We assayed 38 middle ear effusions from 23 children aged 4-13 years (mean 7
) undergoing tympanostomy tube placements. All fluid was assayed for tumor
necrosis factor (TNF) alpha, interleukin (IL) 1 beta, IL-8, and IL-10. Cyto
kine concentrations were measured by means of an enzyme-linked immunosorben
t assay. Detectable levels of IL-1 beta, IL-8, and IL-10 were found in all
of the effusions. TNF-alpha was detected in 18 of the middle ear effusions
(47.4%). The mean concentration of TNF-alpha, IL-1 beta, IL-8, and IL-10 wa
s, respectively, 0.423 +/- 1.39, 30.58 +/- 68.7, 7001.9 +/- 6743, and 56 +/
- 58.7 pg/ml. There was a strong, statistically significant correlation bet
ween the concentrations of TNF-alpha and IL-1 beta (r = 0.87, P = 0.001) an
d between IL-1 beta and IL-8 (r = 0.53, P = 0.001). There was no correlatio
n between the concentrations of IL-10 and other cytokines examined or betwe
en tympanic membrane pathology and the concentrations of TNF-alpha, IL-1 be
ta, IL-8, or IL-10. The presence of IL-10 in middle ear effusions may be on
e of the causes of a lack of clinical features of acute inflammation and ma
y lead to a chronic inflammatory state.