Evaluation of the impact of CSF prion RT-QuIC and amended criteria on the clinical diagnosis of Creutzfeldt-Jakob disease: a 10-year study in Italy.

BACKGROUND: The introduction of the prion Real-Time Quaking-Induced Conversion assay (RT-QuIC) has led to a revision of the diagnostic criteria for sporadic Creutzfeldt-Jakob disease (sCJD).Validation studies are needed for the amended criteria, especially for their diagnostic value in the clinical setting. METHODS: We studied 1250 patients with suspected CJD referred for diagnosis to two Italian reference centres between 2010 and 2020. Focusing on the first diagnostic assessment, we compared the diagnostic value of the old and the amended criteria and that of different combinations of clinical variables and biomarker results. RESULTS: The studied cohort comprised 850 participants with CJD (297 definite sCJD, 151 genetic CJD, 402 probable sCJD) and 400 with non-CJD (61 with neuropathology). At first clinical evaluation, the sensitivity of the old criteria (76.8%) was significantly lower than that of the amended criteria (97.8%) in the definite CJD cohort with no difference between definite and probable sCJD cases. Specificity was ~94% for both criteria against the non-CJD cohort (82.0% against definite non-CJD group). Cerebrospinal fluid (CSF) RT-QuIC was highly sensitive (93.9%) and fully specific against definite non-CJD patients. Limiting the criteria to a positive RT-QuIC or/and the combination of a clinical course compatible with possible CJD with a positive MRI (Q-CM criteria) provided higher diagnostic accuracy than both the old and amended criteria, overcoming the suboptimal specificity of ancillary test results (ie, CSF protein 14-3-3). CONCLUSIONS: CSF RT-QuIC is highly sensitive and specific for diagnosing CJD in vitam. The Q-CM criteria provide a high diagnostic value for CJD.

Biochemical and Neuropathological Findings in a Creutzfeldt-Jakob Disease Patient with the Rare Val180Ile-129Val Haplotype in the Prion Protein Gene.

Genetic Creutzfeldt-Jakob disease (gCJD) associated with the V180I mutation in the prion protein (PrP) gene (PRNP) in phase with residue 129M is the most frequent cause of gCJD in East Asia, whereas it is quite uncommon in Caucasians. We report on a gCJD patient with the rare V180I-129V haplotype, showing an unusually long duration of the disease and a characteristic pathological PrP (PrPSc) glycotype. Family members carrying the mutation were fully asymptomatic, as commonly observed with this mutation. Neuropathological examination showed a lesion pattern corresponding to that commonly reported in Japanese V180I cases with vacuolization and gliosis of the cerebral cortexes, olfactory areas, hippocampus and amygdala. PrP was deposited with a punctate, synaptic-like pattern in the cerebral cortex, amygdala and olfactory tract. Western blot analyses of proteinase-K-resistant PrP showed the characteristic two-banding pattern of V180I gCJD, composed of mono- and un-glycosylated isoforms. In line with reports on other V180I cases in the literature, Real-Time Quaking Induced Conversion (RT-QuIC) analyses did not demonstrate the presence of seeding activity in the cerebrospinal fluid and olfactory mucosa, suggesting that this haplotype also may result in a reduced seeding efficiency of the pathological PrP. Further studies are required to understand the origin, penetrance, disease phenotype and transmissibility of 180I-129V haplotype in Caucasians.

Spatial Epidemiology of Sporadic Creutzfeldt-Jakob Disease in Apulia, Italy.

BACKGROUND: Sporadic Creutzfeldt-Jakob disease (CJD) is a rare neurodegenerative disease caused by prions that is randomly distributed in all countries, with an overall yearly mortality rate of about 1-2 cases per million people. On a few occasions, however, sporadic CJD occurred with higher than expected rates, but further investigations failed to recognize any convincing causal link. In Italy, cluster analyses of sporadic CJD cases have not been performed previously. OBJECTIVE: To investigate the geographical distribution of sporadic CJD using municipality geographical data of Apulia with the aim of detecting spatial clusters of disease. PATIENTS AND METHODS: Patients included in this study were diagnosed as probable or definite sporadic CJD and were residents of the Apulia Region (Italy). Bayesian hierarchical models with spatially structured and unstructured random components were used to describe the spatial pattern of the disease and to assess the extent of heterogeneity among municipalities. The Kulldorff-Nagarwalla scan test and the flexible spatial scan statistic were used for detecting spatial clusters. RESULTS: Smoothed Bayesian relative risks above the null value were observed in a few adjacent municipalities in the north and middle areas of Apulia. However, both the circular scanning method and the flexible spatial scan statistic identified only a single cluster in the central part of the region. CONCLUSION: Geographical analyses and tests for spatial randomness identified a restricted area with an unusually high number of sporadic CJD cases in the Apulia region of Italy. Environmental and genetic risk factors other than mutations in the prion protein gene however, need to be investigated.

MRI abnormalities in Creutzfeldt-Jakob disease and other rapidly progressive dementia.

OBJECTIVE: To investigate brain MRI abnormalities in a cohort of patients with rapidly progressive dementia (RPD) with and without a diagnosis of Creutzfeldt-Jakob disease (CJD). METHODS: One hundred and seven patients with diagnosis of prion disease (60 with definite sCJD, 33 with probable sCJD and 14 with genetic prion disease) and 40 non-prion related RPD patients (npRPD) underwent brain MRI including DWI and FLAIR. MRIs were evaluated with a semiquantitative rating score, which separately considered abnormal signal extent and intensity in 22 brain regions. Clinical findings at onset, disease duration, cerebrospinal-fluid 14-3-3 and t-tau protein levels, and EEG data were recorded. RESULTS: Among patients with definite/probable diagnosis of CJD or genetic prion disease, 2/107 had normal DWI-MRI: in one patient a 2-months follow-up DWI-MRI showed CJD-related changes while the other had autopsy-proven CJD despite no DWI abnormalities 282 days after clinical onset. CJD-related cortical changes were detected in all lobes and involvement of thalamus was common. In the npRPD groups, 6/40 patients showed DWI alterations that clustered in three different patterns: (1) minimal/doubtful signal alterations (limbic encephalitis, dementia with Lewy bodies); (2) clearly suggestive of alternative diagnoses (status epilepticus, Wernicke or metabolic encephalopathy); (3) highly suggestive of CJD (mitochondrial disease), though cortical swelling let exclude CJD. CONCLUSIONS: In the diagnostic work-up of RPD, negative/doubtful DWI makes CJD diagnosis rather unlikely, while specific DWI patterns help differentiating CJD from alternative diagnoses. The pulvinar sign is not exclusive of the variant form.

Guillain-Barré syndrome in patients dying with COVID-19 in Italy: a retrospective study.

INTRODUCTION: We presented a four-case series of COVID-19 related deaths occurred in patients with Guillain-Barré syndrome (GBS) between February 2020 and January 2022 in Italy. METHODS: They were extracted from 8,436 medical charts of COVID-19 patients dying. All cases, ranged 48-73 years, showed classical GBS clinical onset - limb weakness, sensory deficits, hypoareflexia - and three of them were admitted in intensive care unit (ICU) for ventilator support. RESULTS: The cerebrospinal fluid showing albumin-cytological dissociation was performed in two cases. Nerve conduction studies supported the diagnosis in all cases. Interstitial pneumonia was documented by chest X-rays or CT scans in all cases: they were treated with intravenous immunoglobulin (IVIg) and the drugs used for COVID-19 infection. CONCLUSIONS: Although the mechanism of GBS onset is still unclear in COVID-19, fatal cases may be more frequent than other virus-related GBS, so that strictly monitoring in high-risk patients could dramatically decrease the mortality of GBS.

Validation of Revised International Creutzfeldt-Jakob Disease Surveillance Network Diagnostic Criteria for Sporadic Creutzfeldt-Jakob Disease.

Importance: Sporadic Creutzfeldt-Jakob disease (sCJD) is a rapidly lethal disease. Rapid, accurate diagnosis is imperative for epidemiological surveillance and public health activities to exclude treatable differentials and facilitate supportive care. In 2017, the International CJD Surveillance Network diagnostic criteria were revised to incorporate cortical ribboning on magnetic resonance imaging and the real-time quaking-induced conversion (RT-QuIC) assay, developments that require multicenter evaluation. Objective: To evaluate the accuracy of revised diagnostic criteria through the retrospective diagnosis of autopsy-confirmed cases (referred to as in-life diagnosis). Design, Setting, and Participants: This diagnostic study used a 3-year clinicopathological series using all cases of autopsy-confirmed sCJD and a noncase group with alternative neuropathological diagnoses from national surveillance centers in the United Kingdom, France, Germany, and Italy. Data were collected from January 2017 to December 2019 and analyzed from January 2020 to November 2021. Main Outcomes and Measures: Sensitivity and specificity of revised diagnostic criteria and diagnostic investigations. Secondary analyses assessing sCJD subgroups by genotype, pathological classification, disease duration, and age. Results: A total of 501 sCJD cases and 146 noncases were included. Noncase diagnoses included neurodegenerative diseases, autoimmune encephalitis, and cerebral insults such as anoxia. Participants in the sCJD cases cohort were younger (mean [SD] age, 68.8 [9.8] years vs 72.8 [10.9] years; P < .001) and had longer median (IQR) disease duration (118 [74.8-222.3] days vs 85 [51.5-205.5] days; P = .002); sex ratios were equivalent (253 [50.5%] male cases vs 74 [50.7%] male noncases). Sensitivity of revised criteria in in-life diagnosis (450 of 488 [92.2%] diagnoses; 95% CI, 89.5%-94.4%) was increased compared with prior criteria (378 of 488 [77.5%] diagnoses; 95% CI, 73.5%-81.1%; P < .001), while specificity (101 of 125 [80.8%] diagnoses; 95% CI, 72.8%-87.3%) was unchanged (102 of 125 [81.6%] diagnoses; 95% CI, 73.7%-88.0%; P > .99). Among 223 cases and 52 noncases with the full panel of investigations performed, sensitivity of revised criteria (97.8%; 95% CI, 94.9%-99.3%) was increased compared with prior criteria (76.2%; 95% CI, 70.1%-81.7%; P < .001) while specificity was unchanged (67.3%; 95% CI, 52.9%-79.7% vs 69.2%; 95% CI, 54.9%-81.3%; P > .99). In 455 cases and 111 noncases, cortical ribboning was 67.9% sensitive (95% CI, 63.4%-72.2%) and 86.5% specific (95% CI, 78.7%-92.2%). In 274 cases and 77 noncases, RT-QuIC was 91.6% sensitive (95% CI, 87.7%-94.6%) and 100% specific (95% CI, 96.2%-100%). Investigation sensitivity varied with genetic and pathological features, disease duration, and age. Conclusions and Relevance: This diagnostic study demonstrated significantly improved sensitivity of revised sCJD diagnostic criteria with unaltered specificity. The revision has enhanced diagnostic accuracy for clinical care and surveillance.

Sporadic Creutzfeldt-Jakob disease VM1: phenotypic and molecular characterization of a novel subtype of human prion disease.

The methionine (M)-valine (V) polymorphic codon 129 of the prion protein gene (PRNP) plays a central role in both susceptibility and phenotypic expression of sporadic Creutzfeldt-Jakob diseases (sCJD). Experimental transmissions of sCJD in humanized transgenic mice led to the isolation of five prion strains, named M1, M2C, M2T, V2, and V1, based on two major conformations of the pathological prion protein (PrPSc, type 1 and type 2), and the codon 129 genotype determining susceptibility and propagation efficiency. While the most frequent sCJD strains have been described in codon 129 homozygosis (MM1, MM2C, VV2) and heterozygosis (MV1, MV2K, and MV2C), the V1 strain has only been found in patients carrying VV. We identified six sCJD cases, 4 in Catalonia and 2 in Italy, carrying MV at PRNP codon 129 in combination with PrPSc type 1 and a new clinical and neuropathological profile reminiscent of the VV1 sCJD subtype rather than typical MM1/MV1. All patients had a relatively long duration (mean of 20.5 vs. 3.5 months of MM1/MV1 patients) and lacked electroencephalographic periodic sharp-wave complexes at diagnosis. Distinctive histopathological features included the spongiform change with vacuoles of larger size than those seen in sCJD MM1/MV1, the lesion profile with prominent cortical and striatal involvement, and the pattern of PrPSc deposition characterized by a dissociation between florid spongiform change and mild synaptic deposits associated with coarse, patch-like deposits in the cerebellar molecular layer. Western blot analysis of brain homogenates revealed a PrPSc type 1 profile with physicochemical properties reminiscent of the type 1 protein linked to the VV1 sCJD subtype. In summary, we have identified a new subtype of sCJD with distinctive clinicopathological features significantly overlapping with those of the VV1 subtype, possibly representing the missing evidence of V1 sCJD strain propagation in the 129MV host genotype.

Prevalence and clinical correlates of dementia among COVID-19-related deaths in Italy.

INTRODUCTION: We aimed at exploring the proportion of patients dying with COVID-19 and concomitant dementia in Italy, as well as their clinical characteristics and trajectories of care. METHODS: The proportion of COVID-19-related deaths occurring in people with dementia and the clinical characteristics of deceased individuals according to their dementia status were explored by considering the medical charts of a representative sample of patients deceased in Italian hospitals (n = 2621). RESULTS: A total of 415 individuals with dementia were identified in the study population, accounting for 15.8% of overall COVID-19-related deaths. Patients with dementia less frequently presented with cough, had lower chance of receiving supportive therapies and intensive care approaches, and showed a faster clinical worsening as compared with individuals with intact cognition. DISCUSSION: Dementia confers a relevant risk of adverse outcomes in case of SARS-CoV-2 infection and influences the clinical presentation, course and management of affected individuals.

Clinical Characteristics of Hospitalized Individuals Dying With COVID-19 by Age Group in Italy.

BACKGROUND: Aim of the present study is to describe characteristics of COVID-19-related deaths and to compare the clinical phenotype and course of COVID-19-related deaths occurring in adults (<65 years) and older adults (≥65 years). METHOD: Medical charts of 3,032 patients dying with COVID-19 in Italy (368 aged < 65 years and 2,664 aged ≥65 years) were revised to extract information on demographics, preexisting comorbidities, and in-hospital complications leading to death. RESULTS: Older adults (≥65 years) presented with a higher number of comorbidities compared to those aged <65 years (3.3 ± 1.9 vs 2.5 ± 1.8, p < .001). Prevalence of ischemic heart disease, atrial fibrillation, heart failure, stroke, hypertension, dementia, COPD, and chronic renal failure was higher in older patients (≥65 years), while obesity, chronic liver disease, and HIV infection were more common in younger adults (<65 years); 10.9% of younger patients (<65 years) had no comorbidities, compared to 3.2% of older patients (≥65 years). The younger adults had a higher rate of non-respiratory complications than older patients, including acute renal failure (30.0% vs 20.6%), acute cardiac injury (13.5% vs 10.3%), and superinfections (30.9% vs 9.8%). CONCLUSIONS: Individuals dying with COVID-19 present with high levels of comorbidities, irrespective of age group, but a small proportion of deaths occur in healthy adults with no preexisting conditions. Non-respiratory complications are common, suggesting that the treatment of respiratory conditions needs to be combined with strategies to prevent and mitigate the effects of non-respiratory complications.

Diagnosis of Human Prion Disease Using Real-Time Quaking-Induced Conversion Testing of Olfactory Mucosa and Cerebrospinal Fluid Samples.

Importance: Early and accurate in vivo diagnosis of Creutzfeldt-Jakob disease (CJD) is necessary for quickly distinguishing treatable from untreatable rapidly progressive dementias and for future therapeutic trials. This early diagnosis is becoming possible using the real-time quaking-induced conversion (RT-QuIC) seeding assay, which detects minute amounts of the disease-specific pathologic prion protein in cerebrospinal fluid (CSF) or olfactory mucosa (OM) samples. Objective: To develop an algorithm for accurate and early diagnosis of CJD by using the RT-QuIC assay on CSF samples, OM samples, or both. Design, Setting, and Participants: In this case-control study, samples of CSF and OM were collected from 86 patients with a clinical diagnosis of probable (n = 51), possible (n = 24), or suspected (n = 11) CJD and 104 negative control samples (54 CSF and 50 OM). The CSF and OM samples were analyzed using conventional RT-QuIC. The CSF samples underwent further testing using improved RT-QuIC conditions. In addition, the diagnostic performance of a novel, easy-to-use, gentle flocked swab for sampling of OM was evaluated. Data were collected from January 1 to June 30, 2015. Main Outcome and Measures: Correlations between RT-QuIC results and the final diagnosis of recruited patients. Results: Among the 86 patients (37 men [43%] and 49 women [57%]; mean [SD] age, 65.7 [11.5] years) included for analysis, all 61 patients with sporadic CJD had positive RT-QuIC findings using OM or CSF samples or both for an overall RT-QuIC diagnostic sensitivity of 100% (95% CI, 93%-100%). All patients with a final diagnosis of non-prion disease (71 CSF and 67 OM samples) had negative RT-QuIC findings for 100% specificity (95% CI, 94%-100%). Of 8 symptomatic patients with various mutations causing CJD or Gerstmann-Sträussler-Scheinker syndrome, 6 had positive and 2 had negative RT-QuIC findings for a sensitivity of 75% (95% CI, 36%-96%). Conclusions and Relevance: A proposed diagnostic algorithm for sporadic CJD combines CSF and OM RT-QuIC testing to provide virtually 100% diagnostic sensitivity and specificity in the clinical phase of the disease.

Chemokine levels in the jugular venous blood of migraine without aura patients during attacks.

OBJECTIVE: To investigate changes in the levels of calcitonin gene-related peptide and its intracellular messenger cyclic adenosine monophosphate in serial samples of internal jugular blood taken from migraine patients without aura assessed during attacks, and to assess their relationship with the levels of IL-8, MCP-1, and RANTES in the same samples. BACKGROUND: Calcitonin gene-related peptide, the marker of trigeminovascular activation, is released in both the internal and external jugular venous blood of migraine patients during attacks. Experimental evidence demonstrated that when released from C-type sensory neurons in inflammatory pain models, it differentially induced expression of neutrophil chemotactic chemokine IL-8, but not monocyte chemotactic chemokine MCP-1 or lymphocyte chemotactic chemokine RANTES. These chemokines were never investigated in migraine. DESIGN/METHODS: Eight migraine without aura patients were admitted to the hospital during the attacks. Internal jugular venous blood samples were taken immediately after catheter insertion, at the 1st, 2nd, and 4th hours after attack onset, and within 2 hours from its cessation. The levels of the sensory neuropeptide calcitonin gene-related peptide and the messenger cyclic adenosine monophosphate were measured by RIA method, and those of IL-8, MCP-1, and RANTES were measured by ELISA method. RESULTS: Higher calcitonin gene-related peptide levels were found in the internal jugular venous blood of migraine without aura patients compared with the time of catheter insertion (ANOVA: P<.0001) with a peak at the first hour (52.6+/-9.2 ng/mL). A transient increase in IL-8 was observed at the 2nd and 4th hours (P<.01 and P<.002, respectively), whereas no changes in the levels of MCP-1 and RANTES were found at any time of the study. The increase in IL-8 was accompanied by a parallel increase in cyclic adenosine monophosphate. CONCLUSIONS: The present study confirms previous findings of an increase in calcitonin gene-related peptide in internal jugular venous blood of migraine without aura patients during attacks. The transient increase in the levels of IL-8 concurs with the results of recent experimental research showing a calcitonin gene-related peptide-induced activation of IL-8 gene expression, but not RANTES and MCP-1, via the transcriptional factor AP-2, which mediates transduction in response to cyclic adenosine monophosphate. Although IL-8 is transiently increased during migraine attacks, an accumulation of leukocytes secondary to neurogenic inflammation is unlikely, as it is for other inflammatory events, because they are self limiting. Other events, including nitric oxide production, may contribute to counteract meningeal transvascular leukocyte migration during migraine attacks, as suggested by the model of sterile inflammation.