Twelve cases (one Gerstmann-Sträussler-Scheinker syndrome (P102L; definite), one genetic
Creutzfeldt-Jakob disease (CJD) (V180I; definite) and ten
sporadic CJD (7 MM1-type definite, 3 probable)), who reached the
akinetic mutism state, were investigated with regard to their
clinical course and treatment. They were hospitalized for a total of 3,968 days in the
akinetic mutism state. In the nine definite cases, the median period from the
akinetic mutism state to death was 22 months (average: 27.0 ± 23.3 months, range: 3-80 months) and median total disease duration was 27 months (average: 34.2 ± 30.1 months, range: 5-102 months). In the seven definite
sporadic CJD cases, the median period from
akinetic mutism to death was 21 months (average: 17.0 ± 9.6 months, range 3-28 months), and median total disease duration was 24 months (average: 20.6 ± 10.0 months, range: 5-31 months). Nasal-
tube feeding was performed in all cases. Symptomatic treatments such as
parenteral nutrition and
antibiotic drugs were administered for complications such as respitory and
urinary tract infections and digestive symptoms. Patients received rehabilitation and hot spring
therapy regularly until death.
Gastrostomy and/or
tracheotomy was not performed in any case, the patients were not intubated nor was
mechanical ventilation (including non-invasive
positive pressure ventilation) applied. Vasoactive drugs were not administered.
Clonazepam was administered for
myoclonus in four patients but not in another three when
myoclonus appeared. It is unclear whether the treatment influenced the duration of
myoclonus. Our observations indicate that the extended survival period among Japanese
prion disease patients is likely due to the management procedures implemented for
prion disease in Japan, which are usually continued after the patients reach the
akinetic mutism state. We speculate that nasal-
tube feeding is the crucial factor that results in the prolonged disease duration of
prion disease patients in the
akinetic mutism state.