"Rabies encephalitis is a rapidly progressive CNS infection resulting from infection by a member of an RNA virus of the family Rhabdoviridae, genus Lyssavirus, most commonly transmitted to humans, from infected animal vectors, via a bite. It results in rapid neurological deterioration and, in almost all instances, progresses to death. Dominant imaging features are high T2 signal in the thalami, basal ganglia, brainstem and spinal cord."
"The word rabies has its origins in the Sanskrit root word 'rabhas', which means "violence" 2."
"Japanese encephalitis"
"Listeria rhombencephalitis"
Expected headings
"Classic rabies encephalitis"
"Paralytic rabies"
"Rabies encephalitis is a rapidly progressive CNS infection resulting from infection by a member of an RNA virus of the family Rhabdoviridae, genus Lyssavirus, most commonly transmitted to humans, from infected animal vectors, via a bite. It results in rapid neurological deterioration and, in almost all instances, progresses to death. Dominant imaging features are high T2 signal in the thalami, basal ganglia, brainstem and spinal cord."
"Involvement of the CNS by rabies can take two forms, which do not appear to correlate with the site of the bite, previous immunisation, vector (bat, dog or other) or any other clinical feature 1-3,5:"
"Encephalitis is by far the most common presentation of CNS involvement by rabies, accounting for 80% of cases. Symptoms are initially non-specific with general systemic symptoms, anorexia, irritability, inspiratory spasms and cough, autonomic dysfunction, and altered mental status 5. With time, classic symptoms and rabies encephalitis develop, including hydrophobia, aerophobia and hypersalivation, agitation and even priapism 1,2."
"Usually normal. Occasionally, non-specific hypoattenuation in the brainstem, mesial temporal lobes, basal ganglia and periventricular white matter may be evident 1,2. If imaging is only obtained late in the course of the disease, haemorrhage and cerebral swelling may be evident 1."
"herpes simplex encephalitis: greater predilection for mesial temporal lobes and insular cortex, with sparing of the basal ganglia, thalami and brainstem"
"classic rabies encephalitis (80%); equivalent to 'furious rabies' in dogs"
"paralytic rabies (20%); equivalent to 'dumb rabies' in dogs"
"Infection results most frequently from transmission of the virus from an infected animal to a human via a bite, as the virus is excreted into saliva 5. Occasionally, infection can also occur via an open wound, mucous membranes, inhalation, or, very rarely, as the result of corneal or organ transplantation (i.e. human-to-human transmission) or laboratory accidents 1,2,5."
"In classic rabies encephalitis, increased T2 signal has a predilection for the basal ganglia, thalami, hypothalami, brainstem, limbic system, and spinal cord, as well as the frontal and parietal lobes 1-3. In paralytic rabies, the involvement of the spinal cord and medulla is more pronounced, although no specific imaging features exist to allow differentiation from the classic encephalitic form 1,2."
"Unfortunately, once rabies encephalitis has manifested, there is no effective therapy available, and in nearly all cases, the disease results in a rapid decline of function, into coma and death 1,2,5. One treatment protocol has been developed, the "Milwaukee Protocol", however, its efficacy is questionable 5."