[The value of pro-adrenomedullin in early diagnosis of sepsis].

OBJECTIVE: To explore the early diagnostic value of pro-adrenomedullin (pro-ADM) in sepsis.

METHODS: A prospective study was conducted. Eighty-two patients with acute infection admitted to Department of Emergency of Shanxi Medical University Second Hospital from April 2013 to March 2014 were enrolled. According to the diagnostic criteria of sepsis, the patients with acute infection were divided into ordinary infection group [infection without systemic inflammatory response syndrome (SIRS), n = 25] and sepsis group (infection combined with SIRS, n = 57). According to degree of severity of sepsis, the latter group was subdivided into three subgroups: sepsis group (n = 22), severe sepsis group (n = 27) and septic shock group (n = 8). Twenty-four healthy persons were included to serve as healthy control group. The venous blood from all the research objects in hospital was collected within 24 hours. The levels of pro-ADM and procalcitonin ( PCT ) were determined by enzyme linked immunosorbent assay (ELISA), and acute physiology and chronic health evaluation II (APACHE II ) score was recorded. The relationship between pro-ADM and PCT and also APACHE II score was analyzed with Pearson correlation analysis. The receiver-operating characteristic curve (ROC) of pro-ADM and PCT were used to evaluate the diagnostic acuity of sepsis.

RESULTS: The plasma levels of pro-ADM, PCT and APACHE II score in sepsis group were significantly higher than those in ordinary infection group and healthy control group [pro-ADM (ng/L): 66.69 ± 1.73 vs. 53.43 ± 2.70, 45.87 ± 1.43; PCT (ng/L): 1 336.49 ± 40.26 vs. 1 083.09 ± 47.99, 959.04 ± 37.53; APACHE II score: 14.60 ± 0.81 vs. 8.10 ± 1.14, 3.00 ± 1.15, all P < 0.01]. With the aggravation of sepsis, the levels of pro-ADM, PCT and APACHE II score were gradually increased, and there were significant differences among sepsis, severe sepsis, and septic shock groups [pro-ADM (ng/L): 64.91 ± 2.50, 73.56 ± 2.80, 84.67 ± 4.52; PCT (ng/L): 1 152.65 ± 48.62, 1 233.93 ± 63.06, 1 475.71 ± 109.93; APACHE II score: 12.91 ± 1.15, 14.55 ± 1.14, 19.37 ± 2.40, P < 0.05 or P < 0.01]. Pearson correlation analysis results showed that the level of pro-ADM was positively related with PCT (r = 0.473, P = 0.006), and it was also positively correlated with APACHE II score (r = 0.707, P = 0.008). ROC curve analysis showed that area under the ROC curve (AUC) of pro-ADM for diagnosis of sepsis was 0.823 (P = 0.003). When the cutoff value was 59.40 ng/L, the sensitivity was 80.7%, the specificity was 68.0%, the positive predictive value was 85.2%, and the negative predictive value was 60.7%. AUC of the PCT for diagnosis of sepsis was 0.653 (P = 0.043). When the cutoff value was 1 194.67 ng/L, the sensitivity was 68.4%, the specificity was 64.0%, the positive predictive value was 81.8%, and the negative predictive value was 44.7%. It was proved that the pro-ADM had a higher diagnostic value for sepsis than PCT.

CONCLUSION: The plasma levels of pro-ADM can be used as an early indicator in diagnosis and severity evaluation and prognosis in patients with sepsis.