A 34-year-old man is brought to the emergency department in a resource-limited setting with severe agitation, hypersalivation, and extreme panic upon attempting to drink water. His wife reports that he was bitten on the right calf by a feral dog approximately six weeks ago, but he did not seek medical evaluation at the time. He is admitted to the intensive care unit but rapidly deteriorates and expires on hospital day 3.
Arrange the pathophysiologic events of this patient's infectious process in the correct chronological order, beginning from the initial inoculation to the eventual capacity for transmission.
- 1Binding of viral glycoproteins to nicotinic acetylcholine receptors at the neuromuscular junction
- 2Retrograde axonal transport toward the central nervous system via dynein molecular motors
- 3Viral replication within the perikaryon of motor neurons in the spinal cord
- 4Massive viral transcription in the hippocampus and cerebellum with formation of eosinophilic cytoplasmic inclusions
- 5Centrifugal anterograde spread along cranial nerves to the salivary gland acini
Answer
The correct pathophysiologic sequence of rabies infection begins with viral binding at the neuromuscular junction, followed by retrograde transport via dynein to the spinal cord, extensive replication in the brain (forming Negri bodies), and finally centrifugal spread to the salivary glands.
Rabies is a neurotropic virus that follows a strict anatomical and molecular sequence: local muscle replication -> binding to nAChRs -> retrograde transport via dynein -> replication in spinal cord/DRG -> massive brain replication (Negri bodies) -> centrifugal anterograde spread to salivary glands.
Step-by-Step Solution
Key Concept
Rabies virus pathogenesis and neurotropic dissemination
Estimated Time:1m 30s