INFANTILE
FIRST LOWER RESPIRATORY TRACT INFECTIONS AND DYSFUNCTIONAL SERUM IgG
SUBCLASSES
Dai J-H
Children’s Hospital, Chongqing University of
Medical Science, Chongqing, China
Objective: To study the
relationship between first lower respiratory tract infections and changes
of serum IgG subclasses.
Methods: One hundred and eighty-five infants with first
lower respiratory tract infections were selected randomly to detect serum
IgG, IgA, IgM and IgG subclasses by ELISA. The findings were compared with the
reference values of the serum IgG, IgA, IgM and IgG subclasses from local
healthy infants. The findings that were below the lower limits of reference
values (x-1.96s) were regarded as Ig or IgG subclass deficiency,while that
were beyond the upper limits of
reference values(x+1.96s) were regarded as Ig or IgG subclass
increasing.
Results: There were 43 patients with IgG deficiency had
IgG subclass deficiency out 185 cases. And 120 cases of IgG subclass
deficiency were found in 142 patients left whose IgG levels were normal.
The total rate of incidence of IgG subclass deficiency was 84.51%. Among
patients from birth to three months old, there were 29 cases of three and
four kinds of IgG subclass deficiency and the rate was 85.29% which was the
highest in all ages.
Conclusions: We found that IgG subclass deficiency
indeed existed in infants with first lower respiratory tract infections. It
was more common to have IgG subclass deficiency in infants when the
patients were much younger. Therefore what should be noticed is not only
the total serum IgG level but also serum IgG subclass concentration in
infantile first lower respiratory tract infections.