Definition

Mastocytosis a rare skin or blood disorder in which large accumulations of mast cells (a type of white blood cell) is detected in the skin and / or other organs. Systemic mastocytosis, which accounts for most cases, usually has a genetic mutation in hereditary genes.

Children with mastocytosis are investigated and treated by specialist pediatric patients (pediatrics), adults with a specialist in blood disorders (hematologist).

Mastocytosis triggers episodes of allergy-like symptoms, including stomach pain with diarrhea, exhaustion and mood swings occur

• In some cases, rheumatism occurs joint pain, backache or muscle aches

Occurrence

Mastocytosis is defined as one rare disease.

Symptoms

Mastocytosis in the skin

Children most often have symptoms that are limited to the skin in the form of severe itching, eczema and "flushing»(Episodes of strong red and warm skin). Most people get symptoms already in their first year of life. The symptoms usually return within adulthood

• The symptoms are often triggered by physical irritation ( Dari sign) or heat

Urticaria pigmentosa are the most common form of skin manifestation in children and adults. Typically, yellow-red-brownish spots may be slightly swollen. They can be misinterpreted as freckles. There are also other forms of disease that attack the skin

• More unusual is hives (urticaria) or angioedema
  • Consider allergies and other causes of illness

Systemic mastocytosis

Systemic mastocytosis is the most common form among adults (95%)

• Often the combination of skin symptoms (see above) and other organs
  • Abdominal pain, nausea and diarrhea
  • Skeletal pain and muscles
  • Osteoporosis (osteoporosis)
  • Mood swings with depression

Triggering factors

• Heat or cold
• Acute stress (physical, emotional)
• Alcohol or strong spices
• Medications (Acetylsalicylic acid / ASA, NSAIDs)
• Infections
• Anesthesia, Narcosis, Operations
• Insect bites

Blood tests

• Anemia (low hemoglobin, 50%)
• Eosinophilic (a type of white blood cell 25%)
• Tryptase is often increased

Diagnosis

The diagnosis is based on a combination of the following:

• Symptoms
• Exclusion of other common causes
• Tryptase is too high in the blood
• Tissue sample
• Use of criteria (see below)
• Genetic test for KIT mutation

Criteria for diagnosis

Criterion for diagnosis is based on tissue sample, special blood cell test and Tryptase (at least one main criterion or three sub-criteria) (Reference: Leguit R, 2019)

Main Criterion

• Dense infiltrate of more than 15 mast cells in tissue sample (biopsy) from bone marrow or other non-skin organ

under Criteria

• Detection of unusual mast cells (positive for CD2 and / or CD25)
• Detection of unusual mast cells (coil-shaped)
• Detection of mutation in KIT (D816V)
• Tryptase in blood sample greater than 20 ng / ml

Other mast cell diseases

• Mast cell activation syndrome (MCAS)
  • Similar symptoms like Mastocytosis, but without typical findings in biopsy
  • Details of MCAS here (reference: Valent P, 2019)
• Mastocytosis associated with blood cancer
  • Mast cell leukemia
• Mast cell sarcoma

Incorrect diagnosis (similar conditions, differential diagnoses)

• Other diseases with eosinophilia (please read here)
• Anaphylaxis
• Hereditary angioedema
• Carcinoid syndrome
• Mast cell activation syndrome (MCAS, reference Valent P, 2019)
• Medullary thyroid cancer
• Vasoactive intestinal peptide secreting tumor (VIP tumor)
• Reactive (secondary) mastocytosis (activated by other underlying diseases)
• Pheochromocytoma
• Tryptase increase for other reasons
  • Myeloproliferative disease
  • Myelodysplastic disease
  • Chronic renal failure
  • Chronic liver failure
  • Chronic eosinophilic leukemia
• Fibromyalgia
• Systemic lupus erythematosus
• Dermatomyositis

Treatment

No treatment with drugs ensures full relief of symptoms.

• Allergy drugs (histamine antagonist)
• Stomach acid inhibitor (proton pump inhibitor)
• Kaldribin (Mavenclad) Interferon and the tyrosine kinase inhibitor midostaurin (Rydapt) is used. In some is done stem cell transplant (as in systemic sclerosis)

Literature

• Leguit R, 2019 (Severe mastocytosis)
• Czarny J, 2018 (cutaneous form)
• Macri A, 2018 (Urticaria pigmentosa)
• Desmond DH, 2018 (Systemic Mastocytosis)
• Johansen S, 2019

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