Congenital bile acid synthesis defect type 3 is a rare metabolic liver disease with only eight patients reported in literature. We describe clinical, pathological and molecular features for a ninth patient. A 4-month-old infant presented to us with conjugated hyperbilirubinemia. His liver biopsy revealed giant cell change, steatosis, and activity with diffuse fibrosis. Immunostaining with bile salt export pump showed preserved canalicular pattern and γ-glutamyl transferase 1 staining showed unusual complete membranous pattern. Genetic workup revealed homozygous single base pair duplication in exon 3 of the CYP7B1 gene. He succumbed to liver disease at 7 months of age.

中文翻译：

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先天性胆汁酸合成缺陷 3 型伴有严重的新生儿胆汁淤积。

先天性胆汁酸合成缺陷 3 型是一种罕见的代谢性肝病，文献中仅报道了 8 例患者。我们描述了第九名患者的临床、病理和分子特征。一名 4 个月大的婴儿出现结合高胆红素血症。他的肝活检显示巨细胞改变、脂肪变性和活动性弥漫性纤维化。胆盐输出泵免疫染色显示保留的小管模式，γ-谷氨酰转移酶 1 染色显示不寻常的完整膜模式。基因检查显示 CYP7B1 基因的外显子 3 中存在纯合单碱基对重复。他在 7 个月大时死于肝病。