Cytosolic PEPCK deficiency (PCKDC) is a rare autosomal recessive inborn error of metabolism, which can present with hypoglycemia, lactic acidosis, and liver failure. It is caused by biallelic pathogenic variants in the PCK1 gene. Only four PCK1 variants have been previously reported in seven patients with PCKDC, and their clinical course of this condition has not been well characterized. Here, we report a Hispanic male with novel biallelic PCK1 variants, p.(Gly430Asp) and p.(His496Gln), who had a unique clinical presentation. He presented with a new onset of growth failure, elevated blood lactate, transaminitis, and abnormal urine metabolites profile, but he has not had documented hypoglycemia. Growth restriction happened due to insufficient caloric intake, and it was improved with nutritional intervention. PCKDC is a manageable disorder and therefore appropriate nutritional and clinical suspicion from typical lab abnormalities which lead to molecular confirmation tests are essential to prevent poor clinical outcomes.

胞质PEPCK缺乏症（PCKDC）是一种罕见的常染色体隐性先天性代谢错误，可伴有低血糖，乳酸性酸中毒和肝功能衰竭。它是由PCK1基因中的双等位基因致病变异引起的。先前在7名PCKDC患者中仅报道了4种PCK1变体，并且尚未对此疾病的临床过程进行很好的表征。在这里，我们报告一个西班牙裔男性，患有新型双等位基因PCK1p。（Gly430Asp）和p。（His496Gln）的变体，具有独特的临床表现。他出现了新的生长衰竭，血乳酸升高，氨氮炎和尿液代谢产物异常的发作，但他没有低血糖的记录。生长限制是由于热量摄入不足引起的，并且通过营养干预得以改善。PCKDC是一种可控制的疾病，因此对典型的实验室异常进行适当的营养和临床怀疑，导致进行分子确认试验对于预防不良的临床结果至关重要。