Case Presentation: A 69 year old gentleman with benign essential tremor presented with one month duration of progressive cognitive decline and confusion. One month prior, the patient was a fully functional dentist who partook in recreation deer hunting. The patient quickly demonstrated marked personality changes, short term memory loss and jerking myoclonus with tremulousness. Family members denied recent travel, or antecedent fevers, neck stiffness or headache. No family history of heritable neurological conditions were reported. Following hospitalization for altered mental status, the clinical course decompensated quickly and the patient required intubation for airway protection. An extensive metabolic and infectious work up was unrevealing. A lumbar puncture showed CSF cell count 2, protein 85, glucose 59 and negative bacterial and viral cultures. Review of brain and brainstem MRI suggested cortical ribboning on diffusion weighted images in both the right and left hemispheres. EEG showed semi-rhythmic background slowing. Neuronal nuclear Hu antibody for autoimmune encephalitis was negative. A therapeutic trial of intravenous immunoglobulin was terminated after two days as the family elected for transition to comfort measures. CSF studies previously sent to the National Prion Disease Center for RT-QulC, 14-3-3, and T-tau returned elevated after the patient had unfortunately expired.
Discussion: We present an interesting case of rapidly progressive Creutzfeldt Jacob Disease (CJD) aided in diagnosis by newly described CSF testing. Wider recognition of diagnostic tools now available facilitates earlier diagnosis which could help guide any potential therapeutic intervention. We suspect possible prion exposure in our patient that could have occurred in several settings: a forensic dentistry laboratory with human CSF samples or to recreational Southern California deer hunting among which the population is known to harbor disease. This case also illustrates an extremely uncommon condition for which early suspicion and diagnosis guide prognostication as no curative treatments exist to date. Early hospice care is often necessary. The reported incidence of CJD is 1 case per million worldwide and the advent of improved imaging and specific CSF tests can improve prognostication for end of life planning. Our clinical suspicion for CJD was strengthened with findings of cortical ribbons on MRI which were considered in this clinical context, but not described on the official radiographic report. This demonstrates the additional value of imaging in building the diagnosis of CJD. It is educational to note that CSF is 98% specific if positive for CJD, but the gold standard nonetheless remains autopsy with brain biopsy.
Conclusions: In addition to clinical findings, the diagnostic tools aid in earlier recognition include novel real-time quaking induced conversion (RT-QulC) and MRI brain scan as non-invasive adjunctive tests to post-mortem brain biopsy. Clinicians who suspect CJD should consider diagnostics with novel CSF proteins and imaging in this rapidly devastating condition to also assist in prognostication. Early confirmation of the condition can allow for a multi-disciplinary team to support caregivers and family members at end of life.
