Cutaneous Mastocytosis in Children: Analysis of Somatic and Germline Mutations

Pediatric mastocytosis is an orphan disease, which encompasses several clinically distinct entities including solitary mastocytoma, urticaria pigmentosa, diffuse cutaneous mastocytosis and the newly recognized mast cell activation syndrome. The most common form of pediatric mastocytosis is cutaneous maculopapular mastocytosis (CMPM), also known as urticaria pigmentosa (UP). There are significant knowledge gaps regarding the genetic basis of pediatric mastocytosis and the functional activity of mast cells in this condition. The Pediatric Dermatology and Pediatric Oncology services at the University of Minnesota Masonic Children's Hospital are seeing significant growth in clinical volumes of pediatric mastocytosis, including rare, familial cases. The aims of this study are to prospectively explore germline risk for UP and to perform a mutational analysis to identify somatic mutations, beyond those currently identified, in pediatric patients with UP.

Sex

All

Minimum age

3 Months

Maximum age

23 Years

Inclusion Criteria:

Affected subject:

Subjects will be eligible to participate in the study if all of the following conditions exist:

1. Clinical diagnosis of urticaria pigmentosa/cutaneous mastocytosis with representative skin lesions
2. Age \<23 years
3. Capable of giving consent if 18 or older

Inclusion Criteria for Parent:

1. Over 16 years of age
2. Biologic parent to affected subject
3. Capable of providing consent

Inclusion Criteria for Sibling:

1\. Biologic sibling to affected subject 2. Capable of giving consent if 18 or older

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Exclusion Criteria:

1. Absence of skin findings representative of classic urticaria pigmentosa
2. Patients with primarily systemic mastocytosis
3. Unable or unwilling to participate in study procedures

Exclusion Criteria for Parent/Sibling:

1\. Unable or unwilling to participate in study procedures

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