Cytokine profiles after nonionic dimeric contrast medium injection.

Mediators of contrast media (CM)-induced allergic/pseudoallergic side effects are largely unknown. We evaluated the possibility of cytokines released as surrogate markers for allergic/pseudoallergic responses in patients who tolerated CM injection well. Interleukin-1beta (IL-1beta), -2, -4, -5, -6; tumor necrosis factor-alpha; plasma histamine level; and the anaphylatoxin C5a were measured by enzyme-linked immunosorbent assay technique in 9 patients who received the nonionic dimeric iodinated CM iotrolan under routine computed tomography examination conditions. Serum samples were collected before, 1 hour, 6 hours, and 24 hours after contrast medium injection. The cytokine values did not correlate with the hematocrit. Kinetic studies revealed a trend, although not statistically significant (P>0.05), for an early increase of IL-2 (1 hour after CM), followed by delayed increase of IL-4 and IL-6. Histamine significantly decreased after iotrolan injection and C5a increased 6 hours (P>0.05) after CM administration in parallel to IL-6. IL-1beta decreased (with the lowest value measured 6 hours after CM injection; P>0.05), and tumor necrosis factor-alpha did not show any tendency. Patients with late adverse reactions had a T helper 1 to T helper 2 shift and 24 hours after CM injection had the highest histamine values. The results suggest CM-related liberation of cytokines with a sequential T helper type 1 (IL-2 after 1 hour), and T helper type 2-like pattern (IL-4, -5, and -6).