title: Clinical significance of melatonin concentrations in predicting the severity of acute pancreatitis.
abstract: OBJECTIVE
  To assess the value of plasma melatonin in predicting acute pancreatitis when combined with the acute physiology and chronic health evaluation II (APACHEII) and bedside index for severity in acute pancreatitis (BISAP) scoring systems.
  
  
  METHODS
  APACHEII and BISAP scores were calculated for 55 patients with acute physiology (AP) in the first 24 h of admission to the hospital. Additionally, morning (6:00 AM) serum melatonin concentrations were measured on the first day after admission. According to the diagnosis and treatment guidelines for acute pancreatitis in China, 42 patients suffered mild AP (MAP). The other 13 patients developed severe AP (SAP). A total of 45 healthy volunteers were used in this study as controls. The ability of melatonin and the APACHEII and BISAP scoring systems to predict SAP was evaluated using a receiver operating characteristic (ROC) curve. The optimal melatonin cutoff concentration for SAP patients, based on the ROC curve, was used to classify the patients into either a high concentration group (34 cases) or a low concentration group (21 cases). Differences in the incidence of high scores, according to the APACHEII and BISAP scoring systems, were compared between the two groups.
  
  
  RESULTS
  The MAP patients had increased melatonin levels compared to the SAP (38.34 ng/L vs 26.77 ng/L) (P = 0.021) and control patients (38.34 ng/L vs 30.73 ng/L) (P = 0.003). There was no significant difference inmelatoninconcentrations between the SAP group and the control group. The accuracy of determining SAP based on the melatonin level, the APACHEII score and the BISAP score was 0.758, 0.872, and 0.906, respectively, according to the ROC curve. A melatonin concentration ≤ 28.74 ng/L was associated with an increased risk of developing SAP. The incidence of high scores (≥ 3) using the BISAP system was significantly higher in patients with low melatonin concentration (≤ 28.74 ng/L) compared to patients with high melatonin concentration (> 28.74 ng/L) (42.9% vs 14.7%, P = 0.02). The incidence of high APACHEII scores (≥ 10) between the two groups was not significantly different.
  
  
  CONCLUSIONS
  The melatonin concentration is closely related to the severity of AP and the BISAP score. Therefore, we can evaluate the severity of disease by measuring the levels of serum melatonin.
authors.affiliation: Department of Gastroenterology, First Affiliated Hospital of Wenzhou Medical College, Wenzhou 325000, Zhejiang Province, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Jin
authors.forename: Chun-Jing
authors.initials: CJ
authors.lastname: Lin
authors.forename: Le-Mei
authors.initials: LM
authors.lastname: Dong
authors.forename: Meng-Jun
authors.initials: MJ
authors.lastname: Chen
authors.forename: Qiong
authors.initials: Q
authors.lastname: Zhou
authors.forename: Jian-Sheng
authors.initials: JS
authors.lastname: Wu
mesh_terms: D018806:APACHE; D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008550:Melatonin / Q000097:blood*; D008875:Middle Aged; D010195:Pancreatitis / Q000097:blood* / Q000175:diagnosis*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D015415:Biomarkers; D008550:Melatonin
keywords: Acute physiology and chronic health evaluation II; Bedside index for severity in acute pancreatitis; Cutoff; Melatonin concentrations; Pancreatitis; Predict