Hepatobiliary ultrasound and clinical findings in infants with suspected obstructive jaundice at Mulago national referral hospital

Abstract

Background: Jaundice is a common clinical sign in newborns, especially during the first 2 weeks after birth. Recent global statistics proposed that about 1.1 million babies a year may possibly develop severe jaundice and a big proportion of them live in sub-Saharan Africa and South Asia. Only a small proportion will fit into the category of obstructive or "surgical" jaundice, and only a few of the infants will eventually benefit from surgery. Far too often, however, the baby with a surgically correctable lesion dies because the damage to the liver parenchyma is irreversible by the time surgery is performed. The difficult task facing primary care providers is discriminating between serious conjugated hyperbilirubinemia and benign unconjugated jaundice because in the early stage, the infants can look very well except for their jaundice. High-resolution real-time ultrasonography serves as an important tool for differentiation of obstructive and non-obstructive causes of jaundice in infants and children, independent of liver function. Objectives: The objectives of this study were to determine the prevalence of obstructive jaundice among infants with suspected obstructive jaundice, to describe the clinical presentations of infants with suspected obstructive jaundice, to describe the hepatobiliary US findings in infants with suspected obstructive jaundice, and to correlate the hepatobiliary US and clinical findings in infants with suspected obstructive jaundice in MNRH Methodology: This was a hospital based cross sectional study. Infants with clinically suspected obstructive jaundice presenting to Mulago specialized hospital were recruited into the study with consent of the parents/caretakers. Patients’ demographic data and clinical history were taken and recorded in a data collection tool. A trans-abdominal hepatobiliary ultrasound scan was performed on all participants and the findings recorded. Results: A total of 74 infants were recruited into the study, and all had an abdominal ultrasound scan performed with focus on the hepatobiliary system. Out of the 74 infants, 50 were male (67.6%), and 24 were female (32.4%). The mean age of the participants was 4 months. The majority of the infants 34(46.0%) had non-obstructive jaundice, and 29(39.2%) of the infants enrolled had obstructive jaundice. In 11(14.8%) of the infants, the cause of jaundice could not be determined by ultrasound. Of the patients with obstructive jaundice, the most prevalent US findings were

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those associated with BA and these included the TC sign at 15(20.3%), small/atrophic GB at 16(21.6%), increased hepatic subcapsular flow at 19(25.7%), and increased hepatic artery to portal vein ratio at 14(18.9%). Twenty eight (96.6%) of the patients with obstructive jaundice had conjugated bilirubin levels >20% of the total, and 19(65.5%) had a raised serum alkaline phosphatase. Conclusion: More than a third of the infants suspected to have obstructive jaundice actually turn out to have obstructive jaundice. These typically present with dark urine and acholic stools. Ultrasound scan is a good imaging modality for distinguishing between obstructive and non-obstructive causes of jaundice in infants, but there is often need for supplemental imaging in cases where ultrasound is unable to provide conclusive diagnosis. Thorough clinical assessment with use of the parameters of percentage of conjugated bilirubin and levels of serum alkaline phosphatase can help to increase the clinical index of suspicion and ultrasound yield of obstructive jaundice.