Differential Diagnosis of Jakob-Creutzfeldt Disease
Posted Oct 05 2012 8:37pm
Original Contribution| ONLINE FIRST
Differential Diagnosis of Jakob-Creutzfeldt Disease
Ross W. Paterson, MRCP; Charles C. Torres-Chae, MPA; Amy L. Kuo, MS, RN, GNP; Tim Ando, BA; Elizabeth A. Nguyen, BS; Katherine Wong, BS; Stephen J. DeArmond, MD, PhD; Aissa Haman, MD; Paul Garcia, MD; David Y. Johnson; Bruce L. Miller, MD; Michael D. Geschwind, MD, PhD Arch Neurol. 2012;():1-5. doi:10.1001/archneurol.2013.79. Text Size: AA A Published online September 24, 2012 ABSTRACT
Objectives To identify the misdiagnoses of patients with sporadic Jakob-Creutzfeldt disease (sCJD) during the course of their disease and determine which medical specialties saw patients with sCJD prior to the correct diagnosis being made and at what point in the disease course a correct diagnosis was made.
Design Retrospective medical record review.
Setting A specialty referral center of a tertiary academic medical center.
Participants One hundred sixty-three serial patients over a 5.5-year period who ultimately had pathologically proven sCJD. The study used the subset of 97 patients for whom we had adequate medical records.
Main Outcome Measures Other diagnoses considered in the differential diagnosis and types of medical specialties assessing patients with sCJD.
Results Ninety-seven subjects' records were used in the final analysis. The most common disease categories of misdiagnosis were neurodegenerative, autoimmune/paraneoplastic, infectious, and toxic/metabolic disorders. The most common individual misdiagnoses were viral encephalitis, paraneoplastic disorder, depression, vertigo, Alzheimer disease, stroke, unspecified dementia, central nervous system vasculitis, peripheral neuropathy, and Hashimoto encephalopathy. The physicians who most commonly made these misdiagnoses were primary care physicians and neurologists; in the 18% of patients who were diagnosed correctly at their first assessment, the diagnosis was almost always by a neurologist. The mean time from onset to diagnosis was 7.9 months, an average of two-thirds of the way through their disease course.
Conclusions Diagnosis of sCJD is quite delayed. When evaluating patients with rapidly progressive dementia with suspected neurodegenerative, autoimmune, infectious, or toxic/metabolic etiology, sCJD should also be included in the differential diagnosis, and appropriate diagnostic tests, such as diffusion brain magnetic resonance imaging, should be considered. Primary care physicians and neurologists need improved training in sCJD diagnosis.
PO-028: Oral transmission of L-type bovine spongiform encephalopathy (L-BSE) in primate model Microcebus murinus
Nadine Mestre-Frances,1 Simon Nicot,2 Sylvie Rouland,1 Anne-Gaëlle Biacabe,2 Isabelle Quadrio,3 Armand Perret-Liaudet,3 Thierry Baron,2 Jean-Michel Verdier1 1IN SER M UM2; Montpellier, France; 2Anses; Lyon, France; 3Hopitaux Civils de Lyon; Lyon, France
An atypical form of bovine spongiform encephalopathy has been identified in cattle in Europe, North America and Japan and was designed as L-type BSE (L-BSE) due to the lower apparent molecular mass of the unglycosylated, protease-
resistant prion protein (PrPres) detected by western blot compared with classical BSE. Experimental evidences from studies in transgenic mice expressing human PrP and in primate models suggest a higher risk of transmission to humans of the L-BSE form than for classical BSE agent. However, a major unresolved issue concerns the potential transmissibility of the L-BSE agent by oral route. To address this question, we infected mouse lemurs (Microcebus murinus), a non-human primate model, with L-BSE by intracerebral or oral route.
Four adult lemurs were intracerebrally (IC) inoculated with 5mg of L-BSE infected brain homogenate of an atypical French BSE case (02-2528). Four young and four adult animals were fed with 5 mg or 50 mg of infected brain. After sacrifice, the brain tissues were biochemically and immunocytochemically investigated for PrPres.
The 4 animals IC inoculated died at 19 and 22 months postinoculation (mpi). They developed blindness, tremor, abnormal posture, incoordinated movements, balance loss. Symptoms get worse according to the disease progression, until severe ataxia. Severe spongiosis was evidenced into the thalamus, the striatum, the mesencephalon, and the brainstem, whereas into the cortex the vacuolisation was weaker. Strong deposits of PrPres were detected into the thalamus, the striatum, and the hippocampus whereas in the cerebral cortex, PrPres was prominently accumulated in plaques.
The orally inoculated animals showed similar clinical symptoms occurring between 27 and 34 mpi. Disease was characterized by progressive prostration, loss of appetite and poor appearance of the fur. Only one adult animal showed disequilibrium. PrPres was strongly accumulated only in the striatum and thalamus and weakly into the cortex. No plaques were evidenced. Two animals that were orally challenged at the age of two years are still alive and healthy 34 months after inoculation. The western blot analysis showed uniform molecular profiles, irrespective of the route or dose of infection, and included notably a PrPres form with low apparent molecular mass (~19 kDa) similar to the PrPres in the original cattle brain. However, the PrPres profile in lemurs was characterized by a higher proportion of di- and mono-glycosylated species (up to 95% of the total signal) than in the bovine L-BSE inoculum (~80%). In addition, small amounts of PrPres were detected by western blotting in the spleen of three animals (one intra-cerebrally inoculated and two fed with 5 mg of cattle brain).
Here, we demonstrate that the L-BSE agent can be transmitted by oral route from cattle to young and adult mouse lemurs. In comparison to IC inoculated animals, orally challenged lemurs were characterized by longer survival periods as expected with this route of infection.
EFSA Journal 2011 The European Response to BSE: A Success Story
EFSA and the European Centre for Disease Prevention and Control (ECDC) recently delivered a scientific opinion on any possible epidemiological or molecular association between TSEs in animals and humans (EFSA Panel on Biological Hazards (BIOHAZ) and ECDC, 2011). This opinion confirmed Classical BSE prions as the only TSE agents demonstrated to be zoonotic so far but the possibility that a small proportion of human cases so far classified as "sporadic" CJD are of zoonotic origin could not be excluded. Moreover, transmission experiments to non-human primates suggest that some TSE agents in addition to Classical BSE prions in cattle (namely L-type Atypical BSE, Classical BSE in sheep, transmissible mink encephalopathy (TME) and chronic wasting disease (CWD) agents) might have zoonotic potential.
Are USDA assurances on mad cow case 'gross oversimplification'?
What irks many scientists is the USDA’s April 25 statement that the rare disease is “not generally associated with an animal consuming infected feed.”
The USDA’s conclusion is a “gross oversimplification,” said Dr. Paul Brown, one of the world’s experts on this type of disease who retired recently from the National Institutes of Health. "(The agency) has no foundation on which to base that statement.”
“We can’t say it’s not feed related,” agreed Dr. Linda Detwiler, an official with the USDA during the Clinton Administration now at Mississippi State.
In the May 1 email to me, USDA’s Cole backed off a bit. “No one knows the origins of atypical cases of BSE,” she said
The argument about feed is critical because if feed is the cause, not a spontaneous mutation, the California cow could be part of a larger outbreak.