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1.
Alzheimers Dement ; 20(6): 3906-3917, 2024 06.
Article in English | MEDLINE | ID: mdl-38644660

ABSTRACT

BACKGROUND: Cortical microinfarcts (CMI) were attributed to cerebrovascular disease and cerebral amyloid angiopathy (CAA). CAA is frequent in Down syndrome (DS) while hypertension is rare, yet no studies have assessed CMI in DS. METHODS: We included 195 adults with DS, 63 with symptomatic sporadic Alzheimer's disease (AD), and 106 controls with 3T magnetic resonance imaging. We assessed CMI prevalence in each group and CMI association with age, AD clinical continuum, vascular risk factors, vascular neuroimaging findings, amyloid/tau/neurodegeneration biomarkers, and cognition in DS. RESULTS: CMI prevalence was 11.8% in DS, 4.7% in controls, and 17.5% in sporadic AD. In DS, CMI increased in prevalence with age and the AD clinical continuum, was clustered in the parietal lobes, and was associated with lacunes and cortico-subcortical infarcts, but not hemorrhagic lesions. DISCUSSION: In DS, CMI are posteriorly distributed and related to ischemic but not hemorrhagic findings suggesting they might be associated with a specific ischemic CAA phenotype. HIGHLIGHTS: This is the first study to assess cortical microinfarcts (assessed with 3T magnetic resonance imaging) in adults with Down syndrome (DS). We studied the prevalence of cortical microinfarcts in DS and its relationship with age, the Alzheimer's disease (AD) clinical continuum, vascular risk factors, vascular neuroimaging findings, amyloid/tau/neurodegeneration biomarkers, and cognition. The prevalence of cortical microinfarcts was 11.8% in DS and increased with age and along the AD clinical continuum. Cortical microinfarcts were clustered in the parietal lobes, and were associated with lacunes and cortico-subcortical infarcts, but not hemorrhagic lesions. In DS, cortical microinfarcts are posteriorly distributed and related to ischemic but not hemorrhagic findings suggesting they might be associated with a specific ischemic phenotype of cerebral amyloid angiopathy.


Subject(s)
Alzheimer Disease , Down Syndrome , Magnetic Resonance Imaging , Humans , Down Syndrome/pathology , Down Syndrome/complications , Down Syndrome/diagnostic imaging , Female , Male , Middle Aged , Alzheimer Disease/pathology , Alzheimer Disease/diagnostic imaging , Adult , Aged , Cerebral Infarction/diagnostic imaging , Cerebral Infarction/pathology , Prevalence , Cerebral Amyloid Angiopathy/diagnostic imaging , Cerebral Amyloid Angiopathy/pathology , Cerebral Amyloid Angiopathy/complications , Risk Factors , Cerebral Cortex/pathology , Cerebral Cortex/diagnostic imaging
2.
Alzheimers Dement ; 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39087352

ABSTRACT

INTRODUCTION: In Down syndrome (DS), white matter hyperintensities (WMHs) are highly prevalent, yet their topography and association with sociodemographic data and Alzheimer's disease (AD) biomarkers remain largely unexplored. METHODS: In 261 DS adults and 131 euploid controls, fluid-attenuated inversion recovery magnetic resonance imaging scans were segmented and WMHs were extracted in concentric white matter layers and lobar regions. We tested associations with AD clinical stages, sociodemographic data, cerebrospinal fluid (CSF) AD biomarkers, and gray matter (GM) volume. RESULTS: In DS, total WMHs arose at age 43 and showed stronger associations with age than in controls. WMH volume increased along the AD continuum, particularly in periventricular regions, and frontal, parietal, and occipital lobes. Associations were found with CSF biomarkers and temporo-parietal GM volumes. DISCUSSION: WMHs increase 10 years before AD symptom onset in DS and are closely linked with AD biomarkers and neurodegeneration. This suggests a direct connection to AD pathophysiology, independent of vascular risks. HIGHLIGHTS: White matter hyperintensities (WMHs) increased 10 years before Alzheimer's disease symptom onset in Down syndrome (DS). WMHs were strongly associated in DS with the neurofilament light chain biomarker. WMHs were more associated in DS with gray matter volume in parieto-temporal areas.

3.
Alzheimers Dement ; 2024 Aug 03.
Article in English | MEDLINE | ID: mdl-39096164

ABSTRACT

INTRODUCTION: We developed a multimarker blood test result interpretation tool for the clinical dementia practice, including phosphorylated (P-)tau181, amyloid-beta (Abeta)42/40, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL). METHODS: We measured the plasma biomarkers with Simoa (n = 1199), applied LASSO regression for biomarker selection and receiver operating characteristics (ROC) analyses to determine diagnostic accuracy. We validated our findings in two independent cohorts and constructed a visualization approach. RESULTS: P-tau181, GFAP, and NfL were selected. This combination had area under the curve (AUC) = 83% to identify amyloid positivity in pre-dementia stages, AUC = 87%-89% to differentiate Alzheimer's or controls from frontotemporal dementia, AUC = 74%-76% to differentiate Alzheimer's or controls from dementia with Lewy bodies. Highly reproducible AUCs were obtained in independent cohorts. The resulting visualization tool includes UpSet plots to visualize the stand-alone biomarker results and density plots to visualize the biomarker results combined. DISCUSSION: Our multimarker blood test interpretation tool is ready for testing in real-world clinical dementia settings. HIGHLIGHTS: We developed a multimarker blood test interpretation tool for clinical dementia practice. Our interpretation tool includes plasma biomarkers P-tau, GFAP, and NfL. Our tool is particularly useful for Alzheimer's and frontotemporal dementia diagnosis.

4.
Clin Chem Lab Med ; 61(9): 1580-1589, 2023 08 28.
Article in English | MEDLINE | ID: mdl-37083158

ABSTRACT

OBJECTIVES: Alzheimer's disease (AD) is considered the most common cause of dementia in older people. Recently, blood-based markers (BBM) Aß1-42, Aß1-40, and phospho Tau181 (p-Tau181) have demonstrated the potential to transform the diagnosis and prognostic assessment of AD. Our aim was to investigate the effect of different storage conditions on the quantification of these BBM and to evaluate the interchangeability of plasma and serum samples. METHODS: Forty-two individuals with some degree of cognitive impairment were studied. Thirty further patients were retrospectively selected. Aß1-42, Aß1-40, and p-Tau181 were quantified using the LUMIPULSE-G600II automated platform. To assess interchangeability between conditions, correction factors for magnitudes that showed strong correlations were calculated, followed by classification consistency studies. RESULTS: Storing samples at 4 °C for 8-9 days was associated with a decrease in Aß fractions but not when stored for 1-2 days. Using the ratio partially attenuated the pre-analytical effects. For p-Tau181, samples stored at 4 °C presented lower concentrations, whereas frozen samples presented higher ones. Concerning classification consistency in comparisons that revealed strong correlations (p-Tau181), the percentage of total agreement was greater than 90 % in a large number of the tested cut-offs values. CONCLUSIONS: Our findings provide relevant information for the standardization of sample collection and storage in the analysis of AD BBM in an automated platform. This knowledge is crucial to ensure their introduction into clinical settings.


Subject(s)
Alzheimer Disease , Humans , Aged , Alzheimer Disease/diagnosis , tau Proteins , Amyloid beta-Peptides , Retrospective Studies , Biomarkers
5.
Alzheimers Dement ; 19(9): 3916-3925, 2023 09.
Article in English | MEDLINE | ID: mdl-37038748

ABSTRACT

BACKGROUND: Down syndrome (DS) is a genetic form of Alzheimer's disease (AD). However, clinical diagnosis is difficult, and experts emphasize the need for detecting intra-individual cognitive decline. OBJECTIVE: To compare the performance of baseline and longitudinal neuropsychological assessments for the diagnosis of symptomatic AD in DS. METHODS: Longitudinal cohort study of adults with DS. Individuals were classified as asymptomatic, prodromal AD, or AD dementia. We performed receiver operating characteristic curve analyses to compare baseline and longitudinal changes of CAMCOG-DS and mCRT. RESULTS: We included 562 adults with DS. Baseline assessments showed good to excellent diagnostic performance for AD dementia (AUCs between 0.82 and 0.99) and prodromal AD, higher than the 1-year intra-individual cognitive decline (area under the ROC curve between 0.59 and 0.79 for AD dementia, lower for prodromal AD). Longer follow-ups increased the diagnostic performance of the intra-individual cognitive decline. DISCUSSION: Baseline cognitive assessment outperforms the 1-year intra-individual cognitive decline in adults with DS.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Down Syndrome , Adult , Humans , Alzheimer Disease/diagnosis , Alzheimer Disease/psychology , Down Syndrome/complications , Down Syndrome/diagnosis , Down Syndrome/genetics , Longitudinal Studies , Cross-Sectional Studies , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/psychology , Neuropsychological Tests , Cognition
6.
Alzheimers Dement ; 19(11): 4817-4827, 2023 11.
Article in English | MEDLINE | ID: mdl-37021589

ABSTRACT

BACKGROUND: Basal forebrain (BF) degeneration occurs in Down syndrome (DS)-associated Alzheimer's disease (AD). However, the dynamics of BF atrophy with age and disease progression, its impact on cognition, and its relationship with AD biomarkers have not been studied in DS. METHODS: We included 234 adults with DS (150 asymptomatic, 38 prodromal AD, and 46 AD dementia) and 147 euploid controls. BF volumes were extracted from T-weighted magnetic resonance images using a stereotactic atlas in SPM12. We assessed BF volume changes with age and along the clinical AD continuum and their relationship to cognitive performance, cerebrospinal fluid (CSF) and plasma amyloid/tau/neurodegeneration biomarkers, and hippocampal volume. RESULTS: In DS, BF volumes decreased with age and along the clinical AD continuum and significantly correlated with amyloid, tau, and neurofilament light chain changes in CSF and plasma, hippocampal volume, and cognitive performance. DISCUSSION: BF atrophy is a potentially valuable neuroimaging biomarker of AD-related cholinergic neurodegeneration in DS.


Subject(s)
Alzheimer Disease , Basal Forebrain , Down Syndrome , Humans , Adult , Alzheimer Disease/pathology , Down Syndrome/diagnostic imaging , Down Syndrome/complications , Atrophy/pathology , Biomarkers/cerebrospinal fluid
7.
Clin Chem Lab Med ; 60(7): 1058-1063, 2022 06 27.
Article in English | MEDLINE | ID: mdl-35405043

ABSTRACT

OBJECTIVES: Alzheimer's disease (AD) is considered the most common cause of dementia in older people. Cerebrospinal fluid (CSF) Aß1-42, Aß1-40, total Tau (t-Tau), and phospho Tau (p-Tau) are important biomarkers for the diagnosis, however, they are highly dependent on the pre-analytical conditions. Our aim was to investigate the potential influence of different storage conditions on the simultaneous quantification of these biomarkers in a fully-automated platform to accommodate easier pre-analytical conditions for laboratories. METHODS: CSF samples were obtained from 11 consecutive patients. Aß1-42, Aß1-40, p-Tau, and t-Tau were quantified using the LUMIPULSE G600II automated platform. RESULTS: Temperature and storage days significantly influenced Aß1-42 and Aß1-40 with concentrations decreasing with days spent at 4 °C. The use of the Aß1-42/Aß1-40 ratio could partly compensate it. P-Tau and t-Tau were not affected by any of the tested storage conditions. For conditions involving storage at 4 °C, a correction factor of 1.081 can be applied. Diagnostic agreement was almost perfect in all conditions. CONCLUSIONS: Cutoffs calculated in samples stored at -80 °C can be safely used in samples stored at -20 °C for 15-16 days or up to two days at RT and subsequent freezing at -80 °C. For samples stored at 4 °C, cutoffs would require applying a correction factor, allowing to work with the certainty of reaching the same clinical diagnosis.


Subject(s)
Alzheimer Disease , Aged , Alzheimer Disease/cerebrospinal fluid , Alzheimer Disease/diagnosis , Amyloid beta-Peptides/cerebrospinal fluid , Biomarkers/cerebrospinal fluid , Humans , Peptide Fragments/cerebrospinal fluid , tau Proteins/cerebrospinal fluid
8.
Analyst ; 145(24): 7916-7921, 2021 Jan 07.
Article in English | MEDLINE | ID: mdl-33020772

ABSTRACT

Urinary tract infections (UTI) have a high prevalence and can yield poor patient outcomes if they progress to urosepsis. Here we introduce mobile origami biosensors that detect UTIs caused by E. coli at the bedside in less than 7 minutes. The origami biosensors are made of a single piece of paper that contains antibody-decorated nanoparticles. When the urine sample contains E. coli, the biosensors generate colored spots on the paper strip. These are then quantified with a mobile app that calculates the pixel intensity in real time. The tests are highly specific and do not cross-react with other common uropathogens. Furthermore, the biosensors only yielded one false negative result when queried with a panel containing 57 urine samples from patients, which demonstrates that they have excellent sensitivity and specificity. This, along with the rapid assay time and smartphone-based detection, makes them useful for aiding in the diagnosis of UTIs at the point of care.


Subject(s)
Biosensing Techniques , Escherichia coli Infections , Urinary Tract Infections , Escherichia coli , Escherichia coli Infections/diagnosis , Humans , Immunoassay , Urinary Tract Infections/diagnosis
9.
J Minim Invasive Gynecol ; 25(7): 1142-1143, 2018.
Article in English | MEDLINE | ID: mdl-29427781

ABSTRACT

STUDY OBJECTIVE: To review/learn a surgical technique not very well-known by gynecologic oncologists. DESIGN: Level of evidence III. SETTING: A review of a surgical technique with emphasis on the para-aortic sentinel lymph nodes using indocyanine green. INTERVENTION: The film features the following steps to perform the procedure: 1. Creating a retroperitoneal window. 2. What to do if the peritoneum is torn. 3. Finding the psoas muscle, right ureter, and common iliac artery. Dissecting the right common iliac artery caudally to the bifurcation of the external iliac artery and internal iliac artery and cranially to the inferior mesenteric artery, the ovarian arteries, and the left renal vein. 4. A view of all of the nodes with fluorescence when indocyanine green is injected into the cervix. At present, the sentinel lymph nodes are not the standard of care for locally advanced cervical cancer. If the nodes are metastatic at this stage, all the para-aortic area will undergo radiation therapy. 5. Dissecting the inferior vena cava from the intersection with the right uterer to the right and left renal veins. 6. Performing the lateroaortic, preaortic, and precaval lymphadenectomy. 7. A final view with all of the elements (i.e., bifurcation of the common iliac artery, the left renal vein, and both ureters). 8. In the final part of the video, we open the peritoneal window to decrease the incidence of lymphoceles. CONCLUSION: The real novelty of this video is how the para-aortic area nodes are seen when green indocyanine is injected into the cervix. This video shows a simplified technique of retroperitoneal para-aortic lymphadenectomy using an advanced bipolar sealant. Some tips and tricks to facilitate the procedure are emphasized, especially in cases of accidental peritoneal tears. To decrease the incidence of lymphoceles before completing the surgery, the peritoneal window should be opened. This surgical technique is especially useful in endometrial cancer for staging the para-aortic area in obese patients and in advanced cervical cancer to determine the field of radiotherapy.


Subject(s)
Laparoscopy/methods , Lymph Node Excision/methods , Uterine Cervical Neoplasms/surgery , Aorta, Abdominal/pathology , Endometrial Neoplasms/pathology , Endometrial Neoplasms/surgery , Female , Humans , Lymph Nodes/pathology , Lymphatic Metastasis , Neoplasm Staging , Peritoneum/pathology , Retroperitoneal Space , Uterine Cervical Neoplasms/pathology
10.
Emerg Infect Dis ; 22(9): 1537-44, 2016 09.
Article in English | MEDLINE | ID: mdl-27268303

ABSTRACT

The 2013-2016 outbreak of Ebola virus disease (EVD) in West Africa infected >28,000 people, including >11,000 who died, and disrupted social life in the region. We retrospectively studied clinical signs and symptoms and risk factors for fatal outcome among 31 Ebola virus-positive patients admitted to the Ebola Treatment Center in Moyamba District, Sierra Leone. We found a higher rate of bleeding manifestations than reported elsewhere during the outbreak. Significant predictors for death were shorter time from symptom onset to admission, male sex, high viral load on initial laboratory testing, severe pain, diarrhea, bloody feces, and development of other bleeding manifestations during hospitalization. These risk factors for death could be used to identify patients in need of more intensive medical support. The lack of fever in as many as one third of EVD cases may have implications for temperature-screening practices and case definitions.


Subject(s)
Disease Outbreaks , Ebolavirus , Hemorrhagic Fever, Ebola/diagnosis , Hemorrhagic Fever, Ebola/epidemiology , Symptom Assessment , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Ebolavirus/genetics , Female , Hemorrhagic Fever, Ebola/history , Hemorrhagic Fever, Ebola/virology , History, 21st Century , Humans , Infant , Infectious Disease Incubation Period , Male , Middle Aged , Mortality , Population Surveillance , Retrospective Studies , Sierra Leone/epidemiology , Viral Load , Young Adult
11.
BMC Infect Dis ; 16: 308, 2016 06 22.
Article in English | MEDLINE | ID: mdl-27334891

ABSTRACT

BACKGROUND: The last ebola virus disease (EVD) outbreak has been the most important since 1976. EVD cases decreased drastically in Sierra Leone at the beginning of 2015. We aim to determine the clinical findings and evolution of patients admitted to an Ebola treatment center (ETC) during the epidemic's late phase. METHODS: We analyze retrospectively data of patients admitted to the Moyamba ETC (December 2014-March 2015). Patients were classified in EVD or non-EVD patients according to the results of Ebola virus real-time reverse transcription polymerase chain reaction (ZAIRE-RT-PCR). RESULTS: Seventy-five patients were included, 41.3 % were positive for ZAIRE-RT-PCR. More women (68 % vs 28 %, p = 0.001) were EVD-positive. More EVD patients had previous contact with an Ebola patient (74.2 % vs 36.3 %, p < 0.001). At admission, EVD patients were more likely to have fatigue (96.7 %, p < 0.001), diarrhea (67.7 %, p = 0.002), and muscle pain (61.3 %, p = 0.009); but only objective fevers in 35.5 % of EVD patients. The most reliable criteria for diagnosis were: contact with an Ebola patient plus three WHO symptoms (LR + =3.7, 95 % CI = 1.9-7.3), and positive contact (LR + =2.3, 95 % CI = 1.15-4.20). Only 45.2 % of EVD patients developed fevers during stay, but 75 % developed gastrointestinal symptoms. Non-EVD patients had gastrointestinal problems (33 %), respiratory conditions (26.6 %), and others such as malaria, HIV or tuberculosis with a mortality rate of 11.4 %. vs 58 % in EVD group (p < 0.001). CONCLUSIONS: More non-EVD patients were admitted in the outbreak's late phases. The low percentage of initial fever highlights the need to emphasize the epidemiological information. EVD patients presented new symptoms getting worse and requiring closer follow-up. Diagnoses of non-EVD patients were diverse with a remarkable mortality, presenting a challenge for the health system.


Subject(s)
Disease Outbreaks , Epidemics , Gastrointestinal Diseases/epidemiology , HIV Infections/epidemiology , Hemorrhagic Fever, Ebola/epidemiology , Referral and Consultation , Respiratory Tract Diseases/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Diarrhea/epidemiology , Diarrhea/etiology , Ebolavirus/genetics , Fatigue/epidemiology , Fatigue/etiology , Female , Fever/epidemiology , Fever/etiology , Gastrointestinal Diseases/complications , Gastrointestinal Diseases/diagnosis , HIV Infections/complications , HIV Infections/diagnosis , Hemorrhagic Fever, Ebola/complications , Hemorrhagic Fever, Ebola/diagnosis , Hospitalization , Humans , Infant , Infant, Newborn , Malaria/epidemiology , Male , Middle Aged , Real-Time Polymerase Chain Reaction/methods , Respiratory Tract Diseases/complications , Respiratory Tract Diseases/diagnosis , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction , Sierra Leone/epidemiology , Young Adult
12.
Aten Primaria ; 46(9): 492-500, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24768657

ABSTRACT

OBJECTIVE: To evaluate the effectiveness of two types of intervention in reducing antibiotic prescribing in respiratory tract infections (RTI). DESIGN: Before-after audit-based study. SETTING: Primary Care centres in Spain. PARTICIPANTS: General practitioners (GPs) registered all patients with RTIs for 15 days in winter 2008 (pre-intervention), and again in winter 2009 (post-intervention). INTERVENTIONS: Intervention activities included meetings, with the presentation and discussion of the results, and several training meetings on RTI guidelines, information brochures for patients, workshops on point-of-care tests - rapid antigen detection tests and C-reactive protein rapid test - and provision of these tests in the clinic. All GPs, with the exception of those in Catalonia, made up the full intervention group (FIG); conversely, Catalan doctors underwent the same intervention, except for the workshop on rapid tests (partial intervention group, PIG). Multilevel logistic regression was performed taking the prescription of antibiotics as the dependent variable. RESULTS: Out of a total of 309 GPs involved in the first register, 281 completed the intervention and the second register (90.9%), of which 210 were assigned to the FIG, and 71 to the PIG. The odds ratio of antibiotic prescribing after the intervention was 0.99 (95% CI: 0.89-1.10) among GPs assigned to PIG, and 0.50 (95% CI: 0.44-0.57, p<0.001) among those who were allocated to FIG. The reduction in antibiotic prescribing in FIG was more marked in flu infection, common cold, acute pharyngitis, acute tonsillitis, and acute bronchitis. CONCLUSIONS: Active participation of GPs with the performance of point-of-care tests in the clinic is accompanied by a drastic reduction of antibiotic use in RTIs, primarily in infections considered as mainly viral.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Drug Prescriptions/statistics & numerical data , Drug Prescriptions/standards , Respiratory Tract Infections/drug therapy , Controlled Before-After Studies , Humans , Medical Audit , Primary Health Care , Spain
13.
Alzheimers Res Ther ; 16(1): 139, 2024 06 26.
Article in English | MEDLINE | ID: mdl-38926773

ABSTRACT

BACKGROUND: Recently developed blood markers for Alzheimer's disease (AD) detection have high accuracy but usually require ultra-sensitive analytic tools not commonly available in clinical laboratories, and their performance in clinical practice is unknown. METHODS: We analyzed plasma samples from 290 consecutive participants that underwent lumbar puncture in routine clinical practice in a specialized memory clinic (66 cognitively unimpaired, 130 participants with mild cognitive impairment, and 94 with dementia). Participants were classified as amyloid positive (A +) or negative (A-) according to CSF Aß1-42/Aß1-40 ratio. Plasma pTau217, pTau181, Aß1-42 and Aß1-40 were measured in the fully-automated LUMIPULSE platform. We used linear regression to compare plasma biomarkers concentrations between A + and A- groups, evaluated Spearman's correlation between plasma and CSF and performed ROC analyses to assess their diagnostic accuracy to detect brain amyloidosis as determined by CSF Aß1-42/Aß1-40 ratio. We analyzed the concordance of pTau217 with CSF amyloidosis. RESULTS: Plasma pTau217 and pTau181 concentration were higher in A + than A- while the plasma Aß1-42/Aß1-40 ratio was lower in A + compared to A-. pTau181 and the Aß1-42/Aß1-40 ratio showed moderate correlation between plasma and CSF (Rho = 0.66 and 0.69, respectively). The areas under the ROC curve to discriminate A + from A- participants were 0.94 (95% CI 0.92-0.97) for pTau217, and 0.88 (95% CI 0.84-0.92) for both pTau181 and Aß1-42/Aß1-40. Chronic kidney disease (CKD) was related to increased plasma biomarker concentrations, but ratios were less affected. Plasma pTau217 had the highest fold change (× 3.2) and showed high predictive capability in discriminating A + from A-, having 4-7% misclassification rate. The global accuracy of plasma pTau217 using a two-threshold approach was robust in symptomatic groups, exceeding 90%. CONCLUSION: The evaluation of blood biomarkers on an automated platform exhibited high diagnostic accuracy for AD pathophysiology, and pTau217 showed excellent diagnostic accuracy to identify participants with AD in a consecutive sample representing the routine clinical practice in a specialized memory unit.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Biomarkers , Peptide Fragments , tau Proteins , Humans , Amyloid beta-Peptides/blood , Amyloid beta-Peptides/cerebrospinal fluid , Alzheimer Disease/blood , Alzheimer Disease/diagnosis , Alzheimer Disease/cerebrospinal fluid , Female , Male , Peptide Fragments/blood , Peptide Fragments/cerebrospinal fluid , tau Proteins/blood , tau Proteins/cerebrospinal fluid , Aged , Biomarkers/blood , Biomarkers/cerebrospinal fluid , Middle Aged , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/blood , Cognitive Dysfunction/cerebrospinal fluid , Aged, 80 and over , ROC Curve , Phosphorylation
14.
Neurology ; 103(4): e209676, 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39074338

ABSTRACT

BACKGROUND AND OBJECTIVES: Cerebral hemorrhages are an exclusion criterion and potential adverse effect of antiamyloid agents. It is, therefore, critical to characterize the natural history of cerebral microbleeds in populations genetically predisposed to Alzheimer disease (AD), such as Down syndrome (DS). We aimed to assess microbleed emergence in adults with DS across the AD spectrum, defining their topography and associations with clinical variables, cognitive outcomes, and fluid and neuroimaging biomarkers. METHODS: This cross-sectional study included participants aged 18 years or older from the Down-Alzheimer Barcelona Neuroimaging Initiative and Sant Pau Initiative on Neurodegeneration with T1-weighted and susceptibility-weighted images. Participants underwent comprehensive assessments, including apolipoprotein E (APOE) genotyping; fluid and plasma determinations of beta-amyloid, tau, and neurofilament light; cognitive outcomes (Cambridge Cognitive Examination and modified Cued Recall Test); and vascular risk factors (hypertension, diabetes mellitus, and dyslipidemia). We manually segmented microbleeds and characterized their topography. Associations between microbleed severity and AD biomarkers were explored using between-group comparisons (none vs 1 vs 2+) and multivariate linear models. RESULTS: We included 276 individuals with DS and 158 healthy euploid controls (mean age = 47.8 years, 50.92% female). Individuals with DS were more likely to have microbleeds than controls (20% vs 8.9%, p < 0.001), with more severe presentation (12% with 2+ vs 1.9%). Microbleeds increased with age (12% 20-30 years vs 60% > 60 years) and AD clinical stage (12.42% asymptomatic, 27.9% prodromal, 35.09% dementia) were more common in APOEε4 carriers (26% vs 18.3% noncarriers, p = 0.008), but not associated with vascular risk factors (p > 0.05). Microbleeds were predominantly posterior (cerebellum 33.66%; occipital 14.85%; temporal 21.29%) in participants with DS. Associations with microbleed severity were found for neuroimaging and fluid AD biomarkers, but only hippocampal volumes (standardized ß = -0.18 [-0.31, -0.06], p < 0.005) and CSF p-tau-181 concentrations (ß = 0.26 [0.12, 0.41], p < 0.005) survived regression controlling for age and disease stage, respectively. Microbleeds had limited effect on cognitive outcomes. DISCUSSION: In participants with DS, microbleeds present with a posterior, lobar predominance, are associated with disease severity, but do not affect cognitive performance. These results suggest an interplay between AD pathology and vascular lesions, implicating microbleeds as a risk factor limiting the use of antiamyloid agents in this population.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Biomarkers , Cerebral Hemorrhage , Down Syndrome , tau Proteins , Humans , Down Syndrome/cerebrospinal fluid , Down Syndrome/complications , Down Syndrome/diagnostic imaging , Female , Male , Middle Aged , Cross-Sectional Studies , Biomarkers/cerebrospinal fluid , Biomarkers/blood , Cerebral Hemorrhage/diagnostic imaging , Cerebral Hemorrhage/cerebrospinal fluid , Alzheimer Disease/cerebrospinal fluid , Alzheimer Disease/diagnostic imaging , Amyloid beta-Peptides/cerebrospinal fluid , tau Proteins/cerebrospinal fluid , Adult , Magnetic Resonance Imaging , Aged , Apolipoproteins E/genetics , Neurofilament Proteins/cerebrospinal fluid , Neurofilament Proteins/blood
15.
EBioMedicine ; 108: 105345, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39299003

ABSTRACT

BACKGROUND: The identification of patients with an elevated risk of developing Alzheimer's disease (AD) dementia and eligible for the disease-modifying treatments (DMTs) in the earliest stages is one of the greatest challenges in the clinical practice. Plasma biomarkers has the potential to predict these issues, but further research is still needed to translate them to clinical practice. Here we evaluated the clinical applicability of plasma pTau181 as a predictive marker of AD pathology in a large real-world cohort of a memory clinic. METHODS: Three independent cohorts (modelling [n = 991, 59.7% female], testing [n = 642, 56.2% female] and validation [n = 441, 55.1% female]) of real-world patients with subjective cognitive decline (SCD), mild cognitive impairment (MCI), AD dementia, and other dementias were included. Paired cerebrospinal fluid (CSF) and plasma samples were used to measure AT(N) CSF biomarkers and plasma pTau181. FINDINGS: CSF and plasma pTau181 showed correlation in all phenotypes except in SCD and other dementias. Age significantly influenced the biomarker's performance. The general Aß(+) vs Aß(-) ROC curve showed an AUC = 0.77 [0.74-0.80], whereas the specific ROC curve of MCI due to AD vs non-AD MCI showed an AUC = 0.89 [0.85-0.93]. A cut-off value of 1.30 pg/ml of plasma pTau181 exhibited a sensitivity of 93.57% [88.72-96.52], specificity of 72.38% [62.51-79.01], VPP of 77.85% [70.61-83.54], and 8.30% false negatives in the subjects with MCI of the testing cohort. The HR of cox regression showed that patients with MCI up to this cut-off value exhibited a HR = 1.84 [1.05-3.22] higher risk to convert to AD dementia than patients with MCI below the cut-off value. INTERPRETATION: Plasma pTau181 has the potential to be used in the memory clinics as a screening biomarker of AD pathology in subjects with MCI, presenting a valuable prognostic utility in predicting the MCI conversion to AD dementia. In the context of a real-world population, a confirmatory test employing gold-standard procedures is still advisable. FUNDING: This study has been mainly funded by Ace Alzheimer Center Barcelona, Instituto de Salud Carlos III (ISCIII), Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED), Spanish Ministry of Science and Innovation, Fundación ADEY, Fundación Echevarne and Grífols S.A.

16.
Article in English | MEDLINE | ID: mdl-38965027

ABSTRACT

The Spanish Society of Tropical Medicine and International Health (SEMTSI), the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), the Spanish Society of Emergency Medicine (SEMES), the Spanish Society of Primary Care Physicians (SEMERGEN) and the Spanish Society of Family and Community Medicine (SEMFYC) have prepared a consensus statement on the diagnosis and management of patients with imported febrile illnesses. Twenty authors with different backgrounds and representing different healthcare perspectives (ambulatory primary care, travel and tropical medicine specialists, emergency medicine, hospital care, microbiology and parasitology and public health), identified 39 relevant questions, which were organised in 7 thematic blocks. After a systematic review of the literature and a thoughtful discussion, the authors prepared 125 recommendations, as well as several tables and figures to be used as a consulting tool. The present executive summary shows a selection of some of the most relevant questions and recommendations included in the guidelines.


Subject(s)
Communicable Diseases, Imported , Fever , Humans , Fever/etiology , Fever/diagnosis , Communicable Diseases, Imported/diagnosis , Communicable Diseases, Imported/therapy , Travel-Related Illness , Spain
17.
BMC Fam Pract ; 14: 50, 2013 Apr 17.
Article in English | MEDLINE | ID: mdl-23594463

ABSTRACT

BACKGROUND: Streptococcus pneumoniae is the bacterial agent which most frequently causes pneumonia. In some Scandinavian countries, this infection is treated with penicillin V since the resistances of pneumococci to this antibiotic are low. Four reasons justify the undertaking of this study; firstly, the cut-off points which determine whether a pneumococcus is susceptible or resistant to penicillin have changed in 2008 and according to some studies published recently the pneumococcal resistances to penicillin in Spain have fallen drastically, with only 0.9% of the strains being resistant to oral penicillin (minimum inhibitory concentration>2 µg/ml); secondly, there is no correlation between pneumococcal infection by a strain resistant to penicillin and therapeutic failure in pneumonia; thirdly, the use of narrow-spectrum antibiotics is urgently needed because of the dearth of new antimicrobials and the link observed between consumption of broad-spectrum antibiotics and emergence and spread of antibacterial resistance; and fourthly, no clinical study comparing amoxicillin and penicillin V in pneumonia in adults has been published. Our aim is to determine whether high-dose penicillin V is as effective as high-dose amoxicillin for the treatment of uncomplicated community-acquired pneumonia. METHODS: We will perform a parallel group, randomised, double-blind, trial in primary healthcare centres in Spain. Patients aged 18 to 65 without significant associated comorbidity attending the physician with signs and symptoms of lower respiratory tract infection and radiological confirmation of the diagnosis of pneumonia will be randomly assigned to either penicillin V 1.6 million units thrice-daily during 10 days or amoxicillin 1,000 mg thrice-daily during 10 days. The main outcome will be clinical cure at 14 days, defined as absence of fever, resolution or improvement of cough, improvement of general wellbeing and resolution or reduction of crackles indicating that no other antimicrobial treatment will be necessary. Any clinical result other than the anterior will be considered as treatment failure. A total of 210 patients will be recruited to detect a non-inferiority margin of 15% between the two treatments with a minimum power of 80% considering an alpha error of 2.5% for a unilateral hypothesis and maximum possible losses of 15%. DISCUSSION: This pragmatic trial addresses the long-standing hypothesis that the administration of high doses of a narrow-spectrum antibiotic (penicillin V) in patients with non-severe pneumonia attended in the community is not less effective than high doses of amoxicillin (treatment currently recommended) in patients under the age of 65 years. TRIAL REGISTRATION: EudraCT number 2012-003511-63.


Subject(s)
Amoxicillin/administration & dosage , Anti-Bacterial Agents/administration & dosage , Community Health Services , Penicillin V/administration & dosage , Pneumonia, Pneumococcal/drug therapy , Research Design , Administration, Oral , Adolescent , Adult , Aged , Double-Blind Method , Humans , Middle Aged , Pneumonia, Pneumococcal/microbiology , Spain , Streptococcus pneumoniae , Young Adult
18.
Cir Esp ; 91(1): 9-16, 2013 Jan.
Article in Spanish | MEDLINE | ID: mdl-22154535

ABSTRACT

Diffusion weighted imaging (DWI) in magnetic resonance imaging (MRI) is currently an important tool for detecting and characterising hepatic lesions, as well as for monitoring and evaluating the response to the treatment of the tumour disease. The use of this technique is also being assessed for the study of diffuse liver disease. Among the additional advantages of DWI-MRI, is the absence of emission of ionising radiation and not having to use paramagnetic contrasts, which means it can be used in the study of patients with renal failure. Another advantage is the short duration of the diffusion sequence, which means that the examination time in abdominal MRI is scarcely increased. Therefore, it is important that the physician is aware of this diagnostic technique, since DWI is a sequence that should be routinely included in the liver MRI study protocol.


Subject(s)
Diffusion Magnetic Resonance Imaging , Liver Diseases/diagnosis , Humans , Physical Phenomena
19.
Res Sq ; 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38168408

ABSTRACT

BACKGROUND: Recently developed blood markers for Alzheimer's disease (AD) detection have high accuracy but usually require ultra-sensitive analytic tools not commonly available in clinical laboratories, and their performance in clinical practice is unknown. METHODS: We analyzed plasma samples from 290 consecutive participants that underwent lumbar puncture in routine clinical practice in a specialized memory clinic (66 cognitively unimpaired, 130 participants with mild cognitive impairment, and 94 with dementia). Participants were classified as amyloid positive (A+) or negative (A-) according to CSF Aß1-42/Aß1-40 ratio. Plasma pTau217, pTau181, Aß1-42 and Aß1-40 were measured in the fully-automated LUMIPULSE platform. We used linear regression to compare plasma biomarkers concentrations between A + and A- groups, evaluated Spearman's correlation between plasma and CSF and performed ROC analyses to assess their diagnostic accuracy to detect brain amyloidosis as determined by CSF Aß1-42/Aß1-40 ratio. We analyzed the potential of pTau217 to predict amyloidosis in CSF. RESULTS: Plasma pTau217 and pTau181 concentration were higher in A + than A- while the plasma Aß1-42/Aß1-40 ratio was lower in A + compared to A-. pTau181 and the Aß1-42/Aß1-40 ratio showed moderate correlation between plasma and CSF (Rho = 0.66 and 0.69, respectively). The areas under the ROC curve to discriminate A + from A- participants were 0.94 (95% CI 0.92-0.97) for pTau217, and 0.88 (95% CI 0.84-0.92) for both pTau181 and Aß1-42/Aß1-40. Chronic kidney disease (CKD) was related to increased plasma biomarker concentrations, but ratios were less affected. Plasma pTau217 had the highest fold change (x4.2) and showed high predictive capability in discriminating A + from A-, having 4-7% misclassification rate. The global accuracy of plasma pTau217 using a two-threshold approach was robust in symptomatic groups, exceeding 90%. CONCLUSION: The evaluation of blood biomarkers on an automated platform exhibited high diagnostic accuracy for AD pathophysiology, and pTau217 showed excellent diagnostic accuracy to identify participants with AD in a consecutive sample representing the routine clinical practice in a specialized memory unit.

20.
Eur Respir J ; 40(2): 436-41, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22183489

ABSTRACT

This before-after study aimed to evaluate the effect of two interventions on lowering the prescription of antibiotics in lower respiratory tract infections (LRTI) in Spain. General practitioners (GPs) registered all cases with LRTIs over 3-week periods before and after an intervention, in 2008 and 2009. Two types of intervention were considered: full-intervention group (FIG), consisting of discussion sessions of the results of the first registry, courses for GPs, guidelines, patient information leaflets, workshops on rapid tests and use of the C-reactive protein (CRP) test; GPs in the partial-intervention group (PIG) underwent all of the above interventions except for the workshop on rapid tests, and they did not have access to CRP. A multilevel logistic regression analysis was performed considering the prescription of an antibiotic as the dependent variable. 210 physicians were assigned to FIG and 70 to PIG. In 2009, 58 new physicians were included as a control group. 5,385 LRTIs were registered. Compared with the control group, the OR of antibiotic prescription after the intervention in the PIG was 0.42 (95% CI: 0.22-0.82) and 0.22 (95% CI: 0.12-0.38) in the FIG. Intervention led to a reduction in the prescription of antibiotics, mainly when CRP testing was available.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Respiratory Tract Infections/drug therapy , C-Reactive Protein/metabolism , Case-Control Studies , Communication , Drug Prescriptions , Drug Utilization , General Practitioners , Humans , Practice Patterns, Physicians' , Primary Health Care/organization & administration , Prospective Studies , Regression Analysis , Spain
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