An Unusual Case of Severe Anion Gap Metabolic Acidosis in a 3-year-old Girl.

1. Ryan M. Fredericks, MD*\n2. George Sam Wang, MD†\n3. Christine U. Vohwinkel, MD, PhD*\n4. Jessica Kraynik Graham, MD†\n\n\n \n\n1. *Children’s Hospital Colorado, Section of Pediatric Critical Care Medicine,\n\n2. †Section of Emergency Medicine, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO\n\n\n \n\n1. Address correspondence to Ryan M. Fredericks, MD, Heinrich A. Werner Division of Pediatric Critical Care Medicine, Kentucky Children\u0027s Hospital, 800 Rose St, MN 464-A, Lexington, KY 40536. E-mail: ryan.fredericks{at}uky.edu\n\nA 3-year-old previously healthy girl with normal development presents with 2 days of low-grade fevers, abdominal pain, nonbloody and nonbilious emesis occurring 6 to 7 times daily, and now tachypnea.\n\nAt an urgent care clinic, she is afebrile and normotensive with a heart rate of 127 beats/min, respiratory rate of 52 breaths/min, and oxygen saturation of 92% on room air. She weighs 1 kg less than her last recorded weight measured 2 months ago. On physical examination, she has dry mucous membranes, tachypnea, substernal retractions, and inferior abdominal tenderness. She is speaking slowly and her parents endorse that she seems slightly confused. They deny access to any medications or chemicals. Her newborn screens are normal. Family history is negative for consanguinity, genetic conditions, miscarriages, stillbirths, or early childhood deaths.\n\nLaboratory evaluation reveals a severe anion gap metabolic acidosis (AGMA) with appropriate respiratory compensation, (1) normal lactate, normoglycemia, and profound ketonemia (Table 1). A urine dipstick result is significant for hypersthenuria, ketonuria, and pH 5.5 but no glucosuria. Her measured serum osmolality is 299 mOsm/kg (299 mmol/kg), and her ammonia, albumin, homocysteine, and cobalamin levels are normal. Her complete blood cell count and hemoglobin A1c (HgbA1c) are normal, her respiratory pathogen and standard toxicology panels are negative, and her chest radiograph and abdominal ultrasound are without abnormalities. Further laboratory tests are sent to evaluate her severe AGMA including toxic alcohols, urinary organic acids (UOAs), serum amino acids (AAs), acylcarnitines, and a carnitine panel.\n\nView this table:\n\nTABLE 1. \nLaboratory Data\n\n\n\nThe girl is admitted to the PICU at a quaternary care center after receiving 20 mL/kg of normal saline, ondansetron, and ketorolac without improvement …