Evaluation Of Clinical Diagnosing Standard For Neonatal Septicemia

Objective: To evaluate practice-value of the current diagnosing standard for neonatal septicemia and related items, and to explore a better diagnosing criteria.Methods: The database of 285 neonates suspected to have the probable septicemia between June 2007 and June 2008 was reviewed, including the results of blood culture and cerebrospinal culture, clinical manifestation, white blood count (WBC), immature to total neutrophil rate (I/T), blood platelet count (PLT), C reaction protein(CRP), heart rate, the level of the hemobilirubin and creatine kinase-MB (CK-MB). First,We would determine the correct diagnosis(septicemia or'no septicemia')for each case depending on collected clinical data.Then we would analyze all the data by following methods:(1)evaluate the diagnosing value of the current diagnosing standard for neonatal septicemia and each evaluated item in our study by calculating their diagnosing sensitivity and specificity;(2)evaluate the relationship between septicemia and each evaluated item byχ2 test and logistic regression,then figure out the new diagnosing standards for neonatal septicemia according to the weighted clinical score(WCS)and unweighted clinical score(UWCS)criterias by employing the items (P<0.05)related with septicemia as the diagnosing items,and compare the diagnosing value between WCS and UWCS creterias by receiver operating characteristic(ROC)curve;(3)determine the optimal diagnosing cut-off points of the WCS and UWCS criterias according to the principle its diagnosing accuracy(Youden index)was highest,and compare them with the current diagnosing standard.Results:1. Among the investigated 285 cases, there're 87'definite septicemia'cases and 160'no septicemia'cases, both of whom enrolled to our study. The main bacterias isolated from blood cultures of'definitive cases'are: Staphylococcus epidermidis 26.4% (23 cases), Staphylococcus haemolysis 16.1% (14 cases), Escherichia coli 9.2% (8 cases), Spore bacteria 9.2% (8 cases), klebsiella spp 8.0% (7 cases).2. Among all the evaluated items, the ranking order of sensitivity are CK-MB, clinical manifestations, jaundice,and their respective sensitivity are 76.3%,71.3%,57.1%; the order on specificity are heart rate, I/T, PLT, CRP, jaundice,WBC,and their respective specificity are 99.4%, 96.2%, 95.5%, 93.5%,88.2%,87.3%;The items that are different between'definite septicemia'group and'no septicemia'group are clinical manifestations, I/T, CRP, jaundice, heart rate ,and their respective logistic regression coefficient are 0.836,1.228,1.461,2.332,2.936 . 3. The areas under the ROC curves for WCS and UWCS diagnosing criterias are 0.845(95% confidence interval 0.791-0.900)and 0.794(95% confidence interval 0.731-0.856),respectively。4. The diagnosing sensitivity,specificity and Youden index for current diagnosing standard and the optimal diagnosing points(total WCS=12 or 15 and total UWCS=2) of WCS and UWCS criterias are : 14.1%,99.4%, 0.235;79.4%,81.0%,0.604;54.4%,85.7%,0.401.Conclusions:1. The sensitivity of the clinical items (WBC,I/T,CRP,PLT) is low, but their specitivity is high. The diagnosing value of the two items (WBC, PLT) needs to be tested further.2. The jaundice and heart rate do closely relate to neonatal septicemia, and may be used as the diagnosing items.3. The diagnosing value of the current diagnosing standard for neonatal septicemia is low,especially for the diagnosing sensitivity and Youden index, although its diagnosing specificity is very high.4. We find it can improve the diagnosing value significantly by employing the five items (I/T, CRP, jaundice, heart rate and clinical manifestations) as the diagnosing items,especially for the sensitivity,and the WCS criteria is better than UWCS.