Endoscopic retrograde cholangiography in the diagnosis of biliary malformations in infants

Management options for cholestatic liver disease in children

Due to a peculiar age-dependent increased susceptibility, neonatal cholestasis affects the liver of approximately 1 in every 2500 term infants. A high index of suspicion is the key to an early diagnosis, and to implement timely, often life-saving treatments. Even when specific treatment is not available or curative, prompt medical management and optimization of nutrition are of paramount importance to survival and avoidance of complications. Areas covered: The present article will prominently focus on a series of newer diagnostic and therapeutic options of cholestasis in neonates and infants blended with consolidated established paradigms. The overview of strategies for the management reported here is based on a systematic literature search published in English using accessible databases (PubMed, MEDLINE) with the keywords biliary atresia, choleretics and neonatal cholestasis. References lists from retrieved articles were also reviewed. Expert commentary: A large number of uncommon and rare hepatobiliary disorders may present with cholestasis during the neonatal and infantile period. Potentially life-saving disease-specific pharmacological and surgical therapeutic approaches are currently available. Advances in hepatobiliary transport mechanisms have started clarifying fundamental aspects of inherited and acquired cholestasis, laying the foundation for the development of possibly more effective specific therapies.

Evaluation of the use of laparoscopic-guided cholecystocholangiography and liver biopsy in definitive diagnosis of neonatal cholestatic jaundice

BACKGROUND

Once it is established that a jaundiced infant has direct hyperbilirubinemia, the principal diagnostic concern is to differentiate hepatocellular from obstructive cholestasis. Traditional tests such as ultrasonography, percutaneous liver biopsy and technetium 99 m hepatobiliary iminodiacetic acid (HIDA) scan are often not sufficiently discriminating. Definitive exclusion of biliary atresia (BA) in the infant with cholestatic jaundice usually requires mini-laparotomy and intra-operative cholangiography. This approach has many drawbacks because those sick infants are subjected to a time-consuming procedure with the probability of negative surgical exploration.

AIM OF THE STUDY

The aim of this study was to determine the feasibility of laparoscopic-guided cholecystocholangiography (LGCC) and its accuracy and safety in the diagnosis of BA and thus preventing unnecessary laparotomy in infants whose cholestasis is caused by diseases other than BA.

PATIENTS AND METHODS

Twelve cholestatic infants with direct hyperbilirubinemia subjected to LGCC (age, 7-98 days; mean, 56 days) after ultrasound scan and (99 mTc) HIDA scan and percutaneous liver biopsy failed to provide the definitive diagnosis.

RESULTS

One patient had completely absent gall bladder (GB) so the laparoscopic procedure was terminated and laparotomy was done (Kasai operation). Four patients had small size GB; they underwent LGCC that showed patent common bile duct with atresia of common hepatic duct, so laparotomy and Kasai operation was performed. Seven patients had well-developed GB, LGCC revealed patent biliary tree, so laparoscopic liver biopsies were taken for histopathology. Five of those patients had neonatal hepatitis, and two had cholestasis as a complication of prolonged TPN. No perioperative complications or mortalities were recorded.

CONCLUSION

When the diagnosis neonatal cholestasis remains elusive after traditional investigations, LGCC is an accurate and simple method for differentiating BA from hepatocellular causes.

Systemerkrankungen

Systemerkrankungen als Ursache einer Lebererkrankung sind häufig, ohne dass man genaue Zahlen angeben kann. Die verschiedenen Grunderkrankungen sind für sich betrachtet zwar selten, nur dadurch, dass viele Erkrankungen in Betracht gezogen werden müssen, ergibt sich eine relative Häufung. Durch Fortschritte auf dem Gebiet der molekularbiologischen Diagnostik insbesondere bei den Stoffwechselerkrankungen lassen sich heute bereits viele der in Frage kommenden Grunderkrankungen eindeutig nachweisen. Allerdings ist bei keiner der Erkrankungen ein hundertprozentiger molekularbiologischer Nachweis möglich. Damit ergibt sich eine sichere Diagnose nur bei einem positiven Nachweis. Bei fehlendem Nachweis einer bisher bekannten für die Erkrankung spezifischen Mutation bleibt die Zuordnung entweder enzymatischen Tests oder klinischer Diagnose vorbehalten. Insbesondere bei der Manifestation als akutes Leberversagen ist die für die Diagnosesicherung erforderliche Zeit damit oft nicht vorhanden.

HIDA, percutaneous transhepatic cholecysto-cholangiography and liver biopsy in infants with persistent jaundice: can a combination of PTCC and liver biopsy reduce unnecessary laparotomy?

BACKGROUND

Historically, HIDA is the initial diagnostic test in the evaluation of biliary atresia (BA). Non-excreting HIDA scans can yield false-positive results leading to negative laparotomy.

OBJECTIVE

Cholestatic infants must be evaluated promptly to exclude biliary atresia (BA) and other treatable hepatic conditions. Intraoperative cholangiogram (IOC) is the gold standard for diagnosing BA, but requires surgical intervention. Percutaneous transhepatic cholecysto-cholangiography (PTCC) and liver biopsy are less invasive and have been described in small case series. We hypothesized that PTCC and liver biopsy effectively exclude BA, thus avoiding unnecessary IOC.

MATERIALS AND METHODS

Retrospective review of cholestatic infants who underwent PTCC, biopsy or cholescintigraphy at a tertiary children's hospital from August 1998 to January 2009. Group differences were evaluated and the receiver operator curve and safety of PTCC determined.

RESULTS

One-hundred twenty-eight cholestatic infants were reviewed. Forty-six (36%) underwent PTCC. Forty-one out of 46 (89%) had simultaneous PTCC and liver biopsy. PTCC was completed successfully in 19/23 (83%) children despite a small or absent GB on initial US. Negative laparotomy rate was 1/6 (17%) for simultaneous PTCC/liver biopsy. Complications occurred in 4/46 including bleeding (n=2), fever with elevated transaminases (n=1) and oxygen desaturations (n=1).

CONCLUSION

PTCC, particularly when performed in combination with simultaneous liver biopsy, effectively excludes BA in cholestatic infants with acceptable morbidity. PTCC can frequently be performed when a contracted gallbladder is seen on initial US exam. Negative laparotomy rate is lowest when PTCC is coupled with simultaneous liver biopsy.

Comparison of different diagnostic methods for differentiating biliary atresia from idiopathic neonatal hepatitis

AIM

To retrospectively analyze different methods in differentiating biliary atresia from idiopathic neonatal hepatitis.

METHODS

Sixty-nine infants with cholestatic jaundice and final diagnosis of idiopathic neonatal hepatitis (INH) and biliary atresia (BA) were studied retroprospectively from January 2004 to December 2006. A thorough history and physical examination were undertaken. All cases underwent abdominal magnetic resonance cholangiography (MRCP), ultrasonography (US), hepatobiliary scintigraphy (HBS), HBS single-photon emission computer tomography (HBS SPECT), and operation or percutaneous liver biopsy. The accuracy, sensitivity, specificity, and predictive values of these various methods were compared.

RESULTS

There were 39 girls and 30 boys, among whom 35 had INH (age, 61+/-17 days) and 34 had BA (age, 64+/-18 days). The mean age at onset of jaundice was significantly lower in cases of BA when compared to INH cases (9+/-13 vs. 20+/-21 days; P=.032). The diagnostic accuracy of different methods was as follows: liver biopsy, 97.1%; HBS SPECT, 91.30%; MRCP, 71.01%; HBS, 66.67%; US, 65.22%.

CONCLUSION

Our results indicate that biopsy of the liver is considered as the most reliable method to differentiate INH from BA. The accuracy of HBS SPECT is higher than that of MRCP, HBS, and US. There was no significant difference in diagnostic accuracy among MRCP, HBS, and US.

[Endoscopic retrograde cholangiopancreatography in patients aged less than 18 years old: our experience]

BACKGROUND

There is scant information on the use of endoscopic retrograde cholangiopancreatography (ERCP) in patients under 18.

OBJECTIVE

To analyze our experience in all patients under 18 who underwent ERCP.

PATIENTS AND METHODS

We performed a retrospective study of all ERCP conducted in patients under 18 between 1993 and 2006. We analyzed indications, endoscopic and radiologic findings, diagnostic and therapeutic success, and complications.

RESULTS

We included 31 patients who underwent 36 ERCP in total. The mean age was 9.89 +/- 5 years old. We used general anesthesia in 58.3% (21 patients), with a mean age of 8 +/- 5 years. The most frequent indications were complications after liver transplantation in 33.3% (12 patients), suspicion of biliary obstruction in 27.7% (10 patients), and pancreatitis in 22.2% (8 patients). We achieved cannulation and repletion in the selected duct in 94.4%. The most frequent pathologic findings were changes in the biliary tract after liver transplantation in 25% (9 patients). The results of ERCP were normal in 10 patients (27.7%). Therapeutic maneuvers were indicated in 17 out of the 34 (50%) examinations considered, achieving therapeutic success in 76.47% (13/17). Complications consisted of hemorrhage after simple sphincterotomy in one patient (2.8%) and mild pancreatitis in two patients (5.6%).

CONCLUSIONS

We found ERCP to be a safe procedure with a high diagnostic and therapeutic success rate, and a low rate of early complications.

Guideline for the evaluation of cholestatic jaundice in infants: recommendations of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition

For the primary care provider, cholestatic jaundice in infancy, defined as jaundice caused by an elevated conjugated bilirubin, is an uncommon but potentially serious problem that indicates hepatobiliary dysfunction. Early detection of cholestatic jaundice by the primary care physician and timely, accurate diagnosis by the pediatric gastroenterologist are important for successful treatment and a favorable prognosis. The Cholestasis Guideline Committee of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition has formulated a clinical practice guideline for the diagnostic evaluation of cholestatic jaundice in the infant. The Cholestasis Guideline Committee, consisting of a primary care pediatrician, a clinical epidemiologist (who also practices primary care pediatrics), and five pediatric gastroenterologists, based its recommendations on a comprehensive and systematic review of the medical literature integrated with expert opinion. Consensus was achieved through the Nominal Group Technique, a structured quantitative method. The Committee examined the value of diagnostic tests commonly used for the evaluation of cholestatic jaundice and how those interventions can be applied to clinical situations in the infant. The guideline provides recommendations for management by the primary care provider, indications for consultation by a pediatric gastroenterologist, and recommendations for management by the pediatric gastroenterologist. The Cholestasis Guideline Committee recommends that any infant noted to be jaundiced at 2 weeks of age be evaluated for cholestasis with measurement of total and direct serum bilirubin. However, breast-fed infants who can be reliably monitored and who have an otherwise normal history (no dark urine or light stools) and physical examination may be asked to return at 3 weeks of age and, if jaundice persists, have measurement of total and direct serum bilirubin at that time. This document represents the official recommendations of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition on the evaluation of cholestatic jaundice in infants. The American Academy of Pediatrics has also endorsed these recommendations. These recommendations are a general guideline and are not intended as a substitute for clinical judgment or as a protocol for the care of all patients with this problem.

Percutaneous cholecysto-cholangiography in the diagnosis of obstructive jaundice in infants

BACKGROUND

Once it is established that a jaundiced infant has an elevated direct bilirubin level, the principal diagnostic concern is the differentiation of hepatocellular from obstructive cholestasis, of disorders of physiology from disorders of anatomy, and of disease that is managed medically from disease that is managed surgically. Traditional tests such as ultrasonography, liver biopsy, and technotium 99m HIDA scan are often not sufficiently discriminating. General anesthesia is required for invasive imaging with endoscopic retrograde cholangio pancreatography (ERCP) or operative cholangiogram. The authors describe a facile alternative using percutaneous cholecystocholangiography (PCC) with intravenous sedation.

METHODS

Nine cholestatic infants underwent PCC (age, 27 to 73 days; mean, 44 days) after ultrasoundscan, liver biopsy, and (99mTc)HIDA scan failed to provide a definitive diagnosis.

RESULTS

In the 4 infants without complete biliary filling, we found biliary atresia (3) and biliary hypoplasia (1). The biliary tree was completely opacified in 5 infants with the following diagnosis: neonatal hepatitis (2), duplication of the gallbladder (1), choledochocele (1), total parenteral nutrition (TPN) cholestasis (1). There were no complications.

CONCLUSIONS

When the etiology of cholestasis remains elusive after traditional firstline tests, PCC has proven to be an accurate simple alternative in differentiating obstructive from hepatocellular causes of infantile cholestatic jaundice.

Surgery for biliary atresia

Although the prognosis of biliary atresia has been improved in recent years, particularly in the era of liver transplantation, hepatic portoenterostomy, e.g., the Kasai operation, is still the first line of surgical treatment. Successful hepatic portoenterostomy depends on early diagnosis and operation, adequate operative technique, prevention of postoperative cholangitis, and precise postoperative management. The pathophysiology of the liver and of the intrahepatic bile ducts in this disease is still controversial.

Biliary atresia

Although the prognosis of biliary atresia has been dramatically improved in the era of liver transplantation, the Kasai operation is still the first line of surgical treatment. Successful hepatic portoenterostomy depends on early diagnosis and surgery, adequate surgical technique, prevention of cholangitis, and precise postoperative management.

Biliary atresia. A surgical perspective

The combination of portoenterostomy with subsequent liver transplantation is the treatment of choice for patients with biliary atresia. It is important, however, to attempt to keep the patient's own organ by continuing efforts to achieve the best possible results with portoenterostomy. Additional basic research, perhaps concerning on the role of cytokines and apoptosis in the control of biliary atresia, may provide insight into possible new medical strategies for treating patients with biliary atresia. For example, in addition to portoenterostomy, control of apoptosis at various cellular levels and of bile duct cell proliferation and maturation by manipulation of the growth factors and cytokines may become part of future treatment modalities. Another direction of research should be the control of fibrogenesis, which might be accomplished by blocking TGF-beta 1 and platelet-derived growth factor and by HGF gene therapy. The author's current strategy for surgical treatment for patients with biliary atresia include (1) early diagnosis, including prenatal diagnosis and broader use of mass screening programs, (2) hepatic portoenterostomy, without stoma formation; (3) close postoperative care, especially for prevention of postoperative cholangitis; (4) revision of portoenterostomy only in selected cases; (5) early liver transplantation in patients with absolutely failed portoenterostomy; (6) avoidance of laparotomy for the treatment of esophageal varices and hypersplenism; (7) consideration of exploratory laparotomy or primary liver transplantation for patients with advanced liver disease at the time of referral. The development of new treatment modalities based on the understanding of the pathogenesis of the disease, and especially on the biology of intrahepatic bile ducts and hepatic fibrosis, is essential.

Biliary atresia in neonates and infants: triangular area of high signal intensity in the porta hepatis at T2-weighted MR cholangiography with US and histopathologic correlation

PURPOSE

To correlate a triangular area of high signal intensity in the porta hepatis on T2-weighted magnetic resonance (MR) cholangiograms of biliary atresia with ultrasonographic (US) and histopathologic findings in a portal mass observed during a Kasai procedure.

MATERIALS AND METHODS

Twenty-one consecutive neonates and infants (age range, 13-88 days; mean age, 59 days) with cholestasis underwent US and single-shot MR cholangiography. In 12 patients with biliary atresia diagnosed at histopathologic examination, MR cholangiographic findings in the porta hepatis were correlated with US and histopathologic findings in the portal mass.

RESULTS

At US, eight of the 12 patients had round, linear, or tubular hypoechoic portions within a triangular cord; MR cholangiography revealed a triangular area of high signal intensity confined to the porta hepatis. Histopathologic examination of the portal mass revealed a cystic or cleftlike lesion surrounded by loose myxoid mesenchyme and platelike fetal bile ducts. Neither the large cystic lesion without ductal epithelium nor the small cleftlike lesion with scanty epithelium demonstrated bile staining. Similar areas of high signal intensity were not seen on T2-weighted images in the remaining patients (four with biliary atresia and nine with neonatal hepatitis).

CONCLUSION

In biliary atresia, T2-weighted single-shot MR cholangiography can show a triangular area of high signal intensity in the porta hepatis that may represent cystic dilatation of the fetal bile duct.

Endoscopic retrograde cholangiopancreatography in paediatric patients with biliary disorders

Endoscopic retrograde cholangiopancreatography (ERCP) has long been used in children. The usefulness of ERCP in paediatric patients with various biliary disorders, however, has not been well documented. Thirty-two sessions of ERCP performed in 29 paediatric patients ranging in age from 1 month to 15 years were evaluated. Endoscopic retrograde cholangiopancreatography was to confirm diagnosis or to obtain detailed information about their pancreaticobiliary system. Cannulation was successful in all patients. Opacification of the biliary tracts was also successful in all except for three patients with extrahepatic biliary atresia. Endoscopic retrograde cholangiopancreatography was assessed to be successful in making a differential diagnosis of neonatal hepatitis from extrahepatic biliary atresia, and in having a confirmed diagnosis of anomalous arrangement of the pancreaticobiliary ductal system associated with choledochal cyst. The procedure was also useful for obtaining detailed information on the pancreaticobiliary system in the other children. No accidents occurred during the endoscopic procedures in any of the paediatric patients. When a confirmed diagnosis or detailed information is needed in paediatric patients with biliary disorders, ERCP is a useful and safe technique.

The role of ERCP in biliary atresia

BACKGROUND

It is not easy to discriminate between infantile hepatitis and biliary atresia in spite of several diagnostic tests including laboratory analyses, ultrasound, and hepatobiliary scans. ERCP is the most useful procedure for visualization of the extrahepatic biliary system, but ERCP is still an uncommon procedure in children.

METHODS

ERCP examination was performed in 52 infants with biliary atresia (10 with infantile hepatitis, 5 with congenital biliary dilatation, 3 with paucity of intrahepatic bile duct, 2 with duodenal atresia, and 1 with postoperative jaundice of hepatoblastoma) aged from 8 days to 300 days (mean, 71 days).

RESULTS

ERCP was successful in 47 with biliary atresia, in 9 with infantile hepatitis, and 10 with another disease. Liver biopsy was performed in 1 infant with hepatitis in whom the cannulation failed; in 9 with hepatitis in whom the cannulation was successful, exploratory laparotomy could be avoided. The ERCP findings in 46 patients with biliary atresia (excluding 1 in whom evaluation could not be performed because of poor x-ray quality) were classified into four patterns.

CONCLUSIONS

A success rate of ERCP examinations in infants was 88%, so ERCP is recommended to make a correct decision regarding the need for surgery in cholestatic disorders.

Endoscopic retrograde cholangiopancreatography (ERCP) in biliary tract disease of infants less than one year old

We performed a total of 75 examinations with endoscopic retrograde chlangiopancreatography (ERCP) in 73 infants aged from 8 days to 300 days (mean 71 days) between 1977 and 1995. ERCP examination was performed with a prototype duodenoscope and was successful in 47 of 52 examinations in biliary atresia, 9 of 11 in neonatal hepatitis, all 4 in paucity of intra-hepatic bile duct, 4 of 5 in congenital biliary dilatation, 1 of 2 in duodenal stricture, and 1 case of in postoperative jaundice of hepatoblastoma. In 46 infants with biliary atresia, excluding one in whom the findings could not be evaluated due to poor x-ray image quality, we distinguished the following four patterns of ERCP findings: Pattern 1, only the pancreatic duct could be demonstrated and no bile duct was visualized (76%); Pattern 2, only a part of the distal common bile duct with the pancreatic duct was visualized (2%); Pattern 3, the entire length of the common bile duct with the pancreatic duct was visualized without the gallbladder and the common hepatic duct (4%); and Pattern 4, the common bile duct and the gallbladder with the pancreatic duct were visualized without the common hepatic duct (18%). In all of these 46 patients, laparotomy, an operative cholangiogram, and histological evaluation of the biliary duct were performed. In 9 neonates with neonatal hepatitis, the biliary tract was opacified and biliary atresia was excluded. Laparotomy was thus avoided in these neonates. There was no complication caused by either ERCP or by anesthesia.

Obstructive jaundice caused by neuroblastoma managed with temporary cholecystostomy tube

Neuroblastoma presenting as obstructive jaundice is very rare. The authors present two cases of neuroblastoma, one primary and one recurrent, manifesting as a malignant obstruction of the extrahepatic biliary system. Various methods of biliary decompression were considered in these children including transhepatic or retrograde biliary stenting and internal cholecystoenteric bypass. An attempt at percutaneous transhepatic stent placement failed in one case. In each patient, a simple insertion of a cholecystostomy tube proved effective. Immediately postoperatively, both patients had rapid resolution in symptoms and a decrease in bilirubin levels. Transient mild cholangitis in both children was successfully treated with antibiotics. Chemotherapy reduced the tumor size in each case, and the cholecystostomy tubes were removed within 3 weeks, after cholangiography showed patency of the distal common bile ducts. Temporary cholecystostomy tube drainage and systemic chemotherapy proved to be a safe, simple, and effective method for managing obstructive jaundice caused by neuroblastoma in these two cases.

Neonatal cholestasis. New approaches to diagnostic evaluation and therapy

Neonatal cholestasis remains a major diagnostic challenge despite increasing knowledge regarding its pathogenesis. The time constraint and urgency in the investigational process is underscored by the age-dependent success rate of the surgical corrective procedures for EHBA. Appropriate interpretation of imaging and pathologic studies requires a pediatric center familiar with the entities causing neonatal cholestasis. When liver failure or progressive hepatic dysfunction is likely to occur, early referral to a liver transplant center is recommended. Despite the increasing experience and excellent results of pediatric liver transplantation, at this point, surgical corrective procedures such as the Kasai procedure remain the first line of treatment for most patients with EHBA.

ERCP and endoscopic sphincterotomy in infants and children with jaundice due to common bile duct stones

ERCP was performed in two infants (29 and 62 days old) and eight children (5 to 12 years old) with jaundice due to common bile duct stones. Seven patients had hemolytic anemia and three patients had a family history of gallstone disease. Successful cannulation of the common bile duct demonstrating stones was accomplished in all patients. Four patients had coexisting gallstones and were treated surgically. Six children who had previously undergone cholecystectomy were treated by endoscopic sphincterotomy and stone extraction without complication. We believe that ERCP should be utilized by expert endoscopists in children with evidence of extra-hepatic cholestasis, and endoscopic sphincterotomy should be the treatment of choice in children who have previously undergone cholecystectomy, and who are jaundiced secondary to common bile duct stones.

ERCP in the diagnosis of extrahepatic biliary atresia

This study assessed the usefulness of ERCP in the diagnosis of biliary atresia. We evaluated 57 infants with prolonged cholestasis with abdominal ultrasound, liver biopsy, and ERCP. Using clinical observations alone, 22 infants were thought to have biliary atresia; whereas 35 children were thought to have neonatal hepatitis. The ERCP was performed with a prototype duodenoscope and was successful in all infants except two with biliary atresia. In 20 infants three types of radiological findings consistent with biliary atresia were seen: type 1, no visualization of biliary tree (35%); type 2, opacification of the distal common duct and gallbladder without visualization of the main hepatic duct (35%); and type 3, opacification of the distal common duct, the gallbladder, and a segment of the main hepatic duct with biliary lakes at the porta hepatis (30%). Twenty-five of 35 infants with suspected neonatal hepatitis were excluded because of a liver biopsy that was diagnostic. In the remaining 10 infants the liver biopsy had some features of extrahepatic biliary atresia and ERCP was performed prior to surgery. A normal extrahepatic biliary tree was obtained in all of them. In conclusion, ERCP permits the visualization of the biliary tree in young infants and is useful in selecting those infants who should be considered for exploratory laparotomy.

Endoscopic retrograde cholangiopancreatography in infantile cholestasis

The difficulty of distinguishing surgically correctable causes of conjugated hyperbilirubinaemia in infants from other causes means that some infants may undergo laparotomy and intraoperative cholangiography unnecessarily, and others may be referred for surgery too late. In an attempt to improve the diagnostic accuracy in infants with conjugated hyperbilirubinaemia when standard methods produced equivocal results, we have been using prototype paediatric duodenoscopes (PJF 7.5 and XPJF 8.0; Olympus) to perform endoscopic retrograde cholangiopancreatography (ERCP). From 159 infants with conjugated hyperbilirubinaemia, 11 were referred for ERCP, which was performed in nine. In four in whom bile ducts were definitely visualised laparotomy was avoided. Operative cholangiography confirmed patent bile ducts in one in whom visualisation had been uncertain. Three of four in whom bile ducts were not seen had extrahepatic biliary atresia. Visible bile drainage in the fourth excluded atresia. No major complications ensued but there was radiological evidence of gall bladder perforation in one (common hepatic duct block) and overinflation with air was a problem until finer cannulae (Wilson-Cook) were introduced. In appropriately selected patients with conjugated hyperbilirubinaemia, ERCP with paediatric duodenoscopes in experienced hands may provide useful diagnostic information.