Imaging of neonatal cholestasis

The Role of Liver Biopsy in Investigation of Cholestatic Liver Disease in Infancy

Objectives

The objective of this study was to assess the diagnostic yield and impact on management of liver biopsy in infants with cholestatic jaundice.

Methods

A retrospective cohort study of infants with cholestasis who underwent liver biopsy before one year of age between December 2002 and December 2013 at the Montreal Children’s Hospital was conducted. Biopsies were reviewed by a single pathologist. The diagnostic yield of the biopsy was assessed in terms of its role in establishing a diagnosis, excluding an important diagnosis or changing management.

Results

Seventy-nine biopsies were performed within the time frame outlined, with 58 fulfilling inclusion criteria. Liver biopsies were found to add novel information in 21 cases (36.2%). The diagnostic yield of the biopsy was unrelated to the severity of direct hyperbilirubinemia, age at biopsy, age at admission, co-morbidities, stool color at presentation and TPN exposure. Among infants under 90 days of age, 21 also underwent cholangiography, the results of which were consistent with biopsy findings. There were four (6.9%) documented complications from biopsies, including bleeding and accumulation of free fluid in the peri-hepatic area.

Conclusions

Liver biopsy is an invasive test used with other clinical modalities to determine the etiology of neonatal cholestasis. These results suggest that biopsy added novel information to the diagnostic workup in 36.2% of cases with a complication rate of 6.9%. Consequently, the role and timing of liver biopsy need to be reassessed to determine which patients would most benefit from this procedure.

Using volume index and lateral hepatic angle to differentiate biliary atresia from TPN-associated cholestasis

OBJECTIVES

Differential diagnosis between biliary atresia (BA) and total parenteral nutrition-associated cholestasis (TPN-AC) and early treatment for cholestatic infants are challenges for evaluating neonatal or infantile cholestasis. The aim of our retrospective study was to apply noninvasive indices of magnetic resonance images to differentiate BA from TPN-AC.

METHODS

A total of 44 patients diagnosed as having BA (n = 30) or TPN-AC (n = 14) were included in the present retrospective study and underwent abdominal magnetic resonance imaging to evaluate the possibility of BA. The left lateral hepatic angle was determined from the coronal image of the left portal vein and portal vein of segment II. Adjusted volume indices of the right hepatic lobe (AVIR) and left lateral segment (AVILL) were calculated as the product of 3 diameters (centimeters) divided by each patient's body weight.

RESULTS

The left lateral hepatic angles of patients with BA (74° ± 21°) were significantly larger than for patients with TPN-AC (33° ± 9°) and controls (36° ± 5°, P < 0.05). AVILL of the BA (0.037 ± 0.012 cm/g) and TPN-AC groups (0.042 ± 0.030 cm/g) were not significantly different (P = 0.61) but were significantly larger than for controls (0.020 ± 0.011 cm/g) (P < 0.05). The right hepatic lobe to left lateral hepatic segment ratio (RLR) of patients with BA was significantly (P < 0.05) smaller (1.61 ± 0.58) than for patients with TPN-AC (3.08 ± 2.43) and controls (2.98 ± 0.92). Patients with BA could have relative sparing and selective enlargement of the left lateral liver with a resultant lobar difference and blunt left lateral hepatic angle.

CONCLUSIONS

Noninvasive indices of lobar difference and left lateral hepatic angle help differentiate patients with BA from those with TPN-AC.

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.

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.

Hepatobiliary scintigraphy in children

Hepatobiliary scintigraphy using iminodiacetic (IDA) radiopharmaceuticals provides clinically useful information on the function of the biliary tract in a variety of pathological processes in children, including neonatal jaundice, gallbladder dysfunction, trauma, and liver transplantation. Phenobarbital premedication (5 mg/kg per day for a minimum of 5 days in divided doses) is used in infants who are being examined for neonatal jaundice to increase the accuracy of 99mTc-IDA scintigraphy in differentiating extrahepatic biliary atresia from neonatal hepatitis. Biliary atresia can be ruled out in an infant if a patent biliary tree is shown with passage of activity into the bowel. If no radiopharmaceutical is noted in the bowel on imaging up to 24 hours, distinction between severe hepatocellular disease and biliary atresia cannot be made. The literature reports 91% accuracy, 97% sensitivity, and 82% specificity for hepatobiliary imaging in the diagnosis of biliary atresia. The impairment of both intrahepatic and extrahepatic biliary drainage is an important cause of liver disease in cystic fibrosis. Hepatobiliary scintigraphy in cystic fibrosis has shown characteristic patterns of dilatation of mainly the left hepatic duct, narrowing of the distal common bile duct, gallbladder dysfunction, and delayed bowel transit. Cholecystitis in children may be acalculous. Sensitivity and specificity for the scintigraphic diagnosis of acute acalculous cholecystitis is reported to range from 68% to 93% and 38% to 93%, respectively. Cholescintigraphy in a suspected bile leak provides information generally not available with other techniques, except for direct cholangiography. If the amount of intraperitoneal accumulation of the tracer is greater than that entering the gastrointestinal tract, surgery is usually indicated. Hepatobiliary imaging in children who have undergone liver transplantation will assess graft vascularity, parenchymal function, biliary drainage, presence of a leak, and obstruction.