚, びまん性皮膚肥満細胞症, 皮膚肥満細胞症, 肥満細胞症-皮膚, 水疱性肥満細胞腫
English Mastocytosis, Cutaneous [Disease/Finding], Cutaneous Mastocytoses, Mastocytoses, Cutaneous, Mastocytoses, Skin, Mastocytosis, Cutaneous, Mastocytosis, Skin, Skin Mastocytoses, Skin Mastocytosis, Cutaneous mastocytosis (morphologic abnormality), Cutaneous mastocytosis (disorder), Cutaneous mastocytosis, Cutaneous Mastocytosis, CM
Polish Mastocytoza skórna
Norwegian Mastocytose i huden, Kutan mastocytose
Spanish Mastocitosis Bullosa, Mastocitosis Bulosa, mastocitosis cutánea (trastorno), mastocitosis cutánea, Mastocitosis de la Piel, Mastocitosis Cutánea
French Mastocytose cutanée
German Haut-Mastozytose, Kutane Mastozytose, Mastozytose der Haut, Mastozytose, kutane
Italian Mastocitosi cutanea
Dutch Cutane mastocytose, Huidmastocytose, Mastocytose, cutane, Mastocytose, huid-
Portuguese Mastocitose da Pele, Mastocitose Cutânea