OBJECTIVENeonatal septicemia is a critical disease in neonatal period. Its incidence among live births is between 1 per thousand and 8 per thousand. Mortality of neonatal septicemia may be as high as 50% for infants who are not treated. The early signs of septicemia in the newborn are generally nonspecific. Blood culture and the other clinical diagnostic measures are not sufficiently sensitive. The present study aimed at evaluating potential use of soluble intercellular adhesion molecule-1 (sICAM-1), procalcitonin (PCT) and C-reactive protein (CRP) in diagnosis of septicemia.

METHODSThe experimental group consisted of 50 newborns with septicemia who were treated in Hebei Provincial Children's Hospital from April 1, 2002 to December 30, 2002. Thirty of the 50 cases had positive blood culture. The control group included 35 healthy newborns. Fasting blood samples were taken for bacterial cultures and sICAM-1, CRP, PCT determination. PCT and CRP contents were determined immediately after the specimens were collected. Analyses of sICAM-1 were done after inclusion of the last patient. Serum was separated from each specimen and stored at -20 degrees C within 2 hours. The analyses of sICAM-1 were performed by ELISA technique. CRP was analyzed by immunoturbidimetry assay (ITA). Immunochromatographic test was performed for detection of PCT from 200 ul serum. SPSS 10.0 was used to process the data. P values < 0.05 was considered to be statistically significant. One way analysis of variance (ANOVA), multiple comparison, chi-square test, paired-samples T test, linear correlation, Spearman correlation analysis, ROC curve were used for statistical analysis. The sensitivity, specificity, positive and negative predictive values, accuracy, Youden's index for sICAM-1, PCT, CRP and WBC count were calculated. These values were compared with each other.

RESULTS(1) The content of sICAM-1 in control group varied widely from 79 to 1252 ng/ml. Comparison of the data indicated that there was significant difference among the three groups in the content of sICAM-1, CRP and PCT (P < 0.05), but not in WBC count. These markers are considered positive if sICAM-1 >or= 300 ng/ml, CRP >or= 8 mg/l, PCT >or= 2 ng/ml. Their sensitivity was higher than WBC (P < 0.05). Among these indices, PCT has the highest specificity (94.3%), positive predictive (95.6%), negative predictive (82.5%), accuracy (89.4%), and Youden's index (80.3%). (2) No significant difference was found in sICAM-1 between pre- and post-treatment (P > 0.05); however, there was significant difference in CRP and PCT. (3) sICAM-1 was in direct proportion to CRP (r = 0.339,P < 0.01). PCT is correlated with sICAM-1, CRP (the spearman correlation coefficient 0.569, 0.482, P < 0.01).

CONCLUSIONDifferent individual is in different immune status; The level of sICAM-1 is related with neonatal septicemia. sICAM-1 concentration may be used as a diagnostic tool with high sensitivity (85%) and moderate specificity (54.3%) in neonates suspected of infection. The sensitivity and specificity of CRP (>or= 8 mg/l) were accordingly 87.5% and 54.3%. WBC count had low sensitivity for diagnosis (30.0%); Among these indices, PCT had the highest specificity (94.3%), positive predictive (95.6%), negative predictive (82.5%) Values, accuracy (89.4%), Youden's index (80.3%); No correlation was found between sICAM-1 concentration and their ages in day accordingly. CRP, PCT may be used to estimate the effect of therapy. The correlation of the infectious indices indicates that the body may mobilize many organs at the same time to resist the invasion of organism.