The effect of phenobarbital on the accuracy of technetium-99m diisopropyl iminodiacetic acid hepatobiliary scintigraphy in differentiating biliary atresia from neonatal hepatitis syndrome.

Biliary atresia (BA) and neonatal hepatitis syndrome (NHS) are major causes of cholestatic jaundice in infancy. Technetium-99m diisopropyl iminodiacetic acid hepatobiliary scintigraphy (99mTc-DISIDA scan) is widely used in the differentiation of these two entities. The objective of this study was to evaluate the effect of phenobarbital premedication on the accuracy of 99mTc-DISIDA scan. Ninety-five cholestatic infants (38 females and 57 males) with an age range of 2 weeks to 4 months (mean 2.1 mo) who underwent 99mTc-DISIDA scan testing were retrospectively reviewed. The patients were divided into 3 groups according to the history of phenobarbital administration prior to 99mTc-DISIDA scan examination. Group 1 (n = 48), group 2 (n = 29), and group 3 (n = 18) received phenobarbital at the dosage of 5 mg/kg/day for at least 5 days, less than 5 mg/kg/day or less than 5 days, and no premedication, respectively. The accuracy of 99mTc-DISIDA scan in differentiating BA from NHS in group 1, 2, and 3 was 72.92 per cent, 89.66 per cent, and 100 per cent, respectively. No significant difference was seen between the patients who received and did not receive phenobarbital in terms of age at presentation, age at onset of jaundice, and liver function tests. In conclusion, phenobarbital therapy may not be necessary prior to 99mTc-DISIDA scan examination in the evaluation of cholestatic infants and thus a delay in diagnosis and surgical therapy of BA can be avoided.

Betamethasone in plus phenobarbitone prior to hepatobiliary scintigraphy increases diagnostic accuracy in infants with jaundice.

OBJECTIVE: In the diagnostic work up of the child with neonatal obstructive cholangiopathy (NOC), hepatobiliary scintigraphy (HBS) determines the need for peroperative cholangiography (POC). Traditionally, phenobarbitone is recommended to prime the liver to HBS. This retrospective study was designed to evaluate whether addition of the betamethasone (BM) alters the diagnostic accuracy of the HBS in distinguishing neonatal hepatitis (NH) from extra hepatic biliary atresia (EHBA). METHODS: Between 1993-1999, 202 patients presented with NOC and this study was not designed as a prospective randomized clinical trial. Of these, 126 patients had received Phenobarbitone (Group I) and the remaining 76 (Group II) had received BM in addition to the PB in a dose of 5 mg/k/d and 2.2 mg/k/d respectively for 7 days prior to HBS. RESULTS: Retrospective analysis revealed that, in the Group I, 41 showed excretion and 85 did not show any excretion of the radiopharmaceutical and the latter underwent POC which revealed that 31 patients (36%) of them showed patent biliary tract. In group II, 32 patients revealed excretion and 44 did not show any excretion of the radiopharmaceutical and the latter had undergone POC, which revealed that only 8 patients (18%) showed patent biliary tract. The percentages of false positives (36% vs 18%) was statistically significant (p < 0.03). CONCLUSION: Addition of BM increases the diagnostic accuracy of the HBS and this would lead to decreased need for POC to distinguish NH from EHBA.