[Expression of neutrophil adhesion molecule CD11b as an early diagnostic marker for neonatal sepsis].

OBJECTIVE: Neonatal sepsis is a common disease and the sepsis-related mortality rate is still high. Until now, there has no ideal diagnostic marker to early identify neonatal sepsis. Expression of neutrophil adhesion molecule CD(11b) was showed as the earlier reaction to the infection/inflammation, and may be applied as an early diagnostic marker for sepsis. This study was to investigate this antigen for early diagnosis of neonatal sepsis related to bacterial infection. METHODS: According to clinical symptoms, signs and four indices (WBC, PLT, plasma CRP and ratio of I/T), fifty-one neonates with established or suspected sepsis were allocated retrospectively into two groups of sepsis [n = 23, gestational age of (38.3 +/- 2.4) weeks, postnatal age of (12.7 +/- 8.8) days, body weight: (3.1 +/- 0.8) kg] and suspected sepsis [n = 28, gestational age of (38.8 +/- 1.6) weeks, postnatal age of (11.7 +/- 7.3) days, body weight: (3.3 +/- 0.6) kg]. Fifteen healthy neonates were served as controls [gestational age: (38.5 +/- 1.4) weeks, postnatal age: (8.2 +/- 5.5) days, body weight: (3.3 +/- 0.3) kg]. CD(11b) was quantified with the whole blood flow cytometry and direct immunofluorescence technique. RESULTS: The expressions of neutrophil CD(11b) in neonates with sepsis and suspected sepsis were (320 +/- 189) MFI and (456 +/- 213) MFI, respectively, which was lower than that of controls [(1,090 +/- 338) MFI, t = -9.01 and -7.56, respectively; P < 0.001]. The expression of CD(11b) was lower in neonates with sepsis than that with suspected sepsis (t = -2.39, P < 0.05). The expression of CD(11b) in neonates with CRP >or= 30 mg/L was (211 +/- 164) MFI, which was lower than those with CRP < 30 mg/L [(505 +/- 265) MFI, t = 2.64, P < 0.05]. The detection of CD(11b) (