Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 698
Filtrar
1.
Am J Physiol Renal Physiol ; 322(2): F225-F244, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35001663

RESUMO

The renal response to acute hyperkalemia is mediated by increased K+ secretion within the connecting tubule (CNT), flux that is modulated by tubular effects (e.g., aldosterone) in conjunction with increased luminal flow. There is ample evidence that peritubular K+ blunts Na+ reabsorption in the proximal tubule, thick ascending Henle limb, and distal convoluted tubule (DCT). Although any such reduction may augment CNT delivery, the relative contribution of each is uncertain. The kidney model of this laboratory was recently advanced with representation of the cortical labyrinth and medullary ray. Model tubules capture the impact of hyperkalemia to blunt Na+ reabsorption within each upstream segment. However, this forces the question of the extent to which increased Na+ delivery is transmitted past the macula densa and its tubuloglomerular feedback (TGF) signal. Beyond increasing macula densa Na+ delivery, peritubular K+ is predicted to raise cytosolic Cl- and depolarize macula densa cells, which may also activate TGF. Thus, although the upstream reduction in Na+ transport may be larger, it appears that the DCT effect is critical to increasing CNT delivery. Beyond the flow effect, hyperkalemia reduces ammoniagenesis and reduced ammoniagenesis enhances K+ excretion. What this model provides is a possible mechanism. When cortical [Formula: see text] is taken up via peritubular Na+-K+([Formula: see text])-ATPase, it acidifies principal cells. Consequently, reduced ammoniagenesis increases principal cell pH, thereby increasing conductance of both the epithelial Na+ channel and renal outer medullary K+ channel, enhancing K+ excretion. In this model, the effect of aldosterone on principal cells, diminished DCT Na+ reabsorption, and reduced ammoniagenesis all provide relatively equal and additive contributions to renal K+ excretion.NEW & NOTEWORTHY Hyperkalemia blunts Na+ reabsorption along the nephron, and increased CNT Na+ delivery facilitates K+ secretion. The model suggests that tubuloglomerular feedback limits transmission of proximal effects past the macula densa, so that it is DCT transport that is critical. Hyperkalemia also reduces PCT ammoniagenesis, which enhances K+ excretion. The model suggests a mechanism, namely, that reduced cortical ammonia impacts CNT transport by raising cell pH and thus increasing both ENaC and ROMK conductance.


Assuntos
Amônia/metabolismo , Hiperpotassemia/metabolismo , Rim/metabolismo , Modelos Biológicos , Potássio/sangue , Eliminação Renal , Reabsorção Renal , Sódio/metabolismo , Animais , Canais Epiteliais de Sódio/metabolismo , Retroalimentação Fisiológica , Concentração de Íons de Hidrogênio , Hiperpotassemia/sangue , Hiperpotassemia/fisiopatologia , Rim/fisiopatologia , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Ratos
2.
Am J Emerg Med ; 51: 401-408, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34602330

RESUMO

OBJECTIVE: Chon et al. suggested a high prevalence of severe hyperkalemia (serum potassium ≥ 6.0 mEq/L with electrocardiographic [ECG] changes) among patients with symptomatic or extreme bradycardia. Despite the urgent need to detect and treat severe hyperkalemia, serum potassium result may be available too late and is often spuriously high. Meanwhile, the traditional, descriptive ECG findings of severe hyperkalemia have shown unsatisfactory diagnostic powers. To overcome these diagnostic problems, they outlined the following quantitative rules to facilitate its early detection: Maximum precordial T wave ≥ 8.5 mV (2), atrial fibrillation/junctional bradycardia (1), heart rate (HR) ≤ 42/min (1) with (original rule)/without (ECG-only rule) diltiazem medication (2), and diabetes mellitus (1). Here we report on our external validation of these rules and the resulting updates. METHODS: This retrospective, cross-sectional study included all adults with symptomatic (HR ≤ 50/min with syncope/pre-syncope/dizziness, altered mentality, chest pain, dyspnea, general weakness, oliguria, or shock) or extreme (HR ≤ 40/min) bradycardia who visited a university emergency department from 2014 to 2019. After validating the abovementioned rules externally, we selected risk factors of severe hyperkalemia among the ECG findings and easy-to-assess clinical variables by multiple logistic regression analysis. After modelling the updated 'ECG-only' and 'ECG-plus' indices, we internally validated the better of the two by bootstrapping with 1000 iterations. RESULTS: Among 455 symptomatic/extreme bradycardia cases (70.3 ± 13.1 years; 213 females [46.8%]), 70 (15.4%) had severe hyperkalemia. The previous ECG-only rule showed a c-statistic of 0.765 (95% CI: 0.706-0.825), Hosmer-Lemeshow test of p < 0.001, and a calibration slope of 0.719 (95% CI: 0.401-1.04). On updating, the ECG-plus index summing junctional bradycardia/atrial fibrillation (1), maximum precordial T wave≥8.0 mV (2), general weakness as the chief complaint (2), oxygen demand (1), and dialysis (2) outperformed the ECG-only index (c-statistic, 0.832; 95% CI, 0.785-0.880 vs. 0.764; 95% CI, 0.700-0.828; p = 0.011). On bootstrapping, the c-statistic was 0.832 (95% CI: 0.786-0.878). For scores ≥ 3 (positive likelihood ratio ≥ 5.0), the sensitivity and specificity were 0.514 and 0.901, respectively. For scores ≤ 1, negative likelihood ratio was ≤0.2. CONCLUSIONS: Previous rules showed less satisfactory calibration but fair discrimination to detect severe hyperkalemia in patients with symptomatic or extreme bradycardia. We propose the ECG-plus index as the optimum tool to facilitate its early detection.


Assuntos
Bradicardia/complicações , Diagnóstico Precoce , Eletrocardiografia/métodos , Hiperpotassemia/diagnóstico , Hiperpotassemia/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Bradicardia/epidemiologia , Estudos Transversais , Feminino , Humanos , Hiperpotassemia/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Sinais Vitais
3.
Ther Apher Dial ; 26(1): 3-14, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34378859

RESUMO

Potassium is a major intracellular cation in the body, regulating membrane potential of excitable cells, such as cardiomyocytes and skeletal muscle cells. Because the kidney plays a critical role in controlling potassium balance, the elevation in serum potassium levels is one of the most common complications in patients with maintenance hemodialysis (MHD). In addition to reduced renal potassium excretion, the alteration in body potassium distribution owing to comorbid conditions may also contribute to dyskalemia. Besides potassium elimination through hemodialysis in MHD patients, accumulating data indicate the potential importance of extra-renal elimination involving the gastrointestinal system, which can be affected by the inhibitors of the renin-angiotensin-aldosterone system. In this article, the literature on potassium physiology in MHD patients is reviewed with an emphasis on the changes from individuals with normal kidney function. This article also summarizes the findings of recent studies on dietary control, dialysate prescription, and pharmacological therapy.


Assuntos
Hiperpotassemia/fisiopatologia , Hiperpotassemia/terapia , Diálise Renal/métodos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/terapia , Humanos , Hiperpotassemia/complicações
4.
J Manag Care Spec Pharm ; 27(10): 1403-1415, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34595956

RESUMO

BACKGROUND: Patients with advanced chronic kidney disease (CKD) are at high risk for dyskalemias, which may induce arrhythmias that require immediate emergent or hospital care. The association of dyskalemias with short-term hospital/emergency room (ER) visits in advanced CKD is understudied. OBJECTIVE: To assess the association of dyskalemias with short-term hospital/ER visits in an advanced CKD population. METHODS: From among 102,477 US veterans transitioning to dialysis from 2007 to 2015, we identified 21,366 patients with 2 predialysis outpatient eGFR < 30 ml/min/1.73m2 90-365 days apart (with the second eGFR serving as the index date) and at least 1 potassium (K) in the baseline period (1 year before index) and 1 outpatient K (oK) in the follow-up (1 year after the index but before dialysis initiation). We examined the association of time-varying hypokalemia (K < 3.5 mEq/L) and hyperkalemia (K > 5.5 mEq/L) vs referent (3.5-5.5 mEq/L) with separate hospital and ER visits within 2 calendar days following each oK value over the 1-year follow-up period from the index. We used generalized estimating equations with binary distribution and logit link to model the exposure-outcome relationship adjusted for various confounders. We conducted various subgroup and sensitivity analyses to test the robustness of our results. RESULTS: Over the 1-year follow-up, 125,266 oK measurements were observed, of which 6.8% and 3.7% were classified as hyper- and hypokalemia, respectively. In the multivariable-adjusted model, hyperkalemia (adjusted odds ratio [aOR] = 2.04; 95% CI = 1.88-2.21) and hypokalemia (aOR = 1.66; 95% CI = 1.48-1.86) were associated with significantly higher odds of hospital visits. Similarly, hyperkalemia (aOR = 1.83; 95% CI = 1.65-2.03) and hypokalemia (aOR = 1.24; 95% CI = 1.07-1.44) were associated with significantly higher odds of ER visits. Results were robust to subgroups and sensitivity analyses. CONCLUSIONS: In patients with advanced CKD, dyskalemias are associated with higher risk of hospital/ER visits. Interventions targeted at lowering the risk of dyskalemias might help in reducing the health care utilization and associated economic burden among patients with advanced CKD experiencing dyskalemias. DISCLOSURES: This study was supported by grant 5U01DK102163 from the National Institute of Health (NIH) to Kamyar Kalantar-Zadeh and Csaba P. Kovesdy and by resources from the US Department of Veterans Affairs. The data reported here have been supplied in part by the United States Renal Data System (USRDS). Support for VA/CMS data were provided by the Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, Health Services Research and Development, VA Information Resource Center (project numbers SDR 02-237 and 98-004). Opinions expressed in this article are those of the authors and do not necessarily represent the opinion of the Department of Veterans Affairs or the funding institution. Kovesdy has received honoraria from Akebia, Ardelyx, Astra Zeneca, Bayer, Boehringer-Ingelheim, Cara Therapeutics, Reata, and Tricida unrelated to this study. Kalantar-Zadeh has received honoraria and/or support from Abbott, Abbvie, ACI Clinical (Cara Therapeutics), Akebia, Alexion, Amgen, American Society of Nephrology, Astra-Zeneca, Aveo, BBraun, Chugai, Cytokinetics, Daiichi, DaVita, Fresenius, Genentech, Haymarket Media, Hofstra Medical School, International Federation of Kidney Foundations, International Society of Hemodialysis, International Society of Renal Nutrition & Metabolism, Japanese Society of Dialysis Therapy, Hospira, Kabi, Keryx, Kissei, Novartis, OPKO, National Institutes of Health, National Kidney Foundations, Pfizer, Regulus, Relypsa, Resverlogix, Dr Schaer, Sandoz, Sanofi, Shire, Veterans Affairs, Vifor, UpToDate, and ZS-Pharma, unrelated to this study. Gatwood has received research support from AstraZeneca, Merck & Co., and GlaxoSmithKline unrelated to this study. Obi has received research support from Relypsa/Vifor Pharma Inc. The remaining authors declare that they have no relevant financial interests.


Assuntos
Custos de Cuidados de Saúde , Hiperpotassemia/fisiopatologia , Aceitação pelo Paciente de Cuidados de Saúde , Insuficiência Renal Crônica/patologia , Idoso , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos
6.
Drugs ; 81(13): 1467-1489, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34313978

RESUMO

Despite recent therapeutic advances, chronic kidney disease (CKD) is one of the fastest growing global causes of death. This illustrates limitations of current therapeutic approaches and, potentially, unidentified knowledge gaps. For decades, renin-angiotensin-aldosterone system (RAAS) blockers have been the mainstay of therapy for CKD. However, they favor the development of hyperkalemia, which is already common in CKD patients due to the CKD-associated decrease in urinary potassium (K+) excretion and metabolic acidosis. Hyperkalemia may itself be life-threatening as it may trigger potentially lethal arrhythmia, and additionally may limit the prescription of RAAS blockers and lead to low-K+ diets associated to low dietary fiber intake. Indeed, hyperkalemia is associated with adverse kidney, cardiovascular, and survival outcomes. Recently, novel kidney protective therapies, ranging from sodium/glucose cotransporter 2 (SGLT2) inhibitors to new mineralocorticoid receptor antagonists have shown efficacy in clinical trials. Herein, we review K+ pathophysiology and the clinical impact and management of hyperkalemia considering these developments and the availability of the novel K+ binders patiromer and sodium zirconium cyclosilicate, recent results from clinical trials targeting metabolic acidosis (sodium bicarbonate, veverimer), and an increasing understanding of the role of the gut microbiota in health and disease.


Assuntos
Hiperpotassemia/epidemiologia , Hiperpotassemia/fisiopatologia , Insuficiência Renal Crônica/epidemiologia , Humanos , Hiperpotassemia/prevenção & controle , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Gravidade do Paciente , Polímeros/uso terapêutico , Sistema Renina-Angiotensina/fisiologia , Silicatos/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
7.
J Pediatr Endocrinol Metab ; 34(9): 1131-1137, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34192833

RESUMO

OBJECTIVES: Although new-born screening (NBS) for classical congenital adrenal hyperplasia (C-CAH) has been available for decades, it is not widely implemented. We assessed the usefulness of introducing NBS for C-CAH, by analyzing presenting status of infants with C-CAH, over the past two decades, in Sri Lanka. METHODS: This retrospective clinic-based study, from the largest tertiary children's hospital in Sri Lanka, analyzed initial presenting features of children with C-CAH from 1999 to 2018, in the absence of NBS for CAH, and included gender-based comparisons. RESULTS: Features suggestive of impending adrenal-crisis were seen at initial presentation in >80 % (dehydration 70%, hyponatremia 65%, hyperkalemia 47%, vomiting 45%, hypoglycemia 22%, collapse 20%). Hyperpigmentation was seen in 78%, and consanguinity in 27%. There were fewer affected males (n = 12) compared to females (n = 28). Most girls (96%) had virilized genitalia, and 16 faced uncertainty about gender at birth. Median age at diagnosis was 20 days. More than 70% of children had SW-CAH (males = 9 and females = 20). There were fewer males with SW-CAH, and all had features of impending adrenal crisis, including severe hyponatremia in 50%, while 62% of girls also developed hyponatremia and 33% had hyperkalemia, prior to treatment. Treatment of SW-CAH was initiated at a median age of 30 days in boys, and 10 days of age in girls. CONCLUSION: Many boys and girls with C-CAH from Sri Lanka presented late with impending adrenal crisis. Males were diagnosed later, and some possibly succumbed to C-CAH undiagnosed. These findings support including CAH in NBS programs to avert preventable childhood morbidity and mortality.


Assuntos
Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperpotassemia/fisiopatologia , Hiperpigmentação/fisiopatologia , Hiponatremia/fisiopatologia , Vômito/fisiopatologia , Adolescente , Hiperplasia Suprarrenal Congênita/epidemiologia , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Triagem Neonatal , Prognóstico , Estudos Retrospectivos , Sri Lanka/epidemiologia , Adulto Jovem
8.
Intern Emerg Med ; 16(7): 1787-1792, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33544373

RESUMO

Although hyperkalemia (HK) is often associated with adverse clinical outcomes in renal patients, few studies are available in the setting of kidney transplantation. Therefore, we evaluated prevalence and clinical correlates of HK in stable kidney transplant recipients (KTRs) on standard of care immunosuppressive therapy. We studied 160 stable KTRs (post-transplant vintage 46.6 ± 16.6 months), most of whom (96.2%) on calcineurin inhibitor (CNI)-based immunosuppressive therapy. HK was defined as plasma potassium levels above 5 mEq/L, confirmed in two consecutive samples. Office blood pressure was measured, and renal graft function was expressed by estimated glomerular filtration rate (eGFR), calculated according to the CKD-EPI formula. HK prevalence was 8.8%, and plasma K above 5.5 mEq/L was found in 2.5% of all KTRs. In the univariate logistic regression analysis HK was significantly associated with serum urea concentration (OR 1.03, 95% CI 1.01-1.05 for each 1 mg/dL increase), tCO2 (OR 0.77, 95% CI 0.66-0.90 for each 1 mmol/L increase), the presence of arterial hypertension (OR 4.01, 95% CI 1.3-12.64), the use of RAAS inhibitors (OR 5.26, 95% CI 1.6-17.7), and eGFR less than 30 ml/min/1.73 m2 (OR 7.51, 95% CI 2.37-23.77). By multivariable backward stepwise regression analysis, the presence of metabolic acidosis (OR 0.83, 95% CI 0.69-0.99, P = 0.04), arterial hypertension (OR 4.65 95% CI 1.01-17.46 P = 0.03), and to be administered RAAS inhibitors (OR 6.11, 95% CI 1.03-25.96 P = 0.03) remained significantly associated with HK. We conclude that in stable KTRs the prevalence of HK is about 9%, slightly lower than previously reported. Moreover, it is not associated with eGFR, but with metabolic acidosis, arterial hypertension, and the use of RAAS inhibitors.


Assuntos
Hiperpotassemia/epidemiologia , Transplante de Rim , Inibidores de Calcineurina/administração & dosagem , Estudos Transversais , Feminino , Humanos , Hiperpotassemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
10.
Saudi J Kidney Dis Transpl ; 31(5): 1134-1139, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33229781

RESUMO

Gordon syndrome involves hyperkalemia, acidosis, and severe hypertension (HTN) with hypercalciuria, low renin and aldosterone levels. It is commonly observed in children and adolescents. Such patients respond successfully to sodium restriction and thiazide diuretics. In this article, we present three cases of metabolic acidosis, hyperkalemia, and renal unresponsiveness to aldosterone (MeHandRU Syndrome). All three patients did not have HTN or hypercalciuria and demonstrated normal renin and aldosterone levels. These patients did not respond to thiazide-type diuretic therapy and salt restriction. Two males (aged 55- and 62-year) and a female patient (aged 68-year) presented to the clinic with unexplained hyperkalemia (5.9 mEq/L, 5.9 mEq/L and 6.2 mEq/L, respectively). On physical examination, blood pressure (BP) was found to be normal (<140/90 mm Hg). Over the counter potassium supplement, nonsteroidal anti-inflammatory drugs, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, potassium sparing diuretic use, as well as hyporeninemic hypoaldosteronism states such as diabetes mellitus were excluded. Plasma renin and aldosterone levels were normal. All three patients had low transtubular potassium gradient, despite high serum potassium levels. None of the patients reported a family history of hyperkalemia or kidney failure. All failed to demonstrate a response to hydrochlorothiazide and salt restriction. After careful consideration, strict low potassium diet (<2 g/day) was initiated in consultation with the dietician. Diuretic therapy was discontinued while BP remained within normal range (<140/90 mm Hg). At eight weeks, all three patients demonstrated normalization of potassium and correction of acidosis. At follow-up of six months, all patients are maintaining a normal potassium level. We suggest that potassium restriction can be successful in patients presenting with MeHandRU syndrome.


Assuntos
Acidose/dietoterapia , Hiperpotassemia/dietoterapia , Pseudo-Hipoaldosteronismo/dietoterapia , Acidose/diagnóstico , Acidose/fisiopatologia , Idoso , Aldosterona/sangue , Feminino , Humanos , Hiperpotassemia/diagnóstico , Hiperpotassemia/fisiopatologia , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Potássio/sangue , Pseudo-Hipoaldosteronismo/diagnóstico , Pseudo-Hipoaldosteronismo/fisiopatologia
11.
Methodist Debakey Cardiovasc J ; 16(3): 241-244, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133361

RESUMO

BRASH syndrome is characterized by bradycardia, renal failure, use of an atrioventricular nodal blocker (AVNB), shock, and hyperkalemia. These symptoms represent an ongoing vicious cycle in a patient with a low glomerular filtration rate taking an AVNB. Decreased clearance of the medication and hyperkalemia associated with renal failure synergize to cause bradycardia and hypoperfusion. This reaction causes renal function to worsen, thereby perpetuating the cycle of BRASH syndrome.


Assuntos
Anti-Hipertensivos/efeitos adversos , Nó Atrioventricular/efeitos dos fármacos , Bradicardia/induzido quimicamente , Diltiazem/efeitos adversos , Hiperpotassemia/etiologia , Insuficiência Renal Crônica/complicações , Nó Atrioventricular/fisiopatologia , Bradicardia/diagnóstico , Bradicardia/fisiopatologia , Bradicardia/terapia , Feminino , Taxa de Filtração Glomerular , Humanos , Hiperpotassemia/diagnóstico , Hiperpotassemia/fisiopatologia , Hiperpotassemia/terapia , Rim/fisiopatologia , Pessoa de Meia-Idade , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/terapia , Síndrome , Resultado do Tratamento
12.
Prim Care ; 47(4): 555-569, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33121628

RESUMO

Volume and electrolyte evaluation and management is seen frequently in primary care practices. Some of the most common abnormalities encountered in outpatient practices are prerenal azotemia, dysnatremias, and altered potassium levels. Perturbations in volume or electrolyte concentrations can lead to serious organ dysfunction as well as hemodynamic collapse. This review focuses on the maintenance and regulation of intravascular volume and electrolytes, specifically sodium and potassium.


Assuntos
Azotemia/fisiopatologia , Rim/fisiologia , Desequilíbrio Hidroeletrolítico/fisiopatologia , Desequilíbrio Hidroeletrolítico/terapia , Nitrogênio da Ureia Sanguínea , Água Corporal/fisiologia , Creatinina/sangue , Humanos , Hiperpotassemia/fisiopatologia , Hiperpotassemia/terapia , Hipernatremia/fisiopatologia , Hipernatremia/terapia , Hipopotassemia/fisiopatologia , Hipopotassemia/terapia , Hiponatremia/fisiopatologia , Hiponatremia/terapia , Atenção Primária à Saúde
13.
Rev Cardiovasc Med ; 21(2): 241-252, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32706212

RESUMO

Hyperkalemia in heart failure is a condition that can occur with relative frequency because it is related to pathophysiological aspects of the disease, and favored by drugs that form the basis of chronic cardiac failure therapy. Often, associated comorbidities, such as kidney failure or diabetes mellitus can further adversely affect potassium levels. Hyperkalemia can result in acute and even severe clinical manifestations that put patients at risk. On the other hand, the finding of hyperkalemia in a chronic context can lead to a reduction in dosages or to suspension of drugs such as angiotensin-converting enzymes inhibitor, angiotensin receptor blocker, angiotensin receptor neprilysin inhibitor, and mineralcorticoid receptor antagonist, first line in the treatment of the disease, with negative effects in prognostic terms. Therapies for the correction of hyperkalemia have so far mainly concerned the treatment of acute clinical pictures. Newly developed molecules, such as patiromer or sodium zirconium cyclosilicate, now open new prospectives in the long-term management of hyperkalemia, and allow us to glimpse the possibility of a better titration of the cardinal drugs for heart failure, with consequent positive effects on patient prognosis. The aim of this review is to focus on the problem of hyperkalemia in the setting of heart failure, with particular regard to its incidence, its prognostic role, and the underlining pathophysiological mechanisms. The review also provides an overview of therapeutic strategies for correcting hyperkalemia in acute and chronic conditions, with a focus on the new potassium binders that promise to improve management of heart failure.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Quelantes/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Hiperpotassemia/tratamento farmacológico , Potássio/sangue , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Animais , Biomarcadores/sangue , Fármacos Cardiovasculares/efeitos adversos , Quelantes/efeitos adversos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Hiperpotassemia/sangue , Hiperpotassemia/epidemiologia , Hiperpotassemia/fisiopatologia , Incidência , Sistema Renina-Angiotensina/efeitos dos fármacos , Resultado do Tratamento , Regulação para Cima
14.
Saudi J Kidney Dis Transpl ; 31(2): 524-527, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32394928

RESUMO

Hyperkalemia is one of the dangerous complications of renal impairment (acute kidney injury or chronic kidney disease). Hyperkalemia may present with the electrocardiogram (ECG) changes as nonspecific repolarization abnormalities. Here, we report a case of AKI with hyperkalemia and the Brugada pattern of ECG, which reverted to normal after effective management of hyperkalemia. A 55-year-old male reported to the Emergency Department of National Academy of Medical Sciences (Bir Hospital) with injuries in his lower limbs and spine after he had met an accident two days back. He also had decreased urine output for the last one day. On physical examination, he had injuries in the spine and lower limbs. His laboratory investigations showed impaired renal function parameters with serum sodium 130 mEq/L and serum potassium of 7.3 mEq/L. His ECG was consistent with Brugada pattern. Patient was treated with 10% calcium gluconate, insulin and dextrose, salbutamol nebulization, and sodium polystyrene sulfonate till hemodialysis was initiated. Hyperkalemia and acidosis can manifest with the Brugada pattern in ECG. Thus, a careful evaluation of hyperkalemia and its treatment must be instituted in such an ECG pattern.


Assuntos
Injúria Renal Aguda/terapia , Arritmias Cardíacas/diagnóstico , Síndrome de Brugada/diagnóstico , Eletrocardiografia , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca , Hiperpotassemia/diagnóstico , Rabdomiólise/diagnóstico , Potenciais de Ação , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/fisiopatologia , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/fisiopatologia , Síndrome de Brugada/fisiopatologia , Diagnóstico Diferencial , Humanos , Hiperpotassemia/etiologia , Hiperpotassemia/fisiopatologia , Hiperpotassemia/terapia , Masculino , Pessoa de Meia-Idade , Nepal , Valor Preditivo dos Testes , Rabdomiólise/complicações , Rabdomiólise/fisiopatologia , Rabdomiólise/terapia
15.
Am J Nurs ; 120(6): 58-66, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32443130

RESUMO

In this article, the second in a new series designed to improve acute care nurses' understanding of laboratory abnormalities, the author continues her discussion of important values in the basic metabolic panel (see Back to Basics, January, for a discussion of sodium and fluid balance). Here she addresses the electrolytes potassium and chloride as well as blood urea nitrogen and creatinine, four values that are best considered together because they both reflect and impact renal function as well as acid-base homeostasis. Important etiology, clinical manifestations, and treatment concerns are also presented. Three case studies are used to integrate select laboratory diagnostic tests with history and physical examination findings, allowing nurses to develop a thorough, focused plan of care for electrolyte abnormalities and kidney disorders commonly encountered in the medical-surgical setting.


Assuntos
Técnicas de Laboratório Clínico/métodos , Idoso , Idoso de 80 Anos ou mais , Nitrogênio da Ureia Sanguínea , Cloretos/análise , Cloretos/sangue , Técnicas de Laboratório Clínico/tendências , Creatinina/análise , Creatinina/sangue , Feminino , Humanos , Hiperpotassemia/sangue , Hiperpotassemia/etiologia , Hiperpotassemia/fisiopatologia , Hipopotassemia/sangue , Hipopotassemia/etiologia , Hipopotassemia/fisiopatologia , Masculino , Potássio/análise , Potássio/sangue
16.
J Am Heart Assoc ; 9(7): e014996, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32208832

RESUMO

Background Angiotensin II stimulates epithelial Na+ channel (ENaC) by aldosterone-independent mechanism. We now test the effect of angiotensin II on ENaC in the distal convoluted tubule (DCT) and cortical collecting duct (CCD) of wild-type (WT) and kidney-specific mineralocorticoid receptor knockout mice (KS-MR-KO). Methods and Results We used electrophysiological, immunoblotting and renal-clearance methods to examine the effect of angiotensin II on ENaC in KS-MR-KO and wild-type mice. High K+ intake stimulated ENaC in the late DCT/early connecting tubule (DCT2/CNT) and in the CCD whereas low sodium intake stimulated ENaC in the CCD but not in the DCT2/CNT. The deletion of MR abolished the stimulatory effect of high K+ and low sodium intake on ENaC, partially inhibited ENaC in DCT2/CNT but almost abolished ENaC activity in the CCD. Application of losartan inhibited ENaC only in DCT2/CNT of both wild-type and KS-MR-KO mice but not in the CCD. Angiotensin II infusion for 3 days has a larger stimulatory effect on ENaC in the DCT2/CNT than in the CCD. Three lines of evidence indicate that angiotensin II can stimulate ENaC by MR-independent mechanism: (1) angiotensin II perfusion augmented ENaC expression in KS-MR-KO mice; (2) angiotensin II stimulated ENaC in the DCT2/CNT but to a lesser degree in the CCD in KS-MR-KO mice; (3) angiotensin II infusion augmented benzamil-induced natriuresis, increased the renal K+ excretion and corrected hyperkalemia of KS-MR-KO mice. Conclusions Angiotensin II-induced stimulation of ENaC occurs mainly in the DCT2/CNT and to a lesser degree in the CCD and MR plays a dominant role in determining ENaC activity in the CCD but to a lesser degree in the DCT2/CNT.


Assuntos
Angiotensina II/farmacologia , Canais Epiteliais de Sódio/metabolismo , Túbulos Renais Coletores/efeitos dos fármacos , Túbulos Renais Distais/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/agonistas , Receptores de Mineralocorticoides/deficiência , Animais , Hiperpotassemia/tratamento farmacológico , Hiperpotassemia/genética , Hiperpotassemia/metabolismo , Hiperpotassemia/fisiopatologia , Túbulos Renais Coletores/metabolismo , Túbulos Renais Coletores/fisiopatologia , Túbulos Renais Distais/metabolismo , Túbulos Renais Distais/fisiopatologia , Potenciais da Membrana , Camundongos Knockout , Natriurese/efeitos dos fármacos , Potássio/urina , Receptor Tipo 1 de Angiotensina/metabolismo , Receptores de Mineralocorticoides/genética , Eliminação Renal/efeitos dos fármacos
17.
Rheumatol Int ; 40(11): 1895-1901, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32166438

RESUMO

Renal tubular acidosis (RTA) is a normal anion gap metabolic acidosis that manifests with insufficiency of hydrogen ion excretion or bicarbonate (HCO3) reuptake as a result of renal tubular dysfunction independent of glomerular filtration rate. Hypokalemic RTA subtypes co-existing with autoimmune diseases particularly appear in Sjogren's syndrome, but rarely in systemic lupus erythematosus (SLE). Type 4 RTA associated with hyperkalemia is very rare during the course of SLE and hence has been scarcely reported in the literature. Here, we report a 42-year-old patient for whom regular follow-up was ongoing due to class IV lupus nephritis when she developed hyperkalemia. The patient had normal anion gap hyperkalemic metabolic acidosis and her urine pH was 5.5. Type 4 RTA was considered and, therefore, tests for renin and aldosterone levels were requested, which revealed that renin was suppressed and aldosterone was decreased. Upon diagnosis of SLE-associated type 4 RTA, short-term oral HCO3 and fludrocortisone were initiated. Potassium (K) and HCO3 levels improved at day 15 of therapy. In this review, we analyzed our case along with five other reports (a total of seven cases) of SLE-associated type 4 RTA we identified through a literature search. We wanted to highlight RTA for differential diagnosis of hyperkalemia emerging during SLE/lupus nephritis and we also discussed possible underlying mechanisms.


Assuntos
Hiperpotassemia/metabolismo , Hipoaldosteronismo/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Nefrite Lúpica/metabolismo , Acidose/complicações , Acidose/tratamento farmacológico , Acidose/metabolismo , Acidose/fisiopatologia , Adulto , Aldosterona/metabolismo , Anti-Inflamatórios/uso terapêutico , Bicarbonatos/uso terapêutico , Soluções Tampão , Feminino , Fludrocortisona/uso terapêutico , Humanos , Hiperpotassemia/complicações , Hiperpotassemia/tratamento farmacológico , Hiperpotassemia/fisiopatologia , Hipoaldosteronismo/complicações , Hipoaldosteronismo/tratamento farmacológico , Hipoaldosteronismo/fisiopatologia , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/fisiopatologia , Nefrite Lúpica/complicações , Nefrite Lúpica/fisiopatologia , Renina/metabolismo
19.
Intern Emerg Med ; 15(1): 23-31, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625077

RESUMO

Addison disease is due to the destruction or dysfunction of the entire adrenal cortex. Nowadays, the causes of adrenal insufficiency are autoimmune disease for 70-90% and tuberculosis for 7-20%. Many typical signs and symptoms, such as hyponatremia, hyperkalaemia, or renal insufficiency can represent the reasons for a nephrology consultation, especially in conditions of urgency, and they can easily be confused with other causes. Moreover, the fact that in a short time range we have diagnosed the three cases described as a guide in this review, has aroused our attention as nephrologists on a disease in which we have probably already encountered but without recognizing it. The blood tests showed in all three patients severe electrolyte disorders and acute renal failure which will be discussed in their physiopathogenetic mechanisms. In a peculiar way, these alterations were not controlled with repolarizing solutions, fluid replacement and increased volemia, but only after steroid administration. In conclusion, in this review all the known pathogenic mechanisms causing disorders of nephrological interest in adrenal insufficiency are discussed.


Assuntos
Doença de Addison/complicações , Insuficiência Renal Crônica/etiologia , Doença de Addison/fisiopatologia , Adulto , Humanos , Hipercalcemia/etiologia , Hipercalcemia/fisiopatologia , Hiperpotassemia/etiologia , Hiperpotassemia/fisiopatologia , Hiponatremia/etiologia , Hiponatremia/fisiopatologia , Rim/lesões , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Rabdomiólise/etiologia , Rabdomiólise/fisiopatologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA