The Different Paths That Lead to Hypotonic Hyponatremia, and a Safe Approach to Treatment.

A knowledge gap may exist when attempting to identify the pathogenetic mechanisms resulting in the syndrome of inappropriate antidiuretic hormone (SIADH) or hypotonic hyponatremia. Ectopic secretion of antidiuretic hormone [ADH] is the classic cause of SIADH. But another form of inappropriate secretion of ADH occurs when interleukin 6 is activated.

Successful treatment of unusual life-threatening complications of idiopathic edema.

Idiopathic edema (IE) is a disease that occurs predominantly in women. It is characterized by increasing weight gain of >1.4 kg from morning to night, increasing edema, increasing truncal and abdominal girth with bloating when assuming an upright position and nocturia that is unrelated to menses.

Haptoglobin-Related Protein without Signal Peptide as Biomarker of Renal Salt Wasting in Hyponatremia, Hyponatremia-Related Diseases and as New Syndrome in Alzheimer's Disease.

The application of pathophysiologic tenets has created significant changes in our approach to hyponatremia and hyponatremia-related conditions. This new approach incorporated the determination of fractional excretion (FE) of urate before and after the correction of hyponatremia and the response to isotonic saline infusion to differentiate the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) from renal salt wasting (RSW). FEurate simplified the identification of the different causes of hyponatremia, especially the diagnosis of a reset osmostat and Addison's disease.

New Approach to Hyponatremia: High Prevalence of Cerebral/Renal Salt Wasting, Identification of Natriuretic Protein That Causes Salt Wasting.

Our understanding of hyponatremic conditions has undergone major alterations. There is a tendency to treat all patients with hyponatremia because of common subtle symptoms that include unsteady gait that lead to increased falls and bone fractures and can progress to mental confusion, irritability, seizures, coma and even death. We describe a new approach that is superior to the ineffectual volume approach.

Pathophysiologic approach to understanding and successfully treating idiopathic edema: Unappreciated importance of nocturia.

Idiopathic edema (IE), a disorder of females, is characterized by edema and weight gains exceeding 1.4 kg while assuming an upright position followed by nocturia and returning to a non-edematous baseline weight in the morning. There is no successful treatment of IE and the importance of nocturia needs to be emphasized.

Identification of a Novel Natriuretic Protein in Patients With Cerebral-Renal Salt Wasting-Implications for Enhanced Diagnosis.

Background: The most vexing problem in hyponatremic conditions is to differentiate the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) from cerebral/renal salt wasting (C-RSW). Both have identical clinical parameters but diametrically opposite therapeutic goals of water- restricting water-logged patients with SIADH or administering salt and water to dehydrated patients with C-RSW. While C-RSW is considered a rare condition, the report of a high prevalence of C-RSW in the general hospital wards creates an urgency to differentiate one syndrome from the other on first encounter.

COVID-19 Antibodies and Outcomes among Outpatient Maintenance Hemodialysis Patients.

Background: Patients on maintenance hemodialysis are particularly vulnerable to infection and hospitalization from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Due to immunocompromised patients and the clustering that occurs in outpatient dialysis units, the seroprevalence of COVID-19 antibodies in this population is unknown and has significant implications for public health. Also, little is known about their risk factors for hospitalization.

Evolution and evolving resolution of controversy over existence and prevalence of cerebral/renal salt wasting.

Purpose Of Review: The topic of hyponatremia is in a state of flux. We review a new approach to diagnosis that is superior to previous methods. It simplifies identifying the causes of hyponatremia, the most important issue being the differentiation of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) from cerebral/renal salt wasting (RSW).

Determining Fractional Urate Excretion Rates in Hyponatremic Conditions and Improved Methods to Distinguish Cerebral/Renal Salt Wasting From the Syndrome of Inappropriate Secretion of Antidiuretic Hormone.

Our evaluation of hyponatremic patients is in a state of confusion because the assessment of the volume status of the patient and determinations of urine sodium concentrations (UNa) >30-40 mEq/L have dominated our approach despite documented evidence of many shortcomings. Central to this confusion is our inability to differentiate cerebral/renal salt wasting (C/RSW) from the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), syndromes with diametrically opposing therapeutic goals. The recent proposal to treat most or all hyponatremic patients makes differentiation even more important and reports of C/RSW occurring without cerebral disease leads to a clinically important proposal to change cerebral to renal salt wasting (RSW).

High Prevalence of Renal Salt Wasting Without Cerebral Disease as Cause of Hyponatremia in General Medical Wards.

Background: The approach to hyponatremia is in a state of flux, especially in differentiating syndrome of inappropriate antidiuretic hormone secretion (SIADH) from cerebral-renal salt wasting (RSW) because of diametrically opposite therapeutic goals. Considering RSW can occur without cerebral disease, we determined the prevalence of RSW in the general hospital wards.

Methods: To differentiate SIADH from RSW, we used an algorithm based on fractional excretion (FE) of urate and nonresponse to saline infusions in SIADH as compared to excretion of dilute urines and prompt increase in serum sodium in RSW.

Application of established pathophysiologic processes brings greater clarity to diagnosis and treatment of hyponatremia.

Hyponatremia, serum sodium < 135 mEq/L, is the most common electrolyte abnormality and is in a state of flux. Hyponatremic patients are symptomatic and should be treated but our inability to consistently determine the causes of hyponatremia has hampered the delivery of appropriate therapy. This is especially applicable to differentiating syndrome of inappropriate antidiuresis (SIAD) from cerebral salt wasting (CSW) or more appropriately, renal salt wasting (RSW), because of divergent therapeutic goals, to water-restrict in SIAD and administer salt and water in RSW.

Identifying Different Causes of Hyponatremia With Fractional Excretion of Uric Acid.

Background: There is controversy over the prevalence of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) and cerebral or renal salt wasting (RSW), 2 syndromes with identical common clinical and laboratory parameters but different therapies. The traditional approach to the hyponatremic patient relies on volume assessment, but there are limitations to this method.

Methods: We used an algorithm that relies on fractional excretion of urate (FEurate) to evaluate patients with hyponatremia and present 4 illustrative cases.

Differentiating SIADH from Cerebral/Renal Salt Wasting: Failure of the Volume Approach and Need for a New Approach to Hyponatremia.

Hyponatremia is the most common electrolyte abnormality. Its diagnostic and therapeutic approaches are in a state of flux. It is evident that hyponatremic patients are symptomatic with a potential for serious consequences at sodium levels that were once considered trivial.

Reversible anuric acute kidney injury secondary to acute renal autoregulatory dysfunction.

Autoregulation of glomerular capillary pressure via regulation of the resistances at the afferent and efferent arterioles plays a critical role in maintaining the glomerular filtration rate over a wide range of mean arterial pressure. Angiotensin II and prostaglandins are among the agents which contribute to autoregulation and drugs which interfere with these agents may have a substantial impact on afferent and efferent arteriolar resistance. We describe a patient who suffered an episode of anuric acute kidney injury following exposure to a nonsteroidal anti-inflammatory agent while on two diuretics, an angiotensin-converting enzyme inhibitor, and an angiotensin receptor blocker.

Is it cerebral or renal salt wasting?

Cerebral salt-wasting (CSW), or renal salt-wasting (RSW), has evolved from a misrepresentation of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) to acceptance as a distinct entity. Challenges still confront us as we attempt to differentiate RSW from SIADH, ascertain the prevalence of RSW, and address reports of RSW occurring without cerebral disease. RSW is redefined as 'extracellular volume depletion due to a renal sodium transport abnormality with or without high urinary sodium concentration, presence of hyponatremia or cerebral disease with normal adrenal and thyroid function.

More on renal salt wasting without cerebral disease: response to saline infusion.

Background And Objectives: The existence and prevalence of cerebral salt wasting (CSW) or the preferred term, renal salt wasting (RSW), and its differentiation from syndrome of inappropriate antidiuretic hormone (SIADH) have been controversial. This controversy stems from overlapping clinical and laboratory findings and an inability to assess the volume status of these patients. The authors report another case of RSW without clinical cerebral disease and contrast it to SIADH.

Treating interdialytic hyperkalemia with fludrocortisone.

Hyperkalemia is a frequent and dangerous problem in dialysis patients. Many factors contribute to potentially life-threatening potassium elevation and most remedies used to treat hyperkalemia are handicapped by the consequences of the separate pools of intra- and extracellular potassium. Besides the kidney, the colon has the ability to excrete potassium, which can help lower total body potassium.