Introduction: In Serbia and Montenegro postexposure rabies vaccination is performed using five doses of rabies vaccine with a potency of 2.5 I.U. It is given on 0, 3rd, 7th, 14th and 28th day, combined with human rabies immunoglobulin with the first dose. Modern rabies vaccines produced in cell cultures rarely cause neurologic complications, among which Guillain-Barre syndrome and parkinsonism.
Case report: The authors report a case of a 78-year-old woman with a documented five-year history of Parkinson's disease, who was bitten by a rabid cat. Twelve hours later, when the rabies infection of the cat was confirmed by an immunofluorescence test, the patient received the first dose of rabies vaccine Verorab (Aventis), a cell culture vaccine, together with the human rabies immunoglobulin produced in Belgrade. After the third dose of rabies vaccine, the symptoms of Parkinson's disease progressed and vaccination was interrupted. However, one month later, the patient died with predominantly neurological symptoms. As the patient died at the time when incubation of rabies might have been expected, autopsy and rabies diagnostics were performed. AUTOPSY AND PATHOHISTOLOGIC FINDINGS: The autopsy and pathohistologic findings from the specimens treated with routine hematoxylin and eosin staining, together with immunofluorescence test, excluded rabies as a cause of death and revealed neurodegenerative changes typical for Parkinson's disease. Using two different fluorescent rabies antibodies, we performed a direct immunofluorescence antibody tests, but no rabies antigens were detected. However, in histologic slides of the brain stem, large intracytoplasmic inclusions were found in some neurons, identified as Lewy bodies characteristic for Parkinson's disease.
Conclusion: Parkinson's disease, with its complications, was the cause of death of the patient bitten by a rabid cat. Furthermore, the coincidence of the progression of Parkinson's disease symptoms, at the time of postexposure rabies vaccination, points to the vaccine as a possible contributing factor to aggravation of the disease and lethal outcome.