[Changes in body composition according to kidney damage in patients with type 2 diabetes mellitus]. / Modificaciones en la composición corporal según el daño renal en pacientes con diabetes mellitus tipo 2.

OBJECTIVE: To know the relationship between total body composition and the stage of kidney damage, according to the K/DOQI classification, in patients with type 2 diabetes mellitus (T2DM). METHODS: Under a correlation design, adults with T2DM were studied. Age, evolution time, fat and lean mass, fat percentage, total water, body index mass (BMI), creatinine clearance by Cockroft-Gault (CrCCG), glucose, HbA1c, proteinuria and microalbuminuria were determined. T test to compare independent means and Spearman correlation were used. RESULTS: The study included 60 men (23.4%) and 196 women (76.6%). There were no differences by gender when comparing age, BMI, duration of T2DM, blood glucose and HbA1c. The analysis showed a direct relationship between BMI (r = 0.281), the amount of fat mass (r = 0.360), lean tissue (r = 0.158), and water (r = 0.176) with the CrCCG (p < 0.0001). The biggest change in body composition, due to fat mass, was observed in chronic kidney disease stages 1-3, in which BMI had a good correlation with fat mass (r = 0.80, p < 0.001). CONCLUSIONS: Fat mass is inversely related to the stage of kidney damage in patients with T2DM.

Human IgG antibody responses to severe acute respiratory syndrome coronavirus 2 viral antigens receptor-binding domain, spike, and nucleocapsid, in vaccinated adults from Merida, Mexico.

Several vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been approved for controlling the coronavirus disease 2019 (COVID-19) pandemic worldwide. Antibody response is essential to understand the immune response to different viral targets after vaccination with different vaccine platforms. Thus, the main aim of this study was to describe how vaccination with two distinct SARS-CoV-2 vaccine preparations elicit IgG antibody specific responses against two antigenically relevant SARS-CoV-2 viral proteins: the receptor-binding domain (RBD) and the full-length spike (S). To do so, SARS-CoV-2 protein specific in-house enzyme-linked immunosorbent assays (ELISAs) were standardized and tested against serum samples collected from 89 adults, recipients of either a single-dose of the Spike-encoding mRNA-based Pfizer/BioNTech (Pf-BNT) (70%, 62/89) or the Spike-encoding-Adenovirus-5-based CanSino Biologics Inc. (CSBIO) (30%, 27/89) in Merida, Mexico. Overall, we identified an IgG seroconversion rate of 88% (68/78) in all vaccinees after more than 25 days post-vaccination (dpv). Anti-RBD IgG-specific responses ranged from 90% (46/51) in the Pf-BNT vaccine at 25 dpv to 74% (20/27) in the CSBIO vaccine at 42 dpv. Compared to the S, the RBD IgG reactivity was significantly higher in both Pf-BNT (p < 0.004) and CSBIO (p < 0.003) vaccinees. Interestingly, in more than 50% of vaccine recipients, with no history of COVID-19 infection, antibodies against the nucleocapsid (N) protein were detected. Thus, participants were grouped either as naïve or pre-exposed vaccinees. Seroconversion rates after 25 and more dpv varies between 100% in Pf-BNT (22/22) and 75% (9/12) in CSBIO pre-exposed vaccinees, and 89% (26/29) and 73% (11/15) in Pf-BNT and CSBIO naïve vaccine recipients, respectively. In summary, observed seroconversion rates varied depending on the type of vaccine, previous infection with SARS-CoV-2, and the target viral antigen. Our results indicate that both vaccine preparations can induce detectable levels of IgG against the RBD or Spike in both naïve and SARS-CoV-2 pre-exposed vaccinees. Our study provides valuable and novel information about the serodiagnosis and the antibody response to vaccines in Mexico.

[Four years experience in the follow up of nursing children with urolithiasis]. / Litiasis urinaria en lactantes. Seguimiento a cuatro años.

OBJECTIVE: to describe clinical data, metabolic profile, treatment and evolution of a nursing children cohort with urolithiasis. METHODS: using a descriptive, prospective and longitudinal design, were registered all patients with urolithiasis, of Pediatric Division at the Hospital General "Agustín O'Horán," in Yucatan, Mexico. We included all patients who were 36 months old and younger. We did not include children with malformations or associated disease which causes urolithiasis. Clinical and metabolic profiles, evaluation of the applied treatment as well as an evolution by four years period were done. RESULTS: 63 patients were recruited with ages ranging from 2 to 36 months; 39 (61.9 %) were male. The most common clinical signs were crying upon urination (49.2 %), urinary retention (31.7 %), hematuria (30.2 %), and pollakiuria (28.6 %). Calculus were most frequently located in the kidney (58.7 %). The most common complications were acute urinary tract infection (61.9 %), malnutrition (47.6 %) and acute renal failure (12.7 %). Documented metabolic alterations included hyperuricosuria (57.1 %), hypomagnesiuria (11.1 %) and hypercalciuria (9.5 %). CONCLUSIONS: urolithiasis should be suspected in children with crying upon urination and urinary symptoms; it should be considered among the different causes of renal failure; hyperuricosuria was the most frequent metabolic alteration.

Dengue seroprevalence in a cohort of schoolchildren and their siblings in Yucatan, Mexico (2015-2016).

BACKGROUND: The implementation of vector control interventions and potential introduction new tools requires baseline data to evaluate their direct and indirect effects. The objective of the study is to present the seroprevalence of dengue infection in a cohort of children 0 to 15 years old followed during 2015 to 2016, the risk factors and the role of enhanced surveillance strategies in three urban sites (Merida, Ticul and Progreso) in Yucatan, Mexico. METHODS: A cohort of school children and their family members was randomly selected in three urban areas with different demographic, social conditions and levels of transmission. We included results from 1,844 children aged 0 to 15 years. Serum samples were tested for IgG, NS1 and IgM. Enhanced surveillance strategies were established in schools (absenteeism) and cohort families (toll-free number). RESULTS: Seroprevalence in children 0 to 15 years old was 46.8 (CI 95% 44.1-49.6) with no difference by sex except in Ticul. Prevalence increased with age and was significantly lower in 0 to 5 years old (26.9%, 95% CI:18.4-35.4) compared with 6 to 8 years old (43.9%, 95% CI:40.1-47.7) and 9 to 15 years old (61.4%, 95% CI:58.0-64.8). Sharing the domestic space with other families increased the risk 1.7 times over the individual families that own or rented their house, while risk was significantly higher when kitchen and bathroom were outside. Complete protection with screens in doors and windows decreased risk of infection. Seroprevalence was significantly higher in the medium and high risk areas. CONCLUSIONS: The prevalence of antibodies in children 0 to 15 years in three urban settings in the state of Yucatan describe the high exposure and the heterogenous transmission of dengue virus by risk areas and between schools in the study sites. The enhanced surveillance strategy was useful to improve detection of dengue cases with the coincident transmission of chikungunya and Zika viruses.

Temporal distribution and genetic variants in influenza A(H1N1)pdm09 virus circulating in Mexico, seasons 2012 and 2013.

The 2012 and 2013 annual influenza epidemics in Mexico were characterized by presenting different seasonal patterns. In 2012 the A(H1N1)pdm09 virus caused a high incidence of influenza infections after a two-year period of low circulation; whereas the 2013 epidemic presented circulation of the A(H1N1)pdm09 virus throughout the year. We have characterized the molecular composition of the Hemagglutinin (HA) and Neuraminidase (NA) genes of the A(H1N1)pdm09 virus from both epidemic seasons, emphasizing the genetic characteristics of viruses isolated from Yucatan in Southern Mexico. The molecular analysis of viruses from the 2012 revealed that all viruses from Mexico were predominantly grouped in clade 7. Strikingly, the molecular characterization of viruses from 2013 revealed that viruses circulating in Yucatan were genetically different to viruses from other regions of Mexico. In fact, we identified the occurrence of two genetic variants containing relevant mutations at both the HA and NA surface antigens. There was a difference on the temporal circulation of each genetic variant, viruses containing the mutations HA-A141T / NA-N341S were detected in May, June and July; whereas viruses containing the mutations HA-S162I / NA-L206S circulated in August and September. We discuss the significance of these novel genetic changes.

[Relationship between body fat and creatinine clearence in adults with and without diabetes mellitus]. / Relación entre grasa corporal y depuración de creatinina en adultos con y sin diabetes mellitus.

BACKGROUND: Obesity is a risk factor for renal damage. This study aimed to determine the relationship between body fat percent and creatinine clearance in adult patients with and without type 2 diabetes mellitus (T2DM). METHODS: An observational prospective cross-correlation study was carried out among adults with and without T2DM between 18 and 60 years of age. It was determined the time of evolution with T2DM, as well as fat percentage (FP), body mass index (BMI), creatinine clearance (Cockroft-Gault [CrCCG]), glycemia and micro/macroalbuminuria. The correlation between CrCCG and FP was determined by Spearman's test. RESULTS: 174 subjects were included in this study. Obesity by BMI and FP in subjects with and without T2DM was similar. Of the studied subjects, 12.6 % didn't have kidney damage and 50.7 % had increased risk of renal disease; the frequencies for stages 1-4 of kidney damage were 12.0, 20.1, 4.0 and 0.6 %, respectively. Spearman's test showed a direct relationship between FP and CrCCG, higher in diabetics (r = 0.418, p < 0.0001) than in non-diabetics (p = 0.327, p < 0.0001). CONCLUSIONS: The FP was correlated directly with the CrCCG in subjects with and without T2DM; therefore, we can conclude that the greater the kidney damage, the smaller the fat porcentage in the study sample.

Introducción: la obesidad es un factor de riesgo para daño renal. El objetivo del estudio fue conocer la relación entre el porcentaje de grasa corporal (PG) y la depuración de creatinina en pacientes adultos con y sin diabetes mellitus 2 (DM2). Métodos: estudio observacional, prospectivo, transversal de correlación. Se evaluaron adultos entre 18 y 60 años, con y sin DM2. Se determinó el tiempo de evolución con DM2, el PG, el índice de masa corporal (IMC), la depuración de creatinina (Cockroft-Gault [DCrCG]), la glicemia y la micro/macroalbuminuria. Mediante la prueba de Spearman se determinó la correlación entre DCrCG y PG. Resultados: se incluyeron 174 sujetos. La frecuencia de obesidad por IMC y PG en sujetos con y sin DM2 fue similar. El 12.6 % no tuvo daño renal y el 50.7 % tuvo riesgo aumentado de enfermedad renal. Las frecuencias para los estadios 1 a 4 fueron 12.0, 20.1, 4.0 y 0.6 %, de forma respectiva. La prueba de Spearman mostró relación directa entre PG y DCrCG, mayor en diabéticos (r = 0.418 frente a r = 0.327, p < 0.0001). Conclusiones: el PG corporal se correlacionó en forma directa con la DCrCG en sujetos con y sin DM2; se infiere que a mayor daño renal, menor grasa tiene la población evaluada.

[Kidney function in marginalized population: a pilot study]. / Función renal en un grupo marginado de la población. Estudio piloto.

BACKGROUND: Chronic kidney disease (CKD) is a public health problem; more than 6 % of worldwide population suffers from it. Low education and socioeconomic status, as well as limited access to medical care increase the probability of kidney damage. The objective was to evaluate and classify renal function in Yucatan's marginalized population. METHODS: A transversal descriptive survey was carried out among non-hospitalized adults of a general hospital. The study population included marginalized subjects (confirmed by socioeconomic survey), without oedema, pregnancy or diabetes mellitus. Renal function was evaluated by glomerular filtration rate. Patients were staged according to KDOQI guidelines. Likewise, weight, height, body mass index (BMI), fat percentage and blood pressure were measured. The results were compared between gender groups as well as rural and urban population. RESULTS: 165 subjects were included (83 % female). High risk of kidney damage was observed in 44.2 % of patients; 1.8 %, 49.1 %, and 4.8 % were in stages 1 to 3, respectively. There was no difference when comparing data between different groups. CONCLUSIONS: This study found high prevalence of CKD in Yucatan's marginalized population.

INTRODUCCIÓN: la enfermedad renal crónica (ERC) es un problema de salud pública. A nivel mundial, más del 6 % de la población la padece. Tener un nivel educativo y socioeconómico bajo, así como acceso limitado a los servicios médicos incrementan la probabilidad de daño renal. Los objetivos de esta investigación fueron evaluar y clasificar la función renal de la población marginada de Yucatán. MÉTODOS: estudio observacional, prospectivo, transversal, descriptivo, en una muestra no probabilística consecutiva, en adultos del área de consulta externa de un hospital general. Se incluyeron sujetos marginados (confirmado por encuesta socioeconómica), sin edema, embarazo ni diabetes mellitus. Se realizaron pruebas de función renal; se calculó filtrado glomerular y se estadificaron las enfermedades de los pacientes, según guías KDOQI. Se determinó peso, talla, índice de masa corporal (IMC), porcentaje de grasa y presión arterial. Se compararon los resultados entre grupos por sexo y por población rural y urbana. RESULTADOS: se incluyeron 165 sujetos (83 % mujeres). El 44.2 % presentó un riesgo alto de daño renal; 8, 49.1 y 4.8 % estuvieron en estadios del 1 al 3, respectivamente. No hubo diferencia cuando se compararon los datos entre los diferentes grupos estudiados. CONCLUSIONES: se encontró alta prevalencia de ERC en la población marginada de Yucatán.

Metabolic abnormalities and polymorphisms of the vitamin D receptor (VDR) and ZNF365 genes in children with urolithiasis.

Composition of urinary stones in children from Yucatán, México, is calcium and uric acid. Polymorphisms in VDR and ZNF365 genes have been associated to calcium and uric acid lithiasis, respectively. We evaluated the association of polymorphisms TaqI and FokI of VDR gene and Ala62Thr of ZNF365 gene with the metabolic disorders (MD) in children with urolithiasis (UL). We included 109 children with UL. Creatinine, calcium, phosphorus, magnesium, uric acid, oxalates and citrates were measured in fresh urine. Urinary indices were calculated for determining the MD. VDR and ZNF365 polymorphisms were determined by PCR-RFLP. Genotype frequencies were compared with the frequency of MD and with the averages of excretion of the analytes, using the statistical package STATA 11.0. The most frequent MD were hypocitraturia (35.8 %) and hyperuricosuria (22.9 %). The comparison of genotype frequencies with the frequency of MD did not show significant differences (p > 0.05). The comparison of the urinary excretion averages of analytes with respect to the genotype showed that GG homozygotes have higher concentrations of uric acid and citrate than AG heterozygotes (p = 0.03), and that fF heterozygotes have lower concentrations of citrate (p = 0.009). Hypocitraturia and hyperuricosuria were the most common metabolic disorders. The frequency of MD is not associated with polymorphisms. However, in children with urolithiasis of Yucatan, GG homozygotes excrete higher concentrations of uric acid and citrates, and fF heterozygotes have lower concentrations of citrates.

Prevalence and risk factors for urolithiasis in primary gout: is a reappraisal needed?

OBJECTIVE: To assess the prevalence and risk factors for urolithiasis in primary gout. METHODS: One hundred forty patients with primary gout were studied. Urolithiasis was defined as a history of urolithiasis, or nephrolithiasis detected via ultrasonography in patients with no previous record of urolithiasis. Patient age, duration of gout, presence of tophi, obesity, alcoholism, high blood pressure, diabetes, hyperlipidemia, family history of urolithiasis, daily urine output, uricemia, urine pH, FeNa, FeUrate, urine pH/FeUrate index, and daily urine excretion of urate, sodium, calcium and potassium were compared between lithiasic and non-lithiasic subjects. RESULTS: Fifty-five (39%; 95% CI 31-47) patients had urolithiasis, of which 37 (26%) were diagnosed by clinical history and 18 (13%) by ultrasonography. Patients with a silent kidney stone diagnosed by ultrasound tended to have shorter evolution of gout. Aside from urinary H+ ion concentration (lithiasic subjects 5.17 +/- 3.9 microM/l; non-lithiasic subjects 3.80 +/- 3.01 microM/l; p = 0.02), no difference was found between lithiasic and non-lithiasic subjects for the other variables studied. CONCLUSION: Ultrasonography increased the probability of diagnosing urolithiasis by 50%, meaning the prevalence of urolithiasis in gout is likely higher than previously reported. A higher urinary H+ ion concentration was the only variable associated with urolithiasis. Due to advances in diagnosis of gout and urolithiasis, as well as biochemical assays, the prevalence and risk factors for urolithiasis in gout require reassessment.

Factors associated with musculoskeletal disability and chronic renal failure in clinically diagnosed primary gout.

OBJECTIVE: . To assess the association between a set of sociodemographic, clinical, and biochemical variables and the presence of musculoskeletal (MSK) disability and chronic renal failure in patients with primary gout defined using Wallace criteria. METHODS: Subjects were 90 patients with primary gout (98% male, age 54 +/- 12 years, 11.3 +/- 9.8 years with gout). A cohort nested case-control design was used. Analysis was done of the association between MSK disability or renal failure and a series of variables: age; duration of gout; body mass index; education level; income; serum glucose, cholesterol, triglycerides, and uric acid; Health Assessment Questionnaire score; obesity; family history of gout; high blood pressure; alcoholism; smoking habit; presence of tophi; ischemic cardiopathy; and use of colchicine, glucocorticoids, nonsteroidal antiinflammatory drug, or allopurinol. RESULTS: Forty-two patients (47%) had MSK disability, and 25/80 (31%) had renal failure. On logistic regression, presence of tophi (relative risk 4.3, 95% confidence interval 1.2-15.1), hypertriglyceridemia (RR 3.4, 95% CI 1.1-10), and history of ischemic heart disease (RR 8.3, 95% CI 1.6-41) were associated with MSK disability. Patient age was the only variable associated with renal failure. CONCLUSION: Optimal medical control of gout and its comorbidities may improve prognosis of gout, as suggested by our findings, in which a marker for poorly controlled gout such as presence of tophi in addition to high blood triglyceride levels and ischemic heart disease were associated with MSK disability. Older age was the only factor associated with renal failure, although this may only reflect declining renal function in the elderly.