A W van Toorenenbergen1, A P Oranje. 1. Department of Clinical Chemistry, University Medical Center Rotterdam, Erasmus MC, Dr. Molewaterplein 40, P.O. Box 2040, 3000 CA Rotterdam, The Netherlands. a.w.vantoorenenbergen@erasmusmc.nl
Abstract
BACKGROUND: The disease extent of mastocytosis can be assessed by measurement of mediators or their metabolites, secreted from mast cells. In the present study, we compared results of urinary N-methylhistamine measurements with analysis of total tryptase in serum from patients with suspected mastocytosis. METHODS: Tryptase in serum was determined with the UniCAP tryptase fluor-enzyme-immunoassay, according to the manufacturers' instructions (Pharmacia, Woerden, Netherlands). N-methylhistamine in urine was determined by competitive radioimmunoassay, according to the manufacturers' instructions (Pharmacia). RESULTS: A significant correlation between serum tryptase and urine N-methylhistamine was found both for 138 patients aged 14 or older (Spearman Rank r(s)=0.43, p<0.0001) and for 23 younger patients (Spearman Rank r(s)=0.46, p=0.0267). The between-run coefficient of variation of the tryptase assay was half (6.7%) of the one (13%) found with the urinary N-methylhistamine assay. Both for urine N-methylhistamine and serum tryptase, a significant difference was found between corresponding biopsies with an increased number of mast cell aggregates and biopsies without such an increase. The difference between tryptase levels however was stronger (Mann-Whitney: p=0.0012) than the difference between N-methylhistamine levels (Mann-Whitney: p=0.0140). CONCLUSION: Serum tryptase discriminates better than urinary N-methylhistamine between patients with an increased number of mast cell aggregates and persons without such an increase.
BACKGROUND: The disease extent of mastocytosis can be assessed by measurement of mediators or their metabolites, secreted from mast cells. In the present study, we compared results of urinary N-methylhistamine measurements with analysis of total tryptase in serum from patients with suspected mastocytosis. METHODS: Tryptase in serum was determined with the UniCAP tryptase fluor-enzyme-immunoassay, according to the manufacturers' instructions (Pharmacia, Woerden, Netherlands). N-methylhistamine in urine was determined by competitive radioimmunoassay, according to the manufacturers' instructions (Pharmacia). RESULTS: A significant correlation between serum tryptase and urine N-methylhistamine was found both for 138 patients aged 14 or older (Spearman Rank r(s)=0.43, p<0.0001) and for 23 younger patients (Spearman Rank r(s)=0.46, p=0.0267). The between-run coefficient of variation of the tryptase assay was half (6.7%) of the one (13%) found with the urinary N-methylhistamine assay. Both for urine N-methylhistamine and serum tryptase, a significant difference was found between corresponding biopsies with an increased number of mast cell aggregates and biopsies without such an increase. The difference between tryptase levels however was stronger (Mann-Whitney: p=0.0012) than the difference between N-methylhistamine levels (Mann-Whitney: p=0.0140). CONCLUSION: Serum tryptase discriminates better than urinary N-methylhistamine between patients with an increased number of mast cell aggregates and persons without such an increase.
Authors: Peter Valent; Cem Akin; Michel Arock; Knut Brockow; Joseph H Butterfield; Melody C Carter; Mariana Castells; Luis Escribano; Karin Hartmann; Philip Lieberman; Boguslaw Nedoszytko; Alberto Orfao; Lawrence B Schwartz; Karl Sotlar; Wolfgang R Sperr; Massimo Triggiani; Rudolf Valenta; Hans-Peter Horny; Dean D Metcalfe Journal: Int Arch Allergy Immunol Date: 2011-10-27 Impact factor: 2.749
Authors: Milda Vysniauskaite; Hans-Jörg Hertfelder; Johannes Oldenburg; Peter Dreßen; Stefan Brettner; Jürgen Homann; Gerhard J Molderings Journal: PLoS One Date: 2015-04-24 Impact factor: 3.240