Imaging in Pediatric Obstructive Jaundice.

Cholestatic jaundice characterized by elevated conjugated bilirubin can be due to multitude of factors in neonates and childhood. Extrahepatic biliary atresia (EHBA), choledochal cyst, neonatal hepatitis, cytomegalovirus (CMV), and biliary plug are some of the common causes in neonate and early infancy. Causes in late infancy and childhood comprises viral hepatitis, choledochal cyst, cholelithiasis, worm infestation, and biliary compression secondary to extrinsic causes (node, collection, tumor). Some serious disorders like biliary atresia must be considered with the emphasis on early diagnosis of treatable causes. In the modern era, with multiple diagnostic modalities available including high-resolution ultrasonography, magnetic resonance imaging (MRI), CT scan, and nuclear imaging [hepatobiliary iminodiacetic acid (HIDA) scan], rapid diagnosis can be made in many surgically treatable cases. The authors will discuss the imaging modality available with advantages, disadvantages, and common indications of each modality, and overview of obstructive jaundice discussing the wide spectrum of causes in neonates and late childhood. Combining available knowledge with careful and meticulous search can help narrow down the diagnosis and initiate prompt treatment.

Neonatal Jaundice.

Hyperbilirubinemia is a common occurrence in neonates; it may be physiological or pathological. Conjugated hyperbilirubinemia may result from medical or surgical causes, and can result in irreversible liver damage if untreated. The aim of imaging is the timely diagnosis of surgical conditions like biliary atresia and choledochal cysts. Abdominal ultrasound is the first line imaging modality, and Magnetic resonance cholangiopancreatography (MRCP) also has a role, especially in pre-operative assessment of choledochal cysts (CDCs). For biliary atresia, the triangular cord sign and gallbladder abnormalities are the two most useful ultrasound features, with a combined sensitivity of 95%. Liver biopsy has an important role in pre-operative evaluation; however, the gold standard for diagnosis of biliary atresia remains an intra-operative cholangiogram. Choledochal cysts are classified into types according to the number, location, extent and morphology of the areas of cystic dilatation. They are often associated with an abnormal pancreaticobiliary junction, which is best assessed on MRCP. Caroli's disease or type 5 CDC comprises of multiple intrahepatic cysts. CDCs, though benign, require surgery as they may be associated with complications like cholelithiasis, cholangitis and development of malignancy. Severe unconjugated hyperbilirubinemia puts neonates at high risk of developing bilirubin induced brain injury, which may be acute or chronic. Magnetic resonance imaging of the brain is the preferred modality for evaluation, and shows characteristic involvement of the globus pallidi, subthalamic nuclei and cerebellum - in acute cases, these areas show T1 hyperintensity, while chronic cases typically show hyperintensity on T2 weighted images.

Clinical Assessment of Differential Diagnostic Methods in Infants with Cholestasis due to Biliary Atresia or Non-Biliary Atresia.

The different methods in differentiating biliary atresia (BA) from non-BA-related cholestasis were evaluated in order to provide a practical basis for a rapid, early and accurate differential diagnosis of the diseases. 396 infants with cholestatic jaundice were studied prospectively during the period of May 2007 to June 2011. The liver function in all subjects was tested. All cases underwent abdominal ultrasonography and duodenal fluid examination. Most cases were subjected to hepatobiliary scintigraphy, magnetic resonance cholangiopancreatography (MRCP) and a percutaneous liver biopsy. The diagnosis of BA was finally made by cholangiography or histopathologic examination. The accuracy, sensitivity, specificity and predictive values of these various methods were compared. 178 patients (108 males and 70 females with a mean age of 58±30 days) were diagnosed as having BA. 218 patients (136 males and 82 females with a mean age of 61 ±24 days) were diagnosed as having non-BA etiologies of cholestasis jaundice during the follow-up period in which jaundice faded after treatment with medical therapy. For diagnosis of BA, clinical evaluation, hepatomegaly, stool color, serum gamma-glutamyltranspeptidase (GGT), duodenal juice color, bile acid in duodenal juice, ultrasonography (gallbladder), ultrasonography (griangular cord or strip-apparent hyperechoic foci), hepatobiliary scintigraphy, MRCP, liver biopsy had an accuracy of 76.0%, 51.8%, 84.3%, 70.0%, 92.4%, 98.0%, 90.4%, 67.2%, 85.3%, 83.2% and 96.6%, a sensitivity of 83.1%, 87.6%, 96.1%, 73.7%, 90.4%, 100%, 92.7%, 27.5%, 100%, 89.0% and 97.4%, a specificity of 70.2%, 77.5%, 74.8%, 67.0%, 94.0%, 96.3%, 88.5%, 99.5%, 73.3%, 75.4% and 94.3%, a positive predictive value of 69.0%, 72.6%, 75.7%, 64.6%, 92.5%, 95.7%, 86.8%, 98.0%, 75.4%, 82.6% and 98.0%, and a negative predictive value of 83.6%, 8.5%, 95.9%, 75.7%, 92.3%, 100%, 84.2%, 93.7%, 100%, 84.0% and 92.6%, respectively. It was concluded that all the differential diagnosis methods are useful. The test for duodenal drainage and elements is fast and accurate. It is helpful in the differential diagnosis of BA and non-BA etiologies of cholestasis. It shows good practical value clinically.

Ultrasonography evaluation of infants with Alagille syndrome: In comparison with biliary atresia and neonatal hepatitis.

OBJECTIVE: To evaluate the ultrasonography (US) features of Alagille syndrome (ALGS), as compared with biliary atresia (BA) or neonatal hepatitis (NH). METHODS: Our study included 23 ALGS, 75 BA and 70 NH patients. The initial US images were retrospectively reviewed for gallbladder (GB) morphology with systemic classification, GB length and luminal area, presence of triangular-cord (TC) sign and hypertrophied hepatic-artery. The presence of anomalies associated with ALGS was evaluated. The diagnostic values of each finding and their combinations were evaluated. RESULTS: Both ALGS (57%) and BA (79%) were more frequently associated with abnormal GB shapes than NH (19%, all P<0.001). The short and small GBs were more frequently observed in ALGS and BA than in NH (all P<0.001). None in the ALGS and NH showed TC sign, while 41% in the BA did (all P<0.001). Hypertrophied hepatic-artery was noted less frequently in both ALGS (13%) and NH (14%) than in BA (83%, all P<0.001). The combination of US criteria with associated anomalies increased the positive-predictive-value for ALGS. CONCLUSION: Abnormal shaped GB with absence of the TC sign and hypertrophied hepatic-artery and presence of associated anomalies can be a differential point of ALGS.

Bilirubin levels predict renal cortical changes in jaundiced neonates with urinary tract infection.

BACKGROUND: This study was undertaken to determine the incidence of urinary tract infection (UTI) and the frequency of anatomical abnormalities in newborns with unexplained jaundice and to find out if there is any correlation between bilirubin level and renal damage. METHODS: We studied 462 full-term neonates for UTI. They were aged 3-25 days, with either high (>10 mg/dL) or prolonged (>10 days) hyperbilirubinemia, with or without manifestations such as fever, vomiting, diarrhea, poor feeding, lethargy, and irritability. Neonates positive for UTI were further investigated with ultrasound, cystourethrography, and acute phase renal scintigraphy with technetium-99m dimercaptosuccinate acid (DMSA). RESULTS: Thirty neonates (6.5%) were found to have UTI. Twenty-eight of them had indirect hyperbilirubinemia and two had direct hyperbilirubinemia, with total bilirubin levels of 11.8-20.1 mg/dL. None of the neonates was found to have jaundice because of other reasons such as infection. Vesicoureteral reflux was found in 5 neonates and one of them was combined with hydronephrosis. Renal scintigraphy with technetium-99m DMSA showed renal cortex changes in 14 (46.7%) of the 30 neonates with UTI. These 14 neonates also had increased levels of bilirubin in comparison to those with normal findings of DMSA. CONCLUSIONS: The incidence of UTI in uncomplicated neonatal jaundice is relatively high. Anatomical abnormalities of the urinary tract are not rare in infected children. Increased bilirubin levels are related to pathological findings in renal scintigraphy.

[Chemotherapy-induced fetal anemia in maternal acute myelocytic leukemia]. / Chemotherapieinduzierte fetale Anämie bei akuter myeloischer Leukämie der Mutter.

This article discusses the management of a pregnancy of a 32-year-old primigravida with acute myelocytic leukemia treated with induction chemotherapy starting in the 20 + 5 week of gestation. Sonographic monitoring showed evidence of fetal ascites and anemia that could be treated with an intrauterine fetal transfusion. After maternal recovery, a caesarean section was performed in the 27 + 5 week of gestation. We delivered a vivid eutrophic female prematurely. The infant showed persisting signs of myelosuppression. Two further transfusions had to be performed. The present report describes the interdisciplinary therapeutic management when polychemotherapy during pregnancy is necessary for the mother. Cases of acute leukemia in pregnancy are complicated by severe prenatal risks caused by the hematologic illness and by the immediate beginning of chemotherapy. In the third trimester premature delivery is preferable to intrauterine exposition to cytostatic agents. In the second trimester the pregnancy has to be monitored for the typical risks and complications of chemotherapy. Fetal cytotoxic myelosuppression is detectable by prenatal observation so that interventional strategies are feasible.

[The role of hepatobiliary scintigraphy in neonates with persistant jaundice]. / Betydningen af galdevejsskintigrafi hos neonatale med prolongeret ikterus.

Hepatobiliary scintigraphy of infants being examined for persistant neonatal jaundice is best carried out using mebrofenin, a 99m Tc-labeled IDA derivative. This article summarizes the most frequently occurring etiologies of persisting neonatal jaundice and the diagnostic work-up of this condition. Perinatal obliteration of extrahepatic bile ducts requires immediate surgery, whereas other causes of persisting jaundice may be treated medically and/or conservatively.

Ursodeoxycholic acid-augmented hepatobiliary scintigraphy in the evaluation of neonatal jaundice.

UNLABELLED: Early differentiation of extrahepatic biliary atresia from intrahepatic cholestasis is important. Hepatobiliary scintigraphy is an excellent noninvasive investigation for ruling out extrahepatic biliary atresia. This study aimed at identifying the role of ursodeoxycholic acid (UDCA), a choleretic agent, in conjunction with hepatobiliary scintigraphy in differentiating extrahepatic biliary atresia from neonatal hepatitis. METHODS: Fifty-one infants (42 male, 9 female) aged 0.3-5.5 mo (mean, 2.9 mo) presenting with neonatal jaundice underwent 99mTc-mebrofenin hepatobiliary scintigraphy. For patients who did not show any excretion of tracer into the intestine till 24 h, the study was repeated after oral administration of UDCA (20 mg/kg every 12 h) for 48-72 h. Ultrasonography and, if required, liver biopsy and intraoperative cholangiography were used with clinical data such as stool color and serologic and other etiologic investigations to form a final diagnosis. RESULTS: Of 51 patients, 19 showed biliary excretion in the first study, ruling out extrahepatic biliary atresia. Neonatal hepatitis was the final diagnosis in these. Of the remaining 32 patients, 12 nonexcretors converted to excretors after UDCA treatment, whereas 20 still showed no biliary drainage. Four nonexcretors on scintigraphy had a final diagnosis of neonatal hepatitis with galactosemia; the remaining 16 had extrahepatic biliary atresia. The specificity of hepatobiliary scintigraphy in ruling out extrahepatic biliary atresia improved from 54.3% to 88.6% (P < 0.001) after UDCA treatment. None of the patients experienced any ill effects from UDCA administration. CONCLUSION: Pretreatment with UDCA significantly improves the specificity of hepatobiliary scintigraphy in ruling out extrahepatic biliary atresia as a cause of prolonged neonatal jaundice.

Biliary atresia: making the diagnosis by the gallbladder ghost triad.

OBJECTIVE: To describe the gallbladder ghost triad and evaluate its usefulness in the sonographic diagnosis of extrahepatic biliary atresia (BA). METHODS: From October 1997 to February 2002, 217 fasted infants with cholestatic jaundice aged 2-12 weeks were examined sonographically. We defined the gallbladder ghost triad as gallbladder length <1.9 cm, lack of smooth/complete echogenic mucosal lining with an indistinct wall and irregular/lobular contour, and used it as a criteria for BA. Gallbladder wall thickness, triangular cord, diffuse periportal echogenicity and hepatic artery calibre were also recorded. Diagnosis of BA was confirmed surgically and histologically. RESULTS: Thirty of 31 babies with BA demonstrated the gallbladder ghost triad. No false-positives were recorded. The 31st BA baby showed a normal gallbladder at 6 weeks, but developed the ghost triad at 8 weeks. Gallbladder wall thickening was seen in 46/186 non-BA babies, but not in BA. Triangular cord was observed in 24/31 babies. Twenty-two of 186 non-BA babies and 5/31 BA babies showed diffuse periportal echogenicity. The hepatic artery appeared more prominent in BA. All 31 babies diagnosed sonographically as BA had surgery. Three non-BA babies had "negative" laparotomies showing hypoplastic bile ducts. CONCLUSIONS: The gallbladder ghost triad is a very accurate sign of BA. Indeterminate cases require close follow-up.

Pediatric liver imaging.

The evaluation of hepatic diseases in children is often a multimodality process, requiring multiple imaging tests to determine the cause and extent of an abnormality. Ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) have distinct roles to play in the evaluation of hepatic disease in children. This article addresses the hepatic and biliary lesions that are unique or more common in children and describes their cross-sectional imaging characteristics. In addition, the techniques and protocols for US, CT, and MRI are reviewed.

Color Doppler sonography in the diagnosis of neonatal intrahepatic portosystemic shunts.

Intrahepatic portosystemic shunts are infrequent in children. We report 3 cases of neonates who presented with jaundice during the first month of life. Color Doppler sonography in the first 2 cases showed direct communication between the right portal and hepatic veins. Both infants were asymptomatic, and the shunts disappeared spontaneously. The third case involved several shunts and an aberrant medial portal vein. This patient developed heart failure and died after surgery. Color Doppler sonography was useful in the diagnosis and follow-up of the shunts in all 3 cases.

Gallbladder contraction in biliary atresia: a pitfall of ultrasound diagnosis.

In 3 (9 %) of 34 children with biliary atresia, US revealed gallbladder contraction following an oral feed, given on admission, but not with subsequent feeds. Surgery revealed a Kasai type IIIa biliary atresia with a patent communication between the gallbladder and duodenum. We propose that the bile ducts may initially have been patent, but then gradually became obliterated secondary to inflammation. These cases may explain the development of one type of biliary atresia.

Pediatric hepatic imaging.

Common indications for liver imaging in children include trauma, suspected mass, pre-liver transplantation, monitoring after liver transplantation, jaundice, or liver dysfunction. This article highlights areas where the pathology or imaging approach in children differs from that seen in adults. Topics covered include imaging of a suspected hepatic mass, neonatal jaundice, and segmented liver transplantation.

Ultrasonographic "triangular cord": the most definitive finding for noninvasive diagnosis of extrahepatic biliary atresia.

Early diagnosis of extrahepatic biliary atresia (EHBA) is very important for a successful bile drainage procedure. An urgent and extensive investigation is warranted to make a differential diagnosis of EHBA from other cholestatic disease, especially neonatal hepatitis (NH). The diagnosis may be made by laparotomy with cholangiogram and liver biopsy but these procedure are invasive. Because a cone-shaped fibrous tissue was always found at the porta hepatis during Kasai's procedure and that type of fibrous tissue has never been seen in other types of cholestatic jaundice, the authors have used ultrasonography (US) to detect fibrous remnants at the porta hepatis in infants clinically suspected of having EHBA and identified a triangular- or tubular-shaped echogenic density in the bifurcation of the portal vein at the porta hepatis in EHBA and called it an ultrasonographic "triangular cord (TC)". The authors determined that the presence of TC denoted the EHBA. On the other hand, nonvisualization of TC was interpreted as consistent with NH. In the present study, the authors reviewed ultrasonographic examination and hepatobiliary scintigraphy in a series of 41 infants suspected of having EHBA or NH. The TC was identified in thirteen infants. In twelve of thirteen infants with TC found by US, the diagnosis of EHBA was confirmed at the time of Kasai's Roux-en-Y hepatoportojejunostomy operation. The remaining one died at 15 months of age without having treatment. TC was not visualized in 28 infants. Twenty-seven of 28 infants with absent TC improved clinically through medical treatment for NH. The other, diagnosed to have NH by needle and wedge liver biopsies, eventually showed a TC on follow-up US examination performed 40 days after the initial examinations. Moreover, follow-up percutaneous liver biopsy specimen showed typical findings of biliary atresia with bile duct proliferation and portal fibrosis. The patient underwent a Kasai hepatoportoenterostomy. On review of the hepatobiliary scintigraphy, all 13 infants with TC had no intestinal excretion of isotope. Thirteen of 28 infants (46%) without TC also had no intestinal excretion of isotope in the 24hour follow-up but all of them were confirmed to have NH by percutaneous liver biopsy and their subsequent clinical course confirmed NH with the detection of bile in their stool except one. On the basis of these results, the authors conclude that ultrasonographic TC is a very specific finding representing the fibrous cone at the porta hepatis and is a quick, simple, and definitive tool in the noninvasive diagnosis of EHBA. If TC is visualized, no further studies are necessary and exploratory-laparotomy can be done. If TC is not visualized, hepatobiliary scintigraphy is recommended to demonstrate bile duct patency. Percutaneous liver biopsy is only required if neither TC nor intestinal excretion of isotope is seen. However, early exploration or close US follow-up study is recommended in any patient suspected of having EHBA clinically, even if liver biopsy confirms the presence of NH.

Evaluation of mebrofenin hepatoscintigraphy in neonatal-onset jaundice.

BACKGROUND: The prognosis of infants with prolonged neonatal jaundice is dependent on early diagnosis because of the need for prompt surgical management of biliary atresia. OBJECTIVE: To evaluate the usefulness of 99 mTcm-trimethylbromo-iminodiacetic acid (TBIDA, mebrofenin) in the investigation of infantile jaundice. MATERIALS AND METHODS: A retrospective study was undertaken of 58 patients with unexplained prolonged neonatal jaundice. Sixty-eight scans were reviewed. RESULTS: Mebrofenin scintigraphy confirmed the presence of a choledochal cyst in three of the four cases with that diagnosis. There were no false negative results in the nine patients with extrahepatic biliary atresia (EHBA). Three further infants had an incorrect histological diagnosis of EHBA. A gall bladder was identified by US in each case and in one of these, scintigraphy showed gut excretion. In the 16 patients with no gut excretion by 24 h, the final diagnoses were intrahepatic cholestasis (n = 7), Alagille's syndrome (n = 3), neonatal hepatitis (n = 3), alpha-1-antitrypsin deficiency (n = 2) and juvenile xanthogranuloma (n = 1). Seven infants had repeat scintigraphy after the administration of ursodeoxycholic acid (URSO). This changed five non-excretors with hepatitis into excretors. Two infants with hepatitis continued to show non-excretion after URSO, but a gallbladder was identified by US in both. CONCLUSIONS: Mebrofenin scintigraphy is accurate in confirming the presence of a choledochal cyst and in refuting the diagnosis of EHBA. While histology and scintigraphy are each 100 % sensitive for the diagnosis of EHBA, neither, individually, is accurate and the investigation of prolonged neonatal jaundice requires a multi-modality imaging strategy.

[Value of sonography in prolonged neonatal jaundice. Findings in 13 cases]. / Place de l'échographie dans l'ictère néonatal prolongé. A propos de 13 cas.

BACKGROUND: Different conditions are associated with a prolonged cholestatic jaundice in the neonatal period: viral hepatitis, biliary atresia and choledocal cyst are the most frequent causes. Laboratory findings are necessary, although they do not permit an etiologic diagnosis in all cases. Serial ultrasonographic study could be proposed for the evaluation of biliary excretion before and after feeding, in order to differentiate between these three conditions. PATIENTS AND METHODS: Between February 1993 and January 1997, 13 newborns (seven girls and six boys) aged from 30 to 186 days, presented with jaundice and conjugated hyperbilirubinemia. They were evaluated by laboratory tests; serial ultrasonographic examinations were performed after 4 hours fasting then 1 and 2 hours after meal. RESULTS: The gallbladder (GB) was visualized in nine patients. In five of these patients, it contracted after feeding suggesting the diagnosis of neonatal hepatitis, that was confirmed by the clinical evolution. In three patients, the GB did not change in size and the diagnosis of biliary atresia was surgically proven. In one patient, a choledocal cyst was visualized and confirmed by surgery. The GB was not identified after 4 hours of fasting in four patients; biliary atresia was suspected and confirmed by surgery. CONCLUSION: Serial ultrasound of the GB is an easy and non-invasive method. It was useful in identifying those conditions requiring surgery in eight patients. We recommend its use as the initial method in the evaluation of neonatal jaundice before the other invasive methods.

Outcome of hepatobiliary scanning in neonatal hepatitis syndrome.

UNLABELLED: To evaluate the diagnostic information gained from hepatobiliary scanning in infants, we reviewed 86 consecutive infants who were < or = 4 mo old and were treated for conjugated hyperbilirubinemia at the Hospital for Sick Children in Toronto between 1985 and 1993 and who had technetium iminodiacetic hepatobiliary scanning and a percutaneous liver biopsy performed in close temporal proximity. METHODS: Retrospective reviews of hospital charts and blinded reviews of hepatobiliary scans were performed. RESULTS: There were 58 male and 28 female infants (age range, 2-124 days; mean = 65 days). Hepatobiliary scanning failed to show biliary excretion into the gastrointestinal tract in 53 of 86 patients. Forty of these 53 had extrahepatic biliary atresia. The remaining 33 patients demonstrated biliary excretion into the gastrointestinal tract; 24 of 33 had neonatal hepatitis. Among 13 of the 53 patients who had no evidence of biliary excretion and who also did not have extrahepatic biliary atresia, 8 had idiopathic neonatal hepatitis, 4 had interlobular bile duct paucity and 1 had total parenteral nutrition-associated cholestasis. In this large series, no patient with extrahepatic biliary atresia showed bile drainage on hepatobiliary scanning. Fifty percent of patients with interlobular bile duct paucity but no extrahepatic obstruction failed to show biliary excretion of radionuclide. Twenty-five percent of patients (8 of 32) with idiopathic neonatal hepatitis demonstrated no biliary excretion. Hepatocellular extraction was examined by semiquantitative analysis in the nondraining, nonbiliary atresia patients (12 of 53). Four of these 12 patients demonstrated poor liver extraction. Three patients had idiopathic neonatal hepatitis, and one had bile duct paucity. Therefore, four of eight neonatal hepatitis patients had normal extraction, suggesting that poor versus good liver hepatocyte clearance cannot accurately identify neonatal hepatitis. CONCLUSION: Hepatobiliary scanning requires cautious interpretation. Nondraining scans may indicate severe neonatal hepatitis or the presence of interlobular bile duct paucity.

HIDA kinetics in children.

Quantitative analyses were performed on paediatric HIDA scans (EHIDA and DISIDA) to measure the flow rates of HIDA into and out of the liver. Analysis of the tracer outflow rate indicated that HIDA appeared to leave the liver even when there was complete biliary obstruction, implying 'leakage' from hepatocytes back into the blood. This potentially explains why a 'hepatogram' does not provide useful information about hepatic obstruction, whereas a renogram does yield useful information about renal outflow obstruction. In a small group of patients with no evidence of either hepatocellular disease or obstruction, the HIDA inflow rate into the liver was 0.003072 s(-1), which is similar to published colloid uptake rates in normal livers. This implies that although the two radiopharmaceuticals are taken up by different mechanisms, both mechanisms have a very similar extraction fraction. Patients with cirrhosis had a considerably reduced HIDA uptake rate (0.001072 s[-1]), and once again this was similar to colloid uptake from the blood in cirrhosis. Patients investigated for neonatal jaundice all showed reduced HIDA inflow, and this reduction was greatest (mean 0.000477 s[-1]) in those neonates whose jaundice was due to hepatocellular impairment. In biliary atresia, the HIDA rate was reduced to approximately 0.001040 s(-1), which was still considerably higher than the rate from patients with neonatal jaundice due to sufficient hepatocellular impairment to cause complete cholestasis.

Comparison technetium of Tc-99m disofenin cholescintigraphy with ultrasonography in the differentiation of biliary atresia from other forms of neonatal jaundice.

Technetium Tc-99m disofenin cholescintigraphy (CS) and ultrasonography (US) are two major clinical methods used in differentiating biliary atresia (BA) from neonatal jaundice. To compare the diagnostic utility of these two modalities, 66 patients with neonatal cholestasis (15 BA, 3 choledochal cyst (CC), 32 neonatal hepatitis, 13 prolonged jaundice, 2 total parenteral nutrition, and 1 sepsis) underwent Tc-99m disofenin CS and US. The diagnostic sensitivity, specificity, and accuracy of CS in differentiating BA from other forms of neonatal jaundice was 100%, 87.5%, and 90.5%, respectively, and for US 86.7%, 77.1%, and 79.4%, respectively. Tc-99m disofenin CS after premedication with phenobarbital and cholestyramine is a convenient and reliable method of differentiating BA from neonatal hepatitis, with a diagnostic accuracy superior to that of US. However, US is the initial imaging procedure of choice in patients presenting with jaundice to rule out anatomic anomalies such as CC.

Utility of Tc-99m mebrofenin scintigraphy in the assessment of infantile jaundice.

Technetium-99m mebrofenin hepatobillary excretory patterns were assessed in 36 infants with hyperbilirubinemia. Phenobarbital was administered to 22 patients before imaging. Final diagnoses included: intrahepatic cholestasis (14 patients), neonatal hepatitis (nine patients), biliary atresia (eight patients), alpha-1-antitrypsin deficiency (two patients), Alagille's syndrome (two patients), and cystic fibrosis (one patient). No patient with biliary atresia showed bowel activity by 24 hours. Of the 28 infants without biliary atresia, 23 (82%) had bowel activity visualized by 6-8 hours and 26 (90%) had bowel activity by 24 hours. Two had no bowel activity at 24 hours: one had cystic fibrosis and one had neonatal hepatitis. Of the 26 patients with bowel visualization, the time to visualize bowel did not differ between patient groups with and without phenobarbital induction. All of the patients with hepatitis, including those with marked dysfunction, showed good hepatic uptake. Mebrofenin scintigraphy is an important imaging technique in the diagnostic evaluation of infants with hyperbilrubinemia. In addition to biliary atresia, intrahepatic cholestasis due to cystic fibrosis and severe neonatal hepatitis may also cause bowel nonvisualization up to 24 hours. The results of this study suggest phenobarbital induction may not be needed when Tc-99m mebrofenin scintigraphy is used for the assessment of infantile jaundice.