Pediatr Allergy Respir Dis.  2007 Dec;17(4):394-403.

Correlation between the Diagnostic Validity of Enzymeimmunoassay and the Hyperreactivity of the Respiratory Tract for the Diagnosis of Mycoplasma pneumoniae

• Kim HJ
• Nam SY
• Yoon HS
• Kim WK

Abstract

PURPOSE:Mycoplasma pneumoniae (M. pneumoniae) is one of the common causes of lower respiratory tract diseases. Several studies have suggested that respiratory infection by M. pneumoniae may be associated with a reactive airway disease and asthma. In order to find such relationships, we compared the particle agglutination test with enzyme immunoassay (EIA) which were checked on the 1st, and at 1 and 5 or 7 days of follow-up. We also evaluated EIA in association with bronchial hypersensitivity.
METHODS
One hundred eleven children who were out patients or hospitalized with pneumonia at Inje University and Hallym University Hospitals were included in the study. Patients were grouped according to the M. pneumoniae antibody titer. Patients who showed initial M. pneumoniae antibody titer and EIA Immunoglobulin (Ig) G/IgM greater than 1:320 were designated as group 1 (n=46). In group 2 (n=33), patients showed initial M. pneumoniae antibody titer lower than 1:320 but it increased more than fourfold between acute and convalescent stages. Group 3 (n=32) was a control group. We measured eosinophil counts, the total IgE, and the eosinophil cationic protein (ECP). Thirty-five children were checked with the methacholine test 3 or 4 months, after the first visit. Bronchial hypersensitiveness was defined positive if the concentration of methacholine was less than the lower limit (8 mg/mL methacholine).
RESULTS
All 111 patients participated in the particle agglutination test at the initial and convalescent stages. The sensitivity and specificity for EIA were obtained from the results of the particle agglutination test. The sensitivity and specificity of acute and convalescent EIA IgG were 44.3% and 90.6%, and 67.1% and 96.9%, respectively. The sensitivity and specificity of acute and convalescent EIA IgM were 60.8% and 100%, and 92.4% and 100%, respectively. The M. pneumoniae antibody titer was associated with hospitalized days and improvement of chest X-rays. Only in group 3, the M. pneumoniae antibody titer correlated with the ECP level, but there was no significant difference between the methacholine test and eosinophil counts.
CONCLUSION
The results of this study suggest that EIA may be a useful diagnostic method for detecting early phase of M. pneumoniae infection.

Keyword

Mycoplasma pneumoniae; Asthma; Immunoenzyme techniques; Agglutination test

MeSH Terms

Agglutination Tests
Asthma
Child
Diagnosis*
Eosinophil Cationic Protein
Eosinophils
Follow-Up Studies
Hospitals, University
Humans
Hypersensitivity
Immunoenzyme Techniques
Immunoglobulin E
Immunoglobulin G
Immunoglobulin M
Immunoglobulins
Methacholine Chloride
Mycoplasma pneumoniae*
Mycoplasma*
Outpatients
Pneumonia
Pneumonia, Mycoplasma*
Respiratory System*
Respiratory Tract Diseases
Sensitivity and Specificity
Thorax
Eosinophil Cationic Protein
Immunoglobulin E
Immunoglobulin G
Immunoglobulin M
Immunoglobulins
Methacholine Chloride