Sudden and unexpected death of an infant in which an autopsy fails to identify the cause of death.

• A. Meningitis
• B. Neuropathy
• C. Sudden Infant Death Syndrome
• D. Congenital Heart Disease

Answer: (C)

SIDS is a diagnosis of exclusion for the sudden, unexpected death of an infant less than one year old when a complete investigation, including an autopsy, fails to identify a cause. The key idea is that no disease or abnormal finding explains the death after thorough testing, scene investigation, and history review. Meningitis would typically show infectious/inflammatory changes, congenital heart disease would usually be evident as a structural abnormality on autopsy or in the history, and neuropathy would involve identifiable nerve pathology. Because no cause is found despite a full workup, this scenario is classic for Sudden Infant Death Syndrome.