Assessment of urinary TWEAK levels in Mexican patients with untreated lupus nephritis: An exploratory study

Objectives: Urinary levels of TWEAK (uTWEAK) may be correlated with the degree of lupus nephritis (LN) activity. Our objective was to determine the sensitivity and specificity of uTWEAK in Mexican patients with untreated active lupus nephritis. Methods: An exploratory study was performed; four groups of patients were analyzed as follows: 1) patients with systemic lupus erythematosus (SLE) without renal activity (SLE-LN), 2) patients with SLE with renal activity (SLE + LN), 3) patients with other types of glomerulopathy (glomerulonephritis, GMN), 4) and healthy patients (controls). Results: In all, 44 patients, with an average age of 35.9 ± 11.5 years, were evaluated. uTWEAK levels were higher in patients with SLE + LN compared with patients in the other groups: SLE + LN 12.88 ± 8.33, SLE-LN 3.12 ± 2.31, GMN 4.36 ± 2.31 and controls 2.41 ± 1.94 pg/mg Cr (p = 0.007). A total of 72.7% of the cases had renal activity index scores above 12, and 90.9% of the cases had scores of chronicity below 6 points. Receiver Operating Characteristic (ROC) curve analysis revealed that uTWEAK levels above 4.91 pg/mg Cr had a sensitivity of 81% and a specificity of 75% for the diagnosis of renal activity due to lupus, with an area under the curve of 0.876 (95% CI: 0.75â0.99). However, no significant correlation was observed between the levels of uTWEAK and the histological findings specific to the activity and chronicity associated with SLE. Conclusions: Our study revealed that uTWEAK can adequately distinguish renal activity due to lupus, but cannot predict the degree of histological activity in Mexican patients with active lupus nephropathy. Resumen: Objetivos: Los niveles urinarios de TWEAK (uTWEAK) pueden correlacionarse con el grado de actividad de nefritis lúpica (NL). Nuestro objetivo fue determinar la sensibilidad y especificidad de los uTWEAK en pacientes mexicanos con NL activa sin tratamiento farmacológico previo. Metodología: Se realizó un estudio exploratorio en el que se incluyeron 4 grupos de pacientes: 1) pacientes con lupus eritematoso sistémico sin actividad renal (LES-NL); 2) pacientes con lupus eritematoso sistémico con actividad renal (LES+NL); 3) pacientes con otras glomerulopatías y 4) controles sanos. Resultados: La edad promedio de los 44 pacientes fue de 35,9 ± 11,5 años. Los uTWEAK fueron más elevados en pacientes con LES+NL comparados con los otros grupos: LES + NL (12,88 ± 8,33), LES-NL (3,12 ± 2,31), otras glomerulopatías (4,36 ± 2,31) y grupo control (2,41 ± 1,94 pg/mgCr) (p = 0,007). En el 72,7% de los casos se observó un índice de actividad renal mayor a 12 puntos y en el 90,9% de los casos los índices de cronicidad estaban por debajo de 6 puntos. La curva ROC reveló que los niveles urinarios por encima de 4,91 pg/mg Cr tienen sensibilidad del 81% y especificidad del 75% para el diagnóstico de actividad renal secundaria a lupus, con área debajo de la curva de 0,876 (IC 95%: 0,75-0,99). Sin embargo, no se observó correlación significativa entre los uTWEAK y los hallazgos histológicos específicos de actividad y cronicidad asociados a LES. Conclusiones: Nuestro estudio revela que los uTWEAK pueden distinguir adecuadamente actividad renal secundaria a lupus, pero no predicen el grado de actividad histológica en pacientes mexicanos con NL activa. Keywords: Lupus nephritis, TWEAK, Urinary biomarkers, Palabras clave: Nefritis lúpica, TWEAK, Biomarcadores urinario

Behavior of Oxidative Stress Markers in Alcoholic Liver Cirrhosis Patients

Alcohol is the most socially accepted addictive substance worldwide, and its metabolism is related with oxidative stress generation. The aim of this work was to evaluate the role of oxidative stress in alcoholic liver cirrhosis (ALC). This study included 187 patients divided into two groups: ALC, classified according to Child-Pugh score, and a control group. We determined the levels of reduced and oxidized glutathione (GSH and GSSG) and the GSH/GSSG ratio by an enzymatic method in blood. Also, protein carbonyl and malondialdehyde (MDA) content were estimated in serum. MDA levels increased in proportion to the severity of damage, whereas the GSH and GSSG levels decreased and increased, respectively, at different stages of cirrhosis. There were no differences in the GSH/GSSG ratio and carbonylated protein content between groups. We also evaluated whether the active consumption of or abstinence from alcoholic beverages affected the behavior of these oxidative markers and only found differences in the MDA, GSH, and GSSG determination and the GSH/GSSG ratio. Our results suggest that alcoholic cirrhotic subjects have an increase in oxidative stress in the early stages of disease severity and that abstinence from alcohol consumption favors the major antioxidant endogen: GSH in patients with advanced disease severity