Association of leptin with cardiometabolic factors in schoolchildren and adolescents with congenital adrenal hyperplasia. / Asociación de leptina con factores cardiometabólicos en escolares y adolescentes con hiperplasia suprarrenal congénita.

Introduction: In congenital adrenal hyperplasia (CAH), obesity, hyperinsulinemia and leptin levels are increased. Objective: To identify the frequency of cardiometabolic risk factors (CRF) in children and adolescents with CAH and to explore the relationship with leptin levels. Method: Cross-sectional study of 40 patients who underwent anthropometric measurements and had fasting glucose, insulin, triglycerides, 17-hidroxyprogesterone, leptin, HDL and LDL-cholesterol assessed. The patients were classified according to the number of CRFs, and leptin levels were analyzed with the Kruskal-Wallis test. Pearson's correlation was applied between leptin, body mass index (BMI) z-score and body fat percentage. Results: Fifty percent of the patients had obesity and overweight, 59% had hypertriglyceridemia, 40%, hypoalphalipoproteinemia, 27.5%, high LDL-cholesterol and 22.5% insulin resistance. There was positive correlation between leptin and body fat percentage (r = 0.64), BMI z-score (r = 0.55) and the number of CRFs (r = 0.65). In the obesity-adjusted multivariate analysis, leptin levels were associated with the number of CRFs. Conclusion: CAH had a high frequency of CRFs and leptin appeared to be associated with a more adverse cardiometabolic profile in subjects with obesity and overweight.

Introducción: En la hiperplasia suprarrenal congénita (HSC), la obesidad, la hiperinsulinemia y los niveles de leptina se encuentran incrementados. Objetivo: Identificar la frecuencia de los factores de riesgo cardiometabólico (FRC) en niños y adolescentes con HSC y explorar la relación con los niveles de leptina. Método: Estudio transversal de 40 pacientes a quienes se realizó somatometría y evaluación de glucosa, insulina, triglicéridos, 17-hidroxiprogesterona, leptina, colesterol HDL y LDL en ayuno. Los pacientes fueron clasificados por el número de FRC y se analizaron los niveles de leptina con Kruskal-Wallis. Se aplicó correlación de Pearson entre la leptina, puntuación Z del índice de masa corporal (zIMC) y porcentaje de grasa corporal. Resultados: 50 % de los pacientes presentó obesidad y sobrepeso, 59 % hipertrigliceridemia, 40 % hipoalfalipoproteinemia, 27.5 % colesterol LDL alto y 22.5 % resistencia a la insulina. Hubo correlación positiva entre leptina y porcentaje de grasa corporal (r = 0.64), el zIMC (r = 0.55) y el número de FRC (r = 0.65). En el análisis multivariado ajustado por obesidad, los niveles de leptina se asociaron con el número de FRC. Conclusión: La HSC tuvo alta frecuencia de FRC y al parecer la leptina se asoció con perfil cardiometabólico más adverso en sujetos con obesidad y sobrepeso.

Children's perception on obesity and quality of life: a Mexican survey.

BACKGROUND: Child obesity has become a major health problem worldwide. In order to design successful intervention strategies, it is necessary to understand how children perceive obesity and its consequences. METHODS: With the aim to evaluate scholar children perception of obesity as a significant factor on the quality of life, we developed and validated the "Obesity impact on the quality of life perception-questionnaire" (ObI-Q). We surveyed 1335 healthy children aged 6-12 years, randomly selected from elementary schools in Mexico City. The ObI-Q comprises eight multiple-choice items that explore aspects related to the quality of life during adult life; such as health, life span, emotional status, lifestyle, social recognition and economic status. In order to identify perceptional modifier factors, results were analyzed through multivariable logistic regression. Variables included gender, age, and child nutritional status, as well as the child's perception of parental nutritional status. RESULTS: ObI-Q results showed that most children (64.71%) considered obesity as a negative condition that influences health and social performance. This perception was inversely related to age (OR = 0.64, p = 0.003), as well as to the perception of their mother nutritional status (OR = 0.47, p = 0.01). CONCLUSIONS: This study provides an overview of children's perception on obesity and its consequences. Because the high proportion of schoolchildren who do not view obesity as an adverse consequence to the quality of life, then the results of this study could be used as part of strategies for the prevention of overweight and obesity.

Global Prevalence and Severity of Retinopathy of Prematurity over the Last Four Decades (1985-2021): A Systematic Review and Meta-Analysis.

BACKGROUND: Retinopathy of prematurity (ROP) is a vasoproliferative disease of the retina that occurs in premature infants. The prevalence of ROP reported so far is inconsistent. AIM: To conduct a systematic review to describe the trend of ROP prevalence between 1985 and 2021, and to determine the influence of countries' economic conditions on ROP prevalence. METHODS: We searched PubMed, Embase, and Google Scholar for studies published between January 1985 and December 2021 using the following MeSH terms: "retinopathy of prematurity", "ROP", "incidence", and "prevalence". Two independent reviewers examined the articles to select studies that met the selection criteria and performed data extraction and study quality assessment. For the meta-analysis, the pooled prevalence was calculated using a random-effects model and R software. RESULTS: Of 5,250 titles and abstracts, 139 original studies met the inclusion criteria; a total of 121,618 premature infants were included in these studies. The pooled prevalence of ROP was 31.9% (95% confidence interval [CI] 29.0-34.8) and that of severe ROP was 7.5% (6.5-8.7). In general, no significant differences in prevalence were found over the four decades; however, we found a higher prevalence in premature infants ≤28 weeks of gestational age. In addition, the highest ROP prevalence was found in lower-middle-income countries with high mortality rates. In contrast, the highest severe ROP prevalence was found in high-income countries. CONCLUSION: ROP remains a common cause of morbidity in premature infants worldwide. Therefore, it seems necessary to maintain early identification strategies for patients at higher risk, particularly in low- and middle-income countries.

[Comparison of serum uric acid and liver enzyme levels in adolescents with obesity and with metabolic syndrome]. / Comparación de los niveles séricos de ácido úrico y enzimas hepáticas entre adolescentes con obesidad y con síndrome metabólico.

INTRODUCTION: a relationship has been observed between elevated levels of liver enzymes and uric acid with the presence of metabolic syndrome (MS) in the pediatric population. OBJECTIVE: to compare serum liver enzyme and uric acid levels between adolescents with and without MS. METHODS: a cross-sectional study was carried out in adolescents with obesity between 10 and 18 years old. Somatometric data, serum insulin, lipid profile, uric acid levels and liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT] and gamma-glutamyl transferase [GGT]) were analyzed. STATISTICAL ANALYSIS: Student's t test or the Chi-square test was used to evaluate differences between groups. RESULTS: a total of 1095 adolescents with obesity were included (444 with MS and 651 without MS). The group with MS had a higher BMI (with MS 2.28 vs without MS 2.11 p < 0.001), with no difference in body fat (42.9 % vs 42.9 %, p = 0.978). The MS group had significantly higher levels of AST (34.4 vs. 29.5, p = 0.013), ALT (42.2 vs. 34.6, p = 0.003), and uric acid (6.17 vs. 5.74, p = 0.002). comparison to the group without MS. The proportion of ALT (40.5 % vs 29.5 %, p = 0.029) and altered uric acid (58.1 % vs. 45.6 %, p = 0.019) was higher in the MS group. CONCLUSIONS: serum levels of ALT, AST and uric acid in adolescents with obesity and MS were higher compared to those without MS. Altered ALT was a risk factor for SM.

PD-L1 expression induced by the 2009 pandemic influenza A(H1N1) virus impairs the human T cell response.

PD-L1 expression plays a critical role in the impairment of T cell responses during chronic infections; however, the expression of PD-L1 on T cells during acute viral infections, particularly during the pandemic influenza virus (A(H1N1)pdm09), and its effects on the T cell response have not been widely explored. We found that A(H1N1)pdm09 virus induced PD-L1 expression on human dendritic cells (DCs) and T cells, as well as PD-1 expression on T cells. PD-L1 expression impaired the T cell response against A(H1N1)pdm09 by promoting CD8⁺ T cell death and reducing cytokine production. Furthermore, we found increased PD-L1 expression on DCs and T cells from influenza-infected patients from the first and second 2009 pandemic waves in Mexico City. PD-L1 expression on CD8⁺ T cells correlated inversely with T cell proportions in patients infected with A(H1N1)pdm09. Therefore, PD-L1 expression on DCs and T cells could be associated with an impaired T cell response during acute infection with A(H1N1)pdm09 virus.

[Aswer to "Comment on article "Bibliometric analysis of scientific publications on COVID-19 elaborated by staff of the Instituto Mexicano del Seguro Social""]. / Respuesta a "Comentario al artículo "Análisis bibliométrico de las publicaciones científicas sobre COVID-19 realizadas por personal IMSS"".

We thank the group headed by Jorge Valencia Alonso for taking the time to review in detail and prepare the letter about our article entitled: " Bibliometric analysis of scientific publications on COVID-19 elaborated by staff of the Instituto Mexicano del Seguro Social", which has recently been published in the Medical Journal of the Mexican Social Security Institute. Based on your observations and comments, we allow ourselves to make the following clarifications following the same sequence of your letter to the Editor.

Agradecemos al grupo encabezado por Jorge Valencia Alonso por tomarse el tiempo para revisar con detalle y elaborar la carta sobre nuestro artículo titulado: "Análisis bibliométrico de las publicaciones científicas sobre COVID-19 por personal del IMSS", que recientemente se ha publicado en la Revista Médica del Instituto Mexicano del Seguro Social. De acuerdo con sus observaciones y comentarios, nos permitimos realizar las siguientes aclaraciones siguiendo la misma secuencia de su carta al Editor.

Leptin/adiponectin ratio as a prognostic factor for increased weight gain in girls with central precocious puberty.

Objective: To determine if the leptin, adiponectin, and leptin/adiponectin ratio (LAR) can predict weight gain at the end of GnRH analogs (GnRHa) treatment in girls with central precocious puberty (CPP). Material and methods: Study design: prospective cohort. Serum levels of leptin and adiponectin were determined at diagnosis of CPP. Anthropometry was performed at diagnosis of CPP and every six-months, until treatment with GnRHa was discontinued and they presented menarche. Patients were divided according to BMI<94 and BMI>95 percentile at diagnosis of CPP. The outcome was the increased in weight gain (e.g., from normal weight to overweight) at the end of follow-up. Statistical analysis: repeated measures ANOVA test and Student's t-test were used to compare groups. Logistic regression analysis was used to evaluate the association of leptin and adiponectin levels, as well as LAR values with increased weight gain. Results: Fifty-six CPP patients were studied, 18 had BMI >95 percentile and 38 BMI <94 percentile. Of the 18 patients who initially had BMI >95th, two patients went from obesity to overweight, while among the 38 patients who started with BMI <94th, 21 (55.2%) increased their weight gain at the end of follow-up. This last group had higher leptin levels (8.99 ± 0.6 vs 6.14 ± 0.8, p=0.005) and higher LAR values compared to those who remained in the same weight (1.3 ± 0.5 vs 0.96 ± 0.56, p=0.01). In the logistic regression analysis, it was found that higher leptin levels and higher LAR values were associated with increased weight gain (RR 1.31, 95%CI 1.03-1.66, RR 4.86, 95%CI 1.10-21.51, respectively), regardless of birth weight, pubertal stage, age, and bone/chronological age ratio. Conclusions: In patients with CPP, leptin levels and higher LAR values appear to be associated with significantly greater weight gain during GhRHa treatment, particularly in girls starting with BMI < 94 percentile.

Adipokines as predictive factor of cardiac function in pediatric patients with chronic kidney disease.

Background: Adipokines are associated with cardiovascular disease; in chronic kidney disease (CKD) patients adipokines could be useful prognostic factors. Objectives: To explore whether leptin and adiponectin in kidney replacement therapy (KRT) children could have a role on their cardiac function, in the long-term. Design: Prospective cohort study was performed with pediatric KRT patients, aged 8 to 17 years who were undergoing hemodialysis or peritoneal dialysis. At enrollment, lipid profile, adipokines (leptin, leptin receptor, free leptin, and adiponectin), anthropometric measurements and cardiological evaluation were determined. At two-year follow-up, a new cardiological evaluation was performed. Statistical analysis: Quantitative data are presented as median and interquartile range (IQR). Mann-Whitney U test and Chi-squared were used for the between-group comparison. Multivariate analyzes were performed to determine the association of adipokines levels with ventricular ejection fraction (LEVF). Results: We included 56 patients, with a median age of 12.5 years. In the first cardiological evaluation, median LVEF was 70.0% (IQR 61%, 76%), 20 patients (35.7%) had some cardiovascular condition, and 10 (17.8%) altered LVEF. At 24-month follow-up, the median LVEF was 70.5% (IQR 65.1%, 77%), while the delta-LVEF values was 3% (IQR -6.5%, 7%). Delta-LVEF were correlated with baseline adipokines serum levels, and the only positive correlation found was with free leptin (r=0.303, p=0.025). In multivariate analysis, levels of free leptin (Coef. 0.12, p<0.036) and leptin (coef. 1.72, p=0.049), as well as baseline LVEF (Coef. -0.65, p<0.001) were associated with delta-LVEF. Conclusions: Free leptin, leptin and LVEF at the beginning of follow-up were associated with the LVEF decrease at the 24-month follow-up in KRT children.

[Correlation of uric acid with carotid intima media thickness in obese adolescents]. / Correlación del ácido úrico con el grosor de la íntima media de la carótida en adolescentes con obesidad.

Introduction: Introduction: obesity in the pediatric population is a public health problem. The correlation of uric acid and carotid intima media thickness in adults has been demonstrated. Objective: to identify the correlation of uric acid and carotid intima media thickness in adolescents with obesity. Material and methods: an observational, cross-sectional study was carried out. Patients aged ten to 16 years with a diagnosis of obesity were included. Uric acid, lipid profile and carotid intima media thickness were determined. In relation to the statistical analysis, carotid intima media thickness was correlated with uric acid levels through Spearman's correlation coefficient. Results: one hundred and sixty-nine adolescents were included with a median age of 13 years, without predominance of sex. A positive correlation of uric acid with carotid intima media thickness was identified (r = 0.242, p = 0.001). When stratified according to sex, there was no correlation in women (r = -0.187, p = 0.074), while in men it increased (r = 0.36, p = 0.001) and by pubertal stage, pubertal male adolescents had a positive correlation (p = 0.384, p = 0.002). Conclusion: a weak positive correlation was identified between carotid intimal thickness and uric acid in obese adolescents.

Introducción: Introducción: la obesidad en la población pediátrica es un problema de salud pública. Se ha demostrado la correlación del ácido úrico y el grosor de la íntima media de la carótida en adultos. Objetivo: identificar la correlación del ácido úrico y el grosor de la íntima media de la carótida en adolescentes con obesidad. Material y métodos: se realizó un estudio observacional, transversal. Se incluyeron pacientes de diez a 16 años con diagnóstico de obesidad. Se determinó ácido úrico, perfil de lípidos y grosor de la íntima media carotidea. En el análisis estadístico, se correlacionó el grosor de la íntima media carotídea con los niveles de ácido úrico a través del coeficiente de correlación de Spearman. Resultados: se incluyeron 169 adolescentes con una mediana para la edad de 13 años, sin predominio de sexo. Se identificó una correlación positiva del ácido úrico con el grosor de la íntima media carotídea (r = 0,242, p = 0,001). Al estratificarse de acuerdo con el sexo, no hubo correlación en las mujeres (r = -0,187, p = 0,074), mientras que en los hombres aumentó (r = 0,36, p = 0,001) y por estadio puberal, los adolescentes varones púberes tuvieron una correlación positiva (p = 0,384, p = 0,002). Conclusión: se identificó una correlación positiva débil entre el grosor de la íntima de la carótida y el ácido úrico en adolescentes con obesidad.

Vitamin D levels in the pre- and post-COVID-19 pandemic periods in pediatric patients with chronic kidney disease.

Introduction: Vitamin D (VD) deficiency is common in children with chronic kidney disease (CKD) because of multiple factors. During the coronavirus disease 2019 (COVID-19) pandemic, it increased because of medicine shortage and no enough medical service for patients with non-COVID-19 diseases. Objective: To analyze the effects of the COVID-19 pandemic-related lockdown on the serum levels and status of 25-hydroxyvitamin D3 (25-[OH]D) in children with CKD. Materials and methods: This retrospective study included patients (6-18 years old) who were diagnosed with CKD stage 2-5 and routinely measured for serum VD levels between May 2019 and December 2022. Serum 25-(OH)D levels were measured before, during, and after the pandemic (2019, 2020-2021, and 2022, respectively). The daily dose of cholecalciferol supplementation and the readjustment (if required) were recorded. Results: This study included 171 patients (median age: 12 years). Before the pandemic, the median serum VD level was 25.0 ng/mL (19.3% VD deficiency). Then, VD supplementation was adjusted to 400-1,200 UI daily in 98.8% (n = 169) of patients. During the pandemic, the median VD level decreased to 22.5 ng/mL (43.3% VD deficiency). Hence, the supplementation was readjusted, and after the pandemic, the level was 28.7 ng/mL (18.7% VD deficiency), indicating a statistically significant increase in serum VD levels from the prepandemic period (p = 0.007). Conclusion: Decreased serum VD levels and increased VD deficiency frequency were observed in patients with CKD during the COVID-19 but improved after readjustment of supplementation.

Characteristics and outcomes of multisystem inflammatory syndrome in children: A multicenter, retrospective, observational cohort study in Mexico.

Introduction: Multisystem inflammatory syndrome in children associated with coronavirus disease 2019 (MIS-C), a novel hyperinflammatory condition secondary to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, is associated with severe outcomes such as coronary artery aneurysm and death. Methods: This multicenter, retrospective, observational cohort study including eight centers in Mexico, aimed to describe the clinical characteristics and outcomes of patients with MIS-C. Patient data were evaluated using latent class analysis (LCA) to categorize patients into three phenotypes: toxic shock syndrome-like (TSSL)-MIS-C, Kawasaki disease-like (KDL)-MIS-C, and nonspecific MIS-C (NS-MIS-C). Risk factors for adverse outcomes were estimated using multilevel mixed-effects logistic regression. Results: The study included 239 patients with MIS-C, including 61 (26%), 70 (29%), and 108 (45%) patients in the TSSL-MIS-C, KDL-MIS-C, and NS-MIS-C groups, respectively. Fifty-four percent of the patients were admitted to the intensive care unit, and 42%, 78%, and 41% received intravenous immunoglobulin, systemic glucocorticoids, and anticoagulants, respectively. Coronary artery dilatation and aneurysms were found in 5.7% and 13.2% of the patients in whom coronary artery diameter was measured, respectively. Any cause in-hospital mortality was 5.4%. Hospitalization after ten days of symptoms was associated with coronary artery abnormalities (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.2-2.0). Age ≥10 years (OR: 5.6, 95% CI: 1.4-2.04), severe underlying condition (OR: 9.3, 95% CI: 2.8-31.0), platelet count <150,000 /mm3 (OR: 4.2, 95% CI: 1.2-14.7), international normalized ratio >1.2 (OR: 3.8, 95% CI: 1.05-13.9), and serum ferritin concentration >1,500 mg/dl at admission (OR: 52, 95% CI: 5.9-463) were risk factors for death. Discussion: Mortality in patients with MIS-C was higher than reported in other series, probably because of a high rate of cases with serious underlying diseases.

Association between carotid intima-media thickness, buccodental status, and glycemic control in pediatric type 1 diabetes.

OBJECTIVE: To evaluate the association between carotid intima-media thickness, buccodental status, and glycemic control in patients with type 1 diabetes. METHODS: Cross-sectional study with consecutive cases attended in an outpatient clinic (n = 69). Medical and clinical dental history, HbA1c, lipid profile, treatment period, and daily insulin dosage were recorded. Sociodemographic data and anthropometrical measurements were obtained by standardized questionnaire. Doppler real-time ultrasound was performed by a single experienced vascular radiologist blinded to the study. Assessment of buccodental status was done by the Maxillofacial Unit of the Pediatrics Hospital, and an oral scrape culture was collected. RESULTS: The mean age was 11.7 ± 3.0 years, with diabetes 5.1 ± 3.3 years. Mean HbA1c was 8.5 ± 1.7%. Primary teeth were present in 52.2% and bacterial plaque in 94.2%. Buccodental conditions featured caries (63.8%), gingivitis (84%), and enamel demineralization (26.1%): white spot lesions (18.8%) and cavitated lesions (7.3%). Bacteria associated with caries were found in 44.1%. Patients in the highest HbA1c tertile (>8.5%) had greater frequency of buccodental conditions and were positive for Streptococcus mutans and Candida albicans; also, cIMT increased and vessel compliance decreased compared to those in the lowest tertile (<7.0%) (p < 0.05). CONCLUSIONS: More buccodental conditions and carotid intima-media thickness increase appeared in the patients with HbA1c level > 8.5%, suggesting onset of atherosclerosis. The correlation between buccodental status and HbA1c values may indicate the connection between inflammatory states of atherosclerosis and type 1 diabetes.

Economic evaluation of the use of exogenous pulmonary surfactants in preterm newborns in a Mexican population.

OBJECTIVE: To estimate the cost-effectiveness ratio of surfactant rescue treatment of premature infants with respiratory distress syndrome (RDS) who are covered by the Medical Insurance for a New Generation. MATERIALS AND METHODS: A cost-effectiveness evaluation was conducted from the third-payer perspective. Comparisons were made between the use of bovine surfactant (BS) therapy and without BS therapy. A decision tree model with a lifetime horizon was used where the measurements of effectiveness were life years gained (LYG) and quality-adjusted life years (QALYs). A 5% discount rate was considered for costs and health outcomes. All costs are expressed in Mexican pesos 2009. RESULTS: Incremental cost-effectiveness ratios (ICER) were MXN$136,670 per LYG and MXN$125,250 per QALY. CONCLUSION: Surfactant therapy was confirmed as a cost-effective strategy in accordance with World Health Organization criteria of three per capita gross domestic product (GDP) per QALY in premature infants with RDS in Mexico.

COVID-19 in Neonates with Positive RT-PCR Test. Systematic Review.

BACKGROUND: COVID-19 is an infectious disease of variable severity caused by a new coronavirus. Clinical presentation ranges from asymptomatic cases to severe illness. Most cases in newborns appear to be asymptomatic or mild. OBJECTIVE: To conduct a systematic review of the literature on published studies of COVID-19 in newborns with a positive RT-PCR test. METHODS: The PubMed and EMBASE databases were searched for infection data in newborns from 1 December 2019-21 May 2021. The mesh terms included "SARS-CoV-2", "COVID-19", "novel coronavirus", "newborns" and "neonates". The selection criteria were as follows: original studies reporting clinical, radiological, laboratory, and outcome data in newborns with a positive RT-PCR test for SARS-CoV-2. Two independent investigators reviewed the studies. RESULTS: Seventy-two studies that involved 236 newborns were included. The main clinical manifestations were fever (43.2%), respiratory (46.6%), and gastrointestinal (35.2%) symptoms; 60.1% had mild/moderate disease. A total of 52.5% had a chest X-ray; 43.5% were normal, and 24.1% reported consolidation/infiltration images. The most frequent laboratory abnormalities were elevated C reactive protein and elevated procalcitonin and lymphopenia. Mortality was 1.7%. CONCLUSION: Symptoms of SARS-CoV-2 infection were mild to moderate in most of the newborns. The prognosis was good, and mortality was mainly associated with other comorbidities.

[Bibliometric analysis of scientific publications on COVID-19 elaborated by staff of the Instituto Mexicano del Seguro Social]. / Análisis bibliométrico de las publicaciones científicas sobre COVID-19 realizadas por personal IMSS.

Background: Since the beginning of the pandemic, new knowledge about COVID-19 obtained by research has been disseminated in medical and scientific journals, but the large number of publications that have been generated in such a short time has been impressive. Objective: To perform a bibliometric analysis of the published articles in medical-scientific journals carried-out by the Mexican Social Security Institute (IMSS) personnel on COVID-19. Material and methods: Systematic review of the literature, identifying the publications included in the PubMed and EMBASE databases, up to September 2022. Articles on COVID-19 were included, in which at least one author had IMSS affiliation; there was no restriction on the type of publication, so original articles, review articles, clinical case reports, etc. were included. The analysis was descriptive. Results: 588 abstracts were obtained, of which 533 full length articles met the selection criteria. Most were research articles (48%), followed by review articles. Mainly clinical or epidemiological aspects were addressed. They were published in 232 different journals, with a predominance of foreign journals (91.8%). Around half of the publications were carried out by IMSS personnel together with authors from other institutions, national or foreign. Conclusions: The scientific contributions prepared by IMSS personnel have contributed to understanding clinical, epidemiological and basic aspects of COVID-19, which has had an impact on improving the quality of care for its beneficiaries.

Introducción: desde el inicio de la pandemia los nuevos conocimientos sobre COVID-19 han sido difundidos en revistas médico-científicas, y ha sido impresionante la gran cantidad de publicaciones que se ha generado en tan poco tiempo. Objetivo: realizar un análisis bibliométrico de los artículos publicados en revistas médico-científicas elaborados por personal del Instituto Mexicano del Seguro Social (IMSS) sobre COVID-19. Material y métodos: revisión sistemática de la literatura, identificando las publicaciones incluidas en las bases de datos PubMed y EMBASE, hasta septiembre de 2022. Se incluyeron los artículos sobre COVID-19 en los que al menos un autor tuviera adscripción IMSS, sin restricción del tipo de publicación, por lo que se incluyeron artículos originales, de revisión, reportes de casos clínicos, etc. El análisis fue de tipo descriptivo. Resultados: se obtuvieron 588 resúmenes, de los cuales 533 artículos cumplieron con los criterios de selección. La mayoría correspondió a artículos de investigación y revisión. Principalmente se abordaron aspectos clínicos o epidemiológicos. Se publicaron en 232 revistas diferentes, predominando revistas extranjeras (91.8%). Alrededor de la mitad de las publicaciones fueron realizadas por personal del IMSS en conjunto con autores de otras instituciones, nacionales o extranjeras. Conclusiones: las aportaciones científicas elaboradas por personal del IMSS han contribuido a conocer aspectos clínicos, epidemiológicos y básicos sobre COVID-19, lo cual ha impactado en la mejora de la calidad de atención de sus derechohabientes.

[Usefulness of a nutritional strategy on dyslipidemia in pediatric patients with terminal chronic kidney disease]. / Utilidad de una estrategia nutricional sobre la dislipidemia en pacientes pediátricos con enfermedad renal crónica terminal.

Introduction: Background and objective: in chronic kidney disease (CKD) there are several factors that increase the presence of dyslipidemia. The aim of this study was to identify the usefulness of a nutritional intervention, in children with terminal CKD, on dyslipidemia 6 months after intervention start. Materials and methods: a quasi-experiment study (before and after) was performed. End-stage CKD patients on peritoneal dialysis and hemodialysis were included. Each child underwent a determination somatometry, and lipid profile at the beginning and at 6 months of follow-up. A nutritional guide was made with food traffic lights, turning the food that should be consumed in the least amount possible in red. In addition to including life-size food using educational models. To compare the quantitative variables before and after the intervention, the variables were transformed to their logarithm and a paired Student's t-test was applied. Results: a total of 41 patients were analyzed. After the intervention, the parameters in the lipid profile were modified; meanwhile HDL concentrations increased (41.0 mg/dL vs 44.4 mg/dL, p = 0.048), triglyceride concentrations decreased (227.1 mg/dL vs 185.9 mg/dL, p = 0.007), and these changes persist even after excluding patients who were under lipid-lowering treatment (195 mg/dL vs 171.6, p = 0.049). Regarding the state of dyslipidemia, hypertriglyceridemia decreased, without reaching significance (80.5 % vs 62.5 %, p = 0.073). Conclusions: the nutritional intervention improved HDL and triglyceride concentrations 6 months afterwards in children with terminal CKD.

Introducción: Antecedentes y objetivo: en la enfermedad renal crónica (ERC) existen múltiples factores que incrementan la presencia de la dislipidemia. El objetivo fue identificar la utilidad de una intervención nutricional sobre la dislipidemia, en niños con ERC terminal, a los 6 meses del inicio de la intervención. Materiales y métodos: estudio cuasiexperimental (antes y después). Se incluyeron pacientes con ERC terminal en diálisis peritoneal y hemodiálisis. A cada niño se le realizaron una somatometría y un perfil de lípidos al inicio y a los 6 meses de seguimiento. Se realizó un manual de alimentación con semaforización de los alimentos, poniendo de color rojo los alimentos que se deben consumir en la menor cantidad posible, además de incluir alimentos a tamaño real utilizando modelos educativos. Para comparar las variables cuantitativas antes y después de la intervención se transformaron las variables a su logaritmo y se aplicó la "t" de Student pareada. Resultados: se analizaron 41 pacientes. Posteriormente a la intervención se modificaron los parámetros del perfil lipídico; las concentraciones de HDL se incrementaron (41,0 mg/dL vs. 44,4 mg/dL, p = 0,048), mientras que las concentraciones de triglicéridos disminuyeron (227,1 mg/dL vs. 185.9 mg/dL, p = 0,007), lo cual persiste incluso una vez excluidos aquellos pacientes que se encontraban bajo tratamiento hipolipemiante (195 mg/dL vs. 171,6, p = 0,049). En cuanto al estado de dislipidemia, la hipertrigliceridemia disminuyó sin alcanzar la significancia (80,5 % vs. 62,5 %, p = 0,073). Conclusiones: la intervención nutricional mejoró las concentraciones de HDL y triglicéridos pasados 6 meses de la intervención en niños con ERC terminal.

A Multimodal Strategy to Reduce the Risk of Hospitalization/death in Ambulatory Patients with COVID-19.

BACKGROUND: Different interventions have been implemented worldwide for the house-hold monitoring of patients with mild COVID-19 to reduce the burden of healthcare systems and guarantee quality of care. Telephone follow up and treatment kits have not been evaluated in the context of a national-wide primary care program. AIM OF THE STUDY: To compare the risk of hospitalization and death for COVID-19 between ambulatory patients who received and those who did not receive a treatment kit and telephone follow-up in a developing country METHODS: A two-group comparative analysis was conducted using data from the medical information systems of the Mexican Institute of Social Security. We included a total of 28,048 laboratory-confirmed SARS-CoV-2 patients: 7,898 (28.2%) received a medical kit and 20,150 (71.8%) did not. The incidence rates of hospitalization and death combined were calculated. To identify significant associations between hospitalization or death and treatment medical kits, we calculated the risk ratios using a multivariate logistic model. RESULTS: The incidence of hospitalization was 6.14% in patients who received a kit and 11.71% in those who did not. Male sex, age, and a medical history of obesity, hypertension, diabetes, immunosuppression, or kidney disease were associated with increased risk of hospitalization or death. The risk rates were reduced in patients who received a medical kit or telephone follow-up. In the multivariate model, receiving a medical kit was associated with a lower risk of hospitalization or death from COVID-19: adjusted risk ratio 0.41 (95% confidence interval 0.36-0.47). CONCLUSION: Use of a multimodal strategy may reduce the risk of hospitalization and death in adult outpatients with mild COVID-19.

Screening for COVID-19 in Children Undergoing Elective Invasive Procedures.

OBJECTIVE: To report the frequency of asymptomatic infection with SARS-CoV-2 in pediatric patients undergoing invasive medical procedures in a tertiary pediatric hospital. METHODS: From June to October 2020, a SARS-CoV-2 real-time reverse-transcription polymerase chain reaction (rRT-PCR) test was performed for all pediatric patients scheduled to undergo an elective invasive procedure. None of the patients was symptomatic. The cycle threshold (Ct) values of the ORF1ab gene were recorded for all patients. RESULTS: A total of 700 patients were screened for SARS-CoV-2 infection. The median age was 5.7 y old. In total, 46.6% (n = 326) of the patients were male, and 53.4% (n = 374) were female. The most common underlying diseases were hemato-oncological (25.3%), gastrointestinal (24.9%), and genitourinary (10.3%). The main scheduled surgical-medical procedures were surgical treatment for acquired congenital diseases, biopsy sampling, local therapy administration, organ transplantation, and the placement of central venous catheters, among others. The SARS-CoV-2 rRT-PCR test was positive in 9.4% (66), and the median Ct value was 35.8. None of the patients developed COVID-19. CONCLUSIONS: The frequency of asymptomatic SARS-CoV-2 infection was detected in less than 10% of pediatric patients scheduled to undergo an elective invasive procedure in a tertiary hospital. This frequency is higher than those in reports from different countries.

The leptin/adiponectin ratio as prognostic marker for dyslipidemia during 1 year of follow-up in pediatric patients receiving kidney replacement therapy.

Introduction: Background: leptin and adiponectin are associated with cardiovascular disease in chronic kidney disease (CKD) patients and could be useful prognostic factors. Objectives. to explore the usefulness of the leptin/adiponectin ratio (LAR) to predict the presence or worsening of dyslipidemia during 1 year of follow-up in children receiving kidney replacement therapy (KRT). Material and methods: a prospective cohort study was performed. Pediatric KRT patients aged between 8 and 17 years who were undergoing hemodialysis or peritoneal dialysis were included. At enrollment, the lipid profile, adiponectin and leptin levels, and somatometric measurements, including body fat percentage, were determined. At the one-year follow-up, the lipid profile was reassessed. Results: of the 70 patients included, the median age was 13 years, and there was no sex predominance (52.8 % males). At the end of follow-up, the patients were divided into three groups: those without dyslipidemia (WOD), those who developed or experienced worsening of their dyslipidemia (DWD) and those with persistent dyslipidemia (PD). A LAR > 0.85 (OR, 16.7) and body fat percentage (OR, 1.46) were associated with an increased risk of PD and DWD at 12 months, independently of urea level, BMI Z-score, benzafibrate treatment, CKD progression time, and replacement treatment. Conclusions: a LAR > 0.85 and fat body percentage at the beginning of follow-up were strongly associated with the presence, persistence or worsening of dyslipidemia at the 12-month follow-up in children with KRT.

Introducción: Antecedentes: la leptina y la adiponectina se asocian con enfermedad cardiovascular en los pacientes con enfermedad renal crónica (ERC) y podrían ser factores pronósticos útiles. Objetivos: explorar la utilidad del cociente leptina/adiponectina (LAR) para predecir la presencia o empeoramiento de la dislipidemia durante 1 año de seguimiento en niños que reciben terapia de reemplazo renal (TRR). Material y métodos: se realizó un estudio de cohortes prospectivo. Se incluyeron pacientes pediátricos con TRR de entre 8 y 17 años que estaban en hemodiálisis o diálisis peritoneal. Al inicio del estudio se determinaron el perfil lipídico, los niveles de adiponectina y leptina, y las mediciones somatométricas, incluido el porcentaje de grasa corporal. En el seguimiento de un año, se reevaluó el perfil de lípidos. Resultados: de los 70 pacientes incluidos, la mediana de edad fue de 13 años y no hubo predominio de sexo (52,8 % de varones). Al final del seguimiento, los pacientes se dividieron en tres grupos: aquellos sin dislipidemia (SD), aquellos que desarrollaron o experimentaron un empeoramiento de su dislipidemia (ED) y aquellos con dislipidemia persistente (PD). Un LAR > 0,85 (OR: 16,7) y el porcentaje de grasa corporal (OR: 1,46) se asociaron con un mayor riesgo de ED y PD a los 12 meses, independientemente del nivel de urea, la puntuación Z del IMC, el tratamiento con benzafibrato, el tiempo de progresión de la ERC y el tratamiento de reemplazo. Conclusiones: un LAR > 0,85 y el porcentaje de grasa corporal al inicio del seguimiento se asociaron fuertemente con la presencia, persistencia o empeoramiento de la dislipidemia a los 12 meses de seguimiento en niños con TRR.

[The pediatric patient at the end-of-life. A challenge for its identification and treatment. A survey in pediatricians and medical residents]. / El paciente pediátrico en etapa terminal: un reto para su identificación y tratamiento. Encuesta a médicos pediatras y residentes.

BACKGROUND: Identification of pediatric patients at the end-of-life is not easy because criteria used are based on adults' criteria. OBJECTIVES: In this survey we explore the children end-of-life definition pediatricians have, as well as to determine which interventions they use when caring a patient at end-of-life. SETTING: Tertiary referral pediatric hospital. PARTICIPANTS: Staff pediatricians (SP) and medical residents (MR). METHODS: A self-administrated questionnaire was built and validated. It contains five vignettes of pediatric patients: Two with WHO criteria for an end-of-life condition (EC) and three without an end-of-life condition (NEC). PARTICIPANTS identified each patient with or without an end-of-life condition, and which palliative actions they would perform accordingly Their responses were recorded in a 4-option Likert scale. Ordinal regression was used to assess if some of the participants' characteristics were related to the identification of an end-of-life condition. RESULTS: Response rate was 84.2% (128/152); of whom 63 were SP and 65 MR. EC cases were well identified in 90 and 93%, while NEC in 30 and 40%, respectively Palliative actions were more according in EC patients, but around 20% would not provide them. Among NEC patients, there were more disparities of palliative actions to be delivered, and it was statistically significantly. Ordinal regression showed that some participants' characteristics are associated to the appropriate identification of end-of-life patients; however, these factors were not consistent across the five scenarios. CONCLUSIONS: Among pediatricians, criteria of end-of-life conditions are not well established, neither the palliative actions. Educational interventions are needed to improve the quality of life of these children.