Background: Idiopathic ketotic hypoglycemia (IKH) is the most common etiology of hypoglycemia in the 1-5 year age group. Even in its typical presentation, workup of this self limited condition is often overzealous and expensive. Objectivas: To determine, in a population seen at The Children's Hospital of Alabama (TCHA), 1. the prevalence of hypoglycemia, 2. the prevalence of IKH, 3. IKH patient demographics, and 4. presenting laboratory data, including the yield and cost of ordered tests. Method?: Retrospective review of medical records of patients 1-5 years of age with primary or secondary diagnosis of hypoglycemia (ICD-9 code 251.2), seen at TCHA between 1/92 and 8/95. Results: 30 patients were identified. Mean blood glucose (BG) was 34.2 mg/dL. Prevalence of hypoglycemia presenting to the ED was 5/100,000.18 patients were diagnosed with IKH, for a prevalence of 3/100,000. The other diagnoses included: IDDM with hypoglycemic reaction (3), sepsis (2), glycogen storage disease (2), fatty acid oxidation defect (2), suspected ingestion (1), nesidioblastosis (1), & ketotic hypoglycemia, inconclusive (1). Of the 18 IKH patients, demographics were : mean age, 27.7 months; 12 males, 6 females; 8 white, 9 black (1 not available). S patients' weights were < 25%ile. 14 of 18 IKH patients bad insulin (cost = $40), growth hormone (GH, $69), and cortUisol ($54) levels drawn. All 14 had appropriately low insulin levels (
22 μg/dL). S had GH < 5ng/ml, 7 had GH > 5ng/ml & 5 were not done. 4 IKH patients had urine drug screens ($280); all were negative. Though no IKH patients were febrile, 6 had sepsis workups($380), all culture-negative. Urine ketones were > 3+ in 8 of 15 patients tested. Mean anion gap was 20 (range: 16-31). 8 of 18 IKH patients were discharged from the ED after return to normal status. Conclusions: A clinical picture typical for IKH (1-5 year-old, previously healthy, normal growth & development, symptomatic fasting hypoglycemia with ketonuria, no hepatomegaly & resolution with glucose) warrants no further workup. Serum collected at the time of hypoglycemia may obviate the need for fasting studies at a later date, if so indicated. Additional tests in our population did not add to diagnostic yield yet added $352.00 in costs per patient.