Clonal mast cellMast cell A type of white blood cell produced in the bone marrow. They help defend against infections and play a key role in allergic reactions. In SM, mast cells become overactive and build up throughout the body. diseases (CMDs) such as systemic mastocytosis (SM) are a significant risk factor for sting reactions (STs) and venom immunotherapy (VIT) adverse reactions, according to a recently published study in The Journal of Allergy and Clinical Immunology: In Practice.
“Hymenoptera venom-induced anaphylaxisAnaphylaxis A severe allergic reaction that can turn fatal without treatment. Patients with SM are at a higher risk of developing anaphylaxis. is a severe and potentially fatal allergic reaction 71 that occurs rapidly after the sting. In the USA, the prevalence of systemic sting reactions 72 (SSR) among adults can reach up to 3.3%, while European epidemiological studies report prevalence rates as high as 7.5%,” the authors wrote.
Research shows that patients with high serum tryptaseTryptase A protein enzyme that is primarily produced by mast cells and stored in small pockets within the cells, known as granules. High levels of tryptase are a key indicator of SM. levels should undergo diagnostic testing for CMDs. Testing for a KIT p.D816V mutation through PCR assay is of particular importance in these cases.
Even patients with asymptomatic SM can suffer from severe STs; in fact, a severe ST can be the first clinical manifestation of SM.
Learn more about SM causes and risk factors
The Spanish Network on MastocytosisMastocytosis Rare disease caused by the buildup of mast cells. Cutaneous mastocytosis primarily affects the skin and is more common in children, while systemic mastocytosis affects internal organs and is more common in adults. (REMA) developed a screening tool based on laboratory and clinical findings to rule out SM in patients who develop STs. It uses baseline tryptase levels and clinical hallmarks such as dizziness and skin SM symptoms.
VIT is the preventive treatment of choice for patients with CMDs who suffer from STs. However, VIT can produce severe adverse effects. Important risk factors for VIT adverse reactions include the presence of preexisting cardiovascular or pulmonary disorders and elevated basal serum tryptase. CMDs are not associated with higher risk.
“We now have a more detailed understanding of risk factors for severe SSR and sAE during 307 VIT. Elevated BST levels, CMD, and higher age are well-established risk factors for severe 308 SSR,” the authors concluded.
