Autopsy Pathology: Cause, Mechanism, and Manner
Cause, mechanism, manner-and the autopsy as audit
Autopsy questions test a triad and a process. Cause of death is the disease or injury that initiated the lethal sequence; mechanism is the physiologic derangement (arrhythmia, hemorrhage, sepsis); manner is natural, accident, homicide, suicide, or undetermined. Hospital autopsies require consent and emphasize clinicopathologic correlation; medicolegal cases belong to the medical examiner or coroner and may require chain of custody.
Know the classic evisceration approaches (Virchow, Rokitansky, Ghon, Letulle) as options rather than dogma; what matters is a complete, oriented examination with photography, organ weights, and targeted histology. Recognize postmortem change and artifact: livor, rigor, decomposition, resuscitation injury, and embalming. Consider toxicology, microbiology, and metabolic studies before fixation forecloses the opportunity.
Traps: recording “cardiac arrest” or “respiratory failure” as the cause; confusing a therapeutic complication with the underlying disease; overinterpreting postmortem cultures; missing a heritable cause in a young sudden death; and failing to examine the placenta in a fetal or neonatal death.
Rule of thumb: describe the findings, then explain the sequence. The cause must be a disease or injury-never a mechanism.
Worked example: a 34-year-old collapses and dies. Autopsy shows a dilated, thin-walled heart without coronary artery disease. This should raise concern for a genetic cardiomyopathy: retain frozen tissue for molecular testing, recommend family screening, and record the death as natural with an arrhythmic mechanism.