Sudden infant death syndrome

Last updated: Saturday, 14, August, 2010

Key Information	Appropriate Tests
Defined as the sudden and unexpected death of an infant under one year of age, with onset of the lethal episode apparently occurring during sleep, that remains unexplained after a thorough investigation including performance of a complete autopsy, and review of the circumstances of death and the clinical history (San Diego 2004). Predisposing and risk factors include Prone sleeping position Cigarette smoke exposure Overheating Head covering Low socioeconomic status Prematurity Intrauterine growth retardation Maternal drug use Young maternal age Multiparity	Autopsy should be performed by a paediatric or forensic pathologists and should conform to recognised national or international protocols. Investigations include diagnostic imaging (e.g. a full skeletal survey), toxicology; bacteriologic, virologic, electrolyte and metabolic studies.
Differential Diagnosis for Unexpected Infant and Early Childhood Death
NATURAL
Infection	Cardiovascular: myocarditis, endocarditis, rheumatic fever, aortitis Respiratory: acute epiglottitis, acute bronchopneumonia Central nervous system: meningitis, encephalitis, poliomyelitis Haematologic: malaria, infectious mononucleosis Gastrointestinal: gastroenteritis, botulism Genitourinary: pyelonephritis Generalized: septicaemia, endotoxaemia
Cardiac	Infections Congential cardiac defects (before and after surgery) Cardiomyopathies Valvular abnormalities: aortic stenosis, mitral valve prolapse syndrome, tricuspid valve prolapse Subaortic stenosis Tumors Conduction defects Miscellaneous: endocardial fibroelastosis
Vascular	Aortic abnormalities: supravalvular stenosis, coarctation, William syndrome, DiGeorge syndrome Coronary artery abnormalities: anomalous coronary arteries, aplasia/hypoplasia, idiopathic arterial calcinosis, coronary arteritis (Kawasaki disease) Venous abnormalities: total anomalous pulmonary venous drainage Vascular malformations Pulmonary hypertension Miscellaneous: fibromuscular dysplasia, aortic cystic medial necrosis, Budd-Chiari syndrome, thromboembolism
Respiratory	Infections Upper airway obstruction Asthma Bronchopulmonary dysplasia Miscellaneous: massive pulmonary haemmorrhage, idiopathic pulmonary haemosiderosis, tension pneumothorax
Central Nervous System	Infections Epilepsy Haemorrhage: bleeding diatheses, vascular malformations Tumours Metabolic Disorders Structural Abnormalities Miscellaneous: Moyamoya disease, fibromuscular dysplasia, Friedreich ataxia, tuberous sclerosis, von Recklinghausen disease, Guillain-Barre syndrome
Haematological	Haemoglobinopathies: sickle cell disease Malignancies: lymphoma, leukaemia Bleeding diatheses Anaemia Miscellaneous: infections, polycthaemia, splenic disorders
Gastrointestinal	Infections: gastroenteritis Intestinal obstruction: intussusception, volvulus Intestinal perforation Gastro-oesophageal reflux/aspiration Late-presenting congenital diaphragmatic hernia Gastrointestinal haemorrhage Miscellaneous: cystic fibrosis, pancreatitis, anorexia nervosa/malnutrition
Genitourinary	Primary renal disease: pyelonephritis, glomerulonephritis Urinary tract obstruction Wilms tumour Miscellaneous: haemolytic uraemic syndrome
Metabolic	Reye syndrome Fatty acid oxidation defects: Acyl-CoA dehydrogenase deficiencies (MCAD, LCAD) Carbohydrate disorders: galactosemia, glycogen storage diseases Amino acid disorders: homocystinuria Urea cycle disorders Organic acid disorders
Endocrine	Congenital adrenal hyperplasia Diabetes mellitus Thyroid disease
Miscellaneous	Connective tissue disorders: Marfan syndrome, Ehlers-Danlos syndrome type IV Chromosomal disorders: trisomy 21 Skeletal disorders: achondroplasia Dermatological disorders: hypohydrotic ectodermal dysplasia Muscular conditions: malignant hyperthermia Immunological conditions: anaphylaxis
UNNATURAL
Accidental
Nonaccidental
References	1. Byard RW, Krous HF, Sudden infant death syndrome - overview and update. Pediatr Develop Pathol 2003; 6: 112-127 2. Byard RW, Sudden Death in Infancy, Childhood and Adolescence, Cambridge University Press, Cambridge, 2nd Edition, 2004. 3. Byard RW, Krous HF, Sudden natural infant and childhood death. In: Encyclopedia of Forensic and Legal Medicine, Eds. Payne-James J, Byard RW, Corey T, Henderson C. Elsevier/Academic Press, Amsterdam Vol. 1. pp 382-391, 2005.