620-P: Novel Case of Diabetes Mellitus with VLCAD Deficiency

Abstract

Objective: To present a novel case of diabetes mellitus (DM) with hypertriglyceridemia in a patient with Very Long Chain Acyl-Coenzyme A Dehydrogenase (VLCAD) Deficiency. Case: A 37 year old man presented to ER with nausea, emesis, and abdominal pain. He also noted polyuria, polydipsia, and 23 pounds weight loss in the prior 2 weeks, during a rehab program for cocaine abuse. He reported non-adherence to very high carbohydrate, low fat diet prescribed for VLCAD Deficiency, myopathic episodic form. Labs on admission revealed Na 123 mmol/L, K 6.0 mmol/L, BG 1,065 mg/dL, Anion Gap 12 mmol/L, pH 7.377, Triglycerides 2,281 mg/dL, Lipase 46 IU/L, CK 326 IU/L, Urine negative for ketones, Serum Beta-Hydroxybutyrate 0.62 mmol/L, Serum Osmolality 337 mOsm/kg, and HbA1c 13.5%. IV insulin and IVF were used to treat hyperglycemia and hypertriglyceridemia. CK levels remained stable. He was transitioned off IV insulin to subcutaneous insulin once TGL<1000 mg/dL. Discussion: VLCAD Deficiency is a rare autosomal recessive disease that disables the breakdown of long-chain fatty acids into energy, which can be a significant issue during times of fasting. It is treated primarily with dietary modifications consisting of a high carbohydrate, low fat diet. Prolonged fasting is not recommended in this condition, to avoid risk of rhabdomyolysis. Given these concerns, caution was exercised to avoid hypoglycemia by adding dextrose to IV fluids and initiating complex carb diet thereafter. DM has been reported to occur in patients with medium-chain acyl-coenzyme A dehydrogenase deficiency, but to our knowledge, has not been described in VLCAD Deficiency in literature. In this case, the diagnosis of DM was established in the setting of elevated triglycerides and deviation from prescribed diet. Ketones were low, likely owing to limited fatty acid oxidation. GAD Antibody was undetectable and Tetradecenoylcarnitine, C14:1 elevated to 4.37 was consistent with deficiency of VLCAD. Further investigations will be pursued to determine potential underlying mechanism. Disclosure C.E. Price: None. K. Mekala: None. K. Favreau: None.