Plasma histamine and tumour necrosis factor-alpha levels in Crohn's disease and ulcerative colitis at various stages of disease.

Mast cells secrete numerous mediators and this study investigated plasma levels of histamine, and tumor necrosis factor alpha (TNF-α) in chronic inflammatory bowel disease (IBD). Plasma levels of histamine were determined in 68 patients with Crohn's disease (CD), 22 with ulcerative colitis (UC) and 13 controls. TNF-α levels were assessed in 29 CD patients, 11 UC patients, and in 11 controls. Plasma histamine levels in the control group were 0.25 ng (0.14 - 0.33) and showed no difference to CD (0.19 ng, 0.09 - 0.35) or UC (0.23 ng, 0.11 - 0.60). Significantly lower histamine levels were only found in CD patients on 5-aminosalicylic acid treatment (P ≤ 0.04). Plasma TNF-α levels in the control group were significantly lower 0.44 ml/m(2) (0 - 1.15) than in CD patients (4.62 ml/m(2), 1.82 - 9.22, P = 0.005) or UC (3.14 ml/m(2); 0.08 - 11.34, P = 0.01). In CD disease activity, fistula, and extraintestinal manifestations (EM) were associated with significantly higher plasma TNF-α values, but not the type of treatment. We concluded that in contrast to TNF-α, histamine levels were normal in CD and UC. There is no correlation with histamine and thus the proportion of TNF-α secreted from mast cells in the plasma in patients with IBD is less important.