Mast Cell Activation Disorders

Abstract

Background and Objectives: Mast cell disorders comprise a wide spectrum of syndromes caused by mast cells’ degranulation with acute or chronic clinical manifestations. Materials and Methods: In this review article we reviewed the latest findings in scientific papers about mast cell disorders with a particular focus on mast cell activation syndrome and mastocytosis in pediatric age. Results: Patients with mast cell activation syndrome have a normal number of mast cells that are hyperreactive upon stimulation of various triggers. We tried to emphasize the diagnostic criteria, differential diagnosis, and therapeutic strategies. Another primary mast cell disorder is mastocytosis, a condition with a long-known disease, in which patients have an increased number of mast cells that accumulate in different regions of the body with different clinical evolution in pediatric age. Conclusions: Mast cell activation syndrome overlaps with different clinical entities. No consensus was found on biomarkers and no clearly resolutive treatment is available. Therefore, a more detailed knowledge of this syndrome is of fundamental importance for a correct diagnosis and effective therapy.

Mastocytosis and Mast Cell Activation Disorders: Clearing the Air

“…The typical syndrome is characterized by (1) pathological accumulation of mast cells in organs and tissues and/or (2) aberrant release of ≥mast cell mediators. MCAS are classified as primary clonal (clonal disorders which include systemic mastocytosis and its variants, cutaneous mastocytosis, and the clonal mast cell activating syndrome (CMCAS) or monoclonal mast cell activating syndrome (MMAS)) and the non-clonal mast cell activating syndromes, including secondary, idiopathic, and combined disorders ( Table 1 ) [ 27 , 28 , 52 , 80 , 81 ]. Patients with mastocytosis meet the World Health Organization (WHO) criteria for either cutaneous or systemic disease [ 31 ].…”

Case Report: Hereditary Alpha Tryptasemia in Children: A Pediatric Case Series and a Brief Overview of Literature

“…If the basal tryptase level is ≥20.0 ng/ml, the likelihood of systemic mastocytosis is high, and a bone marrow biopsy is warranted. Normal or slightly elevated basal serum tryptase levels (11.5–20.0 ng/ml) do not rule out the diagnosis, and highly sensitive polymerase-chain-reaction techniques for KIT D816V transcripts in peripheral-blood leukocytes could be used to confirm or exclude the clinical suspicion ( 29 ). For patients in whom the KIT mutation is detected in peripheral blood, a bone marrow evaluation is indicated ( 11 ).…”

Gastrointestinal Manifestations in Systemic Mastocytosis: The Need of a Multidisciplinary Approach

“…Additionally, up to 4% of the general population presents a recently described autosomal dominant-inherited genetic feature called hereditary alpha-tryptasemia (HαT) [27,28]. Individuals with this genetic trait have extra copies of the MC tryptase gene TPSAB1 encoding for serum tryptase that result in high baseline serum tryptase level > 8 ng/mL.…”

“…Individuals with this genetic trait have extra copies of the MC tryptase gene TPSAB1 encoding for serum tryptase that result in high baseline serum tryptase level > 8 ng/mL. Clinical symptoms in HαT are variable, including flushing, urticaria, and GI manifestations, therefore simulating MC disorders [28]. Interestingly, in this setting of individuals, Hamilton et al recently found an increase in duodenal MCs, usually more than 20 MCs/HPF, in clusters < 15 MCs, but without signs of clonality [29].…”