A pilot study of volumetric and density tumor analysis of ACC patients treated with vorinostat in a phase II clinical trial.

Rationale and objectives: Adenoid cystic carcinoma (ACC) is a rare salivary gland cancer. The vast majority of clinical trials evaluating systemic therapy efficacy in solid tumors use the Response Evaluation Criteria in Solid Tumors (RECIST) to measure response that is limited to 2 dimensional only evaluations, not taking volume or density into account. The indolent behavior ACC represents a challenge toward an appropriate evaluation of therapy response. Objectives: 1) To describe and contrast volumetric and density changes at each time-point, including changes noted from baseline to best response, to currently used 2 dimensional-only criteria (RECIST) and 2) To report the coefficient of variation in volume measurement among three reviewers on a subset of ACC patients. Materials and methods: We retrospectively assessed a cohort of 18 prospectively treated patients with ACC in a phase 2 trial with vorinostat using a volumetric (viable tumor volume, VTV) and density criteria. Three independent and blinded observers segmented target lesions across a sample of randomly selected computed tomography (CT) exams to examine inter-observer variation. Results: We found that the average coefficient of variation among observers for all target lesions was 16.1%, with lung lesions displaying a smaller variation at 14.0% (p-value >0.17). We describe examples of decrease in volume and density in several lesions despite stable disease by RECIST. Conclusion: This pilot study demonstrates that two-dimensional criteria such as RECIST may not be the best criteria to assess response to therapy, especially with evolving tools within picture archiving and communication system (PACS) that can assess volumetric size, density and texture, however, this should be prospectively studied.

A surveillance program for long-term central venous access-associated infections in outpatient chemotherapy services.

OBJECTIVE: In this study, we described the first results of a surveillance system for infections associated with long-term central venous catheters (LT-CVC) in patients under outpatient chemotherapy. DESIGN: This was a multicentric, prospective study. SETTING: Outpatient chemotherapy services. PARTICIPANTS: The study included 8 referral cancer centers in the State of São Paulo. INTERVENTION: These services were invited to participate in a newly created surveillance program for patients under chemotherapy. Several meetings were convened to share previous experiences on LT-CVC infection surveillance and to define the surveillance method. Once the program was implemented, all bloodstream infection (LT-CVC BSIs), tunnel infection, and exit-site infections associated with LT-CVC were reported. Data from January to May 2021 were analyzed. The median monthly number of chemotherapy sessions per clinic was 925 (IQR, 270-5,855). We used Poisson regression to analyze the association of rates with the characteristics of the services. RESULTS: In total, 107 LT-CVC infections were reported, of which 95% were BSIs, mostly associated with totally implantable devices (76%). Infections occurred a median of 4 days after the last catheter manipulation and 116 after the LT-CVC insertion. Also, 102 microorganisms were isolated from LT-CVC BSIs; the most common pathogen was Staphylococcus epidermidis, at 22%. Moreover, 44 infections (44%) fulfilled the criteria for CVC-related LT-CVC BSI and 27 infections (27%) met the criteria for mucosal barrier injury. The 1-year cumulative LT-CVC BSI rate was 1.94 per 1,000 CVC days of use. The rates were higher in public hospitals (IRR, 6.00; P < .001) and in hospitals that already had in place surveillance for LT-CVC infections (IRR, 2.01; P < .01). CONCLUSION: Our study describes an applicable surveillance method for infections in cancer outpatients using LT-CVC.

Using PDX animal models to identify and stratify adenoid cystic carcinoma patients presenting an enhanced response to HDAC inhibitors.

Adenoid cystic carcinoma (ACC) patients face a highly infiltrative and metastatic disease characterized by poor survival rates and suboptimal response to available therapies. We have previously shown that sensitization of ACC tumors to chemotherapy using histone deacetylase inhibitors (HDACi) constitutes a promising therapeutic strategy to manage tumor growth. Here, we used patient-derived xenografts (PDX) from ACC tumors to evaluate the effects of in vivo administration of the HDAC inhibitor Entinostat combined with Cisplatin over tumor growth. RNA from PDX tumor samples receiving the proposed therapy were analyzed using NanoString technology to identify molecular signatures capable of predicting ACC response to the therapy. We also used an RNAseq dataset from 68 ACC patients to validate the molecular signature identified by the NanoString platform. We found that the administration of Entinostat combined with Cisplatin resulted in a potent tumor growth inhibition (TGI) ranging from 38% to 106% of the original tumor mass. Enhanced response to therapy is consistent with the reactivation of tumor suppressor genes, including SFRP1, and the downregulation of oncogenes like FGF8 and CCR7. Nanostring data from PDX tumors identified a genetic signature capable of predicting tumor response to therapy. We further stratified 68 ACC patients containing RNAseq data accordingly to the activity levels of the identified genetic signature. We found that 23% of all patients exhibit a genetic signature consistent with a high ACC tumor response rate to Entinostat and Cisplatin. Our study provides compelling preclinical data supporting the deployment of a powerful systemic anticancer therapy crafted and explicitly tested for ACC tumors.

Drug-drug interactions of immunosuppressants and other drugs in kidney post-transplant recipients

Introduction: Immunosuppressants (ISS) are the most crucial tools used in the therapeutic regimens of transplant recipients. Nevertheless, these drugs are not the only ones adopted by patients; therefore, knowing the possible drug-drug interactions (DDIs) between immunosuppressants and other drugs commonly used in kidney transplant recipients is essential to ensure the effectiveness and safety of treatments. In this way, the objective is analyzing the DDIs between the immunosuppressants and other commonly used medications on kidney transplant adult recipients with active medical records undergoing post-transplant follow-up for 4.4 years (mean). Methods: First, we performed a cross-sectional study based on patients' records, in which the patient's profile and drugs used were examined, and after we analyzed DDIs by the Micromedex Drug Interactions® database. Results: We analyzed 176 patients with a mean age of 47.6(± 12.5); most were male (67.7%), and the majority received a kidney from a deceased donor (81.4%). Patients were exposed to 15.0 (± 5.4) different medicines after the transplantation, and 7.4 (± 4.0) of these medicines were simultaneous. After analyzing the DDIs according to the severity of interaction, documentation quality interaction effect, clinical management and probable interaction mechanism, the most frequent interaction was with tacrolimus, classified as moderate, and the 3 major causes of interaction occurred with azathioprine according to the Micromedex database. The primary medicines involved with immunosuppressant interactions were proton pump inhibitors, ranitidine, domperidone, amlodipine, enalapril, allopurinol, cyclobenzaprine, amitriptyline, fluoxetine, and ciprofloxacin. These DDIs' effects were related to, mainly, increase their immunosuppressant activity. Conclusion: Although the immunosuppressants analyzed lacked many clinical DDIs significance with other medicines, the healthcare team needs to monitor their DDIs' effects to prevent and minimize side effects in transplanted recipients.

Do varsity college athletes have a greater likelihood of risky alcohol and cannabis use than non-athletes? Results from a National Survey in Brazil

Objective: We examined the prevalence of risky alcohol and cannabis use among Brazilian varsity college athletes and whether this group had a greater likelihood of risky use than non-athletes. Methods: In 2009, Brazilian college students (n=12,711) were recruited for a national stratified random survey. Their sociodemographic characteristics, mental health, substance use, and participation in varsity sports were assessed. Binary logistic regression models were used to examine the association between varsity athlete status and moderate to high-risk alcohol and cannabis use. Results: Among varsity athletes, 67.6 and 10.7% reported risky alcohol and cannabis use, respectively. Varsity athletes had greater odds of risky alcohol consumption than non-athletes (aOR = 2.02, 95%CI 1.08-3.78). Varsity athletes also had greater odds of risky cannabis use than non-athletes in unadjusted analyses (OR = 2.57, 95%CI 1.05-6.28), although this relationship was attenuated after covariate adjustment. Conclusions: Among college students in Brazil, varsity athletes had a higher prevalence of risky alcohol and cannabis use than non-athletes. The rates were considerably higher than those observed among samples of U.S. college athletes. Future research should examine the use of these substances among varsity college athletes in other middle-income countries since these findings will likely guide prevention and treatment efforts.

Pembrolizumab induces HIV latency reversal in people living with HIV and cancer on antiretroviral therapy.

In people living with HIV (PLWH) on antiretroviral therapy (ART), virus persists in a latent form where there is minimal transcription or protein expression. Latently infected cells are a major barrier to curing HIV. Increasing HIV transcription and viral production in latently infected cells could facilitate immune recognition and reduce the pool of infected cells that persist on ART. Given that programmed cell death protein 1 (PD-1) expressing CD4+ T cells are preferentially infected with HIV in PLWH on ART, we aimed to determine whether administration of antibodies targeting PD-1 would reverse HIV latency in vivo. We therefore evaluated the impact of intravenous administration of pembrolizumab every 3 weeks on HIV latency in 32 PLWH and cancer on ART. After the first infusion of anti-PD-1, we observed a median 1.32-fold increase in unspliced HIV RNA and 1.61-fold increase in unspliced RNA:DNA ratio in sorted blood CD4+ T cells compared to baseline. We also observed a 1.65-fold increase in plasma HIV RNA. The frequency of CD4+ T cells with inducible virus evaluated using the tat/rev limiting dilution assay was higher after 6 cycles compared to baseline. Phylogenetic analyses of HIV env sequences in a participant who developed low concentrations of HIV viremia after 6 cycles of pembrolizumab did not demonstrate clonal expansion of HIV-infected cells. These data are consistent with anti-PD-1 being able to reverse HIV latency in vivo and support the rationale for combining anti-PD-1 with other interventions to reduce the HIV reservoir.

Quality of service and commitment to tobacco dependence treatment for individuals living with mental disorders in France: A pilot study.

BACKGROUND: There are remarkably high smoking rates in patients living with mental disorders (PLWMD), and the absence of a specific treatment policy for smoking cessation for these patients worldwide. The present study aimed to (i) investigate the quality of service and commitment to tobacco dependence treatment, and (ii) produce high-quality French versions of the Index of Tobacco Treatment Quality (ITTQ) and Tobacco Treatment Commitment Scale (TTCS). METHODS: ITTQ and TTCS were used to assess French mental health professionals (n = 80). Both scales were translated from their original language following standard procedures (i.e. forward translation). Descriptive analysis for total score, each factor and item were calculated for the entire sample, followed by subgroup analysis by gender, and role of the practitioner. RESULTS: Nurses presented higher levels of both treatment commitment and treatment quality in their mental health care units, compared to psychiatrists, and residents. Overall, counseling offering was low and there was a perception that it is unfair to take tobacco away from PLWMD. In the other hand, there were high levels of smoking assessment and perceptions that nicotine dependence should be included in drug treatment programs. CONCLUSIONS: There is a gap in tobacco treatment implementation for French PLWMD. The present pilot study alerts about the problem, and should stimulate larger studies validating such measures for wide use with French-speaking mental health professionals. French nurses presented higher levels of both treatment commitment and quality, and could be in a leadership position for such implementation. Encouraging the implementation of tobacco counseling within conventional mental health treatment is critical to improve cessation rates among this population. There is a potential for the sustainability of tobacco treatment interventions since the levels of commitment observed here were higher than in previous studies conducted abroad.

Safety, Activity, and Long-term Outcomes of Pomalidomide in the Treatment of Kaposi Sarcoma among Individuals with or without HIV Infection.

PURPOSE: Kaposi sarcoma (KS) is caused by Kaposi sarcoma herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8). KS, which develops most frequently among people with HIV, is generally treated with chemotherapy, but these drugs have acute and cumulative toxicities. We previously described initial results of a trial of pomalidomide, an oral immunomodulatory derivative of thalidomide, in patients with KS. Here, we present results on the full cohort and survival outcomes. PATIENTS AND METHODS: Participants with KS with or without HIV were treated with pomalidomide 5 mg once daily for 21 days per 28-day cycle with aspirin 81 mg daily for thromboprophylaxis. Participants with HIV received antiretroviral therapy. Response was defined by modified version of the AIDS Clinical Trial Group KS criteria. We evaluated tumor responses (including participants who had a second course), adverse events, progression-free survival (PFS), and long-term outcomes. RESULTS: Twenty-eight participants were enrolled. Eighteen (64%) were HIV positive and 21 (75%) had advanced (T1) disease. The overall response rate was 71%: 95% confidence interval (CI) 51%-87%. Twelve of 18 HIV-positive (67%; 95% CI, 41-87%) and 8 of 10 HIV-negative participants (80%; 95% CI, 44%-97%) had a response. Two of 4 participants who received a second course of pomalidomide had a partial response. The median PFS was 10.2 months (95% CI: 7.6-15.7 months). Grade 3 neutropenia was noted among 50% of participants. In the follow-up period, 3 participants with HIV had other KSHV-associated diseases. CONCLUSIONS: Pomalidomide is a safe and active chemotherapy-sparing agent for the treatment of KS among individuals with or without HIV.

Corrigendum: Substance Use in Mild-COVID-19 Patients: A Retrospective Study.

[This corrects the article DOI: 10.3389/fpubh.2021.634396.].

Substance Use in Mild-COVID-19 Patients: A Retrospective Study.

Background: There is a need for prospective studies investigating substance use variations in mild COVID-19 patients. These individuals represent the majority of patients affected by the disease and are routinely treated at home, facing periods of quarantine. Methods: This was a retrospective cohort study. All people who tested positive for COVID-19 and classified as mild cases (i.e., no alarm sign/symptom, no need for in-person consultation) during the treatment in the public health system of a Brazilian city with around 160,000 inhabitants were monitored by phone for all the COVID-19 symptoms listed by the Centers for Disease Control and Prevention (CDC) during the active phase of the disease (i.e., no longer experiencing symptoms, up to 14 days in mild cases). After this phase (median = 108 days after intake, IQR = 76-137), we asked these patients who were classified as experiencing mild COVID-19 (n = 993) about last-month substance use in three time-points: pre-COVID, just after COVID-19 acute phase (post-COVID acute phase) and in the period before survey (post-COVID follow-up phase). Results: The number of COVID-19 symptoms was not associated with pre- or post-infection substance use. Pre-COVID alcohol and non-medical benzodiazepine use were associated with specific COVID-19 symptoms. However, sensitivity analyses showed that such associations could be explained by previous psychiatric and medical profiles. Alcohol and tobacco use decreased and non-medical analgesics increased in the post-COVID acute phase. However, just alcohol use remained lower in the post-COVID follow-up period. Higher pre-COVID levels of tobacco and alcohol were associated with post-COVID follow-up cannabis and non-medical analgesic use, respectively. Non-medical benzodiazepine use had positive and negative bi-directional associations with cannabis and non-medical analgesic use, respectively. Conclusion: We were not able to find specific associations between substance use and COVID-19 symptomatology in the present study. Patients with mild COVID-19 should be monitored for substance use in the post-COVID-19 period, and preventive interventions for non-medical analgesic use should be implemented. Focused preventive interventions increasing the perceived risks of cannabis and non-medical benzodiazepine and analgesic use among people experiencing mild COVID-19 that reported previous substance use could be useful.

Characteristics and outcomes of KSHV-associated multicentric Castleman disease with or without other KSHV diseases.

Kaposi sarcoma (KS)-associated herpesvirus (KSHV)-associated multicentric Castleman disease (MCD) is a relapsing and remitting systemic lymphoproliferative disorder characterized by severe inflammatory symptoms most common among people living with HIV (PLWH). Patients with KSHV-MCD may present with concurrent KSHV-associated diseases, such as KS and/or primary effusion lymphoma (PEL). We evaluated clinical and immunologic characteristics, the effects of concurrent KSHV malignancies, and treatments from the largest prospective natural history study of participants with KSHV-MCD within the United States. Treatment options administered at investigator discretion included high-dose zidovudine with valganciclovir (AZT/VGC), rituximab, or rituximab with liposomal doxorubicin (R-Dox) during KSHV-MCD flares. Survival analyses and prognostic factors were explored for all participants. Sixty-two participants with HIV were enrolled, including 20 with KSHV-MCD alone, 34 with KSHV-MCD and KS, 1 with KSHV-MCD and PEL, and 7 with all KSHV-associated diseases. Forty-four percent of KSHV-MCD diagnoses were made at our institution. Forty-four participants received rituximab-based therapies, 20 of whom had maintenance AZT/VGC or interferon. Participants receiving R-Dox and then maintenance AZT/VGC had the highest 5-year progression-free survival (89%). Cytokine profiles during KSHV-MCD flares did not differ by the presence of concurrent KSHV-associated diseases. The 10-year survival was 71% (95% confidence interval [CI], 56% to 82%) for all participants. A concurrent diagnosis of PEL negatively impacted survival (PEL hazard ratio, 5.4; 95% CI, 1.8 to 16.8). KSHV-MCD is an underdiagnosed condition among PLWH, including those with KS. KSHV-MCD has an excellent prognosis with appropriate treatment. Physicians should be alert for patients with multiple KSHV diseases, which impact optimal treatment and survival outcomes. This study was registered at www.clinicaltrials.gov as #NCT00099073.

Occurrence of polar organic compounds in atmospheric particulate matter: a system review in South America.

Particulate matter (PM) is one of the existing air pollutants, which can cause damages to human health, public property, and the environment. The chemical composition of this pollutant greatly varies, mainly its organic fraction. Thus, our objective was to carry out a literature review based on articles, considering studies conducted in South America, whose authors address the characterization of the polar organic fraction of PM. We performed the review using the Scopus, SciELO, and Web of Science databases, considering publications dated from the years 2010 to 2019. A total of 14,575 articles were found, of which only 12 met the predefined selection criteria. According to our research, the most studied compound is levoglucosan, a biomass burning marker belonging to the group of anhydrous sugars. Besides, nitro-PAHs, which usually originate from vehicular sources and are compounds with mutagenic and carcinogenic characteristics, have also been found. Moreover, we concluded that, currently, there are few studies on the subject in South America, requiring more research on polar organic compounds present in PM in countries of this region. These studies are of great importance because some compounds can cause great damage to human health, such as the nitro-PAHs; furthermore, PM may still have unknown compounds that need identification and elucidation of their toxicity.

Exploratory study on the psychological impact of COVID-19 on the general Brazilian population.

The COVID-19 pandemic has become one of the main international concerns regarding its impact on mental health. The present study aims to investigate the prevalence of depression, anxiety, and stress symptoms, and behavioral aspects amidst the COVID-19 pandemic in a Brazilian population. An online survey was administered from May 22 to June 5, 2020 using a questionnaire comprising of sociodemographic information, the Depression, Anxiety, and Stress Scale (DASS-21), and the Coping Strategies Inventory. Participants comprised 3,000 people from Brazil's 26 states and the Federal District, with an average age of 39.8 years, women (83%), married (50.6%), graduates (70.1%) and employees (46.7%). Some contracted the virus (6.4%) and had dead friends or relatives (22.7%). There was more consumption of drugs, tobacco, medication, and food (40.8%). Almost half of participants expressed symptoms of depression (46.4%), anxiety (39.7%), and stress (42.2%). These were higher in women, people without children, students, patients with chronic diseases, and people who had contact with others diagnosed with COVID-19. The existence of a group more vulnerable to situations with a high stress burden requires greater attention regarding mental health during and after the pandemic. That said, it should be emphasized that these findings are preliminary and portray a moment still being faced by many people amid the pandemic and quarantine measures. Therefore, we understand that the magnitude of the impacts on mental health will only be more specific with continuous studies after total relaxation of the quarantine.

Use of pembrolizumab with or without pomalidomide in HIV-associated non-Hodgkin's lymphoma.

BACKGROUND: Non-Hodgkin's lymphoma (NHL) is currently the most common malignancy among people living with HIV (PLWH) in the USA. NHL in PLWH is more frequently associated with oncogenic viruses than NHL in immunocompetent individuals and is generally associated with increased PD-1 expression and T cell exhaustion. An effective immune-based second-line approach that is less immunosuppressive than chemotherapy may decrease infection risk, improve immune control of oncogenic viruses, and ultimately allow for better lymphoma control. METHODS: We conducted a retrospective study of patients with HIV-associated lymphomas treated with pembrolizumab±pomalidomide in the HIV and AIDS Malignancy Branch, Center for Cancer Research, National Cancer Institute. RESULTS: We identified 10 patients with stage IV relapsed and/or primary refractory HIV-associated NHL who were treated with pembrolizumab, an immune checkpoint inihibitor, with or without pomalidomide. Five patients had primary effusion lymphoma (PEL): one had germinal center B cell-like (GCB) diffuse large B cell lymphoma (DLBCL); two had non-GCB DLBCL; one had aggressive B cell lymphoma, not otherwise specified; and one had plasmablastic lymphoma. Six patients received pembrolizumab alone at 200 mg intravenously every 3 weeks, three received pembrolizumab 200 mg intravenously every 4 weeks plus pomalidomide 4 mg orally every day for days 1-21 of a 28-day cycle; and one sequentially received pembrolizumab alone and then pomalidomide alone. The response rate was 50% with particular benefit in gammaherpesvirus-associated tumors. The progression-free survival was 4.1 months (95% CI: 1.3 to 12.4) and overall survival was 14.7 months (95% CI: 2.96 to not reached). Three patients with PEL had leptomeningeal disease: one had a complete response and the other two had long-term disease control. There were four immune-related adverse events (irAEs), all CTCAEv5 grade 2-3; three of the four patients were able to continue receiving pembrolizumab. No irAEs occurred in patients receiving the combination of pembrolizumab and pomalidomide. CONCLUSIONS: Treatment of HIV-associated NHL with pembrolizumab with or without pomalidomide elicited responses in several subtypes of HIV-associated NHL. This approach is worth further study in PLWH and NHL.

Modulation rate and age effect on intermittent speech recognition / Efeito da idade e da taxa de modulação no reconhecimento da fala intermitente

ABSTRACT Purpose: to investigate the auditory recognition of intermittent speech in relation to different modulation rates and ages. Methods: 20 young people, 20 middle-aged adults, and 16 older adults, all of them with auditory thresholds equal to or lower than 25 dB HL up to the frequency of 4000 Hz. The participants were submitted to intermittent speech recognition tests presented in three modulation conditions: 4 Hz, 10 Hz, and 64 Hz. The percentages of correct answers were compared between age groups and modulation rates. ANOVA and post hoc tests were conducted to investigate the modulation rate effect, and the mixed linear regression model (p < 0.001). Results: regarding the age effect, the data showed a significant difference between young people and older adults, and between middle-aged and older adults. As for the modulation rate effect, the indexes of correct answers were significantly lower at the slower rate (4 Hz) in the three age groups. Conclusion: an age effect was verified on intermittent speech recognition: older adults have greater difficulty. A modulation rate effect was also noticed in the three age groups: the higher the rate, the better the performance.

RESUMO Objetivo: investigar o reconhecimento auditivo da fala intermitente em função de diferentes taxas de modulação e em função da idade. Métodos: participaram do estudo vinte jovens, vinte adultos de meia idade, e dezesseis idosos, todos com limiares auditivos iguais ou menores que 25 dB NA até a frequência de 4000 Hz. Os participantes foram submetidos a testes de reconhecimento da fala intermitente apresentada em três condições de modulação: 4 Hz, 10 Hz e 64 Hz. Percentuais de acerto foram comparados entre grupos etários e taxas de modulação. Para a investigação do efeito da taxa de modulação foi realizada ANOVA e testes Post Hoc, enquanto para a investigação do efeito da idade, utilizou-se o modelo de regressão linear misto (p<0,001). Resultados: sobre o efeito da idade, os dados mostram diferença significante entre jovens e idosos, e entre adultos de meia idade e idosos. Sobre o efeito da taxa de modulação, os índices de acerto da taxa mais lenta (4Hz) foram significantemente menores nos três grupos etários. Conclusão: foi verificado um efeito da idade no reconhecimento da fala intermitente: idosos apresentaram maior dificuldade. Percebeu-se também um efeito de taxa de modulação nos três grupos etários: quanto maior a taxa, melhor o desempenho.

Challenges and Advances in Antemortem Diagnosis of Human Transmissible Spongiform Encephalopathies.

Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, arise from the structural conversion of the monomeric, cellular prion protein (PrPC) into its multimeric scrapie form (PrPSc). These pathologies comprise a group of intractable, rapidly evolving neurodegenerative diseases. Currently, a definitive diagnosis of TSE relies on the detection of PrPSc and/or the identification of pathognomonic histological features in brain tissue samples, which are usually obtained postmortem or, in rare cases, by brain biopsy (antemortem). Over the past two decades, several paraclinical tests for antemortem diagnosis have been developed to preclude the need for brain samples. Some of these alternative methods have been validated and can provide a probable diagnosis when combined with clinical evaluation. Paraclinical tests include in vitro cell-free conversion techniques, such as the real-time quaking-induced conversion (RT-QuIC), as well as immunoassays, electroencephalography (EEG), and brain bioimaging methods, such as magnetic resonance imaging (MRI), whose importance has increased over the years. PrPSc is the main biomarker in TSEs, and the RT-QuIC assay stands out for its ability to detect PrPSc in cerebrospinal fluid (CSF), olfactory mucosa, and dermatome skin samples with high sensitivity and specificity. Other biochemical biomarkers are the proteins 14-3-3, tau, neuron-specific enolase (NSE), astroglial protein S100B, α-synuclein, and neurofilament light chain protein (NFL), but they are not specific for TSEs. This paper reviews the techniques employed for definite diagnosis, as well as the clinical and paraclinical methods for possible and probable diagnosis, both those in use currently and those no longer employed. We also discuss current criteria, challenges, and perspectives for TSE diagnosis. An early and accurate diagnosis may allow earlier implementation of strategies to delay or stop disease progression.