Extracellular sodium regulates fibroblast growth factor 23 (FGF23) formation.

The bone-derived hormone fibroblast growth factor-23 (FGF23) has recently received much attention due to its association with chronic kidney disease and cardiovascular disease progression. Extracellular sodium concentration ([Na+]) plays a significant role in bone metabolism. Hyponatremia (lower serum [Na+]) has recently been shown to be independently associated with FGF23 levels in patients with chronic systolic heart failure. However, nothing is known about the direct impact of [Na+] on FGF23 production. Here, we show that an elevated [Na+] (+20 mM) suppressed FGF23 formation, whereas low [Na+] (-20 mM) increased FGF23 synthesis in the osteoblast-like cell lines UMR-106 and MC3T3-E1. Similar bidirectional changes in FGF23 abundance were observed when osmolality was altered by mannitol but not by urea, suggesting a role of tonicity in FGF23 formation. Moreover, these changes in FGF23 were inversely proportional to the expression of NFAT5 (nuclear factor of activated T cells-5), a transcription factor responsible for tonicity-mediated cellular adaptations. Furthermore, arginine vasopressin, which is often responsible for hyponatremia, did not affect FGF23 production. Next, we performed a comprehensive and unbiased RNA-seq analysis of UMR-106 cells exposed to low versus high [Na+], which revealed several novel genes involved in cellular adaptation to altered tonicity. Additional analysis of cells with Crisp-Cas9-mediated NFAT5 deletion indicated that NFAT5 controls numerous genes associated with FGF23 synthesis, thereby confirming its role in [Na+]-mediated FGF23 regulation. In line with these in vitro observations, we found that hyponatremia patients have higher FGF23 levels. Our results suggest that [Na+] is a critical regulator of FGF23 synthesis.

Systems Biology of the Vasopressin V2 Receptor: New Tools for Discovery of Molecular Actions of a GPCR.

Systems biology can be defined as the study of a biological process in which all of the relevant components are investigated together in parallel to discover the mechanism. Although the approach is not new, it has come to the forefront as a result of genome sequencing projects completed in the first few years of the current century. It has elements of large-scale data acquisition (chiefly next-generation sequencing-based methods and protein mass spectrometry) and large-scale data analysis (big data integration and Bayesian modeling). Here we discuss these methodologies and show how they can be applied to understand the downstream effects of GPCR signaling, specifically looking at how the neurohypophyseal peptide hormone vasopressin, working through the V2 receptor and PKA activation, regulates the water channel aquaporin-2. The emerging picture provides a detailedframework for understanding the molecular mechanisms involved in water balance disorders, pointing the way to improved treatment of both polyuric disorders and water-retention disorders causing dilutional hyponatremia.

Urea transporter UT-A1 as a novel drug target for hyponatremia.

Hyponatremia is the most common disorder of electrolyte imbalances. It is necessary to develop new type of diuretics to treat hyponatremia without losing electrolytes. Urea transporters (UT) play an important role in the urine concentrating process and have been proved as a novel diuretic target. In this study, rat and mouse syndromes of inappropriate antidiuretic hormone secretion (SIADH) models were constructed and analyzed to determine if UTs are a promising drug target for treating hyponatremia. Experimental results showed that 100 mg/kg UT inhibitor 25a significantly increased serum osmolality (from 249.83 ± 5.95 to 294.33 ± 3.90 mOsm/kg) and serum sodium (from 114 ± 2.07 to 136.67 ± 3.82 mmol/L) respectively in hyponatremia rats by diuresis. Serum chemical examination showed that 25a neither caused another electrolyte imbalance nor influenced the lipid metabolism. Using UT-A1 and UT-B knockout mouse SIADH model, it was found that serum osmolality and serum sodium were lowered much less in UT-A1 knockout mice than in UT-B knockout mice, which suggest UT-A1 is a better therapeutic target than UT-B to treat hyponatremia. This study provides a proof of concept that UT-A1 is a diuretic target for SIADH-induced hyponatremia and UT-A1 inhibitors might be developed into new diuretics to treat hyponatremia.

Vascular Calcification Is Accelerated by Hyponatremia and Low Osmolality.

BACKGROUND: Hyponatremia, frequently observed in patients with chronic kidney disease, is associated with increased cardiovascular morbidity and mortality. Hyponatremia or low osmolality induces oxidative stress and cell death, both of which accelerate vascular calcification (VC), a critical phenotype in patients with chronic kidney disease. Whether hyponatremia or low osmolality plays a role in the pathogenesis of VC is unknown. METHODS: Human vascular smooth muscle cells (VSMCs) and mouse aortic rings were cultured in various osmotic conditions and calcifying medium supplemented with high calcium and phosphate. The effects of low osmolality on phenotypic change and oxidative stress in the cultured VSMCs were examined. Microarray analysis was conducted to determine the main signaling pathway of osmolality-related VC. The transcellular sodium and calcium ions flux across the VSMCs were visualized by live imaging. Furthermore, the effect of osmolality on calciprotein particles (CPPs) was investigated. Associations between arterial intimal calcification and hyponatremia or low osmolality were examined by a cross-sectional study using human autopsy specimens obtained in the Hisayama Study. RESULTS: Low osmolality exacerbated calcification of the ECM (extracellular matrix) of cultured VSMCs and mouse aortic rings. Oxidative stress and osteogenic differentiation of VSMCs were identified as the underlying mechanisms responsible for low osmolality-induced VC. Microarray analysis showed that low osmolality activated the Rac1 (Ras-related C3 botulinum toxin substrate 1)-Akt pathway and reduced NCX1 (Na-Ca exchanger 1) expression. Live imaging showed synchronic calcium ion efflux and sodium ion influx via NCX1 when extracellular sodium ion concentrations were increased. An NCX1 inhibitor promoted calcifying media-induced VC by reducing calcium ion efflux. Furthermore, low osmolality accelerated the generation and maturation steps of CPPs. The cross-sectional study of human autopsy specimens showed that hyponatremia and low osmolality were associated with a greater area of arterial intimal calcification. CONCLUSIONS: Hyponatremia and low osmolality promote VC through multiple cellular processes, including the Rac1-Akt pathway activation.

A pragmatic, open-label, randomized controlled trial of Plasma-Lyte-148 versus standard intravenous fluids in children receiving kidney transplants (PLUTO).

Acute electrolyte and acid-base imbalance is experienced by many children following kidney transplant. This is partly because doctors give very large volumes of artificial fluids to keep the new kidney working. When severe, fluid imbalance can lead to seizures, cerebral edema and death. In this pragmatic, open-label, randomized controlled trial, we randomly assigned (1:1) pediatric kidney transplant recipients to Plasma-Lyte-148 or standard of care perioperative intravenous fluids (predominantly 0.45% sodium chloride and 0.9% sodium chloride solutions). We then compared clinically significant electrolyte and acid-base abnormalities in the first 72 hours post-transplant. The primary outcome, acute hyponatremia, was experienced by 53% of 68 participants in the Plasma-Lyte-148 group and 58% of 69 participants in the standard fluids group (odds ratio 0·77 (0·34 - 1·75)). Five of 16 secondary outcomes differed with Plasma-Lyte-148: hypernatremia was significantly more frequent (odds ratio 3·5 (1·1 - 10·8)), significantly fewer changes to fluid prescriptions were made (rate ratio 0·52 (0·40-0·67)), and significantly fewer participants experienced hyperchloremia (odds ratio 0·17 (0·07 - 0·40)), acidosis (odds ratio 0·09 (0·04 - 0·22)) and hypomagnesemia (odds ratio 0·21 (0·08 - 0·50)). No other secondary outcomes differed between groups. Serious adverse events were reported in 9% of participants randomized to Plasma-Lyte-148 and 7% of participants randomized to standard fluids. Thus, perioperative Plasma-Lyte-148 did not change the proportion of children who experienced acute hyponatremia compared to standard fluids. However fewer fluid prescription changes were made with Plasma-Lyte-148, while hyperchloremia and acidosis were less common.

Chronic Hyponatremia and Brain Structure and Function Before and After Treatment.

RATIONALE & OBJECTIVE: Hyponatremia is the most common electrolyte disorder and is associated with significant morbidity and mortality. This study investigated neurocognitive impairment, brain volume, and alterations in magnetic resonance imaging (MRI)-based measures of cerebral function in patients before and after treatment for hyponatremia. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: Patients with presumed chronic hyponatremia without signs of hypo- or hypervolemia treated in the emergency department of a German tertiary-care hospital. EXPOSURE: Hyponatremia (ie, plasma sodium concentration [Na+]<125mmol/L) before and after treatment leading to [Na+]>130mmol/L. OUTCOMES: Standardized neuropsychological testing (Mini-Mental State Examination, DemTect, Trail Making Test A/B, Beck Depression Inventory, Timed Up and Go) and resting-state MRI were performed before and after treatment of hyponatremia to assess total brain and white and gray matter volumes as well as neuronal activity and its synchronization. ANALYTICAL APPROACH: Changes in outcomes after treatment for hyponatremia assessed using bootstrapped confidence intervals and Cohen d statistic. Associations between parameters were assessed using correlation analyses. RESULTS: During a 3.7-year period, 26 patients were enrolled. Complete data were available for 21 patients. Mean [Na+]s were 118.4mmol/L before treatment and 135.5mmol/L after treatment. Most measures of cognition improved significantly. Comparison of MRI studies showed a decrease in brain tissue volumes, neuronal activity, and synchronization across all gray matter after normalization of [Na+]. Volume effects were particularly prominent in the hippocampus. During hyponatremia, synchronization of neuronal activity was negatively correlated with [Na+] (r=-0.836; 95% CI, -0.979 to-0.446) and cognitive function (Mini-Mental State Examination, r=-0.523; 95% CI, -0.805 to-0.069; DemTect, r=-0.744; 95% CI, -0.951 to-0.385; and Trail Making Test A, r=0.692; 95% CI, 0.255-0.922). LIMITATIONS: Small sample size, insufficient quality of several MRI scans as a result of motion artifact. CONCLUSIONS: Resolution of hyponatremia was associated with improved cognition and reductions in brain volumes and neuronal activity. Impaired cognition during hyponatremia is closely linked to increased neuronal activity rather than to tissue volumes. Furthermore, the hippocampus appears to be particularly susceptible to hyponatremia, exhibiting pronounced changes in tissue volume. PLAIN-LANGUAGE SUMMARY: Hyponatremia is a common clinical problem, and patients often present with neurologic symptoms that are at least partially reversible. This study used neuropsychological testing and magnetic resonance imaging to examine patients during and after correction of hyponatremia. Treatment led to an improvement in patients' cognition as well as a decrease in their brain volumes, spontaneous neuronal activity, and synchronized neuronal activity between remote brain regions. Volume effects were particularly prominent in the hippocampus, an area of the brain that is important for the modulation of memory. During hyponatremia, patients with the lowest sodium concentrations had the highest levels of synchronized neuronal activity and the poorest cognitive test results.

Hyponatremia and takotsubo syndrome: a review of pathogenetic and clinical implications.

Hyponatremia is a common electrolyte abnormality with important prognostic and therapeutic implications. It might exert detrimental effects on various organ systems including the central nervous system (CNS), bone, and heart along with its potential association with poor quality of life. These adverse effects might be largely mediated through a variety of mechanisms including osmotic stress, dysfunctional transmembrane exchangers, and enhanced oxidative stress.Interestingly, hyponatremia might also have an important association with takotsubo syndrome (TTS) that has been universally considered as a reversible form of cardiomyopathy usually emerging in response to various stressors. In this context, severe hyponatremia was previously reported to serve as a direct trigger of TTS evolution largely through its potential impact on CNS and heart. However, pathogenetic and clinical implications of hyponatremia still need to be thoroughly evaluated in patients with TTS. This paper aims to analyze the clinical features of published cases with TTS primarily triggered by hyponatremia and also aims to discuss the association between hyponatremia and TTS from a broader perspective.

Dysnatremia in a changing climate: A global systematic review of the association between serum sodium and ambient temperature.

OBJECTIVE: Both hyponatremia and hypernatremia have been reported to occur more frequently with higher ambient temperatures, although the underlying mechanisms are not well understood. Global temperatures are rising due to climate change, which may impact the incidence of dysnatremia worldwide. We aimed to identify, collate and critically appraise studies analyzing the relationship between climate measures (outdoor temperature, humidity) and serum sodium concentrations. DESIGN: Systematic review, reported in accordance with PRISMA guidelines. METHODS: MEDLINE and Embase were searched with relevant key terms. Studies assessing the effect on serum sodium measurement of elevated temperature or humidity versus a comparator were included. RESULTS: Of 1466 potentially relevant studies, 34 met inclusion criteria, originating from 23 countries spanning all inhabited continents. The majority (30 of 34, 88%) reported a significant association between outdoor temperature and dysnatremia, predominantly lower serum sodium with increased ambient temperature. Humidity had a less consistent effect. Individuals aged above 65 years, children, those taking diuretics and antidepressants, those with chronic renal impairment or those undertaking physical exertion had increased vulnerability to heat-associated dysnatremia. The risk of bias was assessed to be high in all but four studies. CONCLUSIONS: Higher ambient temperature is consistently associated with an increased incidence of hyponatremia. We infer that hyponatremia presentations are likely to rise with increasing global temperatures and the frequency of extreme heat events secondary to climate change. Evidence-based public health messages, clinician education and reduction in fossil fuel consumption are necessary to reduce the expected burden on healthcare services worldwide.

High Osmol Gap Hyponatremia Caused by Icodextrin: A Case Series Report.

Recently, hyperosmolar hyponatremia following excessive off-label use of two exchanges of 2 L icodextrin daily during peritoneal dialysis (PD) was reported. We encountered a cluster of 3 cases of PD patients who developed hyperosmolar hyponatremia during on-label use of icodextrin. This appeared to be due to absorption of icodextrin since after stopping icodextrin, the serum sodium level and osmol gap returned to normal, while a rechallenge again resulted in hyperosmolar hyponatremia. We excluded higher than usual concentrations of specific fractions of dextrins in fresh icodextrin dialysis fluid (lot numbers of used batches were checked by manufacturer). We speculate that in our patients, either an exaggerated degradation of polysaccharide chains by α-amylase activity in dialysate, lymph, and interstitium and/or rapid hydrolysis of the absorbed larger degradation products in the circulation may have contributed to the hyperosmolality observed, with the concentration of oligosaccharides exceeding the capacity of intracellular enzymes (in particular maltase) to metabolize these products to glucose. Both hyponatremia and hyperosmolality are risk factors for poor outcomes in PD patients. Less conventional PD prescriptions such as off-label use of two exchanges of 2 L icodextrin might raise the risk of this threatening side effect. This brief report is intended to create awareness of a rare complication of on-label icodextrin use in a subset of PD patients and/or PD prescriptions.

Myelinolysis cases presenting with manic attack after rapid correction of hyponatremia: Two cases.

OBJECTIVE: Myelinolysis is a neurological condition that can display diverse psychiatric symptoms, with electrolyte imbalance, alcoholism and malnutrition being the frequent causes. Rapid correction of hyponatremia may trigger pontine and extra-pontine myelinolysis. CASES: This paper examines two cases: one of hyponatremia after antihypertensive use and the other of myelinolysis due to rapid correction of hyponatremia. Since myelinolysis appeared as a manic episode, the patients sought treatment at the psychiatry outpatient clinic. Further tests were conducted to rule out organic causes and the diagnosis was confirmed prior to referring the patients to the neurology clinic. CONCLUSION: Psychiatrists should be meticulous in excluding organic causes in first-episode mania and consider these possibilities in the differential diagnosis for the pertinent patient group.

Effect of midodrine on HVPG in advanced chronic liver disease and acute-on-chronic liver failure-A pilot study.

BACKGROUND AND AIMS: Nonselective beta-blockers (NSBB) are the mainstay for treatment of portal hypertension (PH), but require caution in decompensated cirrhosis (DC) or acute-on-chronic liver failure (ACLF) with hypotension, hyponatremia, acute kidney injury (AKI) or type 2 hepatorenal syndrome (HRS). Midodrine is oral, rapidly acting, α1-adrenergic agonist. We evaluated acute effects of midodrine on hepatic venous pressure gradient (HVPG) in DC and ACLF with contraindications to NSBB. METHODS: Patients of DC (n = 30) with grade III ascites and serum sodium (Na) <130/systolic blood pressure (SBP) <90/type II HRS (group I) and ACLF patients (n = 30) with Na <130/SBP <90/AKI (group II) were included. HVPG was done at baseline and repeated 3 h after 10 mg midodrine. Primary outcome was HVPG response (reduction by >20% or to <12 mmHg). RESULTS: In group I, midodrine significantly reduced HVPG (19.2 ± 4.6 to 17.8 ± 4.2, p = .02) and heart rate (HR) (86.3 ± 11.6 to 77.9 ± 13.1, p < .01) and increased mean arterial pressure (MAP) (74.1 ± 6.9 to 81.9 ± 6.6 mmHg, p < .01). In group II also, midodrine reduced HVPG (19.1 ± 4.1 to 17.0 ± 4.2) and HR (92.4 ± 13.7 to 84.6 ± 14.1) and increased MAP (85.4 ± 7.3 to 91.2 ± 7.6 mmHg), p < .01 for all. HVPG response was achieved in 3/30 (10%) in group I and 8/30 (26.7%) in group II. On logistic regression analysis, prerenal AKI (OR 11.04, 95% CI 1.83-66.18, p < .01) and increase in MAP (OR 1.22, 95% CI 1.03-1.43, p = .02) were independent predictors of response. Increase in MAP by 8.5 mmHg with midodrine had best cut-off with AUROC of .76 for response. CONCLUSION: In decompensated cirrhosis and ACLF patients with contraindications to NSBB, midodrine is useful in decreasing HVPG. Dose of midodrine should be titrated to increase MAP atleast by 8.5 mmHg.

Hyponatremia - Treatment standard 2024.

Hyponatremia is the most common electrolyte disorder in hospital patients associated with increased morbidity, mortality, hospital stay and financial burden. The speed of a correction with 3% sodium chloride as 100 mL IV bolus or continuous infusion depends on the severity and persistence of the symptoms, and needs frequent biochemical monitoring. The rapid intermittent administration of hypertonic saline is preferred for treatment of symptomatic hyponatremia. In asymptomatic mild hyponatremia, an adequate solute intake with an initial fluid restriction (FR) of 500 mL/d adjusted according to the serum sodium levels is preferred. Almost half of the syndrome of inappropriate diuresis hormone (SIADH) patients do not respond to FR as first-line therapy. At present, urea and tolvaptan are considered as most effective second-line therapies in SIADH. However, the evidence for guidance on the choice of second-line therapy of hypotonic hyponatremia is lacking. Oral urea is considered as very effective and safe treatment. Mild and asymptomatic hyponatremia is treated with adequate solute intake (salt and protein) and an initial FR with adjustments based on serum sodium levels. Specific treatment with vaptans may be considered in either euvolemic or hypervolemic patients with high ADH activity. In order to ensure optimal patient outcome, a close monitoring and readiness for administration of either hypotonic fluids or desmopressin may be crucial in decision making process for specific treatment and eventual overcorrection consequences. According to the guidelines, a gradual correction and clinical evaluation is preferable over the rapid normalization of serum sodium towards the laboratory reference ranges.

Clinical factors associated with hyponatremia correction during treatment with oral Urea.

BACKGROUND AND HYPOTHESIS: Oral urea is being used more commonly to treat hyponatremia, but factors contributing to the correction rate are unknown. We hypothesized that clinically relevant factors can be identified to help guide hyponatremia correction with oral urea. METHODS: Retrospective study in two university hospitals including hospitalized patients with hyponatremia (plasma sodium < 135 mmol/L) treated with oral urea. Linear mixed-effects models were used to identify factors associated with hyponatremia correction. Rates of overcorrection, osmotic demyelination and treatment discontinuation were also assessed. RESULTS: We included 161 urea treatment episodes in 140 patients (median age 69 years, 46% females, 93% syndrome of inappropriate antidiuresis). Oral urea succeeded fluid restriction in 117 treatment episodes (73%), was combined with fluid restriction in 104 treatment episodes (65%) and was given as only treatment in 27 treatment episodes (17%). A median dose of 30 grams/day of urea for 4 days (interquartile range 2-7 days) increased plasma sodium from 127 to 134 mmol/L and normalized hyponatremia in 47% of treatment episodes. Older age (ß 0.09, 95%CI 0.02 to 0.16), lower baseline plasma sodium (ß -0.65, 95%CI -0.78 to -0.62), and higher cumulative urea dose (ß 0.03, 95%CI -0.02 to -0.03) were independently associated with a greater rise in plasma sodium. Concurrent fluid restriction was associated with a greater rise in plasma sodium only during the first 48 h of treatment (ß 1.81, 95%CI 0.40 to 3.08). Overcorrection occurred in 5 cases (3%), no cases of osmotic demyelination were identified, and oral urea was discontinued in 11 cases (11%) due to side-effects. CONCLUSION: During treatment with oral urea, older age, higher cumulative dose, lower baseline plasma sodium and initial fluid restriction are associated with a greater correction rate of hyponatremia. These factors may guide clinicians to achieve a gradual correction of hyponatremia with oral urea.

Hyponatremia is associated with unfavorable outcomes after reperfusion treatment in acute ischemic stroke.

BACKGROUND AND PURPOSE: In patients with acute ischemic stroke, hyponatremia (plasma sodium < 136 mmol/L) is common and associated with unfavorable outcomes. However, data are limited for patients who underwent intravenous thrombolysis (IVT) and/or endovascular thrombectomy (EVT). Therefore, our aim was to assess the impact of hyponatremia on postreperfusion outcomes. METHODS: We analyzed data of consecutive patients who presented with acute ischemic stroke and were treated with IVT and/or EVT at Isala Hospital, the Netherlands, in 2019 and 2020. The primary outcome measure was the adjusted common odds ratio (acOR) for a worse modified Rankin Scale (mRS) score at 3-month follow-up. Secondary outcomes included symptomatic intracranial hemorrhage, in-hospital mortality, infarct core, and penumbra volumes. RESULTS: Of the 680 patients (median age = 73 years, 49% female, median National Institutes of Health Stroke Scale = 5), 430 patients (63%) were treated with IVT, 120 patients (18%) with EVT, and 130 patients (19%) with both. Ninety-two patients (14%) were hyponatremic on admission. Hyponatremia was associated with a worse mRS score at 3 months (acOR = 1.76, 95% confidence interval [CI] = 1.12-2.76) and in-hospital mortality (aOR = 2.39, 95% CI = 1.23-4.67), but not with symptomatic intracranial hemorrhage (OR = 1.17, 95% CI = 0.39-3.47). Hyponatremia was also associated with a larger core (17.2 mL, 95% CI = 2.9-31.5) and core to penumbra ratio (55.0%, 95% CI = 7.1-102.9). CONCLUSIONS: Admission hyponatremia in patients with acute ischemic stroke treated with IVT and/or EVT was independently associated with unfavorable postreperfusion outcomes, a larger infarct core, and a larger core to penumbra ratio. Future studies should address whether correction of hyponatremia improves the prognosis.

Hyponatremia as a Marker for Predicting Surgical Intervention in Necrotizing Enterocolitis: A Retrospective Cohort Study.

INTRODUCTION: To investigate the predictive value of plasma sodium at the onset of necrotizing enterocolitis (NEC) diagnosis in distinguishing surgical NEC from medical NEC. METHODS: A retrospective review of all NEC neonates treated at our hospital between 2008 and 2022. Patients were divided into two groups based on treatment methods: surgical intervention and medical treatment. Patient demographics, laboratory parameters, and outcomes were all documented. The values of laboratory parameters were collected at the onset of NEC and after treatment. To identify potential predictors of surgical NEC, multivariate logistic regression analyses were used. The receiver operating characteristic curve was applied to determine predictive factors. RESULTS: Surgical treatment was performed in 111 infants (44.6%), and medical treatment in 138 cases (55.4%). Of 249 infants with NEC, 22 patients exhibited Bell stage I, 91 infants had Bell stage II, and 136 patients displayed Bell stage III. We discovered that white blood cell (WBC), C-reactive protein (CRP), fibrinogen, and sodium were independent predictors of NEC receiving surgery based on the results of the multivariate logistic regression analysis. Hyponatremia was found in 122 of the 249 patients (49%). At the onset of NEC diagnosis, hyponatremia was found in 83.8% of surgical intervention group and in 21.0% of medical treatment group (P < 0.001). Sensitivity, specificity, positive predictive value, and negative predictive value for WBC, CRP, fibrinogen, and sodium were calculated. The cutoff values were determined using receiver operating characteristic analysis. The area under the curve of hyponatremia for surgical intervention was 0.875, with 84% sensitivity, 80% specificity, 77% positive predictive value, and 86% negative predictive value, which had a greater specificity (0.80) for predicting surgical intervention than WBC (0.67), CRP (0.50), and fibrinogen (0.70). CONCLUSIONS: When a surgical evaluation is necessary, hyponatremia can effectively distinguish surgical NEC from medical NEC. It could be used as a predictive marker to guide parental counseling for surgical intervention and rapid transfer of patients to tertiary centers when they have a surgical condition.

Utilization of aquapheresis among hospitalized patients with end-stage liver disease: A case series and literature review.

Third-spacing of fluid is a common complication in hospitalized patients with decompensated cirrhosis. In addition to ascites, patients with advanced cirrhosis may develop significant peripheral edema, which may limit mobility and exacerbate debility and muscle wasting. Concomitant kidney failure and cardiac dysfunction may lead to worsening hypervolemia, which may ultimately result in pulmonary edema and respiratory compromise. Diuretic use in such patients may be limited by kidney dysfunction and electrolyte abnormalities, including hyponatremia and hypokalemia. A slow, continuous form of ultrafiltration known as aquapheresis is a method of extracorporeal fluid removal whereby a pump generates a transmembrane pressure that forces an isotonic ultrafiltrate across a semipermeable membrane. This leads to removal of an ultrafiltrate that is isotonic to blood without the need for dialysate or replacement fluid as is necessary in other forms of continuous kidney replacement therapy. This technique has been utilized in other conditions including acute decompensated heart failure, with trials showing mixed, but generally favorable results. Herein, we present a series of our own experience using aquapheresis among patients with cirrhosis, review the literature regarding its use in other hypervolemic states, and discuss how we may apply lessons learned from use of aquapheresis in heart failure to patients with end-stage liver disease.

Hyponatremia in the emergency department: an overview of diagnostic and therapeutic approach.

INTRODUCTION: Hyponatremia, defined as a serum sodium concentration <135 mmol/l, is a frequent electrolyte disorder in patients presenting to an emergency department (ED). In this context, appropriate diagnostic and therapeutic management is rarely performed and challenging due to complex pathophysiologic mechanisms and a variety of underlying diseases. OBJECTIVE: To implement a feasible pathway of central diagnostic and therapeutic steps in the setting of an ED. METHODS: We conducted a narrative review of the literature, considering current practice guidelines on diagnosis and treatment of hyponatremia. Underlying pathophysiologic mechanisms and management of adverse treatment effects are outlined. We also report four cases observed in our ED. RESULTS: Symptoms associated with hyponatremia may appear unspecific and range from mild cognitive deficits to seizures and coma. The severity of hyponatremia-induced neurological manifestation and the risk of poor outcome is mainly driven by the rapidity of serum sodium decrease. Therefore, emergency treatment of hyponatremia should be guided by symptom severity and the assumed onset of hyponatremia development, distinguishing acute (<48 hours) versus chronic hyponatremia (>48 hours). CONCLUSIONS: Especially in moderately or severely symptomatic patients presenting to an ED, the application of a standard management approach appears to be critical to improve overall outcome. Furthermore, an adequate work-up in the ED enables further diagnostic and therapeutic evaluation during hospitalization.

Clinical Impact and Risk Factors of Seizure After Liver Transplantation: A Nested Case-Control Study.

Seizures are a frequent neurological consequence following liver transplantation (LT), however, research on their clinical impact and risk factors is lacking. Using a nested case-control design, patients diagnosed with seizures (seizure group) within 1-year post-transplantation were matched to controls who had not experienced seizures until the corresponding time points at a 1:5 ratio to perform survival and risk factor analyses. Seizures developed in 61 of 1,243 patients (4.9%) at median of 11 days after LT. Five-year graft survival was significantly lower in the seizure group than in the controls (50.6% vs. 78.2%, respectively, p < 0.001) and seizure was a significant risk factor for graft loss after adjusting for variables (HR 2.04, 95% CI 1.24-3.33). In multivariable logistic regression, body mass index <23 kg/m2, donor age ≥45 years, intraoperative continuous renal replacement therapy and delta sodium level ≥4 mmol/L emerged as independent risk factors for post-LT seizure. Delta sodium level ≥4 mmol/L was associated with seizures, regardless of the severity of preoperative hyponatremia. Identifying and controlling those risk factors are required to prevent post-LT seizures which could result in worse graft outcome.

Efficacy of oral sodium chloride in reducing the incidence of hyponatremia in children with epilepsy receiving oxcarbazepine monotherapy: A randomized controlled trial (SCHO Trial).

INTRODUCTION: Hyponatremia is a well-documented adverse effect of oxcarbazepine treatment, but no clinical trial has yet been conducted to explore any intervention for reducing the incidence of hyponatremia. MATERIALS AND METHODS: This open-label trial evaluated the efficacy of add-on daily oral sodium chloride supplementation of 1-2 g/day for 12 weeks in reducing the incidence of hyponatremia in children receiving oxcarbazepine monotherapy aged 1-18 years. Apart from comparing the incidence of symptomatic and severe hyponatremia, serum and urine sodium levels, serum and urine osmolality, changes in behavior and cognition, and the number of participants with recurrence of seizures and requiring additional antiseizure medication (ASM) were also compared. RESULTS: A total of 120 children (60 in each group) were enrolled. The serum sodium level at 12 weeks in the intervention group was higher than that of the control group (136.5 ± 2.6 vs 135.4 ± 2.5 mEq/L, p = 0.01). The number of patients with hyponatremia was significantly lower in the intervention group (4/60vs14/60, p = 0.01). However, the incidence of symptomatic and severe hyponatremia (0/60vs1/60, p = 0.67 for both), changes in social quotient and child behavior checklist total score (0.6 ± 0.8 vs 0.7 ± 0.5, p = 0.41 and 0.9 ± 1.2 vs 1.1 ± 0.9, p = 0.30 respectively), the number of patients with breakthrough seizures (9/60vs10/60, p = 0.89), and the number of patients requiring additional ASMs (8/60vs10/60, p = 0.79) were comparable in both groups. CONCLUSIONS: Daily oral sodium chloride supplementation is safe and efficacious in reducing the incidence of hyponatremia in children with epilepsy receiving oxcarbazepine monotherapy. However, sodium chloride supplementation does not significantly reduce more clinically meaningful outcome measures like symptomatic and severe hyponatremia. Trial registry No. CTRI/2021/12/038388.

Midodrine reduces new-onset acute kidney injury and hyponatremia in children with cirrhosis and ascites awaiting liver transplantation: Results from an open-label RCT.

OBJECTIVES: Midodrine, an oral α-1-adrenergic receptor agonist, counters arterial hypovolemia and reduces complications in adult patients with cirrhosis. This randomized controlled trial (RCT) aimed to assess the efficacy and safety of midodrine in preventing complications and improving survival in children with cirrhosis and ascites who are awaiting liver transplantation (LT). METHODS: This open-label RCT conducted from January 2022 to May 2023 included children under 18 years with cirrhosis and ascites. Patients were randomized to receive either midodrine plus standard medical therapies (SMTs) or SMT alone. The primary outcome measure was the incidence of cirrhosis-related complications within 6 months. RESULTS: Thirty-five subjects were enrolled and randomized. Patients in the midodrine arm had a lower incidence of new-onset acute kidney injury (AKI) compared with the SMT arm (11.1% vs. 41.2%). Patients in the midodrine arm showed a decline in serum creatinine and improvement in glomerular filtration rate, whereas no changes were observed in the SMT arm. There was a lower incidence of new-onset hyponatremia in the midodrine arm (20% vs. 56%). Midodrine led to reduction in plasma rennin activity (PRA) and improvement in systemic hemodynamics. There was no difference in the rate of resolution of ascites, recurrence of ascites, requirement of therapeutic paracentesis, cumulative albumin infusion requirement, episodes of spontaneous bacterial peritonitis, and hepatic encephalopathy between the two arms. CONCLUSION: Midodrine, when added to SMT, was effective in reducing the incidence of new-onset AKI and hyponatremia in pediatric cirrhotics awaiting LT. It also improved systemic hemodynamics and showed a trend towards reducing PRA.