Mexican Patients Research Articles

Mycetoma due to Nocardia brasiliensis (Maduromycosis) in the Mixteca Poblana: Case report with successful treatment

The case of a Mexican patient of the Mixteca Poblana, Region until today little studied, dedicated to domestic work with a skin infection caused by Nocardia brasiliensis, which evolved favorably despite taking more than 8 years with the injury is presented. The diagnosis was made by direct examination and culture of the specimen. The mycetoma is a progressive chronic localized infection caused by fungi or bacteria that affects the feet, upper limbs or back. The symptoms of the case include: edema, fistuous formation. The diagnosis is clinical, confirmed with microscopic examination of exudate and culture. The treatment consists of antibiotics for a long time 21 days central intensive phase and one year with supportive treatment orally and locally.

A Review of Disparities and Unmet Newborn Screening Needs over 33 Years in a Cohort of Mexican Patients with Inborn Errors of Intermediary Metabolism.

Advances in an early diagnosis by expanded newborn screening (NBS) have been achieved mainly in developed countries, while populations of middle- and low-income countries have poor access, leading to disparities. Expanded NBS in Mexico is not mandatory. Herein, we present an overview of the differences and unmet NBS needs of a group of Mexican patients with inborn errors of intermediary metabolism (IEiM), emphasizing the odyssey experienced to reach a diagnosis. We conducted a retrospective observational study of a historical cohort of patients with IEiM from a national reference center. A total of 924 patients with IEiM were included. Although 72.5% of the diseases identified are detectable by expanded NBS, only 35.4% of the patients were screened. The mortality in the unscreened group was almost two-fold higher than that in the screened group. Patients experienced a median diagnostic delay of 4 months, which is unacceptably long considering that to prevent disability and death, these disorders must be treated in the first days of life. Patients had to travel long distances to our reference center, contributing to their unacceptable diagnostic odyssey. This study highlights the urgent need to have an updated, expanded NBS program with adequate follow up in Mexico and promote the creation of regional medical care centers. We also provide compelling evidence that could prove valuable to decision makers overseeing public health initiatives for individuals impacted by IEiM from middle- and low-income countries.

Circulating miRNAs as Noninvasive Biomarkers for PDAC Diagnosis and Prognosis in Mexico.

Among malignant neoplasms, pancreatic ductal adenocarcinoma (PDAC) has one of the highest fatality rates due to its late detection. Therefore, it is essential to discover a noninvasive, early, specific, and sensitive diagnostic method. MicroRNAs (miRNAs) are attractive biomarkers because they are accessible, highly specific, and sensitive. It is crucial to find miRNAs that could be used as possible biomarkers because PDAC is the eighth most common cause of cancer death in Mexico. With the help of microRNA microarrays, differentially expressed miRNAs (DEmiRNAs) were found in PDAC tissues. The presence of these DEmiRNAs in the plasma of Mexican patients with PDAC was determined using RT-qPCR. Receiver operating characteristic curve analysis was performed to determine the diagnostic capacity of these DEmiRNAs. Gene Expression Omnibus datasets (GEO) were employed to verify our results. The Prisma V8 statistical analysis program was used. Four DEmiRNAs in plasma from PDAC patients and microarray tissues were found. Serum samples from patients with PDAC were used to validate their overexpression in GEO databases. We discovered a new panel of the two miRNAs miR-222-3p and miR-221-3p that could be used to diagnose PDAC, and when miR-221-3p and miR-222-3p were overexpressed, survival rates decreased. Therefore, miR-222-3p and miR-221-3p might be employed as noninvasive indicators for the diagnosis and survival of PDAC in Mexican patients.

Celiac disease seroprevalence in subjects with dyspeptic symptoms. A study on a Mexican population

Introduction and aimsCeliac disease (CD) is an autoimmune enteropathy that develops in genetically susceptible individuals. The typical gastrointestinal manifestation is diarrhea but symptoms of dyspepsia, such as epigastric pain, nausea, or satiety, can sometimes appear. Previous studies have reported that the prevalence of CD in patients with dyspepsia can be as high as 7%. The aim of the present study was to evaluate CD seroprevalence in subjects with dyspeptic symptoms and a control group in a Mexican population. Material and methodsA case-control study was conducted on blood donors that answered the PAGI-SYM questionnaire for dyspepsia and in whom IgA antibodies to tissue transglutaminase 2 (IgA anti-tTG2) and IgG antibodies to deamidated gliadin peptide (IgG anti-DGP) were determined. CD seroprevalence in subjects with dyspeptic symptoms and in asymptomatic subjects was compared. ResultsA total of 427 subjects (76.3% men), with a mean patient age of 34 years (range of 18–65 years) were included. Of those participants, 87 (20.3%) had symptoms of dyspepsia (group A) and 340 (79.6%) were asymptomatic (group B). Antibodies were positive in one (1.15%) of the group A subjects (1/87, 95% CI 0.2–6 %), whereas they were positive in 4 (1.18%) of the group B subjects (4/340, 95% CI 0.4–2.9%, p = 0.59). ConclusionsCD seroprevalence in the study population with dyspeptic symptoms (1%) was not different from that of the control population. Thus, CD screening in Mexican patients with dyspepsia is not justified.

Fecal Microbial Composition and Predicted Functional Profile in Irritable Bowel Syndrome Differ between Subtypes and Geographical Locations.

Increasing evidence suggests a microbial pathogenesis in irritable bowel syndrome (IBS) but the relationship remains elusive. Fecal DNA samples from 120 patients with IBS, 82 Mexican (IBS-C: n = 33, IBS-D: n = 24, IBS-M: n = 25) and 38 British (IBS-C: n = 6, IBS-D: n = 27, IBS-M: n = 5), were available for analysis using 16S rRNA gene sequencing. Firmicutes (mean: 82.1%), Actinobacteria (10.2%), and Bacteroidetes (4.4%) were the most abundant taxa. The analysis of all samples (n = 120), and females (n = 94) only, showed no significant differences in bacterial microbiota, but the analysis of Mexican patients (n = 82) showed several differences in key taxa (e.g., Faecalibacterium) among the different IBS subtypes. In IBS-D there were significantly higher Bacteroidetes in British patients (n = 27) than in Mexican patients (n = 24), suggesting unique fecal microbiota signatures within the same IBS subtype. These differences in IBS-D were also observed at lower phylogenetic levels (e.g., higher Enterobacteriaceae and Streptococcus in Mexican patients) and were accompanied by differences in several alpha diversity metrics. Beta diversity was not different among IBS subtypes when using all samples, but the analysis of IBS-D patients revealed consistent differences between Mexican and British patients. This study suggests that fecal microbiota is different between IBS subtypes and also within each subtype depending on geographical location.

Observational analysis of clinical and pathological characteristics and their prognostic impact in Mexican patients with breast cancer: A multi-center study.

Breast cancer is the most incidental and deadly neoplasm worldwide; in Mexico, very few epidemiologic reports have analyzed the pathological features and its impact on their clinical outcome. Here, we studied the relation between pathological features and the clinical presentation at diagnosis and their impact on the overall and progression-free survival of patients with breast cancer. For this purpose, we collected 199 clinical records of female patients, aged at least 18 years old (y/o), with breast cancer diagnosis confirmed by biopsy. We excluded patients with incomplete or conflicting clinical records. Afterward, we performed an analysis of overall and progression-free survival and associated risks. Our results showed an average age at diagnosis of 52 y/o (24-85), the most common features were: upper outer quadrant tumor (32%), invasive ductal carcinoma (76.8%), moderately differentiated (44.3%), early clinical stages (40.8%), asymptomatic patients (47.8%), luminal A subtype (47.8%). Median overall survival was not reached, but median progression-free survival was 32.2 months (29.75-34.64, CI 95%) associated risk were: clinical stage (p <0.0001) symptomatic presentation (p =0.009) and histologic grade (p =0.02). Therefore, we concluded that symptom presence at diagnosis impacts progression-free survival, and palpable symptoms are related to an increased risk for mortality.

SAT603 A Heterogeneous Genetic Background Underlies Familial And Young-onset Pituitary Tumors

Abstract Disclosure: J.M. Zuarth-Vazquez: None. R.G. Rebollar-Vega: None. C. Ramírez-Rentería: None. W.E. Hernández-Núñez: None. M. Torres-Morán: None. A.L. Franco-Álvarez: None. J. Eseiza-Acevedo: None. M. Aguilar-Soto: None. D. Cuevas-Ramos: None. E. Sosa-Eroza: None. M. Mercado: None. A. Gamboa-Dominguez: None. L.C. Hernández-Ramírez: None. Introduction: Inherited pituitary neuroendocrine tumors (PitNETs) are considered rare and may present either as isolated lesions or in association with other endocrine tumors. Despite significant progress in the understanding of their molecular basis, the precise pathophysiological mechanisms in many patients with familial and sporadic pituitary tumors are unknown. Although the clinical presentation may point towards a specific genetic cause, a combination of careful clinical assessment and state-of-the-art genetic testing is required. Objective: To describe 4 cases of PitNETs with heterogeneous clinical presentations and genetic causes from a cohort of Mexican patients with neuroendocrine tumors. Methodology: Patients were recruited under informed consent from two different reference hospitals in Mexico City. Germline genetic testing was performed using either a custom-made or a commercial next-generation sequencing (NGS) panel. When available, relevant variants were confirmed in tissue samples. Genetic results were correlated with clinical, biochemical, and imaging characteristics. Results: Case 1 is an 18-year-old male with gigantism due to a 3-cm GH/prolactin-secreting PitNET, that was not cured after transsphenoidal surgery (TSS). Genetic testing showed a CDKN1B (NM_004064.5) c.356T&amp;gt;C, p.I119T variant of uncertain significance. No relevant family history was informed. Currently, the patient is treated with monthly octreotide LAR. Case 2 is a patient with young-onset acromegaly (15y) due to a GH-secreting PitNET. She was initially treated with bromocriptine and then underwent TSS without achieving remission. Radiotherapy was therefore indicated, resulting in panhypopituitarism. The likely pathogenic variant of AIP (NM_003977.4) c.872_877del, p.V291_L292del, was identified. Case 3 was diagnosed at the age of 15 with gigantism, treated with TSS and radiotherapy, subsequently demonstrating biochemical cure. Whole-exome sequencing showed the AIP pathogenic variant c.910C.T, p.R304*, indicative of familial isolated pituitary adenoma, confirmed by the history of two paternal first cousins with gigantism. Finally, a 54-year-old man (case 4), with a personal and family history of neurofibromatosis type 1, was incidentally diagnosed with a 16 mm, apparently non-functional PitNET, for which he is awaiting surgery. The pathogenic NF1 (NM_001042492.3) variant c.147C&amp;gt;A, p.Y49* was identified. Conclusions: Our data confirm that inherited PitNETs encompass a variety of clinical phenotypes. Modern NGS-based genetic testing is an effective method for identifying such cases. Precise molecular testing has an impact on the timely diagnosis of these lesions, as well as on their prognosis and the need for genetic counseling. Presentation: Saturday, June 17, 2023

Usability Evaluation of an Educational Website for Mexican Patients with Type 2 Diabetes: Satisfaction, Facility, and Utility

Diabetes education constitutes a pivotal component of treatment aimed at achieving and sustaining metabolic control. Health information technologies have demonstrated their effectiveness as tools for delivering health education. Nonetheless, only a limited number of reports have been published illustrating the usability of educational websites concerning type 2 diabetes (T2D). In this context, a cross-sectional study was carried out to assess the usability of an educational website across four primary care clinics in Mexico City. The study included ninety patients diagnosed with T2D, 71% of whom were women, and with a median diabetes diagnosis duration of 5 years. Parameters such as glucose levels, glycated hemoglobin (HbA1c), and anthropometric measurements were recorded. Additionally, the level of usability was gauged using a previously validated instrument, revealing that 78% of participants found the educational website highly usable.

Germline DNA Repair Genes Pathogenic Variants Among Mexican Patients With Prostate Cancer.

Early identification of germline mutation carriers may be relevant for the optimal management of prostate cancer and to inform cancer risk in relatives. However, population minorities have limited access to genetic testing. The aim of this study was to describe the frequency of DNA repair gene pathogenic variants (PVs) among Mexican men with prostate cancer referred for Genomic Cancer Risk Assessment and testing. Patients diagnosed with prostate cancer who meet criteria for genetic testing and enrolled in the Clinical Cancer Genomics Community Research Network at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán in Mexico City were included. Descriptive statistics were performed using frequency and proportions for categorical variables and median and range for quantitative variables. X2 and t test were used for group comparisons. A total of 199 men were enrolled, median age at diagnosis was 66 (range 44-88) years; 45% were de novo metastatic and 44% were high- very high and 10% were intermediate risk group. Four (2%) had a pathogenic germline variant; one each of the following genes: ATM, CHEK2, BRIP1, and MUTYH (all monoallelic). Younger men at diagnosis were more likely to carry a PV than older age at diagnosis (56.7 vs. 66.4 years, P=.01). Our results showed a low prevalence of known prostate cancer associated PVs and no BRCA PVs in Mexican men with prostate cancer. This suggests that the genetic and/or epidemiologic risk factors for prostate cancer are not well characterized in this specific population.

1169P Tumour transcriptional and spatial protein profiling in Mexican patients reveals that acral lentiginous melanoma is characterized by an immunosuppressive microenvironment

1169P Tumour transcriptional and spatial protein profiling in Mexican patients reveals that acral lentiginous melanoma is characterized by an immunosuppressive microenvironment

Disparities in Stage at Presentation among Hispanic and Latinx Patients with Non-Small Cell Lung Cancer

Hispanic and Latinx people in the United States comprise 19% of the population and are the fastest-growing ethnic group. However, prior studies in non-small cell lung cancer (NSCLC) often analyze these diverse communities in aggregate. We aimed to identify differences in NSCLC stage at diagnosis in the US population, with a particular focus on disaggregated Hispanic populations. Data from the National Cancer Database (NCDB) from 2004 to 2018 were used to identify patients with primary NSCLC. Individuals were disaggregated by racial and ethnic subgroup and Hispanic country of origin. Ordinal logistic regression adjusting for age, facility type, income, educational attainment, comorbidity index, insurance, and year of diagnosis was used to create adjusted odds ratios (aORs), with higher odds representing diagnosis at later-stage NSCLC. Out of 1,773,177 patients with NSCLC, 50,512 were Hispanic/Latinx (2.8%). Hispanic patients were less likely to be insured (χ2 P<0.001) and were more likely to live in lower-income ZIP codes (χ2 P<0.001). Hispanic patients were more likely to be diagnosed with metastatic disease compared to non-Hispanic White (NHW) patients: 47% for Hispanic Black (HB), 46% Hispanic White (HW), and 44.3% of Hispanic other (HO) patients vs. 39.1% of NHW patients (aORs for later-stage disease with NHW as reference: HW 1.23, HB 1.26, HO 1.14, P<0.001 for all). Upon disaggregation by country of origin, 51.4% of Mexican, 41.7% of Puerto Rican, 44.6% of Cuban, 50.8% of South or Central American, 48.4% of Dominican, and 45.6% of Other Hispanic patients were diagnosed with metastatic disease, compared with 39.1% of NHW patients. Conversely, 20.2% of Mexican, 26.9% of Puerto Rican, 24.2% of Cuban, 22.5% of South or Central American, 23.7% of Dominican, and 24.5% of Other Hispanic patients were diagnosed with stage I disease, compared with 30.0% of NHW patients. On multivariable analysis, all Hispanic groups were more likely to present with later-stage NSCLC than NHW patients, with the greatest odds for Mexican patients (aOR 1.45, P<0.001). Hispanic/Latinx patients with non-small cell lung cancer were more likely to be diagnosed with more advanced disease compared with non-Hispanic White patients. Disparities persisted upon disaggregation by both race and country of origin, with over half of Mexican patients with metastatic disease at diagnosis. Disparities amongst Hispanic groups by race and by country of origin highlight the shortcomings of treating these groups as a monolith and underscore the need for disaggregated research and targeted interventions. Further work should explore differences in exposures, behaviors, and access to care that may underlie these disparities.

Modified Early Warning Score: Clinical Deterioration of Mexican Patients Hospitalized with COVID-19 and Chronic Disease.

Retrospective observational study, 430 hospitalized patients with COVID-19 and chronic disease. Instrument, Modified Early Warning Score (MEWS). Data analysis, with Cox and logistic regression, to predict survival and risk. Of 430 patients, 58.6% survived, and 41.4% did not. The risk was: low 53.5%, medium 23.7%, and high 22.8%. The MEWS score was similar between survivors 3.02, p 0.373 (95% CI: -0.225-0.597) and non-survivors 3.20 (95% CI: -0.224-0.597). There is a linear relationship between MEWS and mortality risk R 0.920, ANOVA 0.000, constant 4.713, and coefficient 4.406. The Cox Regression p 0.011, with a risk of deterioration of 0.325, with a positive coefficient, the higher the risk, the higher the mortality, while the invasive mechanical ventilation coefficient was negative -0.757. By providing oxygen and ventilation, mortality is lower. The predictive value of the modified early warning score in patients hospitalized for COVID-19 and chronic disease is not predictive with the MEWS scale. Additional assessment is required to prevent complications, especially when patients are assessed as low-risk.

Genetic Variant HLA-DRB1*0403 and Therapeutic Response to Disease-Modifying Therapies in Multiple Sclerosis: A Case-Control Study.

Multiple sclerosis (MS) is a chronic and demyelinating disease with an autoimmune origin, which leads to neurodegeneration and progressive disability. Approximately 30 to 50% of patients do not respond optimally to disease-modifying therapies (DMTs), and therapeutic response may be influenced by genetic factors such as genetic variants. Therefore, our study aimed to investigate the association of the HLA-DRB1*0403 genetic variant and therapeutic response to DMTs in MS. We included 105 patients with MS diagnosis. No evidence of disease activity based on the absence of clinical relapse, disability progression or radiological activity (NEDA-3) was used to classify the therapeutic response. Patients were classified as follows: (a) controls: patients who achieved NEDA-3; (b) cases: patients who did not achieve NEDA-3. DNA was extracted from peripheral blood leukocytes. HLA-DRB1*0403 genetic variant was analyzed by quantitative polymerase chain reaction (qPCR) using TaqMan probes. NEDA-3 was achieved in 86.7% of MS patients treated with DMTs. Genotype frequencies were GG 50.5%, GA 34.3%, and AA 15.2%. No differences were observed in the genetic variant AA between patients who achieved NEDA-3 versus patients who did not achieve NEDA-3 (48.7% vs. 43.1%, p = 0.6). We concluded that in Mexican patients with MS, HLA-DRB1*0403 was not associated with the therapeutic response to DMTs.

Differences in Outcomes by Place of Origin among Hispanic Patients with Kidney Failure.

Hispanic patients are known to have a higher risk of kidney failure and lower rates of home dialysis use and kidney transplantation than non-Hispanic White patients. However, it is unknown whether these outcomes differ within the Hispanic community, which is heterogeneous in its members' places of origins. Using United States Renal Data System data, the authors found similar adjusted rates of home dialysis use for patients originating from places outside the United States and US-born Hispanic patients, whereas the adjusted risk of mortality and likelihood of transplantation differed depending on place (country or territory) of origin. Understanding the heterogeneity in kidney disease outcomes and treatment within the Hispanic community is crucial in designing interventions and implementation strategies to ensure that Hispanic individuals with kidney failure have equitable access to care. Compared with non-Hispanic White groups, Hispanic individuals have a higher risk of kidney failure yet lower rates of living donor transplantation and home dialysis. However, how home dialysis, mortality, and transplantation vary within the Hispanic community depending on patients' place of origin is unclear. We identified adult Hispanic patients from the United States Renal Data System who initiated dialysis in 2009-2017. Primary exposure was country or territory of origin (the United States, Mexico, US-Puerto Rico, and other countries). We used logistic regression to estimate differences in odds of initiating home dialysis and competing risk models to estimate subdistribution hazard ratios (SHR) of mortality and kidney transplantation. Of 137,039 patients, 44.4% were US-born, 30.9% were from Mexico, 12.9% were from US-Puerto Rico, and 11.8% were from other countries. Home dialysis rates were higher among US-born patients, but not significantly different after adjusting for demographic, medical, socioeconomic, and facility-level factors. Adjusted mortality risk was higher for individuals from US-Puerto Rico (SHR, 1.04; 95% confidence interval [CI], 1.01 to 1.08) and lower for Mexico (SHR, 0.80; 95% CI, 0.78 to 0.81) and other countries (SHR, 0.83; 95% CI, 0.81 to 0.86) compared with US-born patients. The adjusted rate of transplantation for Mexican or US-Puerto Rican patients was similar to that of US-born patients but higher for those from other countries (SHR, 1.22; 95% CI, 1.15 to 1.30). Hispanic people from different places of origin have similar adjusted rates of home dialysis but different adjusted rates of mortality and kidney transplantation. Further research is needed to understand the mechanisms underlying these observed differences in outcomes.

Rituximab in the treatment of multiple sclerosis. Experience of a tertiary care hospital in Mexico.

Multiple sclerosis is a chronic, autoimmune, degenerative disease. Therapies targeting B-cells have been shown to be effective in its treatment; however, there are few studies evaluating their efficacy in the Mexican population. To evaluate the clinical impact of rituximab in patients with newly-diagnosed relapsing-remitting multiple sclerosis (RRMS). Real life, descriptive study, in which rituximab was evaluated as treatment for RRMS over a 24-month period. Pre- and post-treatment clinical variables were analyzed; a comparison was made between treatment-naïve and non-treatment-naïve patients. Twenty-eight patients with RRMS were included. Mean age at diagnosis was 30.7 years, and 22 patients were treatment-naïve (78.5 %). After 24 months, there was a mean reduction of 1.8 points in the EDSS scale and a decrease in the number of active lesions on magnetic resonance imaging; a significant difference in both variables could be established (p < 0.05). However, the logistic regression model did not show a relationship between the variables for achieving NEDA-3 criteria. No serious adverse events were observed. Treatment with rituximab resulted in significant clinical and radiological improvement in treatment-naïve and non-treatment-naïve Mexican patients with RRMS.

AML-137 Real-Life Experience of Mexican Patients Treated With FLAG-VIDA Regimen in Relapsed/Refractory Acute Myeloid Leukemia (AML) and Next Generation Sequencing (NGS) Analysis of the Cases

AML-137 Real-Life Experience of Mexican Patients Treated With FLAG-VIDA Regimen in Relapsed/Refractory Acute Myeloid Leukemia (AML) and Next Generation Sequencing (NGS) Analysis of the Cases

248. SYSTEMIC INFLAMMATORY MARKERS AS PROGNOSTIC FACTORS IN ESOPHAGEAL CANCER: A MEXICAN PERSPECTIVE

Abstract Background Esophageal cancer (EC) represents the eighth most commonly diagnosed cancer, and sixth cause of cancer-related deaths worldwide. Several studies have demonstrated an association between systemic inflammation, anti-cancer immunity, and poor oncological outcomes in patients with EC. Biomarkers including neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) may reflect the balance between pro-cancer inflammation and anti-cancer immune response and have prognostic implications in Mexican esophageal cancer patients. Methods A retrospective review of a prospectively collected database of all EC patients from 2011–2022 was performed. Baseline pre-treatment NLR, LMR and PLR was collected. The date of last follow-up or death was ascertained from medical records. ROC curves were used to calculate cut-off values for NLR and PLR, while the median-value was used for LMR. Serum albumin of &amp;lt;3.5 g/dL was considered malnutrition. Kaplan–Meier (univariate) and Cox regression (multivariate) were performed to evaluate survival against prognostic factors. Results 498 patients were included during the study period, 80.1% men and 19.9% women, median age 60 (±12.2) years old. Adenocarcinoma (49.8%) was the most common histological subtype, followed by squamous cell carcinoma (31.7%). Clinical stage included: I (3%), IIA-B (11.8%), III (37.6%), IVA (2.6%), and IVB (44.2%). Neoadjuvant chemoradiotherapy was the predominant initial therapy (50.4%), followed by chemotherapy (41.7%). ROC curves revealed the following cut-off value: 2.92 for NLR, 174 for IPL, and 3.5 for LMR. In the univariate analysis, four prognostic factors were significant for overall survival (NLR, PLR, LMR, albumin) (Table 1), while in the multivariate analysis only NLR and albumin remained independent factors for survival (Table 2). Conclusion In our population, low NLR and high albumin can be considered independent prognostic markers in patients with esophageal cancer. These common pretreatment biomarkers can serve to identify patients with good prognostic factors, contributing to an improved consent process and therapeutic decision making. Further research should focus on more accurate cut-off values for survival prognostication.

Use of Ensemble Learning to Improve Performance of Known Convolutional Neural Networks for Mammography Classification

Convolutional neural networks and deep learning models represent the gold standard in medical image classification. Their innovative architectures have led to notable breakthroughs in image classification and feature extraction performance. However, these advancements often remain underutilized in the medical imaging field due to the scarcity of sufficient labeled data which are needed to leverage these new features fully. While many methodologies exhibit stellar performance on benchmark data sets like DDSM or Minimias, their efficacy drastically decreases when applied to real-world data sets. This study aims to develop a tool to streamline mammogram classification that maintains high reliability across different data sources. We use images from the DDSM data set and a proprietary data set, YERAL, which comprises 943 mammograms from Mexican patients. We evaluate the performance of ensemble learning algorithms combined with prevalent deep learning models such as Alexnet, VGG-16, and Inception. The computational results demonstrate the effectiveness of the proposed methodology, with models achieving 82% accuracy without overtaxing our hardware capabilities, and they also highlight the efficiency of ensemble algorithms in enhancing accuracy across all test cases.

Longitudinal clinical phenotyping of post COVID condition in Mexican adults recovering from severe COVID-19: a prospective cohort study.

Few studies have evaluated the presence of Post COVID-19 conditions (PCC) in people from Latin America, a region that has been heavily afflicted by the COVID-19 pandemic. In this study, we describe the frequency, co-occurrence, predictors, and duration of 23 symptoms in a cohort of Mexican patients with PCC. We prospectively enrolled and followed adult patients hospitalized for severe COVID-19 at a tertiary care centre in Mexico City. The incidence of PCC symptoms was determined using questionnaires. Unsupervised clustering of PCC symptom co-occurrence and Kaplan-Meier analyses of symptom persistence were performed. The effect of baseline clinical characteristics was evaluated using Cox regression models and reported with hazard ratios (HR). We found that amongst 192 patients with PCC, respiratory problems were the most prevalent and commonly co-occurred with functional activity impairment. 56% had ≥5 persistent symptoms. Symptom persistence probability at 360 days 0.78. Prior SARS-CoV-2 vaccination and infection during the Delta variant wave were associated with a shorter duration of PCC. Male sex was associated with a shorter duration of functional activity impairment and respiratory symptoms. Hypertension and diabetes were associated with a longer duration of functional impairment. Previous vaccination accelerated PCC recovery. In our cohort, PCC symptoms were frequent (particularly respiratory and neurocognitive ones) and persistent. Importantly, prior SARS-CoV-2 vaccination resulted in a shorter duration of PCC.

Prevalence and clinical correlations of Non-Motor Symptoms in patients with Ataxia: Study in a cohort of Mexican patients

Prevalence and clinical correlations of Non-Motor Symptoms in patients with Ataxia: Study in a cohort of Mexican patients