Infectious diseases Bacterial sepsis a Meningitis a Urinary tract infection a Viral infections—enterovirus, respiratory syncytial virus, herpes simplex a Pertussis Congenital syphilis Omphalitis Cardiac disease Congenital heart disease a Supraventricular tachycardia a Myocardial infarction (most commonly aberrant left coronary artery) Pericarditis Myocarditis Kawasaki disease Endocrine disorders Congenital adrenal hyperplasia Metabolic disorders Hyponatremia, hypernatremia a Cystic fibrosis Inborn errors of metabolism, galactosemia Hypoglycemia a Drugs/toxins—aspirin, carbon monoxide Renal disorders Posterior urethral valves Hematologic disorders Severe anemia a Methemoglobinemia Kernicterus Gastrointestinal disorders Gastroenteritis with dehydration a Pyloric stenosis a Intussusception