Objectives Type C pyruvate carboxylase (PC) deficiency is extremely rare, and has been described in only a few patients in literature to date. Herein, we present the case of a four-year-old patient admitted with diabetic ketoacidosis and diagnosed with type C PC deficiency based on clinical and biochemical findings. Case presentation A Turkish girl was referred to the intensive care unit at the age of three-years with a three-day history of vomiting and abdominal pain. Upon physical examination, the patient was found to be experiencing lethargy, dehydration, and Kussmaul breathing. Hyperglycemia, metabolic acidosis, and ketonemia were detected. Clinical and laboratory findings pointed to a prediagnosis of diabetic ketoacidosis. Intravenous fluid, bicarbonate, and insulin treatments were initiated. Elevated alanine and proline levels were recorded in plasma amino acid analysis, while urinary organic acid level analysis revealed increased lactate, pyruvate, 3-OH-butyrate, and acetoacetate levels. Whole exome sequencing revealed homozygous c.584C>T (p.Ala195Val) mutation in the PC gene. Conclusions To date, there have been no reports in literature of type C phenotype patients manifesting with DKA. Our case is the first case with the type C phenotype to be admitted with clinical and laboratory findings of DKA.

中文翻译：

---

C型丙酮酸羧化酶缺乏症作为糖尿病酮症酸中毒的鉴别诊断

目的 C 型丙酮酸羧化酶 (PC) 缺乏症极为罕见，迄今为止文献中仅在少数患者中进行了描述。在此，我们介绍了一名患有糖尿病酮症酸中毒并根据临床和生化发现诊断为 C 型 PC 缺乏症的四岁患者的案例。病例介绍 一名土耳其女孩在 3 岁时因呕吐和腹痛 3 天被转诊至重症监护室。体格检查后发现患者出现嗜睡、脱水和 Kussmaul 呼吸。检测到高血糖、代谢性酸中毒和酮血症。临床和实验室结果表明糖尿病酮症酸中毒的预诊断。开始静脉输液、碳酸氢盐和胰岛素治疗。在血浆氨基酸分析中记录了丙氨酸和脯氨酸水平升高，而尿液有机酸水平分析显示乳酸、丙酮酸、3-OH-丁酸和乙酰乙酸水平升高。全外显子组测序显示 PC 基因中存在纯合 c.584C>T (p.Ala195Val) 突变。结论 迄今为止，文献中未见有 C 型表型患者出现 DKA 的报道。我们的病例是第一个因 DKA 的临床和实验室检查结果而入院的 C 型表型病例。文献中未见 C 型表型患者出现 DKA 的报道。我们的病例是第一个因 DKA 的临床和实验室检查结果而入院的 C 型表型病例。文献中未见 C 型表型患者出现 DKA 的报道。我们的病例是第一个因 DKA 的临床和实验室检查结果而入院的 C 型表型病例。