[Seroprevalence of anti-SARS-CoV-2 IgG antibodies in resident physicians]. / Seroprevalencia de anticuerpos IgG anti-SARS-CoV-2 en médicos residentes.

Background: COVID-19 pandemic spread around the world swiftly; there are several diagnostic strategies available. Health workers, especially medical residents (MR), are a high-risk population for acquiring this infection. Objective: To estimate the seroprevalence of antibodies against SARS-CoV-2 and the associated factors in MR of a third level hospital. Material and methods: 330 MR from different specialties were evaluated with a questionnaire and collection of blood samples for analysis by microparticle chemiluminescent immunoassay. The prevalence of previous infection was defined by seropositivity of these antibodies. Descriptive statistics and concordance between the RT-PCR tests and the presence of anti-SARS-CoV-2 IgG were used. Results: Of 330 MR, 84.5% actively participated in COVID patient care. One out of 3 reported symptoms of COVID-19; in 67.6% the possible site of infection was a hospital setting not associated with the COVID area. Out of 71 symptomatic subjects, 61.9% underwent RT-PCR against SARS-CoV-2; 20 were positive. In 15.8% of the total, the presence of anti-SARS-CoV-2 IgG antibodies was determined. Only 1 out of 3 subjects with a positive PCR had antibodies, and 11.3% of the cases, even with a positive RT-PCR test, did not develop humoral immunity. Conclusions: The seroprevalence was lower than that reported at the national level, potentially due to protection measures. The main risk factor was contact with the virus in areas of the hospital not related to COVID, making it imperative to reinforce security protocols in those spaces.

Introducción: la pandemia por COVID-19 se extendió rápidamente a nivel mundial; hay disponibles varias estrategias de diagnóstico. Los trabajadores de la salud, en especial los médicos residentes (MR), son una población de alto riesgo para adquirir dicha infección. Objetivo: estimar la seroprevalencia de anticuerpos contra el SARS-CoV-2 y los factores asociados en los MR de un hospital de tercer nivel. Material y métodos: se evaluaron 330 MR de diferentes especialidades con un cuestionario y recolección de muestras de sangre para análisis mediante un inmunoensayo quimioluminiscente de micropartículas. La prevalencia de infección previa se definió por seropositividad de estos anticuerpos. Se utilizó estadística descriptiva y concordancia entre las pruebas RT-PCR y presencia de IgG anti-SARS-CoV-2. Resultados: de los 330 MR, 84.5% participó activamente en atención de pacientes COVID. Uno de cada tres refirió síntomas de COVID-19; 67.6% tuvo posible sitio de contagio en ámbito hospitalario no asociado a Área COVID. De los 71 sujetos sintomáticos, 61.9% se realizaron RT-PCR; 20 fueron positivas. En 15.8% del total se determinó la presencia de anticuerpos IgG anti-SARS-CoV-2. Solo uno de cada tres sujetos con PCR positiva presentó anticuerpos y 11.3% de los casos, aun con RT-PCR positiva, no desarrolló inmunidad humoral. Conclusiones: la seroprevalencia fue menor que la reportada a nivel nacional, potencialmente por medidas de protección. El principal factor de riesgo fue el contacto con el virus en áreas del hospital no relacionadas a COVID, por lo que es imperativo reforzar los protocolos de seguridad en esos espacios.

Differences in mortality rate among patients hospitalized with severe COVID-19 according to their body mass index.

Background: Obesity has been described as a risk factor for COVID-19 severity and mortality. Previous studies report a linear association between BMI and adverse outcomes, meanwhile in other critical illness, excessive fat tissue is related to improved survival. Whether different BMI is related with the survival of patients with severe COVID-19 deserves further analysis. Objective: To determine the mortality rate among hospitalized patients with severe COVID-19 stratified according to BMI. Methods: The clinical files of all patients hospitalized from March to December 2020 with a positive PCR test for SARS-CoV-2 discharged due to improvement or death, were analyzed. A mixed effects logistic regression was carried out to determine which clinical and biochemical characteristics and comorbidities were associated with in-hospital mortality. Results: The cohort consisted of 608 patients with a median age of 59 years (interquartile ranges, IQR 46-69 years), median BMI of 28.7 kg/m2 (IQR 25.4-32.4 kg/m2), 65.5% were male. In-hospital mortality rate was 43.4%. Of the cohort 0.8% had low weight, 20.9% normal weight, 36.0% overweight, 26.5% obesity grade I, 10.2% obesity grade II and 5.6% obesity grade III. Mortality rate was highest in patients with low weight (80%), followed by patients with obesity grade III (58.8%) and grade II (50.0%). Overweight and underweight/obesity grade III were associated with higher mortality (OR of 9.75 [1.01-1.10] and OR 4.08 [1.64-10.14]), after adjusting by sex and age. Conclusions: The patients in the underweight/overweight and grade 3 obesity categories are at higher risk of COVID-19 related mortality, compared to those with grade I or II obesity.

Asociación de los índices neutrófilo/linfocito y linfocito/proteína C reactiva con mortalidad por COVID-19 / Association of neutrophil-to-lymphocyte and lymphocyte-to-C-reactive protein ratios with COVID-19-related mortality

Resumen Introducción: Los índices neutrófilo/linfocito (INL) y linfocito/proteína C reactiva (ILR) se usan para predecir severidad y mortalidad en diversas infecciones. Objetivo: Establecer en México el mejor punto de corte de INL e ILR para predecir la mortalidad en pacientes hospitalizados por COVID-19. Método: Estudio transversal analítico de pacientes hospitalizados por COVID-19 grave en un hospital de especialidades. Resultados: Falleció 34 % de 242 pacientes analizados. Los sujetos fallecidos tenían mayor edad (62 versus 51 años, p < 0.001), mayor prevalencia de hipertensión arterial sistémica > 10 años (59.4 versus 45.1 %, p = 0.022), así como INL más alto (17.66 versus 8.31, p < 0.001) e ILR más bajo (0.03 versus 0.06, p < 0.002) respecto a quienes sobrevivieron. Los puntos de corte para predecir mortalidad fueron INL > 12 e ILR < 0.03. La combinación de INL e ILR tuvo sensibilidad de 80 %, especificidad de 74 %, valor predictivo positivo de 46.15 %, valor predictivo negativo de 93.02 % y razón de momios de 11.429 para predecir la mortalidad. Conclusión: INL > 12 e ILR < 0.03 son biomarcadores útiles para evaluar el riesgo de mortalidad en pacientes mexicanos con COVID-19 grave.

Abstract Introduction: Neutrophil-to-lymphocyte (NLR) and lymphocyte-to-C-reactive protein (LCR) ratios are used to predict severity and mortality in various infections. Objective: To establish the best NLR and LCR cutoff point to predict mortality in patients hospitalized for COVID-19 in Mexico. Method: Analytical cross-sectional study of patients hospitalized for severe COVID-19 in a specialty hospital. Results: Out of 242 analyzed patients, 34 % died. The deceased subjects were older (62 vs. 51 years; p < 0.001), had a higher prevalence of > 10 years with systemic arterial hypertension (59.4 vs. 45.1 %, p = 0.022), as well as a higher NLR (17.66 vs. 8.31, p < 0.001) and lower LCR (0.03 vs. 0.06, p < 0.002] with regard to those who survived. The cutoff points to predict mortality were NLR > 12 and LCR < 0.03. The combination of NLR/LCR had a sensitivity of 80 %, specificity of 74 %, positive predictive value of 46.15 %, negative predictive value of 93.02 % and an odds ratio of 11.429 to predict mortality. Conclusion: NLR > 12 and LCR < 0.03 are useful biomarkers to evaluate the risk of mortality in Mexican patients with severe COVID- 19.

The low-harm score for predicting mortality in patients diagnosed with COVID-19: A multicentric validation study.

Objective: We sought to determine the accuracy of the LOW-HARM score (Lymphopenia, Oxygen saturation, White blood cells, Hypertension, Age, Renal injury, and Myocardial injury) for predicting death from coronavirus disease 2019) COVID-19. Methods: We derived the score as a concatenated Fagan's nomogram for Bayes theorem using data from published cohorts of patients with COVID-19. We validated the score on 400 consecutive COVID-19 hospital admissions (200 deaths and 200 survivors) from 12 hospitals in Mexico. We determined the sensitivity, specificity, and predictive values of LOW-HARM for predicting hospital death. Results: LOW-HARM scores and their distributions were significantly lower in patients who were discharged compared to those who died during their hospitalization 5 (SD: 14) versus 70 (SD: 28). The overall area under the curve for the LOW-HARM score was 0.96, (95% confidence interval: 0.94-0.98). A cutoff > 65 points had a specificity of 97.5% and a positive predictive value of 96%. Conclusions: The LOW-HARM score measured at hospital admission is highly specific and clinically useful for predicting mortality in patients with COVID-19.

Case Report: Rhabdomyolysis in a Patient with COVID-19: A Proposed Diagnostic-Therapeutic Algorithm.

COVID-19 represents the greatest health challenge of modern years. The spectrum of illness comprises respiratory and non-respiratory manifestations. We report the case of an adult man with COVID-19 who presented with rhabdomyolysis as a principal extrapulmonary manifestation. Our patient presented with dyspnea, fever, and muscle pain. After a comprehensive approach, the diagnosis of COVID-19 and rhabdomyolysis was made. He developed acute kidney injury requiring renal replacement therapy without reversibility, despite optimal treatment. We performed a literature search for similar cases, discuss the potential mechanisms implied, and propose a diagnostic-therapeutic algorithm.

Association of neutrophil-to-lymphocyte and lymphocyte-to-C-reactive protein ratios with COVID-19-related mortality.

INTRODUCTION: Neutrophil-to-lymphocyte (NLR) and lymphocyte-to-C-reactive protein (LCR) ratios are used to predict severity and mortality in various infections. OBJECTIVE: To establish the best NLR and LCR cutoff point to predict mortality in patients hospitalized for COVID-19 in Mexico. METHOD: Analytical cross-sectional study of patients hospitalized for severe COVID-19 in a specialty hospital. RESULTS: Out of 242 analyzed patients, 34 % died. The deceased subjects were older (62 vs. 51 years; p < 0.001), had a higher prevalence of > 10 years with systemic arterial hypertension (59.4 vs. 45.1 %, p = 0.022), as well as a higher NLR (17.66 vs. 8.31, p < 0.001) and lower LCR (0.03 vs. 0.06, p < 0.002) with regard to those who survived. The cutoff points to predict mortality were NLR > 12 and LCR < 0.03. The combination of NLR/LCR had a sensitivity of 80 %, specificity of 74 %, positive predictive value of 46.15 %, negative predictive value of 93.02 % and an odds ratio of 11.429 to predict mortality. CONCLUSION: NLR > 12 and LCR < 0.03 are useful biomarkers to evaluate the risk of mortality in Mexican patients with severe COVID- 19. INTRODUCCIÓN: Los índices neutrófilo/linfocito (INL) y linfocito/proteína C reactiva (ILR) se usan para predecir severidad y mortalidad en diversas infecciones. OBJETIVO: Establecer en México el mejor punto de corte de INL e ILR para predecir la mortalidad en pacientes hospitalizados por COVID-19. MÉTODO: Estudio transversal analítico de pacientes hospitalizados por COVID-19 grave en un hospital de especialidades. RESULTADOS: Falleció 34 % de 242 pacientes analizados. Los sujetos fallecidos tenían mayor edad (62 versus 51 años, p < 0.001), mayor prevalencia de hipertensión arterial sistémica > 10 años (59.4 versus 45.1 %, p = 0.022), así como INL más alto (17.66 versus 8.31, p < 0.001) e ILR más bajo (0.03 versus 0.06, p < 0.002) respecto a quienes sobrevivieron. Los puntos de corte para predecir mortalidad fueron INL > 12 e ILR < 0.03. La combinación de INL e ILR tuvo sensibilidad de 80 %, especificidad de 74 %, valor predictivo positivo de 46.15 %, valor predictivo negativo de 93.02 % y razón de momios de 11.429 para predecir la mortalidad. CONCLUSIÓN: INL > 12 e ILR < 0.03 son biomarcadores útiles para evaluar el riesgo de mortalidad en pacientes mexicanos con COVID-19 grave.

[Adult-onset Still's disease and the neutrophil-lymphocyte index in the Mexican population. A case series report]. / Enfermedad de Still del adulto y el índice neutrófilo/linfocito en población mexicana. Reporte de serie de casos.

BACKGROUND: In Mexico, adult-onset Still's disease (AOSD) is one of the causes of fever of unknown origin (FUO). The aim of this study is to describe a series of AOSD cases from a FUO cohort in order to know the clinical and biochemical characteristics of the cases, as well as to describe the neutrophil-lymphocyte index (NLI), which is a clinical marker of inflammation in autoimmune diseases. CASE REPORT: An observational study of 24 cases with AOSD; 72 % of them were women, the median age was 43 years (IQR 37.7-59.7), and the most frequent manifestations were classic rash (84 %) and arthralgia (100 %). All of them had tested negative for rheumatoid factor, antinuclear antibodies, and hyperferritinemia; 83 % had NLI > 3.08. The most used treatment was the combination of methotrexate with corticosteroids; seven patients required biological therapy, and one of them presented a hypersensitivity reaction. CONCLUSION: When there's FUO, the existence of AOSD should be suspected; also in the presence of rash, arthralgia, hyperferritinemia, and NLI > 3.08.

Antecedentes: En México, la enfermedad de Still del adulto (ESA) es una causa de fiebre de origen desconocido (FOD). El objetivo de este informe fue describir una serie de casos de ESA de una cohorte de FOD para conocer las características clínicas y bioquímicas, así como describir el índice neutrófilo/linfocito (INL), marcador clínico de inflamación en enfermedades autoinmunes. Caso clínico: Estudio observacional de 24 casos con ESA; 72 % fue del sexo femenino, la edad fue de 43 años (37.7-59.7) y las manifestaciones más frecuentes fueron rash clásico (84 %) y artralgias (100 %). Todos tuvieron factor reumatoide, anticuerpos antinucleares negativos e hiperferritinemia; 83 % tuvo INL > 3.08. El tratamiento más empleado fue la combinación de metotrexato y corticosteroides; siete pacientes ameritaron terapia biológica, uno presentó reacción de hipersensibilidad. Conclusión: Ante fiebre de origen desconocido, debe sospecharse ESA si, además, existe rash, artralgias, hiperferritinemia e INL > 3.08.

Genetic Polymorphisms Associated with Thrombotic Disease Comparison of Two Territories: Myocardial Infarction and Ischemic Stroke.

BACKGROUND AND PURPOSE: The thrombin-activatable fibrinolysis inhibitor (TAFI) is an important inhibitor of fibrinolysis and plays a critical role in the pathogenesis of arterial thrombosis; genetic polymorphisms of the TAFI gene affect its activity and increase the risk of thrombosis. Moreover, studies in young patients are still scarce. The aim was to examine the contribution of the Thr325Ile and Ala147Thr polymorphisms with ST acute myocardial infarction (STEMI) or idiopathic ischemic stroke (IIS) in the young Mexican population. METHODS: A total of 244 patients with STEMI ≤45 years of age and 244 controls. In a second study, 250 patients with IIS ≤45 years of age were recruited, including 250 controls. In both studies, cases and controls were matched by age and sex. The polymorphisms were determined in all participants by PCR-RFLP. RESULTS: There was significant difference in the Thr325Ile genotype distribution (P = 0.001) and allele frequency (P = 0.001) between STEMI and control groups, but no difference in the Ala147Thr genotype distribution (P = 0.24) and allele frequency (P = 0.46), neither in the Thr325Ile genotype distribution (P = 0.25) nor in the Ala147Thr genotype distribution (P = 0.46) or their allele frequencies; there was significant difference between IIS and the control group. There were independent factors for STEMI: the Ile allele (P = 0.01), type 2 diabetes mellitus (P = 0.001), hypertension (P = 0.001), smoking (P = 0.001), dyslipidemia (P = 0.001), and family history of atherothrombotic disease (P = 0.001). The independent factors for IIS were hypertension (P = 0.001), smoking (P < 0.01), and family history of atherothrombotic disease (P < 0.01). CONCLUSIONS: The Thr325Ile polymorphism, but no Ala147Thr polymorphism, represents an independent risk factor for STEMI in the young Mexican population.