I read with interest an article \"Updated meta-analysis of pancreatic stent placement in preventing post-endoscopic retrograde cholangiopancreatography pancreatitis\" by Fan and colleagues in World J Gastroenterol 2015; 21(24): 7577-7583. Although I appreciate their work, I have found problems with the data extracted and analyzed by the authors, and will give my comment in this letter. It would be valuable if the authors could provide an accurate estimation of their extracted data.

UNASSIGNED: Evidence shows that rectal indomethacin (RI) reduces the risk of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) in high-risk patients. The prophylactic role of RI in low-risk patients has not yet been identified. The objective of our study was to evaluate the impact of RI in preventing PEP in low-risk patients.
UNASSIGNED: A retrospective cohort study was conducted to evaluate the impact of RI in preventing PEP. RI was available starting November 2012. Patient characteristics and procedure details were collected.
UNASSIGNED: The study population included 2238 patients who underwent ERCP (1055 in the RI group and 1183 in the control group). PEP was diagnosed in 107 patients (4.8%). In a multivariate model of consecutive patients, RI reduced the incidence of PEP by 55% (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.36-0.94; P=0.03). In a multivariate model that included 1874 (84%) low-risk patients, RI reduced the incidence of PEP by 62% (OR 0.38, 95%CI 0.19-0.74; P=0.004). Propensity-matched group analysis was performed for low-risk native papilla patients. RI reduced the incidence of PEP by 61% (OR 0.39, 95%CI 0.18-0.8; P=0.009).
UNASSIGNED: RI reduced PEP in consecutive as well as low-risk patients. RI should be administrated in consecutive patients unless contraindicated. Larger prospective studies are needed to confirm our results.

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is essential for managing biliary and pancreatic disorders. Infection is the most morbid complication of ERCP and among the most common causes of ERCP-related death.
METHODS: A 69-year-old man presented with right upper quadrant abdominal pain, obstructive jaundice and abnormal liver function tests. Ultrasound revealed cholelithiasis without bile duct dilation. After receiving intravenous antibiotics for acute cholecystitis, the patient was discharged. Two weeks later, an endoscopic ultrasound demonstrated gallstones and CBD dilation of up to 6.4 mm with 2 filling defects. An ERCP was performed with a papillotomy and stone extraction. Twenty-four hours post-ERCP the patient developed a fever, chills, bilirubinemia and elevated liver function tests. Ascending cholangitis was empirically treated using Ceftriaxone and Metronidazole. However, the patient remained febrile, with a diffusely tender abdomen and elevated inflammatory markers. A CT revealed a very small hypodense lesion in the seventh liver segment. Extended-spectrum beta-lactamase positive Klebsiella Pneumonia and Enterococcus Hirae were identified, and the antibiotics were switched to Imipenem and Cilastatin. The hypodense lesion in the liver increased to 1.85 cm and a new hypodense lesion was seen in the right psoas. At day 10 post-ERCP, the patient started having low back pain and difficulty walking. MRI revealed L4-L5 discitis with a large epidural abscess, spanning L1-S1 and compressing the spinal cord. Decompressive laminectomy of L5 was done and Klebsiella pneumonia was identified. Due to continued drainage from the wound, high fever, we performed a total body CT which revealed increased liver and iliopsoas abscess. Decompressive laminectomy was expanded to include L2-L4 and multiple irrigations were done. Gentamycin and Vancomycin containing polymethylmethacrylate beads were implanted locally and drainage catheters were placed before wound closure. Multidisciplinary panel discussion was performed, and it was decided to continue with a non invasive approach .
CONCLUSIONS: Early recognition of complications and individualized therapy by a multi-disciplined team is important for managing post-ERCP septic complications. Particular attention should be given to adequate coverage by empiric antibiotics.

OBJECTIVE: To determine the efficacy of rectally administered naproxen for the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP).
METHODS: This double-blind randomized control trial conducted from January 2013 to April 2014 at the Gastrointestinal and Liver Diseases Research Center in Rasht, Iran. A total of 324 patients were selected from candidates for diagnostic or therapeutic ERCP by using the simple sampling method. Patients received a single dose of Naproxen (500 mg; n = 162) or a placebo (n = 162) per rectum immediately before ERCP. The overall incidence of PEP, incidence of mild to severe PEP, serum amylase levels and adverse effects were measured. The primary outcome measure was the development of pancreatitis onset of pain in the upper abdomen and elevation of the serum amylase level to > 3 × the upper normal limit (60-100 IU/L) within 24 h after ERCP. The severity of PEP was classified according to the duration of therapeutic intervention for PEP: mild, 2-3 d; moderate 4-10 d; and severe, > 10 d and/or necessitated surgical or intensive treatment, or contributed to death.
RESULTS: PEP occurred in 12% (40/324) of participants, and was significantly more frequent in the placebo group compared to the naproxen group (P < 0.01). Of the participants, 25.9% (84/324) developed hyperamylasemia within 2 h of procedure completion, among whom only 35 cases belonged to the naproxen group (P < 0.01). The incidence of PEP was significantly higher in female sex, in patients receiving pancreatic duct injection, more than 3 times pancreatic duct cannulations, and ERCP duration more than 40 min (Ps < 0.01). There were no statistically significant differences between the groups regarding the procedures or factors that might increase the risk of PEP, sphincterotomy, precut requirement, biliary duct injection and number of pancreatic duct cannulations. In the subgroup of patients with pancreatic duct injection, the rate of pancreatitis in the naproxen group was significantly lower than that in the placebo (6 patients vs 23 patients, P < 0.01, RRR = 12%, AR = 0.3, 95%CI: 0.2-0.6). Naproxen reduced the PEP in patients with ≥ 3 pancreatic cannulations (P < 0.01, RRR = 25%, AR = 0.1, 95%CI: 0.1-0.4) and an ERCP duration > 40 min (P < 0.01, RRR = 20%, AR = 0.9, 95%CI: 0.4-1.2).
CONCLUSIONS: Single dose of suppository naproxen administered immediately before ERCP reduces the incidence of PEP.