Rare V180I mutation in PRNP gene of a Chinese patient with Creutzfeldt-Jakob disease

A systemic analysis of Creutzfeldt Jakob disease cases in Asia

Creutzfeldt Jakob Disease (CJD) is a rapidly progressive, fatal neurodegenerative disorder, also known as a subacute spongiform encephalopathy. There are three major subtypes of CJD i.e. Sporadic CJD, which occurs for reasons unbeknown to science (85% of known cases), Genetic or Familial CJD which is characterized by the presence of mutations in the human prion protein (PRNP) gene (10-15% cases) and Iatrogenic CJD that occurs via accidental transmission through medical and surgical procedures (1-2% cases). CJD cases occur globally with 1 case per one million population/year. Considerable data is available related to the incidence and prevalence of CJD in Europe and America. However, the global surveillance database is yet to include Asia even though several Asian countries have their own CJD monitoring units. sCJD is the highest among all CJD cases in Asia. China (1957) and Japan (1705) have reported more cases of sCJD than any Asian country and Hong Kong (1) has reported the least. On the other hand, gCJD is highest in Japan (370) and least in India (2). Our analysis establishes the presence of all variants of CJD across Asia. However, in most Asian countries in general and Southeast Asian countries in particular, CJD cases are misdiagnosed and often underreported. Since Asia is the most populated continent in the world, the actual global prevalence of CJD cannot be estimated until and unless these countries are accounted for. Concrete and reliable surveillance networks are needed across Asia to evaluate the prevalence and incidence of CJD in the region. [Figure: see text]The graphical abstract demonstrates the prevalence of CJD cases in the world and systematically analyses the incidence of CJD in Asian countries between the year 1986-2022. Highest number of cases were reported in Japan followed by China. The study emphasizes the need for assimilation of Asian data in global prevalence.

Neutrophil to High-density Lipoprotein ratio (NHR) as a potential predictor of disease severity and survival time in Creutzfeldt-Jakob disease

INTRODUCTION

Creutzfeldt-Jakob disease (CJD) is a fatal and irreversible neurodegenerative disease. Identification of inexpensive and easy-to-implement biomarkers of CJD which could predict disease severity and patient survival is important for improving disease management. The aim of this study was to assess the predictive value of peripheral neutrophil to lymphocyte ratio (NLR), high-density lipoprotein (HDL), monocyte to HDL ratio (MHR) and neutrophil to HDL ratio (NHR) for CJD.

METHODS

Patients with definite or probable CJD admitted to the Neurology Department of Xuanwu Hospital from 2014 to 2021 were enrolled and followed up until April 2022. Clinical information including sex, age, Barth Index, survival time and results of auxiliary examination were collected, and NLR, HDL, NHR and MHR were measured for all enrolled patients. The associations between NLR, HDL, NHR and MHR, and disease severity (evaluated by Barth Index), survival time and auxiliary examinations were evaluated.

RESULTS

A total of 88 CJD patients were enrolled and all were deceased. NLR (r = -0.341, p = 0.001), NHR (r = -0.346, p = 0.001) and MHR (r = -0.327, p = 0.002) were significantly associated with disease severity. Higher NHR (HR = 2.344, 95% CI = 1.277-4.303 p = 0.006) and lower HDL (HR = 0.567, 95% CI = 0.346-0.930, p = 0.025) were associated with shorter survival time in the CJD patients.

CONCLUSIONS

Peripheral inflammatory biomarkers, especially NHR, were associated with disease severity and survival duration. These findings provide new insights into the mechanisms and treatment strategies of CJD.

Prion Mutations in Republic of Republic of Korea, China, and Japan

Prion gene (PRNP) mutations are associated with diverse disease phenotypes, including familiar Creutzfeldt-Jakob Disease (CJD), Gerstmann-Sträussler-Scheinker disease (GSS), and fatal familial insomnia (FFI). Interestingly, PRNP mutations have been reported in patients diagnosed with Alzheimer's disease, dementia with Lewy bodies, Parkinson's disease, and frontotemporal dementia. In this review, we describe prion mutations in Asian countries, including Republic of Republic of Korea, China, and Japan. Clinical phenotypes and imaging data related to these mutations have also been introduced in detail. Several prion mutations are specific to Asians and have rarely been reported in countries outside Asia. For example, PRNP V180I and M232R, which are rare in other countries, are frequently detected in Republic of Korea and Japan. PRNP T188K is common in China, and E200K is significantly more common among Libyan Jews in Israel. The A117V mutation has not been detected in any Asian population, although it is commonly reported among European GSS patients. In addition, V210I or octapeptide insertion is common among European CJD patients, but relatively rare among Asian patients. The reason for these differences may be geographical or ethical isolation. In terms of clinical phenotypes, V180I, P102L, and E200K present diverse clinical symptoms with disease duration, which could be due to other genetic and environmental influences. For example, rs189305274 in the ACO1 gene may be associated with neuroprotective effects in cases of V180I mutation, leading to longer disease survival. Additional neuroprotective variants may be possible in cases featuring the E200K mutation, such as KLKB1, KARS, NRXN2, LAMA3, or CYP4X1. E219K has been suggested to modify the disease course in cases featuring the P102L mutation, as it may result in the absence of prion protein-positive plaques in tissue stained with Congo red. However, these studies analyzed only a few patients and may be too preliminary. The findings need to be verified in studies with larger sample sizes or in other populations. It would be interesting to probe additional genetic factors that cause disease progression or act as neuroprotective factors. Further studies are needed on genetic modifiers working with prions and alterations from mutations.

Systematic Review of Clinical and Pathophysiological Features of Genetic Creutzfeldt-Jakob Disease Caused by a Val-to-Ile Mutation at Codon 180 in the Prion Protein Gene

Genetic Creutzfeldt-Jakob disease (gCJD) is a subtype of genetic prion diseases (gPrDs) caused by the accumulation of mutated pathological prion proteins (PrPSc). gCJD has a phenotypic similarity with sporadic CJD (sCJD). In Japan, gCJD with a Val to Ile substitution at codon 180 (V180I-gCJD) is the most frequent gPrD, while the mutation is extremely rare in countries other than Japan and Korea. In this article, we aim to review previously elucidated clinical and biochemical features of V180I-gCJD, expecting to advance the understanding of this unique subtype in gCJD. Compared to classical sCJD, specific clinical features of V180I-gCJD include older age at onset, a relatively slow progression of dementia, and a lower positivity for developing myoclonus, cerebellar, pyramidal signs, and visual disturbance. Diffuse edematous ribboning hyperintensity of the cerebral cortex, without occipital lobes in diffusion-weighted magnetic resonance imaging, is also specific. Laboratory data reveal the low positivity of PrPSc in the cerebrospinal fluid and periodic sharp wave complexes on an electroencephalogram. Most patients with V180I-gCJD have been reported to have no family history, probably due to the older age at onset, and clinical and biochemical features indicate the specific phenotype associated with the prion protein gene mutation.

Characteristics of Different Types of Prion Diseases - China's Surveillance

This report briefly described the establishment and implementation of national surveillance for human prion disease (PrD) in China. Reported cases came from Chinese surveillance network for PrD. Immunohistochemistry, Western blot, enzyme-linked immunosorbent assay (ELISA), Polymerase Chain Reaction (PCR), and real-time quaking-induced conversion (RT-QuIC) tests were used for the samples of brain, cerebrospinal fluid (CSF), and blood. Diagnosis standard for the PrDs is based on the National Commission of Health (WS/T 562-2017). The study summarized major epidemiological, clinical and laboratory features of more than 2,100 diagnosed different types of Chinese PrD cases. Sporadic Creutzfeldt-Jacob disease (sCJD) is the predominant type of PrD (88.7%). 19 different genotypes of genetic PrDs (gPrDs) were identified, accounting for about 11.3% of all PrDs, revealing ethno-relationships. No iatrogenic CJD (iCJD) and variant CJD (vCJD) was identified. The characteristics of different types of sCJD in China showed similar features as those reported globally, but gPrDs showed an obvious ethno-relationship.

V180I genetic Creutzfeldt-Jakob disease with cardiac sympathetic nerve denervation masquerading as Parkinson's disease: A case report

RATIONALE

Creutzfeldt-Jakob disease (CJD) with a point mutation of valine to isoleucine at codon 180 of the prion protein gene (V180I) is the most frequent form of genetic CJD in Japan. However, peripheral nerve involvement, especially cardiac sympathetic denervation, has not been investigated in cases with V180I genetic CJD.We herein report a genetically confirmed case of V180I genetic CJD presenting with parkinsonism and cardiac sympathetic nerve denervation.

PATIENT CONCERNS

The patient was a 79-year-old Japanese woman who presented with subacute progressive gait disturbance and cognitive impairment. Clinical diagnosis of Parkinson's disease (PD) with mild cognitive impairment was initially suspected based on parkinsonism, such as bradykinesia, rigidity and tremor, and reduced accumulation of cardiac meta-iodobenzylguanidine (MIBG) scintigraphy.

INTERVENTIONS

Based on parkinsonism and impaired cardiac MIBG findings, levodopa/decarboxylase inhibitor was administered up to 300 mg/day; however, her symptoms were not improved.

OUTCOMES

Her motor and cognitive function progressively deteriorated.

DIAGNOSIS

Although the patient had no family history of CJD, genetic CJD was diagnosed according to extensive hyperintensities in the bilateral cortices on diffusion-weighted magnetic resonance images, positive tau protein and 14-3-3 protein in the cerebrospinal fluid and a V180I mutation with methionine homozygosity at codon 129 by prion protein gene analysis.

LESSONS

We should be aware that reduced uptake of cardiac MIBG scintigraphy in patients presenting with parkinsonism cannot confirm a diagnosis of PD. CJD should be considered when patients show a rapid progressive clinical course with atypical manifestations of PD.

Characterization of mutations in PRNP (prion) gene and their possible roles in neurodegenerative diseases

Abnormal prion proteins are responsible for several fatal neurodegenerative diseases in humans and in animals, including Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker disease, and fatal familial insomnia. Genetics is important in prion diseases, but in the most cases, cause of diseases remained unknown. Several mutations were found to be causative for prion disorders, and the effect of mutations may be heterogeneous. In addition, different prion mutations were suggested to play a possible role in additional phenotypes, such as Alzheimer's type pathology, spongiform encephalopathy, or frontotemporal dementia. Pathogenic nature of several prion mutations remained unclear, such as M129V and E219K. These two polymorphic sites were suggested as either risk factors for different disorders, such as Alzheimer's disease (AD), variant CJD, or protease-sensitive prionopathy, and they can also be disease-modifying factors. Pathological overlap may also be possible with AD or progressive dementia, and several patients with prion mutations were initially diagnosed with AD. This review also introduces briefly the diagnosis of prion diseases and the issues with their diagnosis. Since prion diseases have quite heterogeneous phenotypes, a complex analysis, a combination of genetic screening, cerebrospinal fluid biomarker analysis and imaging technologies could improve the early disease diagnosis.

Rare E196A mutation in PRNP gene of 3 Chinese patients with Creutzfeldt-Jacob disease

Inherited prion diseases are characterized by mutations in the PRNP gene, which account for 5-15% of human prion diseases. Here we reported 3 Chinese genetic Creutzfeldt-Jacob disease cases (gCJD) with a rare mutation in PRNP leading to an exchange of amino acid from glutamic acid (E) to alanine (A) at codon 196 (E196A). All three patients were Han Chinese without any sibship among them. They showed various unspecific symptoms at onset and displayed typical clinical manifestations of sporadic CJD with progress of disease. The same time, 2 cases showed psychotic symptoms during the clinical courses. 14-3-3 proteins were positive in cerebrospinal fluid (CSF) and special abnormality were detected in MRI of all the cases. The polymorphism of codon 129 was methionin homozygote and that of codon 219 was glutamate homozygote in all 3 patients. The disease durations of the 3 cases varied from 10 to 22 months and no disease associated family history was figured out in all the cases.