Objectives: To identify facial and biochemical characteristics as early clinical features of neonatal intrahepatic cholestasis due to citrin deficiency (NICCD).
Patients and methods: Ten patients with diagnoses of NICCD by SLC25A13 mutation analysis in Taiwan were recruited. A "Chubby Index" was developed for objective measurement of their facial characteristics. Liver function profiles were analyzed and compared with data on neonatal hepatitis and biliary atresia.
Results: Chubby face was observed in early infancy in all 5 patients whose serial photographs were taken. A significant difference in the Chubby Index was seen between NICCD infants and healthy infants (1.331 +/- 0.07 vs 1.068 +/- 0.059; P < 0.05). NICCD is characterized by an aspartate aminotransferase-to-alanine aminotransferase ratio of 2 or greater, a direct bilirubin-to-total bilirubin ratio under 0.67, and a standard deviation score for alpha-fetoprotein of 4 or greater, with respect to neonatal hepatitis and biliary atresia. Although chubby face, abnormal liver function profiles, and multiple amino acidemia gradually disappeared after age 1 year, an increase in hepatic echogenicity was observed in most patients in long-term follow-up.
Conclusions: Our Chubby Index is an informative measurement of the facial characteristics of infants with NICCD. The chubby face features, along with an aspartate aminotransferase-to-alanine aminotransferase ratio of 2 or greater, a direct bilirubin-to-total bilirubin ratio under 0.67, and a standard deviation score for alpha-fetoprotein of 4 or greater, may serve as useful clinical indicators for diagnosing NICCD early in infancy.