Laboratory investigations of hypoglycemia depend on many tests: plasma glucose is usually <55-70 mg/dL, insulin, c-peptide, proinsulin, sulfonylurea screen, beta-hydroxybutyrate, and 24-hour fasting glucose level are another tests that are required to establish the etiology.
Hypoglycemia laboratory findings
Metabolic syndrome laboratory findings
Diabetes mellitus type 1 laboratory findings
Hypoglycemia echocardiography or ultrasound
Diabetic ketoacidosis laboratory findings
Diabetes mellitus type 2 laboratory findings
Hyperosmolar hyperglycemic state laboratory findings
Euthyroid sick syndrome laboratory findings