Kanchan Kumari1, Gabriella Rizzo1, Daniel Zhou1, Kaeli Samson1, Daniel Murman1
1University of Nebraska Medical Center
Objective:
To describe factors leading to delay in diagnosis of CJD.
Background:
Creutzfeldt Jakob Disease (CJD) is a rare prion disease that causes rapidly progressive dementia (RPD) and is always fatal. CJD can be challenging to diagnose, sharing clinical features with other forms of dementia and various encephalopathies.
Design/Methods:
With IRB approval, we reviewed medical records of patients diagnosed with definitive or probable CJD from 1/1/2012 to 12/31/2022 admitted at our tertiary care hospital. We extracted demographic, clinical, and imaging data and analyzed their relationships based on time to Real-Time Quaking-Induced Conversion (RT-QuIC) testing and a CJD diagnosis.
Results:
We identified 25 patients who met the above criteria. Only 4 received brain biopsy, while other 21 had probable CJD. The median time from initial medical presentation to documented suspicion for RPD was 47 days (IQR: 16, 104) and to RT-QuIC result was 89 days (IQR: 35, 133). On first MRI and EEG, 70% patients had diffusion restriction, 26% patients had periodic sharp wave complexes. 28% and 25% of patients received ≥3 brain MRI scans and ≥3 EEG studies, respectively. presented with predominant psychiatric presentation, comorbidities, and lab abnormalities suggestive of toxic-metabolic encephalopathy or weakly positive autoantibodies had delay in CJD diagnosis. When comparing patient’s gender, age, or individual myoclonic, cerebellar, or extrapyramidal symptoms on initial presentation in relation to time to RT-QuIC testing, there were no significant differences. Mean time for rural residents (n = 9) to RT-QuIC was 44.14 days (SD: 33.84) versus for urbanites (n = 16) with 158.58 days (SD: 216.91) (p=0.09).
Conclusions:
Diagnostic yield was higher when LP was performed over repeat ancillary testing, preferentially supporting LP when clinicians suspect an unusual diagnosis. Delays in diagnosis of CJD are likely due to confounding data suggesting a different diagnosis.