Serum-Tryptase

Finally, patients suffering from mastocytosis have a higher risk of developing severe anaphylaxis after an insect sting [34]. In venom-allergic patients with mastocytosis, elevated baseline serum tryptase levels were foimd to be associated with severe anaphylactic reactions to stings [35]. 

Bonadonna P, Perbellini O, Passalacqua G, et al Clonal mast cell disorders in patients with systemic reactions to Hymenoptera stings and increased serum tryptase levels. J Allergy Clin Immunol 2009 123 680-686. 

Florian S, Krauth MX, Simonitsch-Klupp I, et al Indolent systemic mastocytosis with elevated serum tryptase, absence of skin lesions, and recurrent severe anaphylactoid episodes. Int Arch Allergy 43 Immunol 2005 136 273-280. 

A fatal anaphylactoid reaction to an intravenous nonionic contrast medium occurred during a CT scan (225). The authors highlighted the value of measuring serum tryptase in the diagnosis of anaphylactoid reactions. 

This patient had all the features of anaphylactoid reactions, which include pulmonary and laryngeal edema and a massive rise in serum tryptase. The half-Ufe of tryptase is about 2 hours. Moderately raised post-mortem tryptase activity in the absence of anaphylaxis has been described. Therefore, only very high serum tryptase activity, as seen in this case, should be regarded as specific for fatal anaphylactoid reactions. 

A 28-year-old woman who was taking metformin 1500 mg/day for polycystic ovary syndrome underwent hysterosalpingography for secondary infertility and 4 hours later developed severe epigastric pain, nausea and vomiting, shivering, and a temperature of 38.1°C. She had leukopenia (1.0 x 10 /1) and a blood film showed a shift to the right with minimal immature forms. The serum tryptase concentration was not raised. The full blood count improved after about 3 hours. Clinically she improved within a few hours and the blood count was normal after 48 hours. 

Determination of serum tryptase levels sampled at appropriate time intervals preferably within 6-8 h of the reaction. More than one sample should be taken if possible. 

Raised serum tryptase concentrations and immunoglobin E to suxamethonium confirmed anaphylaxis to suxamethonium in these two patients. Hypotension was refractory to terlipressin in both cases and to extracorporeal membrane oxygenation in one. However, both interventions were instituted after a prolonged period of resuscitation. Methythioninium chloride, glucagon, and ai-adrenoceptor agonists have been proposed as alternative therapeutic options in... 

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