Serum Tryptase and Urinary 1-Methylhistamine as Parameters for Monitoring Oral Food Challenges in Children

Abstract

To study the usefulness of urinary 1-methylhistamine and serum tryptase concentration as monitoring parameters in clinical settings, we investigated 32 children with atopic dermatitis and suspected food allergy during oral food challenges with eggs and cow’s milk. Urinary 1-methylhistamine (MH) excretion increased significantly within lh after positive oral food challenges (p < 0.006), but showed considerable variation in negative challenges. MH seems to be a sensitive parameter (92.8%), but its specifity is insufficient (37.7%). In the group of 16 positive oral food challenges serum tryptase concentration increased significantly (p < 0.02) directly after provocation and remained elevated up to 2 h after provocation. No variation was observed in negative challenges or nonatopic controls. Serum tryptase concentration seems to be specific for marked clinical reactions after oral food challenges (100%), but its sensitivity was low (25%) and not superior to evaluation by clinical means. We conclude that, despite positive results for the group of children, MH and serum tryptase concentrations are not useful parameters for monitoring oral food challenges in an individual child due to insufficient sensitivity and specificity.

Standardizing double-blind, placebo-controlled oral food challenges: American Academy of Allergy, Asthma & Immunology–European Academy of Allergy and Clinical Immunology PRACTALL consensus report

“…Some investigators have reported significant increases in urinary 1-methylhistamine levels 1 hour after a positive OFC result, as well as a significant increase in serum tryptase levels, but the sensitivity of these parameters is low. 90 Similar results were observed by Ohtsuka et al 91 when measuring plasma tryptase and histamine levels up to 4 hours after a positive challenge result but were not confirmed by others for eosinophil cationic protein level in the blood and tryptase levels in the blood or saliva. 92 …”

Changes in Blood Leukocyte Distribution during Double-Blind, Placebo-Controlled Food Challenges in Children with Atopic Dermatitis and Suspected Food Allergy

“…In addition, in patients with positive oral food challenges, an increase in serum tryptase (mast-cell-specific mediator) [31], plasma histamine [32] and urinary 1-methylhistamine [31] was also observed in the first hours, suggesting that eosinophils, basophils and mast cells react early. The ongoing reaction seems to be triggered and controlled by lymphocytes.…”

Enhanced histamine metabolism: a comparative analysis of collagenous colitis and food allergy with respect to the role of diet and NSAID use

“…In our patients with food allergy, diagnosed by allergological and standardised challenge procedures [15,19,20], gastrointestinal manifestation are predominant. The most characteristic finding was a significant reduction of the intensity of abdominal pain during a hypoallergenic diet consisting of potato and rice.…”

“…During the first two days, patients consumed a normal, unrestricted diet. This was followed by a two day period with an elimination diet consisting exclusively of potatoes and rice [20,21]. Food intake was allowed until 2 p.m., but no later to avoid interference of histamine containing foods (such as fish or cheese) [22].…”