GSS initially diagnosed as conversion disorder
Date of birth: 1981-01-01
Gender: Female
A woman first presented to neurology in January 2019 with intermittent tremor, dysarthria and psychomotor slowing. Brain MRI, EEG and lumbar puncture were unremarkable, and conversion disorder was diagnosed. Over the following years she developed progressive speech impairment, gait disturbance, recurrent falls, cognitive deficits and objective abnormalities on imaging, EEG and neuropsychological testing. In January 2023, molecular genetic testing identified a heterozygous nine-octapeptide-repeat insertion in PRNP, also present in her father, confirming Gerstmann–Sträussler–Scheinker disease (GSS). https://pmc.ncbi.nlm.nih.gov/articles/PMC12670835/
Symptoms
Intermittent tremor
Dysarthria / speech disturbance
Psychomotor slowing / bradykinesia
Word-finding difficulty
Difficulty constructing sentences
Memory impairment
Concentration impairment
Executive dysfunction
Confusion
Disorientation
Gait disturbance / instability
Severe imbalance
Recurrent falls
Reduced strength in all four limbs
Postural tremor
Resting tremor
Stereotyped upper-limb movements
Positive Romberg sign
Agitation
Restlessness
Irritability
Mood swings / emotional instability
Reduced emotional expressiveness
Failure to recognize family members
Severe insomnia / sleep disturbance
Nocturnal restlessness
Family history
- Father: developed a similar constellation of symptoms and died prematurely at a relatively young age.
- Paternal grandmother: also developed similar symptoms and died prematurely at a relatively young age.
- Patient: only child, no siblings.
- Genetic testing subsequently showed that both the patient and her father carried the heterozygous 9-OPRI insertion in the PRNP gene