Sodium-glucose cotransporter 2 inhibition in primary and secondary glomerulonephritis.

BACKGROUND: The role of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in the management glomerular/systemic autoimmune diseases with proteinuria in real-world clinical settings is unclear. METHODS: This is a retrospective, observational, international cohort study. Adult patients with biopsy-proven glomerular diseases were included. The main outcome was the percentage reduction in 24-h proteinuria from SGLT2i initiation to 3, 6, 9 and 12 months. Secondary outcomes included percentage change in estimated glomerular filtration rate (eGFR), proteinuria reduction by type of disease and reduction of proteinuria ≥30% from SGLT2i initiation. RESULTS: Four-hundred and ninety-three patients with a median age of 55 years and background therapy with renin-angiotensin system blockers were included. Proteinuria from baseline changed by -35%, -41%, -45% and -48% at 3, 6, 9 and 12 months after SGLT2i initiation, while eGFR changed by -6%, -3%, -8% and -10.5% at 3, 6, 9 and 12 months, respectively. Results were similar irrespective of the underlying disease. A correlation was found between body mass index (BMI) and percentage proteinuria reduction at last follow-up. By mixed-effects logistic regression model, serum albumin at SGLT2i initiation emerged as a predictor of ≥30% proteinuria reduction (odds ratio for albumin <3.5 g/dL, 0.53; 95% CI 0.30-0.91; P = .02). A slower eGFR decline was observed in patients achieving a ≥30% proteinuria reduction: -3.7 versus -5.3 mL/min/1.73 m2/year (P = .001). The overall tolerance to SGLT2i was good. CONCLUSIONS: The use of SGLT2i was associated with a significant reduction of proteinuria. This percentage change is greater in patients with higher BMI. Higher serum albumin at SGLT2i onset is associated with higher probability of achieving a ≥30% proteinuria reduction.

Long-term follow-up of an IgA nephropathy cohort: outcomes and risk factors.

AIM: IgA nephropathy (IgAN), the most common glomerulopathy worldwide and in Uruguay, raised treatment controversies. The study aimed to analyze long-term IgAN outcomes and treatment. METHODS: A retrospective analysis of a Uruguayan IgAN cohort, enrolled between 1985 and 2009 and followed up until 2020, was performed. The Ethics Committee approved the study. The inclusion criteria were (a) biopsy-proven IgAN; (b) age ≥12 years; and (c) available clinical, histologic, and treatment data. The patients were divided into two groups, with immunosuppressive (IS) or without (NoIS) treatment. Outcomes (end-stage kidney disease/kidney replacement therapy [ESKD/KRT] or all-cause death) were obtained from mandatory national registries. RESULTS: The study population included 241 patients (64.7% men), median age 32 (19.5) years, baseline blood pressure <130/80 mmHg in 37%, and microhematuria in 67.5% of patients. Baseline proteinuria, glomerulosclerosis, and a higher crescent percentage were significantly more frequent in the IS group. Proteinuria improved in both groups. Renal survival at 20 years was 74.6% without difference between groups. In the overall population and in the NoIS group, bivariate Cox regression analysis showed that baseline proteinuria, endocapillary hypercellularity, tubule interstitial damage, and crescents were associated with a higher risk of ESKD/KRT or death, but in the IS group, proteinuria and endocapillary hypercellularity were not. In the multivariate Cox analysis, proteinuria in the NoIS group, crescents in the IS group and tubule interstitial damage in both groups were independent risk factors. CONCLUSION: The IS group had more severe risk factors than the NoIS group but attained a similar outcome.

Which Patients with Obesity Are at Risk for Renal Disease?

Obesity-related glomerulopathy (ORG) is an increasingly recognized cause of end-stage kidney disease. The most common clinical presentation is a slowly increasing nonnephrotic proteinuria that is followed by a progressive decline of kidney function. Key histological findings are glomerulomegaly and lesions of focal and segmental glomerulosclerosis. A central pathogenic mechanism is the increased sodium reabsorption by proximal tubules that typically accompanies obesity. This causes a decrease in the offer of sodium to the macula densa in the distal nephron, which results in a vasodilation of afferent glomerular arterioles and glomerular hyperfiltration. From a clinical point of view, it is essential to differentiate focal segmental glomerulosclerosis secondary to obesity from primary glomerular processes, which requires a careful differential diagnosis. Diet-induced weight loss, bariatric surgery, and renin-angiotensin blockers are the fundamental therapeutic measures in ORG. The recently developed sodium-glucose cotransporter 2 inhibitors and glucagon-like peptide 1 agonist represent a significant advance in renal protection and will probably improve clinical kidney outcomes in ORG.

Recomendaciones sobre la vacunación contra SARS-CoV-2 / COVID-19 en pacientes con enfermedad renal y trasplante renal / Recommendations for the SARS-CoV-2 vaccination of patients with kidney disease and transplant recipients / Recomendações sobre vacinação contra SARS-CoV-2 / COVID-19 em pacientes com doença renal e transplante renal

Resumen: Este documento de recomendaciones tiene como objetivo orientar a médicos nefrólogos y no nefrólogos que asisten a pacientes con enfermedad renal crónica (ERC) en todas las etapas de la misma, en el proceso de vacunación contra el SARS-CoV-2. Como consecuencia de la situación epidemiológica y de los tiempos del proceso de elaboración de las vacunas disponibles, no se ha generado evidencia lo suficientemente potente, por lo que las recomendaciones no se acompañan del nivel de evidencia. Se fundamenta la necesidad de priorizar la vacunación en este grupo de pacientes en el mayor riesgo de adquirir la infección por SARS-CoV-2, desarrollar la enfermedad COVID-19 con mayor gravedad y presentar una mortalidad más elevada que la población general. Las recomendaciones se organizan por grupos de pacientes considerando pacientes con ERC no dialítica, diálisis y trasplante renal, y pacientes bajo tratamiento inmunosupresor.

Summary The objective of this document containing recommendations is to provide guidelines for nephrologists and non-nephrologists who assist patients with chronic kidney disease (CKD) at all stages of the disease on the vaccination process against SARS-CoV-2. As a consequence of the current epidemiological situation and the timing of the COVID-19 vaccine development -for available vaccines- there is no solid evidence, and thus, recommendations are not accompanied by the due medical proof. The need to prioritize vaccination in this group of patients is based on the increased risk of acquiring the SARS-CoV-2 infection, developing the COVID-19 disease with greater severity and presenting higher mortality rates than the general population. The recommendations are organized by groups of patients, considering patients with non-dialytic CKD, dialysis and kidney transplantation, and patients under immunosuppressive treatment.

Resumo: O objetivo deste documento de recomendações é orientar os nefrologistas e não nefrologistas que atendem pacientes com doença renal crônica (DRC) em todas as fases da doença, no processo de vacinação contra a SARS-CoV-2. Como consequência da situação epidemiológica e do momento do processo de produção das vacinas disponíveis, não foram geradas evidências suficientemente potentes, de modo que as recomendações não são acompanhadas de seu nível de evidência. A necessidade de priorizar a vacinação neste grupo de pacientes baseia-se no maior risco de adquirir a infecção pelo SARS-CoV-2, desenvolver a doença COVID-19 com maior gravidade e apresentar mortalidade superior à da população em geral. As recomendações são organizadas por grupos de pacientes, considerando pacientes com DRC não dialítica, em diálise, com transplante renal, e pacientes em tratamento imunossupressor.

A Personalized Update on IgA Nephropathy: A New Vision and New Future Challenges.

IgA nephropathy (IgAN) is the most common primary glomerulonephritis in the world among patients undergoing renal biopsy. Approximately 30% of patients with IgAN develop end-stage kidney disease 20 years after renal biopsy. It is a glomerulopathy with a very broad clinical presentation, making it difficult to stratify and treat. IgAN is characterized by dysregulation of the immune system, which causes an abnormal synthesis of IgA1 that is deglycosylated causing its mesangial deposition. IgAN pathogenesis is incompletely understood; the current multi-hit hypothesis of IgAN pathogenesis does not explain the range of glomerular inflammation and renal injury associated with mesangial IgA deposition. Although associations between IgAN and glomerular and circulating markers of complement activation are established, the mechanism of complement activation and contribution to glomerular inflammation and injury are not defined. On the other hand, the renal-gut connection can also play an important role in the pathogenesis of IgAN with possible therapeutic implications. In order to standardize the histological findings, the Oxford Classification has allowed clarifying renal lesions that confer potential risk of progression. Currently, except for the blockade of the renin-angiotensin-aldosterone system, no other therapies are available in clinical setting for the treatment of IgAN, although the range of new drugs under investigation is extensive. The incorporation in the next trials of clinical parameters such as the amount of hematuria and histological lesions may allow more personalized therapeutic approaches. To summarize, in recent years, several important efforts have taken place in the understanding of IgAN, but still, further studies are warranted to elucidate the best therapeutic strategies according to the risk to improve the prognosis of this entity.

Substitution of Oral for Intravenous Cyclophosphamide in Membranous Nephropathy.

Background: Optimal immunosuppressive treatment for membranous nephropathy is still a matter of controversy. Current recommendations include oral cyclophosphamide combined with steroids (modified Ponticelli regimen) as first-line treatment in patients who are high risk. However, concerns about the cumulative toxicity of oral cyclophosphamide persist. In the last 30 years, a protocol based on low-dose intravenous cyclophosphamide plus steroids has been used to treat membranous nephropathy in Uruguay. We aimed to assess the efficacy of this regimen to induce clinical remission in patients with membranous nephropathy. Methods: In this retrospective, observational cohort study, we analyzed the outcome of 55 patients with membranous nephropathy treated between 1990 and 2017 with a 6-month course of alternating steroids (months 1, 3, and 5) plus intravenous cyclophosphamide (single dose of 15 mg/kg on the first day of months 2, 4, and 6). Results: At 24 months, 39 (71%) patients achieved clinical response with complete remission observed in 23 patients (42%) and partial remission in 16 (29%). Median time to achieve partial and complete remission was 5.9 and 11.5 months, respectively. Absence of response was observed in 16 patients (29%), five of whom started chronic RRT after a median follow-up of 3.5 years. Clinical relapse occurred in nine of 33 (27%) patients at a median of 34 months after treatment discontinuation. Conclusions: Replacement of oral cyclophosphamide with a single intravenous pulse on months 2, 4, and 6 of the modified Ponticelli regimen can be an effective and safe alternative for treatment of membranous nephropathy. Podcast: This article contains a podcast at https://www.asn-online.org/media/podcast/K360/2020_09_24_KID0002802020.mp3.

Blood Pressure in relation to 24-Hour Urinary Sodium and Potassium Excretion in a Uruguayan Population Sample.

Many public health policies in Latin America target an optimized sodium and potassium intake. The aims of this study were to assess the sodium and potassium intake using 24-hour urinary analysis and to study their association with blood pressure in a Uruguayan population cohort using cluster analysis. A total of 149 participants (aged 20-85 years) were included in the study, and office blood pressure, anthropometric measurements, biochemical parameters in the blood, and 24-hour urine samples were obtained. The overall mean sodium and potassium excretion was 152.9 ± 57.3 mmol/day (8.9 ± 3.4 g/day of salt) and 55.4 ± 19.6 mmol/day, respectively. The average office systolic/diastolic blood pressure was 124.6 ± 16.7/79.3 ± 9.9 mmHg. Three compact spherical clusters were defined in untreated participants based on predetermined attributes, including blood pressure, age, and sodium and potassium excretion. The major characteristics of the three clusters were (1) high systolic blood pressure and moderate sodium excretion, (2) moderate systolic blood pressure and very high sodium excretion, and (3) low systolic blood pressure and low sodium excretion. Participants in cluster three had systolic blood pressure values that were 23.9 mmHg (95% confidence interval: -29.5 to -1.84) lower than those in cluster one. Participants in cluster two had blood pressure levels similar to those in cluster one (P = 0.32) and worse metabolic profiles than those in cluster one and three (P < 0.05). None of the clusters showed high blood pressure levels and high sodium excretion. No linear association was found between blood pressure and urinary sodium excretion (r < 0.14; P > 0.47). An effect of sodium and potassium intake on blood pressure levels was not found at the population level using regression or cluster analysis.

Reliable Quantification of the Potential for Equations Based on Spot Urine Samples to Estimate Population Salt Intake: Protocol for a Systematic Review and Meta-Analysis.

BACKGROUND: Methods based on spot urine samples (a single sample at one time-point) have been identified as a possible alternative approach to 24-hour urine samples for determining mean population salt intake. OBJECTIVE: The aim of this study is to identify a reliable method for estimating mean population salt intake from spot urine samples. This will be done by comparing the performance of existing equations against one other and against estimates derived from 24-hour urine samples. The effects of factors such as ethnicity, sex, age, body mass index, antihypertensive drug use, health status, and timing of spot urine collection will be explored. The capacity of spot urine samples to measure change in salt intake over time will also be determined. Finally, we aim to develop a novel equation (or equations) that performs better than existing equations to estimate mean population salt intake. METHODS: A systematic review and meta-analysis of individual participant data will be conducted. A search has been conducted to identify human studies that report salt (or sodium) excretion based upon 24-hour urine samples and spot urine samples. There were no restrictions on language, study sample size, or characteristics of the study population. MEDLINE via OvidSP (1946-present), Premedline via OvidSP, EMBASE, Global Health via OvidSP (1910-present), and the Cochrane Library were searched, and two reviewers identified eligible studies. The authors of these studies will be invited to contribute data according to a standard format. Individual participant records will be compiled and a series of analyses will be completed to: (1) compare existing equations for estimating 24-hour salt intake from spot urine samples with 24-hour urine samples, and assess the degree of bias according to key demographic and clinical characteristics; (2) assess the reliability of using spot urine samples to measure population changes in salt intake overtime; and (3) develop a novel equation that performs better than existing equations to estimate mean population salt intake. RESULTS: The search strategy identified 538 records; 100 records were obtained for review in full text and 73 have been confirmed as eligible. In addition, 68 abstracts were identified, some of which may contain data eligible for inclusion. Individual participant data will be requested from the authors of eligible studies. CONCLUSIONS: Many equations for estimating salt intake from spot urine samples have been developed and validated, although most have been studied in very specific settings. This meta-analysis of individual participant data will enable a much broader understanding of the capacity for spot urine samples to estimate population salt intake.

Prevalence and Determinants of Masked Hypertension Among Black Nigerians Compared With a Reference Population.

Hitherto, diagnosis of hypertension in sub-Saharan Africa was largely based on conventional office blood pressure (BP). Data on the prevalence of masked hypertension (MH) in this region is scarce. Among individuals with normal office BP (<140/90 mm Hg), we compared the prevalence and determinants of MH diagnosed with self-monitored home blood pressure (≥135/85 mm Hg) among 293 Nigerians with a reference population consisting of 3615 subjects enrolled in the International Database on Home Blood Pressure in Relation to Cardiovascular Outcomes. In the reference population, the prevalence of MH was 14.6% overall and 11.1% and 39.6% in untreated and treated participants, respectively. Among Nigerians, the prevalence standardized to the sex and age distribution of the reference population was similar with rates of 14.4%, 8.6%, and 34.6%, respectively. The mutually adjusted odds ratios of having MH in Nigerians were 2.34 (95% confidence interval, 1.39-3.94) for a 10-year higher age, 1.92 (1.11-3.31) and 1.70 (1.14-2.53) for 10- or 5-mm Hg increments in systolic or diastolic office BP, and 3.05 (1.08-8.55) for being on antihypertensive therapy. The corresponding estimates in the reference population were similar with odds ratios of 1.80 (1.62-2.01), 1.64 (1.45-1.87), 1.13 (1.05-1.22), and 2.84 (2.21-3.64), respectively. In conclusion, MH is as common in Nigerians as in other populations with older age and higher levels of office BP being major risk factors. A significant proportion of true hypertensive subjects therefore remains undetected based on office BP, which is particularly relevant in sub-Saharan Africa, where hypertension is now a major cause of death.

Relationship between office and home blood pressure with increasing age: The International Database of HOme blood pressure in relation to Cardiovascular Outcome (IDHOCO).

Home blood pressure (HBP) measurements are known to be lower than conventional office blood pressure (OBP) measurements. However, this difference might not be consistent across the entire age range and has not been adequately investigated. We assessed the relationship between OBP and HBP with increasing age using the International Database of HOme blood pressure in relation to Cardiovascular Outcome (IDHOCO). OBP, HBP and their difference were assessed across different decades of age. A total of 5689 untreated subjects aged 18-97 years, who had at least two OBP and HBP measurements, were included. Systolic OBP and HBP increased across older age categories (from 112 to 142 mm Hg and from 109 to 136 mm Hg, respectively), with OBP being higher than HBP by ∼7 mm Hg in subjects aged >30 years and lesser in younger subjects (P=0.001). Both diastolic OBP and HBP increased until the age of ∼50 years (from 71 to 79 mm Hg and from 66 to 76 mm Hg, respectively), with OBP being consistently higher than HBP and a trend toward a decreased OBP-HBP difference with aging (P<0.001). Determinants of a larger OBP-HBP difference were younger age, sustained hypertension, nonsmoking and negative cardiovascular disease history. These data suggest that in the general adult population, HBP is consistently lower than OBP across all the decades, but their difference might vary between age groups. Further research is needed to confirm these findings in younger and older subjects and in hypertensive individuals.

The Diurnal Profile of Central Hemodynamics in a General Uruguayan Population.

BACKGROUND: No previous population study assessed the diurnal profile of central arterial properties. METHODS: In 167 participants (mean age, 56.1 years; 63.5% women), randomly recruited in Montevideo, Uruguay, we used the oscillometric Mobil-O-Graph 24-h PWA monitor to measure peripheral and central systolic (SBP), diastolic (DBP), and pulse (PP) pressures and central hemodynamics standardized to a heart rate of 75 bpm, including aortic pulse wave velocity, systolic augmentation (first/second peak × 100), and pressure amplification (peripheral PP/central PP). RESULTS: Over 24 hours, day and night, peripheral minus central differences in SBP/DBP and in PP averaged 12.2/-1.1, 14.0/-0.7, and 9.7/0.2mm Hg and 12.6, 14.7, and 9.5mm Hg, respectively (P < 0.001 except for nighttime DBP (P = 0.38)). The central-to-peripheral ratios of SBP, DBP, and PP were 0.89, 1.00, and 0.70 unadjusted, but after accounting for anthropometric characteristics decreased to 0.74, 0.97, and 0.63, respectively, with strong influence of height for SBP and DBP and of sex for PP. From day (10-20h) to nighttime (0-6h), peripheral (-10.4/-10.5 mm Hg) and central (-6.0/-11.3mm Hg) SBP/DBP, pulse wave velocity (-0.7 m/s) and pressure amplification (-0.05) decreased (P < 0.001), whereas central PP (+5.3mm Hg) and systolic augmentation (+2.3%) increased (P < 0.001). CONCLUSIONS: The diurnal rhythm of central pressure runs in parallel with that of peripheral pressure, but the nocturnal fall in SBP is smaller centrally than peripherally. pulse wave velocity, systolic augmentation, and pressure amplification loop through the day with high pulse wave velocity and pressure amplification but low systolic augmentation in the evening and opposite trends in the morning.

Mechanisms of Salt-Sensitive Hypertension.

Hypertension and its consequences, including heart failure, stroke, and kidney disease, are responsible for substantial morbidity and mortality worldwide. Lifestyle changes, particularly sodium reduction, contribute to blood pressure control. However, not all individuals, whether normotensive or hypertensive, have the same susceptibility to the effects of salt. While a variety of approaches have been proposed to identify salt sensitive patients, there is no consensus for a definition of salt sensitivity and the precise mechanisms that explain their association are not yet fully understood. In this review we summarize the current understanding of the various pathophysiological mechanisms potentially involved in determining the salt sensitive phenotype. Genetic, neuronal, and immune alterations are reviewed. Additionally, we provide an update on the current knowledge of a new approach proposing the interstitium of the skin may act as a sodium reservoir. The role of dietary potassium on salt sensitive hypertension is also summarized.

[Severe hypokalemic rhabdomyolysis. Report of six cases]. / Rabdomiólisis por hipopotasemia severa.

Rhabdomyolysis results from acute necrosis of skeletal muscle fibers and consequent leakage of muscle constituents into the circulation. It ranges from an asymptomatic state to a severe condition associated with extreme elevations in creatine kinase and acute renal failure. Reported etiologies of rhabdomyolysis include alcohol abuse, drugs, muscle trauma and muscle overexertion. Less common causes include muscle enzyme deficiencies, electrolyte abnormalities, infectious causes, toxins and endocrine disorders. Hypokalemia is a rare cause of rhabdomyolysis. We report six patients aged 31 to 57 years (three women) with a severe hypokalemic rhabdomyolysis, secondary to chronic diarrhea in two patients, treatment with loop diuretics in one and Gitelman syndrome in three. Rhabdomyolysis may be underdiagnosed in the context of hypokalemia, because the neuromuscular symptoms can be attributed solely to the electrolyte disorder.

Estimation of Glomerular Filtration Rate Based on Serum Cystatin C versus Creatinine in a Uruguayan Population.

Background. Estimation of glomerular filtration rate (eGFR) from biomarkers has evolved and multiple equations are available to estimate renal function at bedside. Methods. In a random sample of 119 Uruguayans (54.5% women; 56.2 years (mean)), we used Bland and Altman's method and Cohen's kappa statistic to assess concordance on a continuous or categorical (eGFR < 60 versus ≥60 mL/min/1.73 m(2)) scale between eGFRcys (reference) and eGFR derived from serum creatinine according to the Modification of Diet in Renal Disease (eGFRmdrd) or the Chronic Kidney Disease Epidemiology Collaboration equations (eGFRepi) or from both serum cystatin C and creatinine (eGFRmix). Results. In all participants, eGFRmdrd, eGFRepi, and eGFRmix were, respectively, 9.7, 11.5, and 5.6 mL/min/1.73 m(2) higher (P < 0.0001) than eGFRcys. The prevalence of eGFR <60 mL/min/1.73 m(2) was the highest for eGFRcys (21.8%), intermediate for eGFRmix (11.8%), and the lowest for eGFRmdrd (5.9%) and eGFRepi (3.4%). Using eGFRcys as reference, we found only fair agreement with the equations based on creatinine (Cohen's kappa statistic 0.15 to 0.23). Conclusion. Using different equations we reached clinically significant differences in the estimation of renal function. eGFRcys provides lower estimates, resulting in higher prevalence of eGFR <60 mL/min/1.73 m(2).

Setting thresholds to varying blood pressure monitoring intervals differentially affects risk estimates associated with white-coat and masked hypertension in the population.

Outcome-driven recommendations about time intervals during which ambulatory blood pressure should be measured to diagnose white-coat or masked hypertension are lacking. We cross-classified 8237 untreated participants (mean age, 50.7 years; 48.4% women) enrolled in 12 population studies, using ≥140/≥90, ≥130/≥80, ≥135/≥85, and ≥120/≥70 mm Hg as hypertension thresholds for conventional, 24-hour, daytime, and nighttime blood pressure. White-coat hypertension was hypertension on conventional measurement with ambulatory normotension, the opposite condition being masked hypertension. Intervals used for classification of participants were daytime, nighttime, and 24 hours, first considered separately, and next combined as 24 hours plus daytime or plus nighttime, or plus both. Depending on time intervals chosen, white-coat and masked hypertension frequencies ranged from 6.3% to 12.5% and from 9.7% to 19.6%, respectively. During 91 046 person-years, 729 participants experienced a cardiovascular event. In multivariable analyses with normotension during all intervals of the day as reference, hazard ratios associated with white-coat hypertension progressively weakened considering daytime only (1.38; P=0.033), nighttime only (1.43; P=0.0074), 24 hours only (1.21; P=0.20), 24 hours plus daytime (1.24; P=0.18), 24 hours plus nighttime (1.15; P=0.39), and 24 hours plus daytime and nighttime (1.16; P=0.41). The hazard ratios comparing masked hypertension with normotension were all significant (P<0.0001), ranging from 1.76 to 2.03. In conclusion, identification of truly low-risk white-coat hypertension requires setting thresholds simultaneously to 24 hours, daytime, and nighttime blood pressure. Although any time interval suffices to diagnose masked hypertension, as proposed in current guidelines, full 24-hour recordings remain standard in clinical practice.

Quality of the blood pressure phenotype in the GEnotipo, Fenotipo y Ambiente de la hipertensión arterial en UruguaY (GEFA-HT-UY) study.

BACKGROUND: In the ongoing GEnotipo, Fenotipo y Ambiente de la HiperTensión Arterial en UruguaY (GEFA-HT-UY) study, we applied standardized epidemiological methods to determine complex phenotypes including blood pressure (BP). In this report, we present the quality control of the conventionally measured BP. METHODS: Three trained observers measured BP five times consecutively in the seated position at each of two home visits and one clinic visit according to the guidelines of the European Society of Hypertension. On 1 December 2013, 4379 single BP readings in 170 participants were available for analysis. RESULTS: Fewer BP readings than the five planned per contact occurred only at one home visit. Among observers, the frequency of identical consecutive readings for systolic or diastolic BP varied from 0 to 4.2%. The occurrence of odd readings ranged from 0.1 to 0.6%. Only 21.6% of the systolic and diastolic BP readings ended on zero (expected 20%). At home visits, there was a progressive decline in BP from the first to the fifth reading. The average of the five BP readings also decreased from the first to the second home visit (-5.63/-2.34 mmHg). CONCLUSIONS: Our study highlighted the necessity to implement a stringent quality control of the conventionally measured BP. The procedures set up in the GEFA-HT-UY study are resulting in a well-defined BP phenotype, which is consistent with that in other population studies.

Rabdomiólisis por hipopotasemia severa: Report of six cases / Severe hypokalemic rhabdomyolysis

Rhabdomyolysis results from acute necrosis of skeletal muscle fibers and consequent leakage of muscle constituents into the circulation. It ranges from an asymptomatic state to a severe condition associated with extreme elevations in creatine kinase and acute renal failure. Reported etiologies of rhabdomyolysis include alcohol abuse, drugs, muscle trauma and muscle overexertion. Less common causes include muscle enzyme deficiencies, electrolyte abnormalities, infectious causes, toxins and endocrine disorders. Hypokalemia is a rare cause of rhabdomyolysis. We report six patients aged 31 to 57 years (three women) with a severe hypokalemic rhabdomyolysis, secondary to chronic diarrhea in two patients, treatment with loop diuretics in one and Gitelman syndrome in three. Rhabdomyolysis may be underdiagnosed in the context of hypokalemia, because the neuromuscular symptoms can be attributed solely to the electrolyte disorder.

Significance of white-coat and masked hypertension in chronic kidney disease and end-stage renal disease.

Hypertension is a frequent and modifiable cardiovascular risk factor with a cyclic relationship with chronic kidney disease (CKD). The diagnosis, treatment, monitoring and control of high blood pressure are all mandatory not only in CKD but also in end-stage renal disease (ESRD). As demonstrated by studies using population and hypertensive patients, white-coat hypertension (WCHT) and masked hypertension (MHT) carry a particular degree of risk. The advantages of ambulatory techniques in the management and prognostic stratification of patients with CKD and ESRD have also been recognized. However, most of the evidence underlines the importance of nocturnal hypertension and neglects WCHT and MHT. The absence of specific reports involving untreated and treated patients hinders the ability to significantly discriminate WCHT from the white-coat effect and MHT from masked uncontrolled hypertension. The heterogeneous definitions that are used add additional difficulty in translating experimental evidence into clinical practice. Reaching a consensus in definitions is mandatory for designing future research. Cross-sectional studies underscore the frequency of misdiagnosis, potentially leading to undertreatment (MHT) and overtreatment (WCHT) in renal disease. The divergent prevalence of WCHT and MHT reported in CKD could be related to the diverse definitions of hypertension and the heterogeneity of the pathologies pooled under the CKD definition. Even in the absence of randomized clinical trials specifically addressing this issue, the scarce longitudinal studies confirm that WCHT carries a risk close to that of sustained normotension, whereas MHT is associated with a risk close or identical to that of sustained hypertension.