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Normal and anomalous pancreaticobiliary union in children and adolescents
Normal and anomalous pancreaticobiliary union in children and adolescents Moises Guelrud, MD, Claudio Morera, MD, Magaly Rodriguez, MD, Jose G. Prados, MD, Domingo Jaén, MD Caracas, Venezuela
Background: The normal length of the pancreaticobiliary union (common channel) in the pediatric population is not known, nor is the frequency of anomalous pancreaticobiliary union and the extent to which it is associated with pancreaticobiliary disease. Methods: ERCP was performed on 136 patients younger than 1 year (group 1) and 128 older than 1 year (group 2). Results: In group 1 the average length of the common channel was 1.8 ± 0.61 mm with a maximal length of 3 mm (mean plus 2 standard deviations). In group 2 the average length and maximal length of the common channel increased with age. In the 1 to 3 year age range the average length was 2.2 ± 0.47 mm with a maximal length of 2.7 mm, in the 4 to 6 year range it was 2.8 ± 0.40 mm (3.6 mm maximal), in the 7 to 9 year range it was 3.2 ± 0.43 mm (4.1 mm maximal), in the 10 to 12 year range it was 3.9 ± 0.5 mm (4.4 mm maximal), and in the 13 to 15 year range it was 4.0 ± 0.51 mm (5 mm maximal). The prevalence of the anomalous pancreaticobiliary union was 25% (66/264). In group 1 the anomaly was present in 4.4% (6 of 136) of patients, 1.3% (1/76) with neonatal hepatitis, 4.6% (3/44) with biliary atresia, and 100% (2/2) with choledochal cyst. In group 2 the anomaly was present in 46.9% (60/128) of patients, 100% (57/57) with choledochal cyst and 15.7% (3/19) with idiopathic recurrent pancreatitis without bile duct dilatation. Conclusions: The mean length of the common channel increases with age. The maximum normal length of the common channel in neonates and infants younger than 1 year is 3 mm. It increases with age to a maximum of 5 mm in children and adolescents between 13 and 15 years of age. Anomalous pancreaticobiliary union is relatively common among children and adolescents undergoing ERCP in our center, including those with idiopathic recurrent pancreatitis (15.7%). ERCP is valuable in the diagnosis of this anomaly. (Gastrointest Endosc 1999;50:189-93.)
Anomalous pancreaticobiliary union (ABPU) is a congenital malformation of the pancreaticobiliary tree in which the confluence of the common bile duct and pancreatic duct is outside the duodenal wall. A common channel for bile and pancreatic secretion ordinarily is formed by the absence of the septum between the biliary and pancreatic ducts as they approach the ampulla of Vater. In adults, the normal length of the common channel at ERCP is 4.5 mm with a range of 1 to 12 mm.1,2 APBU is considered to be present when the common channel as demonstrated with ERCP measures more than 15 mm1 or when its extraduodenal portion is more than 6 mm long.3 However, these measurements cannot be applied to the pediatric population. In this study we established the normal length of the common channel in pediatric and adolescent
Received April 29, 1998. For revision August 27, 1998. Accepted January 14, 1999. From the Gastroenterology Department and Pediatric Gastroenterology Unit, Hospital General del Oeste, Caracas Venezuela. Reprint requests: Moises Guelrud, MD, Policlínica Metropolitana, Urb. Caurimare, Calle A1, Caracas 1060, Venezuela. Copyright © 1999 by the American Society for Gastrointestinal Endoscopy 0016-5107/99/$8.00 + 0 37/1/97113 VOLUME 50, NO. 2, 1999
patients, assessed the frequency of APBU among our patients, and examined the association between this anomaly and pancreaticobiliary disease. PATIENTS AND METHODS We retrospectively reviewed 264 consecutive ERCP studies performed during the last 12 years on pediatric patients with suspected pancreaticobiliary disease. The patients were classified into two age groups. Group 1 included neonates and infants younger than 1 year for whom ERCP was performed to evaluate neonatal cholestasis. Group 2 included patients between 1 and 19 years of age in whom ERCP was performed to evaluate intermittent jaundice or recurrent pancreatitis. For children younger than 3 years ERCP was performed with pediatric duodenoscopes (Prototype PJF with an external diameter of 8.5 mm and the standard PJF with an external diameter of 7.5 mm; Olympus America, Inc., Melville, N.Y.). For older children a standard duodenoscope (JF-1T; Olympus) was used. For 34 infants older than 3 months in group 1 and for all patients in group 2 the procedure was performed with conscious sedation with a combination of meperidine (2 to 4 mg/kg, maximum 100 mg) administered intravenously with diazepam (0.1 to 0.3 mg/kg, maximum 15 mg) or midazolam (0.1 to 0.3 mg/kg, maximum 15 mg). General anesthesia was used for 6 neonates. Continuous monitoring of heart rate GASTROINTESTINAL ENDOSCOPY
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Normal and anomalous pancreaticobiliary union in children and adolescents
Figure 3. ERCP shows anomalous pancreaticobiliary union of type long Y without common bile duct dilatation in a 30day-old neonate with biliary atresia. Figure 1. ERCP shows anomalous pancreaticobiliary union of type BP in a 12-year-old girl with choledochal cyst.
Figure 2. ERCP shows anomalous pancreaticobiliary union of type PB in a 4-year-old girl with choledochal cyst. 190
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and capillary oxygen saturation was maintained during ERCP and during the postprocedural period until full recovery was achieved. All procedures were performed on an ambulatory basis. Patients were discharged in 2 to 4 hours, and guardians were instructed in recognition of signs and symptoms of complications and the procedure for obtaining medical assistance. A 5F ERCP catheter was used, and to achieve good visualization of the common channel the papilla was cannulated just at its tip. Four to six radiographs were available for each patient. Only ERCP studies in which the terminal common channel was clearly opacified were evaluated. To account for magnification, the distal end of the duodenoscope was measured, and the measurement of the length of the common channel was adjusted accordingly. Patients with ERCP findings of pancreas divisum, annular pancreas, and biliary atresia type 14 in which there was no visualization of the biliary duct were excluded. Among patients with insufficient pancreatic duct visualization, the absence of an incidental pancreas divisum or annular pancreas could not be determined. APBU was classified according to the system of Kimura et al.1 as type BP when the common bile duct joins the pancreatic duct (Fig. 1) and type PB when the pancreatic duct joins the common bile duct (Fig. 2). We added a third type, long Y (Fig. 3), to describe a long common channel without common bile duct dilatation.5 To determine the normal length of the common channel, we evaluated 58 ERCPs normal in appearance from patients with neonatal hepatitis in group 1 and 44 ERCPs without any anatomic abnormalities in patients from group 2 (ages 1 to 15 years). Only ERCP studies that had sufficient biliary and pancreatic duct opacifiVOLUME 50, NO. 2, 1999
Normal and anomalous pancreaticobiliary union in children and adolescents
M Guelrud, C Morera, M Rodriguez, et al.
Table 1. Age distribution and normal common channel length in children and adolescents Age (yr) Variable No. of patients Length of common channel (mm)* Length of common channel (mm; range) Maximal length of common channel (mm)†
<1
1–3
4–6
7–9
10–12
13–15
58 1.86 ± 0.61 1–3 3.0
5 2.2 ± 0.47 1.7–2.8 3.1
12 2.86 ± 0.40 2.2–3.5 3.6
7 3.28 ± 0.43 2.1–3.8 4.1
8 3.96 ± 0.22 3.6–4.3 4.4
12 4.0 ± 0.51 3.1–4.5 5.0
*Mean ± SD. †Mean plus 2 SDM.
cation were analyzed. Common channel length was considered abnormal if values exceeded the mean plus 2 SD of normal. Qualitative values are shown as percentages; quantitative values are presented as mean ± SD. Comparisons were done with a chi-square or Fisher’s exact test when indicated.
RESULTS We performed ERCP on 264 consecutive patients. Group 1 included 136 patients for whom the study was performed to investigate cholestasis. Group 2 included 128 patients with indications of intermittent jaundice (64 patients), or recurrent pancreatitis (64 patients), or both. Table 1 shows the age distribution and the normal length of the common channel. In group 1 the mean length of the common channel was 1.8 ± 0.61 mm (1.0 to 3.0 mm). The length of the common channel increased with age to reach a plateau of 3.9 to 4.0 mm in the 10 to 12 and 13 to 15 year age ranges. For comparison with these data, abnormal values of common channel length were obtained. The maximal length of the common channel in neonates and young children younger than 1 year was 3.0 mm. In children between 10 and 12 years it was 4.4 mm, and in adolescents between 13 and 15 years it was 5 mm. In all patients with APBU from both groups the value for the common channel exceeded these values (Table 2). The difference in length of the common channel between patients with a normal union and those with APBU was highly significant (p < 0.001) in both groups. There were no differences in length of the common channel in patients with choledochal cyst presenting as biliary disease (16.2 ± 5.2 mm) and those presenting with recurrent pancreatitis (15.5 ± 6.5 mm). However, children between 1 and 3 years of age had shorter channels (11.3 ± 5.6 mm) than children between 4 and 12 years of age (17.1 ± 5.0 mm) (p < 0.01). APBU was found in 66 (22.4%) patients. The incidence of APBU in group 1 was 4.4% (6/136) and in group 2 was 46.9% (60/128). Table 3 shows the diseases associated with APBU in patients from group 1. APBU was present in 1.3% (1/76) of patients with neonatal hepatitis (patients with cholestasis defined VOLUME 50, NO. 2, 1999
Table 2. Length of the anomalous pancreaticobiliary union in children and adolescents Variable
Group 1
Group 2
No. of patients Length (mm; mean ± SD) Range (mm)
6 6.9 ± 1.8 4.9–9.1
60 16.0 ± 5.6 6–32
Table 3. Diseases associated with APBU in 136 patients from group 1. Condition Neonatal hepatitis Biliary atresia Choledochal cyst Alagille and paucity syndrome Bile plug syndrome Common bile duct stones Congenital hepatic fibrosis Caroli’s disease and syndrome Primary sclerosing cholangitis Total
No. of patients
No. of patients with APBU
76 44 2 4 4 3 1 1 1 136
1 (1.3%) 3 (6.8%) 2 (100%) 0 0 0 0 0 0 6 (4.4%)
by biochemical criteria without anatomic or mechanical cause), in 6.8% (3/44) of patients with biliary atresia, and in 100% (2/2) of patients with choledochal cyst. Table 4 shows the biliary diseases associated with APBU in group 2. APBU was found in 65.6% (42/64) of these patients. Choledochal cyst was the only biliary disease associated with APBU. Table 5 shows the pancreatic diseases associated with APBU in group 2. The anomaly was found in 28.1% (18/64) of patients. All patients with choledochal cyst (15/15) and 15.7% (3/19) of patients with idiopathic recurrent pancreatitis had an APBU. Table 6 shows the distribution of the different types of APBU in the 60 patients from group 2 who had the anomaly. There was a higher incidence (p = 0.01) of BP type among patients with biliary disease (76%, 32/42) compared with patients with pancreatic diseases (33%, 6/18). Conversely, among patients with pancreatic disease the incidence of the PB type was higher (50%, 9/18) than among patients with biliary disease (24%, 10/42) (p = 0.01). All patients with the long Y type had recurrent pancreatitis. GASTROINTESTINAL ENDOSCOPY
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Table 4. Biliary diseases associated with APBU in 64 patients from group 2 Condition Choledochal cyst Choledocholithiasis Primary sclerosing cholangitis Biliary obstruction (ascaris) Biliary strictures Total
No. of patients
No. of patients with APBU
42 11 5 4 2 64
42 (100%) 0 0 0 0 42 (65.6%)
Table 5. Pancreatic diseases associated with APBU in 64 patients from group 2 Condition Recurrent pancreatitis Choledochal cyst Pancreatocele Short pancreas Ascaris in common bile duct or pancreas Sphincter of Oddi dysfunction Pancreatic pseudocyst Idiopathic condition Chronic pancreatitis Total
No. of patients
No. of patients with APBU
15 1 1 3
15 (100%) 0 0 0
4 3 19 18 64
0 0 3 (15.7%) 0 18 (28.1%)
In group 1 minor clinically insignificant complications occurred in 22 patients. Two neonates had transient narcotic-induced respiratory depression, and two infants had non-narcotic respiratory depression, which resolved spontaneously during support with supplemental oxygen. In 17 patients, minor acute duodenal erosions were found but did not have clinical consequences. One neonate had abdominal distention for 10 hours after ERCP, and it resolved without treatment. In group 2 one patient had cholangitis and one had mild pancreatitis. DISCUSSION The normal length of the common channel in children is not known. In a necropsy study of 35 infants younger than 12 months without biliopancreatic disease, the common channel was shorter than 2 mm in all cases with an average length of 1.3 mm.6 In our study the mean length of the normal common channel in neonates and infants younger than 1 year was 1.8 ± 0.6 mm. In children older than 1 year the length of the common channel increases with age. A common channel longer than 3 mm in neonates and young infants should be considered abnormal. This conclusion holds for children 1 to 3 years of age. However, among children 4 and 9 years of age the maximal length of the common channel is 4 mm, and among children and adolescents between 192
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Table 6. Incidence of the different types of APBU in 60 patients from group 2 Condition Biliary disease Pancreatic disease Total
No. of patients with APBU 42 18 60
BP
Type of APBU PB Long Y
32 6 38 (63%)
10 9 19 (32%)
0 3 3 (5%)
10 and 15 years of age it is 5 mm. In group 1 and group 2 in our study, the difference between normal common channel length and abnormal length was statistically significant. The smallest abnormal value in both groups was higher than the mean plus two standard deviations for the normal values and higher than the highest value within the range of normal for the length of the common channel. The prevalence of APBU in infancy has not been established. Because APBU is a congenital anomaly, its prevalence in the pediatric population should be the same as that for the adult population. We found that its prevalence among neonates and young infants without pancreatic diseases was 4.4% (Table 2), which is similar to that reported for the adult population (1.5% to 3.2%).1,2,7,8 The incidence of APBU increased when older patients with biliary and pancreatic disorders were included. Among patients with intermittent jaundice it was 65% (Table 4). All these patients had choledochal cyst, a disorder characterized by the presence of APBU in almost all cases.1 Among patients with recurrent pancreatitis the incidence was 28% (Table 5). Choledochal cyst was present in all but three patients with APBU without bile duct dilatation. This high incidence of APBU among children can be explained by the fact that our hospital is a tertiary center that specializes in pediatric ERCP. In this study, children older than 1 year with biliary disease and choledochal cyst had a higher incidence of type BP APBU than children with recurrent pancreatitis and choledochal cyst, who had a higher incidence of the PB type. It seems that recurrent pancreatitis is more directly associated with the PB type than the BP type. This finding is similar to that in a report from Japan.9 Three patients with recurrent pancreatitis had a long Y type APBU without choledochal cyst. This finding suggests that in some patients with recurrent pancreatitis the presence of an APBU is more important as an etiologic factor than is the choledochal cyst. We do not have a clear explanation for this finding. One possibility is that drainage of the pancreatic duct is impaired as a result of functional obstruction at the sphincter of Oddi.10-12 The second possibility is that reflux of common bile duct secretions into the panVOLUME 50, NO. 2, 1999
Normal and anomalous pancreaticobiliary union in children and adolescents
creatic duct through the APBU leads to activation of pancreatic enzymes.7,9,13 Because of the high incidence of gallbladder and bile duct carcinoma in patients with APBU and choledochal cyst,1,8,14,15 these children should have the cyst resected and they should be followed closely during their adult life. When recurrent pancreatitis is associated with this anomaly, endoscopic sphincterotomy or surgical sphincteroplasty should be added to cyst resection to avoid more damage to the pancreas. REFERENCES 1. Kimura K, Ohto M, Saisho H, Unozawa T, Tsuchiya Y, Morita M, et al. Association of gallbladder carcinoma and anomalous pancreaticobiliary ductal union. Gastroenterology 1985;89: 1258-65. 2. Misra SP, Gulati P, Thorat VK, Vij JC, Anand BS. Pancreaticobiliary ductal union in biliary diseases: an endoscopic retrograde cholangiopancreatography study. Gastroenterology 1989;96:907-12. 3. Ono J, Sakoda K, Akita H. Surgical aspects of cystic dilatation of the bile duct: an anomalous junction of the pancreaticobiliary tract in adults. Ann Surg 1982;195:203-8. 4. Guelrud M, Jaen D, Mendoza S, Plaz J, Torres P. ERCP in the diagnosis of extrahepatic biliary atresia. Gastrointest Endosc 1991;37:522-6. 5. Guelrud M, Carr-Locke DL, Fox VL. ERCP in pediatric practice: diagnosis and treatment. Oxford: Isis Medical Media; 1997.
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6. Miyano T, Suruga K, Suda K. Abnormal choledocho-pancreatico ductal junction related to the etiology of infantile obstructive jaundice diseases. J Pediatr Surg 1979;14:16-26. 7. Kato O, Hattori K, Suzuki T, Tachino F, Yuasa T. Clinical significance of anomalous pancreaticobiliary union. Gastrointest Endosc 1983;29:94-8. 8. Yamauchi S, Koga A, Matsumoto S, Tanaka M, Nakayama F. Anomalous junction of pancreaticobiliary duct without congenital choledochal cyst: a possible risk factor for gallbladder cancer. Am J Gastroenterol 1987;82:20-4. 9. Mori K, Nagakawa T, Ohta T, Nakano T, Kadoya N, Kayahara M, et al. Acute pancreatitis associated with anomalous union of the pancreaticobiliary ductal system. J Clin Gastroenterol 1991;13:673-7. 10. Ponce J, Garrigues V, Sala T, Pertejo V, Berenger J. Endoscopic biliary manometry in patients with suspected sphincter of Oddi dysfunction and in patients with cystic dilatation of the bile ducts. Dig Dis Sci 1989;34:367-71. 11. Matsumoto S, Tanaka M, Ikeda S, Yoshimoto H. Sphincter of Oddi motor activity in patients with anomalous pancreaticobiliary junction. Am J Gastroenterol 1991;81:831-4. 12. Guelrud M, Morera C, Rodriguez M, Jaen D. Sphincter of Oddi dysfunction in children with recurrent pancreatitis and choledochal cyst [abstract]. Gastrointest Endosc 1997;45:143. 13. Mohan P, Holocomb GW, Ziegler MM. Recurrent jaundice and pancreatitis in a child with pancreaticobiliary duct anomalies. J Pediatr Gastroenterol Nutr 1994;18:386-90. 14. Todani T, Tabuchi K, Watanabe Y, Kobayashi T. Carcinoma arising in the wall of congenital bile duct cysts. Cancer 1979;44:1134-41. 15. Yoshida H, Itai Y, Minami M. Biliary malignancies occurring in choledochal cysts. Radiology 1989;173:389-92.
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Background: The normal length of the pancreaticobiliary union (common channel) in the pediatric population is not known, nor is the frequency of anomalous pancreaticobiliary union and the extent to which it is associated with pancreaticobiliary disease. Methods: ERCP was performed on 136 patients younger than 1 year (group 1) and 128 older than 1 year (group 2). Results: In group 1 the average length of the common channel was 1.8 ± 0.61 mm with a maximal length of 3 mm (mean plus 2 standard deviations). In group 2 the average length and maximal length of the common channel increased with age. In the 1 to 3 year age range the average length was 2.2 ± 0.47 mm with a maximal length of 2.7 mm, in the 4 to 6 year range it was 2.8 ± 0.40 mm (3.6 mm maximal), in the 7 to 9 year range it was 3.2 ± 0.43 mm (4.1 mm maximal), in the 10 to 12 year range it was 3.9 ± 0.5 mm (4.4 mm maximal), and in the 13 to 15 year range it was 4.0 ± 0.51 mm (5 mm maximal). The prevalence of the anomalous pancreaticobiliary union was 25% (66/264). In group 1 the anomaly was present in 4.4% (6 of 136) of patients, 1.3% (1/76) with neonatal hepatitis, 4.6% (3/44) with biliary atresia, and 100% (2/2) with choledochal cyst. In group 2 the anomaly was present in 46.9% (60/128) of patients, 100% (57/57) with choledochal cyst and 15.7% (3/19) with idiopathic recurrent pancreatitis without bile duct dilatation. Conclusions: The mean length of the common channel increases with age. The maximum normal length of the common channel in neonates and infants younger than 1 year is 3 mm. It increases with age to a maximum of 5 mm in children and adolescents between 13 and 15 years of age. Anomalous pancreaticobiliary union is relatively common among children and adolescents undergoing ERCP in our center, including those with idiopathic recurrent pancreatitis (15.7%). ERCP is valuable in the diagnosis of this anomaly. (Gastrointest Endosc 1999;50:189-93.)
Anomalous pancreaticobiliary union (ABPU) is a congenital malformation of the pancreaticobiliary tree in which the confluence of the common bile duct and pancreatic duct is outside the duodenal wall. A common channel for bile and pancreatic secretion ordinarily is formed by the absence of the septum between the biliary and pancreatic ducts as they approach the ampulla of Vater. In adults, the normal length of the common channel at ERCP is 4.5 mm with a range of 1 to 12 mm.1,2 APBU is considered to be present when the common channel as demonstrated with ERCP measures more than 15 mm1 or when its extraduodenal portion is more than 6 mm long.3 However, these measurements cannot be applied to the pediatric population. In this study we established the normal length of the common channel in pediatric and adolescent
Received April 29, 1998. For revision August 27, 1998. Accepted January 14, 1999. From the Gastroenterology Department and Pediatric Gastroenterology Unit, Hospital General del Oeste, Caracas Venezuela. Reprint requests: Moises Guelrud, MD, Policlínica Metropolitana, Urb. Caurimare, Calle A1, Caracas 1060, Venezuela. Copyright © 1999 by the American Society for Gastrointestinal Endoscopy 0016-5107/99/$8.00 + 0 37/1/97113 VOLUME 50, NO. 2, 1999
patients, assessed the frequency of APBU among our patients, and examined the association between this anomaly and pancreaticobiliary disease. PATIENTS AND METHODS We retrospectively reviewed 264 consecutive ERCP studies performed during the last 12 years on pediatric patients with suspected pancreaticobiliary disease. The patients were classified into two age groups. Group 1 included neonates and infants younger than 1 year for whom ERCP was performed to evaluate neonatal cholestasis. Group 2 included patients between 1 and 19 years of age in whom ERCP was performed to evaluate intermittent jaundice or recurrent pancreatitis. For children younger than 3 years ERCP was performed with pediatric duodenoscopes (Prototype PJF with an external diameter of 8.5 mm and the standard PJF with an external diameter of 7.5 mm; Olympus America, Inc., Melville, N.Y.). For older children a standard duodenoscope (JF-1T; Olympus) was used. For 34 infants older than 3 months in group 1 and for all patients in group 2 the procedure was performed with conscious sedation with a combination of meperidine (2 to 4 mg/kg, maximum 100 mg) administered intravenously with diazepam (0.1 to 0.3 mg/kg, maximum 15 mg) or midazolam (0.1 to 0.3 mg/kg, maximum 15 mg). General anesthesia was used for 6 neonates. Continuous monitoring of heart rate GASTROINTESTINAL ENDOSCOPY
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Figure 3. ERCP shows anomalous pancreaticobiliary union of type long Y without common bile duct dilatation in a 30day-old neonate with biliary atresia. Figure 1. ERCP shows anomalous pancreaticobiliary union of type BP in a 12-year-old girl with choledochal cyst.
Figure 2. ERCP shows anomalous pancreaticobiliary union of type PB in a 4-year-old girl with choledochal cyst. 190
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and capillary oxygen saturation was maintained during ERCP and during the postprocedural period until full recovery was achieved. All procedures were performed on an ambulatory basis. Patients were discharged in 2 to 4 hours, and guardians were instructed in recognition of signs and symptoms of complications and the procedure for obtaining medical assistance. A 5F ERCP catheter was used, and to achieve good visualization of the common channel the papilla was cannulated just at its tip. Four to six radiographs were available for each patient. Only ERCP studies in which the terminal common channel was clearly opacified were evaluated. To account for magnification, the distal end of the duodenoscope was measured, and the measurement of the length of the common channel was adjusted accordingly. Patients with ERCP findings of pancreas divisum, annular pancreas, and biliary atresia type 14 in which there was no visualization of the biliary duct were excluded. Among patients with insufficient pancreatic duct visualization, the absence of an incidental pancreas divisum or annular pancreas could not be determined. APBU was classified according to the system of Kimura et al.1 as type BP when the common bile duct joins the pancreatic duct (Fig. 1) and type PB when the pancreatic duct joins the common bile duct (Fig. 2). We added a third type, long Y (Fig. 3), to describe a long common channel without common bile duct dilatation.5 To determine the normal length of the common channel, we evaluated 58 ERCPs normal in appearance from patients with neonatal hepatitis in group 1 and 44 ERCPs without any anatomic abnormalities in patients from group 2 (ages 1 to 15 years). Only ERCP studies that had sufficient biliary and pancreatic duct opacifiVOLUME 50, NO. 2, 1999
Normal and anomalous pancreaticobiliary union in children and adolescents
M Guelrud, C Morera, M Rodriguez, et al.
Table 1. Age distribution and normal common channel length in children and adolescents Age (yr) Variable No. of patients Length of common channel (mm)* Length of common channel (mm; range) Maximal length of common channel (mm)†
<1
1–3
4–6
7–9
10–12
13–15
58 1.86 ± 0.61 1–3 3.0
5 2.2 ± 0.47 1.7–2.8 3.1
12 2.86 ± 0.40 2.2–3.5 3.6
7 3.28 ± 0.43 2.1–3.8 4.1
8 3.96 ± 0.22 3.6–4.3 4.4
12 4.0 ± 0.51 3.1–4.5 5.0
*Mean ± SD. †Mean plus 2 SDM.
cation were analyzed. Common channel length was considered abnormal if values exceeded the mean plus 2 SD of normal. Qualitative values are shown as percentages; quantitative values are presented as mean ± SD. Comparisons were done with a chi-square or Fisher’s exact test when indicated.
RESULTS We performed ERCP on 264 consecutive patients. Group 1 included 136 patients for whom the study was performed to investigate cholestasis. Group 2 included 128 patients with indications of intermittent jaundice (64 patients), or recurrent pancreatitis (64 patients), or both. Table 1 shows the age distribution and the normal length of the common channel. In group 1 the mean length of the common channel was 1.8 ± 0.61 mm (1.0 to 3.0 mm). The length of the common channel increased with age to reach a plateau of 3.9 to 4.0 mm in the 10 to 12 and 13 to 15 year age ranges. For comparison with these data, abnormal values of common channel length were obtained. The maximal length of the common channel in neonates and young children younger than 1 year was 3.0 mm. In children between 10 and 12 years it was 4.4 mm, and in adolescents between 13 and 15 years it was 5 mm. In all patients with APBU from both groups the value for the common channel exceeded these values (Table 2). The difference in length of the common channel between patients with a normal union and those with APBU was highly significant (p < 0.001) in both groups. There were no differences in length of the common channel in patients with choledochal cyst presenting as biliary disease (16.2 ± 5.2 mm) and those presenting with recurrent pancreatitis (15.5 ± 6.5 mm). However, children between 1 and 3 years of age had shorter channels (11.3 ± 5.6 mm) than children between 4 and 12 years of age (17.1 ± 5.0 mm) (p < 0.01). APBU was found in 66 (22.4%) patients. The incidence of APBU in group 1 was 4.4% (6/136) and in group 2 was 46.9% (60/128). Table 3 shows the diseases associated with APBU in patients from group 1. APBU was present in 1.3% (1/76) of patients with neonatal hepatitis (patients with cholestasis defined VOLUME 50, NO. 2, 1999
Table 2. Length of the anomalous pancreaticobiliary union in children and adolescents Variable
Group 1
Group 2
No. of patients Length (mm; mean ± SD) Range (mm)
6 6.9 ± 1.8 4.9–9.1
60 16.0 ± 5.6 6–32
Table 3. Diseases associated with APBU in 136 patients from group 1. Condition Neonatal hepatitis Biliary atresia Choledochal cyst Alagille and paucity syndrome Bile plug syndrome Common bile duct stones Congenital hepatic fibrosis Caroli’s disease and syndrome Primary sclerosing cholangitis Total
No. of patients
No. of patients with APBU
76 44 2 4 4 3 1 1 1 136
1 (1.3%) 3 (6.8%) 2 (100%) 0 0 0 0 0 0 6 (4.4%)
by biochemical criteria without anatomic or mechanical cause), in 6.8% (3/44) of patients with biliary atresia, and in 100% (2/2) of patients with choledochal cyst. Table 4 shows the biliary diseases associated with APBU in group 2. APBU was found in 65.6% (42/64) of these patients. Choledochal cyst was the only biliary disease associated with APBU. Table 5 shows the pancreatic diseases associated with APBU in group 2. The anomaly was found in 28.1% (18/64) of patients. All patients with choledochal cyst (15/15) and 15.7% (3/19) of patients with idiopathic recurrent pancreatitis had an APBU. Table 6 shows the distribution of the different types of APBU in the 60 patients from group 2 who had the anomaly. There was a higher incidence (p = 0.01) of BP type among patients with biliary disease (76%, 32/42) compared with patients with pancreatic diseases (33%, 6/18). Conversely, among patients with pancreatic disease the incidence of the PB type was higher (50%, 9/18) than among patients with biliary disease (24%, 10/42) (p = 0.01). All patients with the long Y type had recurrent pancreatitis. GASTROINTESTINAL ENDOSCOPY
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Table 4. Biliary diseases associated with APBU in 64 patients from group 2 Condition Choledochal cyst Choledocholithiasis Primary sclerosing cholangitis Biliary obstruction (ascaris) Biliary strictures Total
No. of patients
No. of patients with APBU
42 11 5 4 2 64
42 (100%) 0 0 0 0 42 (65.6%)
Table 5. Pancreatic diseases associated with APBU in 64 patients from group 2 Condition Recurrent pancreatitis Choledochal cyst Pancreatocele Short pancreas Ascaris in common bile duct or pancreas Sphincter of Oddi dysfunction Pancreatic pseudocyst Idiopathic condition Chronic pancreatitis Total
No. of patients
No. of patients with APBU
15 1 1 3
15 (100%) 0 0 0
4 3 19 18 64
0 0 3 (15.7%) 0 18 (28.1%)
In group 1 minor clinically insignificant complications occurred in 22 patients. Two neonates had transient narcotic-induced respiratory depression, and two infants had non-narcotic respiratory depression, which resolved spontaneously during support with supplemental oxygen. In 17 patients, minor acute duodenal erosions were found but did not have clinical consequences. One neonate had abdominal distention for 10 hours after ERCP, and it resolved without treatment. In group 2 one patient had cholangitis and one had mild pancreatitis. DISCUSSION The normal length of the common channel in children is not known. In a necropsy study of 35 infants younger than 12 months without biliopancreatic disease, the common channel was shorter than 2 mm in all cases with an average length of 1.3 mm.6 In our study the mean length of the normal common channel in neonates and infants younger than 1 year was 1.8 ± 0.6 mm. In children older than 1 year the length of the common channel increases with age. A common channel longer than 3 mm in neonates and young infants should be considered abnormal. This conclusion holds for children 1 to 3 years of age. However, among children 4 and 9 years of age the maximal length of the common channel is 4 mm, and among children and adolescents between 192
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Table 6. Incidence of the different types of APBU in 60 patients from group 2 Condition Biliary disease Pancreatic disease Total
No. of patients with APBU 42 18 60
BP
Type of APBU PB Long Y
32 6 38 (63%)
10 9 19 (32%)
0 3 3 (5%)
10 and 15 years of age it is 5 mm. In group 1 and group 2 in our study, the difference between normal common channel length and abnormal length was statistically significant. The smallest abnormal value in both groups was higher than the mean plus two standard deviations for the normal values and higher than the highest value within the range of normal for the length of the common channel. The prevalence of APBU in infancy has not been established. Because APBU is a congenital anomaly, its prevalence in the pediatric population should be the same as that for the adult population. We found that its prevalence among neonates and young infants without pancreatic diseases was 4.4% (Table 2), which is similar to that reported for the adult population (1.5% to 3.2%).1,2,7,8 The incidence of APBU increased when older patients with biliary and pancreatic disorders were included. Among patients with intermittent jaundice it was 65% (Table 4). All these patients had choledochal cyst, a disorder characterized by the presence of APBU in almost all cases.1 Among patients with recurrent pancreatitis the incidence was 28% (Table 5). Choledochal cyst was present in all but three patients with APBU without bile duct dilatation. This high incidence of APBU among children can be explained by the fact that our hospital is a tertiary center that specializes in pediatric ERCP. In this study, children older than 1 year with biliary disease and choledochal cyst had a higher incidence of type BP APBU than children with recurrent pancreatitis and choledochal cyst, who had a higher incidence of the PB type. It seems that recurrent pancreatitis is more directly associated with the PB type than the BP type. This finding is similar to that in a report from Japan.9 Three patients with recurrent pancreatitis had a long Y type APBU without choledochal cyst. This finding suggests that in some patients with recurrent pancreatitis the presence of an APBU is more important as an etiologic factor than is the choledochal cyst. We do not have a clear explanation for this finding. One possibility is that drainage of the pancreatic duct is impaired as a result of functional obstruction at the sphincter of Oddi.10-12 The second possibility is that reflux of common bile duct secretions into the panVOLUME 50, NO. 2, 1999
Normal and anomalous pancreaticobiliary union in children and adolescents
creatic duct through the APBU leads to activation of pancreatic enzymes.7,9,13 Because of the high incidence of gallbladder and bile duct carcinoma in patients with APBU and choledochal cyst,1,8,14,15 these children should have the cyst resected and they should be followed closely during their adult life. When recurrent pancreatitis is associated with this anomaly, endoscopic sphincterotomy or surgical sphincteroplasty should be added to cyst resection to avoid more damage to the pancreas. REFERENCES 1. Kimura K, Ohto M, Saisho H, Unozawa T, Tsuchiya Y, Morita M, et al. Association of gallbladder carcinoma and anomalous pancreaticobiliary ductal union. Gastroenterology 1985;89: 1258-65. 2. Misra SP, Gulati P, Thorat VK, Vij JC, Anand BS. Pancreaticobiliary ductal union in biliary diseases: an endoscopic retrograde cholangiopancreatography study. Gastroenterology 1989;96:907-12. 3. Ono J, Sakoda K, Akita H. Surgical aspects of cystic dilatation of the bile duct: an anomalous junction of the pancreaticobiliary tract in adults. Ann Surg 1982;195:203-8. 4. Guelrud M, Jaen D, Mendoza S, Plaz J, Torres P. ERCP in the diagnosis of extrahepatic biliary atresia. Gastrointest Endosc 1991;37:522-6. 5. Guelrud M, Carr-Locke DL, Fox VL. ERCP in pediatric practice: diagnosis and treatment. Oxford: Isis Medical Media; 1997.
M Guelrud, C Morera, M Rodriguez, et al.
6. Miyano T, Suruga K, Suda K. Abnormal choledocho-pancreatico ductal junction related to the etiology of infantile obstructive jaundice diseases. J Pediatr Surg 1979;14:16-26. 7. Kato O, Hattori K, Suzuki T, Tachino F, Yuasa T. Clinical significance of anomalous pancreaticobiliary union. Gastrointest Endosc 1983;29:94-8. 8. Yamauchi S, Koga A, Matsumoto S, Tanaka M, Nakayama F. Anomalous junction of pancreaticobiliary duct without congenital choledochal cyst: a possible risk factor for gallbladder cancer. Am J Gastroenterol 1987;82:20-4. 9. Mori K, Nagakawa T, Ohta T, Nakano T, Kadoya N, Kayahara M, et al. Acute pancreatitis associated with anomalous union of the pancreaticobiliary ductal system. J Clin Gastroenterol 1991;13:673-7. 10. Ponce J, Garrigues V, Sala T, Pertejo V, Berenger J. Endoscopic biliary manometry in patients with suspected sphincter of Oddi dysfunction and in patients with cystic dilatation of the bile ducts. Dig Dis Sci 1989;34:367-71. 11. Matsumoto S, Tanaka M, Ikeda S, Yoshimoto H. Sphincter of Oddi motor activity in patients with anomalous pancreaticobiliary junction. Am J Gastroenterol 1991;81:831-4. 12. Guelrud M, Morera C, Rodriguez M, Jaen D. Sphincter of Oddi dysfunction in children with recurrent pancreatitis and choledochal cyst [abstract]. Gastrointest Endosc 1997;45:143. 13. Mohan P, Holocomb GW, Ziegler MM. Recurrent jaundice and pancreatitis in a child with pancreaticobiliary duct anomalies. J Pediatr Gastroenterol Nutr 1994;18:386-90. 14. Todani T, Tabuchi K, Watanabe Y, Kobayashi T. Carcinoma arising in the wall of congenital bile duct cysts. Cancer 1979;44:1134-41. 15. Yoshida H, Itai Y, Minami M. Biliary malignancies occurring in choledochal cysts. Radiology 1989;173:389-92.
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