Lupus-like membranous nephropathy. Is it lupus? Report of 5 cases in a reference hospital in Mexico.

INTRODUCTION: Lupus nephritis requires antinuclear antibodies as classification criteria. There is a group of patients with nephrotic syndrome and conclusive histopathological findings for lupus nephritis, without classification criteria for systemic lupus erythematosus (SLE) or extrarenal manifestations. These groups of patients have been described as "lupus-like" nephritis or "renal-limited lupus nephritis". METHODS: Renal biopsy with histopathological evaluation with "full-house" immune-reactants in patients with negative antinuclear antibodies. RESULTS: We report four cases with nephrotic syndrome and one with hematuria-proteinuria syndrome: two with impaired glomerular filtration rate and three with preserved renal function; urinary sediment with hematuria without dysmorphia and without extrarenal manifestations for autoimmune disease, negative antinuclear antibodies (ANA) and anti-double stranded DNA (anti-dsDNA); normal C3 and C4 complement levels. Renal biopsy in all cases was consistent for lupus nephritis class V. All patients received treatment as lupus nephritis protocol; only one case received induction with cyclophosphamide and methylprednisolone boluses, the rest received mycophenolic acid and prednisone as induction and maintenance. Two of the cases induced with mycophenolic acid relapsed, requiring cyclophosphamide for 6 months, achieving complete remission. All patients received renin-angiotensin-aldosterone system blockade and hydroxychloroquine. At follow-up, 4 cases still have negative antibodies and are without extrarenal manifestations for SLE classification criteria. The other case, during pregnancy several years after initial diagnosis, had preeclampsia with nephrotic proteinuria and a new determination of positive ANA and anti-dsDNA antibodies, complement levels below normal limits. CONCLUSION: The follow-up of patients with membranous glomerulopathy must be close; lupus like nephritis may be the first manifestation of the disease.

Identification of metabolic markers in patients with type 2 Diabetes by Ultrafast gas chromatography coupled to electronic nose. A pilot study.

Metabolomics is a potential tool for the discovery of new biomarkers in the early diagnosis of diseases. An ultra-fast gas chromatography system equipped to an electronic nose detector (FGC eNose) was used to identify the metabolomic profile of Volatile Organic Compounds (VOCs) in type 2 diabetes (T2D) urine from Mexican population. A cross-sectional, comparative, and clinical study with translational approach was performed. We recruited twenty T2D patients and twenty-one healthy subjects. Urine samples were taken and analyzed by FGC eNose. Eighty-eight compounds were identified through Kovats's indexes. A natural variation of 30% between the metabolites, expressed by study groups, was observed in Principal Component 1 and 2 with a significant difference (p < 0.001). The model, performed through a Canonical Analysis of Principal coordinated (CAP), allowed a correct classification of 84.6% between healthy and T2D patients, with a 15.4% error. The metabolites 2-propenal, 2-propanol, butane- 2,3-dione and 2-methylpropanal, were increased in patients with T2D, and they were strongly correlated with discrimination between clinically healthy people and T2D patients. This study identified metabolites in urine through FGC eNose that can be used as biomarkers in the identification of T2D patients. However, more studies are needed for its implementation in clinical practice.

Desempeño de las ecuaciones para estimar la tasa de filtración glomerular en pacientes mexicanos receptores de trasplante renal.

INTRODUCTION: The management of kidney transplant recipients requires glomerular filtration rate (GFR) monitoring, which is an indicator of graft primary function and patient survival. OBJECTIVE: To evaluate the performance of different creatinine or cystatin-based formulas in the estimation of glomerular filtration rate in Mexican patients receiving kidney transplantation. METHOD: 30 transplant recipients were included, in whom the glomerular filtration rate was measured by means of iothalamate, and was also calculated using seven equations based on cystatin or creatinine. RESULTS: The formula with the best performance was the one proposed by the chronic kidney disease epidemiology collaboration (CKD-EPI), with a bias of -2.4 mL/min/1.73 m2 and an accuracy of 9.6; 96.7 % of patients were within 30 % of the measured GFR. The second best formula was the modification of diet in renal disease (MDRD) equation. Cystatin-based equations showed a poor performance. CONCLUSIONS: Our study suggests that, in Mexican patients receiving kidney transplantations, the best equations to estimate GFR are the CKD-EPI and MDRD equations.

INTRODUCCIÓN: El manejo de los pacientes receptores de trasplante renal requiere vigilancia de la tasa de filtrado glomerular (TFG), la cual es un indicador de la función primaria del injerto y de la supervivencia del paciente. OBJETIVO: Evaluar el rendimiento en la estimación de la función renal de diferentes fórmulas basadas en creatinina o cistatina en pacientes mexicanos receptores de trasplante renal. MÉTODO: Se incluyeron 30 pacientes receptores de trasplante renal en quienes se midió tasa de filtrado glomerular por iodotalamato, la cual también se calculó por siete ecuaciones basadas en cistatina o creatinina. RESULTADOS: La fórmula con mejor desempeño fue la propuesta por CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration), con un sesgo de −2.4 mL/minuto/1.73 m2 y precisión de 9.6; 96.7 % estaba dentro de 30 % de la tasa de filtrado glomerular medida. La segunda mejor ecuación fue la MDRD (Modification of Diet in Renal Disease). Las ecuaciones basadas en cistatina mostraron pobre desempeño. CONCLUSIONES: Nuestro estudio sugiere que en pacientes mexicanos receptores de trasplante renal las mejores ecuaciones para estimar la TFG son CKD y MDRD.

Renal function assessment in patients with systemic lupus erythematosus.

Few studies have evaluated the glomerular filtration rate (GFR) in patients with systemic lupus erythematosus (SLE). Even though the National Kidney Foundation (NKF) suggests using the equations to estimate GFR, rheumatologists continue using creatinine clearance (CCl). The main objective of our study was the assessment of different equations to estimate GFR in patients with SLE: Simplified MDRD study equation (sMDRD), CCl, Cockcroft Gault (CG), CG calculated with ideal weight (CGi), Mayo Clinic Quadratic (MCQ), and Chronic Kidney Disease Epidemiology Collaboration Equation (CKD-EPI). CKD-EPI was considered as the reference standard, and it was compared with the other equations to evaluate bias, correlation (r), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), percentage of measurement of GFR between 70-130% of GFR measured through CKD-EPI (P30) and to compute the ROC curves. Adequacy of the 24-h urine collection was evaluated. To classify patients into GFR < 60 ml/min/1.73 m(2), the best sensitivity and NVP were obtained with sMDRD: the best PPV and specificity with MCQ. P30 was 99.3% with sMDRD, 77.5% CCl, 91.7% CG, 96.7% CGi, and 77.2% with MCQ. The lowest bias was for sMDRD and the highest for CCl. Only 159 (52.6%) urine collections were considered adequate, and when these patients were re-evaluated, the statistical results improved for CCl. CGi was better in general than CG. CCl should not be considered as an adequate GFR estimation. Ideal weight is better than real weight to calculate GFR through CG in patients with SLE.

[Experience in kidney transplantation from 1999 to 2011 at the Hospital Central Dr. Ignacio Morones Prieto, San Luis Potosí]. / Experiencia en trasplante renal, de 1999-2011, en el Hospital Central Dr. Ignacio Morones Prieto de San Luis Potosi.

INTRODUCTION: In April 1991 was performed the first kidney transplant at the Hospital Central Dr. Ignacio Morones Prieto. In August 1999, formally started the kidney transplant program. OBJECTIVE: To describe the experience in kidney transplant at HCIMP. MATERIALS AND METHODS: Retrospective cohort study, which includes all kidney transplants performed during the period August 1999 to June 2011. We excluded patients whose medical record was eliminated or with incomplete data for analysis. It describes the general characteristics of kidney transplant recipients, transplant-related variables, initial immunosuppression and complications. The survival analysis was performed using the Kaplan-Meier method. The curves were compared using the log-rank test. RESULTS: From August 1999 to June 2011 were performed 517 kidney transplants at Central Hospital, of which 411 patients were analyzed. Ten years overall graft-survival was 73%. Both, the history of infection or acute rejection were associated with lower graft survival. The main cause of death, in our population, was infectious processes. CONCLUSION: Graft survival at 10 years was 73%, which is similar to that reported in the literature. A history of acute rejection and infection are factors associated with lower survival.

Application of the Electronic Nose in Predicting Preeclampsia in High-risk Pregnancies. Pilot Study.

BACKGROUND: Preeclampsia is a syndrome that affects 2-8 % of pregnancies worldwide and is the leading cause of maternal death. Therefore, early detection is crucial to identify women who require clinical monitoring during pregnancy and to evaluate new preventive therapies before clinical symptoms occur. METHODS: The chemical fingerprints of the urine from three study groups pregnant with Preeclampsia, Healthy Pregnant (HP) and pregnant at High Risk of Preeclampsia (HRP) were evaluated using an electronic nose and the data obtained were subjected to principal component analysis (PCA), Canonical Analysis of Principal Coordinates (CAP), Partial Least Squares - Discriminant Analysis (PLS-DA) and ROC curves to determine the diagnostic power of the test. RESULTS: A separation was found between the patients with preeclampsia and HP explaining 99% of the variability of the data. Subsequently, a CAP was obtained with a correct classification of 100%, and the PLS-DA was obtained an accuracy of 88%. With the results of axis CAP1, a ROC curve was performed resulting in a sensitivity of 100% and a specificity of 95.5%. Based on the CAP model it was found that 36% (n=9) of the HRP patients would develop preeclampsia based on the metabolites found in urine. CONCLUSION: metabolomics can be used as a tool for early detection of preeclampsia in high-risk pregnant women, using portable olfactory technology.

Performance of the equations to estimate the glomerular filtration rate in Mexican patients receiving kidney transplantation / Desempeño de las ecuaciones para estimar la tasa de filtración glomerular en pacientes mexicanos receptores de trasplante renal

Abstract Introduction: The management of kidney transplant recipients requires glomerular filtration rate (GFR) monitoring, which is an indicator of graft primary function and patient survival. Objective: To evaluate the performance of different creatinine or cystatin-based formulas in the estimation of glomerular filtration rate in Mexican patients receiving kidney transplantation. Method: 30 transplant recipients were included, in whom the glomerular filtration rate was measured by means of iothalamate, and was also calculated using seven equations based on cystatin or creatinine. Results: The formula with the best performance was the one proposed by the chronic kidney disease epidemiology collaboration (CKD-EPI), with a bias of −2.4 mL/min/1.73 m2: and an accuracy of 9.6; 96.7 % of patients were within 30 % of the measured GFR. The second best formula was the modification of diet in renal disease (MDRD) equation. Cystatin-based equations showed a poor performance. Conclusions: Our study suggests that, in Mexican patients receiving kidney transplantations, the best equations to estimate GFR are the CKD-EPI and MDRD equations.