To evaluate the early diagnosis and clinical significance of detection of immunoglobulin M(IgM) combinded with myeloperoxidase(MPO) in neonates with bacterial infection.

From July 2007 to July 2008, 25 full-term neonates who were confirmed by bacterial detection of blood, urine, cerebrospinal fluid, and the culture of umbilical secretions were randomly selected into infected group. The other 25 full-term neonates without bacterial infection were chosen as control group. Both groups detected the level of immunoglobulin M and myeloperoxidase by nephelometry and colorimetry. Informed consent was obtained from all participants.

The concentrations of immunoglobulin M in serum and myeloperoxidase in pre-therapy of infected group and control group were (0.51±0.14) g/L and (0.57±0.11)△A/min, (0.24±0.14)g/L and (0.17±0.08)△A/min, respectively. There had significant difference between the pre-therapy of infected group and control group (P<0.05). However, the concentration of immunoglobulin M in serum increased to (0.64±0.13)g/L and myeloperoxidase reduced to (0.25±0.09)△A/min in second sampling in post-therapy of infected group, the significant difference was found in the concentration of immunoglobulin M in serum and myeloperoxidase between before and after the treatment in infected group (P<0.05).

The detection of concentration of immunoglobulin M in serum and myeloperoxidase are valuable for early diagnosis of bacterial infection in newborns.