OBJECTIVETo study the value of Pentraxin 3 (PTX3) in diagnosing the severity and cardiovascular function of the critically ill children. Method A total of 178 patients who were older than 28 days, with acute infection of respiratory or neurological system, excluding chronic or special disease, and admitted to the pediatric intensive care unit (PICU) of Hunan Children's Hospital from October 1, 2013 to April 30, 2014 were enrolled, including 102 male cases and 76 female cases. The ages ranged from 1 month to 13 years and 1 month, 78 of them were less than 1 year old ; 58 cases were between 1 to 3 years old; 42 cases were above 3 years old; 101 cases were diagnosed as respiratory system diseases, 77 cases had nervous system diseases. PTX3 was detected with enzyme-linked immunosorbent assay (ELISA) within 1 d after enrollment, at 3 days and 7 days, meanwhile, troponin, myocardial enzyme, brain-type natriuretic peptide (BNP), C-reactive protein (CRP), plasma calcitonin (PCT) and WBC etc. Were measured. According to the plasma PTX3 value which were measured within 24 h after enrollment the patients were divided into three groups: mildly elevated group (< 44 µg/L) 41 cases; moderately elevated group (44 - < 132 µg/L) in 66 cases; severely elevated group 71 cases (132 µg/L or higher). Those 178 patients were divided into 3 groups according to the degree of infection: non-sepsis group (78 cases), sepsis group (70 cases), severe sepsis group (30 cases), and in each group, those with heart failure were respectively 19 cases, 28 cases, 17 cases. Analysis of the plasma PTX3 expression changes in different clinical manifestations, different condition, different degrees of organ damages and prognosis for the patient. The continuous variables were analyzed with t-test, F-test, H-test, the categorical variables were analyzed with Chi-square test, and the correlation analysis was performed to calculate Pearson coefficients.

RESULTThe PTX3 value measured within 24 h after enrollment increased with the degree of infection (50. 4(35. 2,70. 4) µg/L; 175. 8 (99. 6, 309. 9) µg/L;419. 9 (168. 3, 468. 6) µg/L; H = 88. 345, P = 0. 000). PTX3 level gradually declined, while in severe sepsis group decreased slowly (P <0. 05); the area under the ROC curve of Plasma PTX3 was larger than that of other inflammatory markers such as CRP and PCT, white blood cells and neutrophils in the diagnosis of sepsis; while the former three are PTX3, PCT and CRP (the sensitivity and specificity respectively were 0. 77, 0. 68; 0. 66, 0. 6; 0. 47, 0. 55); the PTX3 value of the severely elevated group was significantly higher than those of the mildly and moderately elevated groups (P <0. 05). The proportion of having 3 or more organs failure increased as the PTX3 rising among the groups of mildly elevated group, moderately elevated group and severely elevated group (1(2. 4%), 4(6. 1%), 14(19. 7%) χ2 =16. 16,P = 0. 000); and in each group, the proportion of having good and poor prognosis for these three groups were different (33 (80.5%) and 8 (19. 5%), 35 (53%) and 31 (47%), 28 (39.4%) and 43 (60.6%), χ = 17. 663, P = 0. 000). The K-M curve for these three groups had statistically significant difference (χ2 = 7. 086, P = 0. 029). Those with heart failure had higher PTX3 value than those in non-heart failure at the same degree of infection. PTX3 value increased with myocardial enzyme (troponin, creatine kinase isoenzyme, BNP) levels. In the diagnosis of heart failure, the area under the ROC curve were respectively PTX3 0. 824; BNP 0. 772; CM-KB 0. 643; CNTIO. 671, the sensitivity and specificity were PTX3 0. 8, 0. 58; CK-MB 0. 56,0. 79; CTNI 0. 60,0. 69; BNP 0. 73, 0. 58. In terms of predicting the prognosis of sepsis with heart failure complications, the PTX3 value's area under ROC curve was larger than that of BNP (respectively 0. 844, 0. 472).

CONCLUSIONThe PTX3 is an objective biochemical marker in diagnosis of sepsis; it is helpful in assessment of severity and prognosis of sepsis; it also has a certain clinical value in the assessment of sepsis cardiovascular function damage.