Objective      To investigate the changes in serum levels of interleukin-4 (IL-4)

interferon-γ（IFN-γ）and urinary level of leukotriene E

4

(LTE

4

) in infants with asthmatic diseases and their significances.   

    Methods      Serum levels of IL-4 and IFN-γ and urinary levels of LTE

4

were measured by competitive ELISA in 22 infants with acute and convalescence asthmatic diseases (asthmatic group)

20 infants with acute non-asthmatic diseases but with respiratory tract infection (non-asthmatic group)

and 20 healthy infants (normal control group). The ratio of IL-4 to IFN-γ and the correlations between urinary LTE

4

and serum IL-4

and between urinary LTE

4

and serum IFN-γ were analyzed.       Results      The serum levels of IL-4 in acute asthma period was obviously higher than that of acute non-asthma and normal control（P0.05

0.01）. The serum levels of IFN-γ in acute asthma period was significantly lower than those of acute non-asthma and normal control（P0.01）. The urinary levels of LTE

4

in acute asthma period was higher than normal control group（P0.01）

but were not significantly different from acute non-asthma （P0.05）. In remission/convalescence

the serum levels of IL-4 were lower than those of acute period (P0.01)

but were still higher than normal control group (P0.01). The serum levels of IFN-γ were higher than those of acute period (P0.01)

but were still lower than normal control group (P0.01). The urinary levels of LTE

4

were obviously lower than those of acute period (P0.01)

but were still higher than normal control (P0.01). The ratio of IL-4 to IFN-γ in acute asthma period was higher than that of acute non-asthma and normal control group（F=15.86，P0.01）.In remission

the ratio of IL-4 to IFN-γ was lower than that in acute period (t=4.14

P0.01)

but was still higher than normal control group (P0.01). There was positively correlation between urinary LTE

4

and serum IL-4 levels in the acute stage in asthmatic group（r=0.82

P0.01）. There was negative correlation between urinary LTE

4

and serum IFN-γ levels in the acute stage in asthmatic group（r=-0.81

P0.01).       Conclusion      IL-4

IFN-γ and LTE

4

may all be involved in th

e pathogenesis of respiratory tract inflammation in infant with asthmatic diseases. There are immune imbalance of Th1/Th2 in infant with wheezing.