No evidence of increased serum substance P levels in chronic urticaria patients with and without demonstrable circulating vasoactive factors.
The neuropeptide substance P is a possible candidate as histamine-releasing factor in some patients with chronic ordinary urticaria (COU), particularly in those with evidence of a nonautoantibody circulating histamine-releasing factor. In this study, serum substance P levels were measured by enzyme immunoassay in 117 COU patients, 40 atopic subjects and 24 normal subjects. In vivo and in vitro assays for histamine-releasing factors, autologous serum skin test (ASST) and basophil histamine release (BHR) assay, respectively, were performed in all COU patients. Mean serum substance P concentration was not significantly different in COU patients and in normal subjects; however, significantly higher levels were detected in atopic subjects than in COU patients (P < 0.003). ASST and BHR assays allowed us to distinguish different subsets of COU patients. Mean serum substance P concentration did not vary significantly in the different subsets of patients. Nevertheless, interestingly three patients with positive ASST and negative BHR assay showed very high substance P levels. These results suggest that substance P does not play an important role as histamine-releasing factor in COU in general but only in occasional patients in whom it might act as a trigger of urticarial symptoms.
Tedeschi
A
A
Second Division of Internal Medicine, IRCCS Ospedale Maggiore Policlinico, Milano, Italy. albited@aliceposta.it
Lorini
M
M
Asero
R
R
D000328:Adult; D015549:Basophil Degranulation Test / Q000379:methods; D014408:Biomarkers, Tumor / Q000097:blood*; D002908:Chronic Disease; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000097:blood / Q000276:immunology; D012882:Skin Tests / Q000379:methods; D013373:Substance P / Q000097:blood*; D000090324:Tumor Protein, Translationally-Controlled 1; D014581:Urticaria / Q000097:blood* / Q000276:immunology
D014408:Biomarkers, Tumor; D000090324:Tumor Protein, Translationally-Controlled 1; D013373:Substance P