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We present a 10-week-old infant who presented with cholestasis. Biliary obstruction secondary to massive pancreatic infiltration was demonstrated by ultrasound. A diagnosis of acute lymphoid leukemia was confirmed. Enlargement of the pancreas is unusual both in this age group and in leukemia. Infantile leukemia, although rare and usually not associated with gastrointestinal presentations, should be considered as a cause of pancreatic enlargement and neonatal cholestasis.

PURPOSE/OBJECTIVE:To retrospectively analyze prospective magnetic resonance (MR) cholangiographic interpretations of findings and compare them with clinical outcome and to determine the accuracy of MR cholangiography in depicting extrahepatic biliary atresia and helping to distinguish it from other causes of neonatal jaundice. MATERIALS AND METHODS/METHODS:Twenty-six infants (15 male, 11 female; median age, 2 months) underwent MR cholangiography with a 1.5-T MR imaging unit. Original interpretations were compared with clinical outcome. Statistical analysis was performed to determine the accuracy of MR cholangiography in depicting extrahepatic biliary atresia. Equivocal cases and any cases lost to follow-up were excluded. RESULTS:Findings in six of 26 infants were interpreted as normal, and none of five patients (one lost to follow-up) had biliary atresia or other surgical lesions; two were abnormal but not suggestive of biliary atresia (one false-negative finding); 12 were consistent with biliary atresia (three false-positive findings); four demonstrated a choledochal cyst; and two were equivocal. MR cholangiography accuracy was 82% (19 of 23); sensitivity, 90% (nine of 10); and specificity, 77% (10 of 13) for the detection of extrahepatic biliary atresia, with a positive predictive value of 75% (nine of 12) and a negative predictive value of 91% (10 of 11). CONCLUSION/CONCLUSIONS:Results of this study found that MR cholangiography is 82% accurate, 90% sensitive, and 77% specific for depicting extrahepatic biliary atresia. Contrary to previous reports, false-positive and false-negative findings occur at MR cholangiography.

Pediatric liver transplantation has matured into a well-established, highly successful treatment for advanced pediatric liver disease. Recent 1-year success rates range from 85% to 95%. This unprecedented achievement is the result of careful selection criteria and optimal timing of transplantation, technical advances in surgical technique, and improved treatment following transplant. This report highlights many recent published findings representing advances that have led to current successful approaches.

We reviewed the results of 50 magnetic resonance (MR) cholangiograms to evaluate their usefulness in directing clinical management in young patients after liver transplantation (LTx). Thirty-two patients underwent 50 MR cholangiograms on a 1.5-T unit. Studies were performed from 1 week to 16 yr after LTx. Indications included biochemical abnormalities with (n = 19) or without (n = 16) biopsy evidence for chronic rejection, sepsis (n = 14), and intractable ascites (n = 1). Original interpretations were compared to laboratory and ultrasound findings, and clinical outcome. Of 19 studies performed on 14 patients with biopsy evidence of chronic rejection, 16 were abnormal on MR (but only one was abnormal on ultrasound), resulting in corrective surgery (n = 1), re-Tx (n = 1), and endoscopic dilatation (n = 1). Of 16 studies on 16 patients with biochemical abnormalities without evidence of chronic rejection on biopsy, 14 were abnormal on MR (but only five of 13 on ultrasound), leading to corrective surgery (n = 3) and re-listing for Tx (n = 3). Thirteen of 14 studies on six patients with sepsis were abnormal on MR (five of nine were abnormal on ultrasound), identifying surgically correctable strictures (n = 2), and leading to re-Tx (n = 1) and percutaneous biliary drainage procedures (n = 2). The one patient with ascites had a normal study. We advocate usage of MR cholangiography for the detection of biliary complications after LTx, particularly in those patients who present with biochemical abnormalities that are not easily explained by acute cellular rejection or viral infection and in those with biliary sepsis.

BACKGROUND:Risk factors for the development of posttransplant lymphoproliferative disease (PTLD), a major cause of morbidity and mortality after pediatric liver transplantation, are primary Epstein-Barr virus (EBV) infection and intensity of immunosuppression. The authors assessed monitoring of EBV replication and preemptive immunosuppression reduction in pediatric liver transplant recipients. METHODS:The authors prospectively followed monthly EBV-quantitative competitive polymerase chain reaction to measure EBV replication in 23 patients who underwent liver transplant between July 1997 and November 1998. Preemptive immunosuppression reduction was instituted for significant EBV replication. Patients were followed up for at least 1 year and divided in two groups for analysis (group 1, pretransplant seronegative for EBV [13 patients]; group 2, seropositive for EBV [10 patients]). RESULTS:In group 1, 9 of 13 patients had positive polymerase chain reaction results at a mean time of 22.4 weeks after transplantation. All but one of these patients were asymptomatic. In seven of nine patients, preemptive immunosuppression reduction was undertaken without development of PTLD or rejection. In two of nine patients, immunosuppression could not be continuously reduced, and both patients experienced low-grade and medically responsive PTLD. In no patient in group 2 did an EBV-positive viral load or PTLD develop. CONCLUSIONS:Prospective longitudinal measurement of EBV by quantitative competitive polymerase chain reaction permits early detection of asymptomatic viral replication. Subsequent preemptive reduction of immunosuppression may prevent the progression to PTLD.

OBJECTIVE:Our objective was to describe the MR cholangiography findings for young patients with suspected biliary disease who underwent half-Fourier acquisition fast spin-echo technique with respiratory triggering. SUBJECTS AND METHODS/METHODS:Twenty-eight MR cholangiography studies were performed in 22 patients on a 1.5-T MR unit. Ten of these 22 patients had undergone liver transplantation. RESULTS:MR cholangiography revealed abnormalities of both the extrahepatic and the intrahepatic major and minor bile duct systems, despite the small diameter of the duct system in this group of patients. Four patterns of biliary disease were shown: global dilatation of extrahepatic or intrahepatic ducts (n = 7); segmental, uniform dilatation of central or peripheral intrahepatic ducts (n = 9); segmental, nonuniform dilatation of central or peripheral intrahepatic ducts (n = 2); and fusiform ectasia with segmental, irregular intrahepatic dilatation and bile lakes (n = 2). The findings of eight studies were interpreted as normal. The four patterns of abnormalities were correlated with the results from percutaneous transhepatic cholangiography, T-tube cholangiography, and liver biopsy and with clinical and surgical information, as available. CONCLUSION/CONCLUSIONS:MR cholangiography is a noninvasive technique for evaluation of biliary disease. The improved resolution afforded by respiratory triggering permits evaluation of both major and minor bile ducts, even in young, uncooperative subjects. Four patterns of abnormalities were prospectively identified, correlated with other information, and used to direct clinical treatment.

BACKGROUND:Posttransplant lymphoproliferative disease (PTLD) remains a significant cause of morbidity and mortality in pediatric liver transplant recipients. Epstein-Barr Virus (EBV) mismatch associated with more prevalent use of split-liver, reduced size, and living-related transplants has increased the risk of primary EBV infection and subsequent PTLD. Early identification of EBV viremia may reduce the risk of PTLD, because it allows for early adjustment of immunosuppression and antiviral therapy. METHODS:EBV viral load was measured monthly by quantitative competitive polymerase chain reactions in three pediatric liver transplant recipients. RESULTS:Onset of EBV viremia was documented in one recipient. Established EBV viremia was followed in the other two recipients (one with chronic rejection and one with PTLD) who were initially tested once monitoring was initiated in our program. CONCLUSIONS:EBV quantitative competitive polymerase chain reactions may represent a promising way to follow EBV viral load and potentially prevent the development of PTLD.