Prognostic Impact of Dysnatremia in COVID-19 Pneumonia: Risk Stratification of Hospitalized Patients (preprint)

Background Severe dysnatremia is associated with poor prognosis and worse outcome and therefore needs more attention to unravel its relation with poor prognosis in patients admitted with coronavirus disease 2019 (COVID-19). Aim of our study was to determine varying degree of dysnatremia among hospitalized COVID-19 patients and identify the clinical outcome associated with it.Method This is a retrospective record analysis study done on the hospitalized COVID-19 patients in Guwahati Neurological Research Centre Medical, North Guwahati. For every included patient, his or her medical records were extracted from a standardized electronic medical record collection system and scrutinised anonymously.Results COVID-19 positive participants were divided into four categories like, dysnatremic (serum sodium > 146 or < 134 mmol/L), hypernatremic (> 146 mmol/L), hyponatremic (< 134 mmol/L) and eunatremic (134 ‒ 146 mmol/L). Total 37.9% of the included COVID-19 participants exhibited dysnatremia compared to only 20% of the patients from the control group demonstrating a significant difference (p = 0.02). Hypernatremia was significantly high (p = 0.01) compared to hyponatremia among COVID-19 positive participants (27.7% vs 12.3%) and also turned out to be relatively severe with significantly high ICU admittance (p < 0.0001) and mortality rate (p = 0.01). Magnitude of dysnatremic patients showing aberration in the circulatory level of the other laboratory parameters was significantly high to that of eunatremic group with high fatality rate among hypernatremic. Both hyper and hyponatremic group demonstrated significantly high SOFA score but increased mortality risk, based on CURB 65 score and 2.35 fold increased probability of death was observed in hypernatremic group.Conclusion Dysnatremia, with special mention to hypernatremia, is associated with increased casualty rate, aberrant laboratory parameters and ICU admittance. This highlights the significance of considering dysnatremia as a predictive outcome marker and thus directs a correct path for appropriate management of COVID-19 patients.

Baseline electrolyte disorders predict disease severity and mortality in patients with COVID-19.

Distinguishing critical laboratory biomarkers for disease severity at the time of hospital presentation is important for early identification of patients who are most likely to have poor outcomes and effective use of health resources. This study aimed to evaluate whether electrolyte imbalances on hospital admission predict severe disease and mortality in patients with coronavirus disease 2019 (COVID-19). We retrospectively collected data on the blood electrolyte concentrations of 286 COVID-19 patients at admission. The correlations between electrolyte imbalances, inflammation, and thrombosis markers in COVID-19 patients were also evaluated. We assessed the predictive performance of baseline blood electrolyte concentrations for severe disease and death using receiver operating characteristic curve analysis and multivariate logistic regression methods. Abnormalities in serum sodium, calcium, and potassium levels at admission were found at 20.6%, 14%, and 4.2%, respectively in this study. In the receiver operating characteristic curve analyses, hypocalcemia and hyponatremia effectively predicted disease progression to hospitalization (area under the curve 0.82, P < .001 and 0.81, P < .001, respectively) and 30-day mortality (area under the curve 0.85, P < .001 and 0.91, P < .001, respectively). In the multivariate logistic regression analysis, baseline hypocalcemia was identified as an independent risk factor associated with the risk of hospitalization (ß = 2.019, P = .01; odds ratio: 7.53). Baseline hypocalcemia and hyponatremia effectively predicted disease progression toward hospitalization and 30-day mortality in patients with COVID-19. Clinicians should closely follow up or reevaluate COVID-19 patients with baseline electrolyte disorders.

Low-solute hyponatremia in a kidney transplant recipient.

BACKGROUND AND AIMS: Electrolyte and acid-base disturbances are common in kidney transplant recipients, but there are few reports of low-solute hyponatremia or beer potomania in this population. We report herein a case of low-solute hyponatremia in a kidney transplant recipient with impaired graft function, highlighting key issues in diagnosis and management of low-solute hyponatremia, as well as exploring the pathophysiology of hyponatremia after kidney transplantation. CASE PRESENTATION: A 51-year-old man who had received a cadaveric renal transplant 18 years before presented with symptomatic hyponatremia and seizure. Workup for an underlying intracranial pathology was negative, and subsequent biochemical workup suggested low-solute hyponatremia with potomania, arising from dietary modifications taken by the patient while self-isolating during the COVID-19 pandemic. Correction of hyponatremia was successful with conservative management with close monitoring. CONCLUSION: This case illustrates key points in the diagnosis and management of low-solute hyponatremia and highlights the pathophysiology of hyponatremia after kidney transplantation.

A Case Series of Acute Symptomatic Hyponatremia due to SIADH in mild COVID-19 Infection (preprint)

Syndrome of Inappropriate anti diuretic hormone (SIADH) is one of the commonest cause of hyponatremia among  medical inpatients. Over recent years, the evolution of SARS-COV-2 infection has led to atypical presentations of  acute symptomatic hyponatremia secondary to isolated SIADH exclusive of pneumonia. We report an unusual case  series of acute symptomatic hyponatremia secondary to SIADH in Category 2 COVID-19 infection. In our case series, all the patients presented with symptoms of acute severe hyponatremia and were incidentally  screened positive for the SARS-COV-2 virus without respiratory tract symptoms and normal chest imaging. They were fully vaccinated and boosted at least three months before the presentation. Clinical and biochemical workups confirmed SIADH in all three patients. They were treated with hypertonic saline initially, followed by fluid restriction  as per recommendations. It was postulated that the most likely mechanism responsible for the inappropriate ADH  secretion is mediated by the increased inflammatory cytokines, especially interleukin-6 and the direct effect of the  SARS-COV2 infection. In the context of the COVID-19 pandemic, atypical presentations of acute symptomatic hyponatremia without an  apparent cause could be an isolated manifestation of SARS-COV-2 infection. Awareness of this condition is essential  for the early institution of the treatment protocol for this reversible and life-threatening disorder

An Unsuspected Case of Rocky Mountain Spotted Fever: A Lesson to Keep a Broad Differential.

Rocky Mountain spotted fever (RMSF), a tick-borne illness, can cause serious illness or death even in a healthy individual. Unfortunately, this illness can be difficult to diagnose as symptoms are nonspecific and oftentimes mimic benign viral illnesses. Delayed diagnosis can be detrimental as the timing of antibiotic administration is critical to prevent associated morbidity and mortality. A careful travel and social history can sometimes provide clues to make the diagnosis. Being aware of lesser-known objective findings such as hyponatremia, neurologic derangements, transaminitis, and thrombocytopenia may help raise suspicion for the disease. This is a case of a 72-year-old woman who presented with nonspecific symptoms and hyponatremia without known tick exposure. She was eventually diagnosed with RMSF. The timing of her presentation corresponded with a surge in COVID-19 infections throughout her area of residence, which further complicated her presentation and contributed to a delayed diagnosis.

Serum soluble Fas ligand is a severity and mortality prognostic marker for COVID-19 patients.

Finding cytokine storm initiator factors associated with uncontrolled inflammatory immune response is necessary in COVID-19 patients. The aim was the identification of Fas/Fas Ligand (FasL) role in lung involvement and mortality of COVID-19 patients. In this case-control study, mild (outpatient), moderate (hospitalized), and severe (ICU) COVID-19 patients and healthy subjects were investigated. RNA isolated from PBMCs for cDNA synthesis and expression of mFas/mFasL mRNA was evaluated by RT-PCR. Serum sFas/sFasL protein by ELISA and severity of lung involvement by CT-scan were evaluated. Also, we docked Fas and FasL via Bioinformatics software (in silico) to predict the best-fit Fas/FasL complex and performed molecular dynamics simulation (MDS) in hyponatremia and fever (COVID-19 patients), and healthy conditions. mFasL expression was increased in moderate and severe COVID-19 patients compared to the control group. Moreover, mFas expression showed an inverse correlation with myalgia symptom in COVID-19 patients. Elevation of sFasL protein in serum was associated with reduced lung injury and mortality. Bioinformatics analysis confirmed that blood profile alterations of COVID-19 patients, such as fever and hyponatremia could affect Fas/FasL complex interactions. Our translational findings showed that decreased sFasL is associated with lung involvement; severity and mortality in COVID-19 patients. We think that sFasL is a mediator of neutrophilia and lymphopenia in COVID-19. However, additional investigation is suggested. This is the first report describing that the serum sFasL protein is a severity and mortality prognostic marker for the clinical management of COVID-19 patients.

Associations of Dysnatremia with COVID-19 Status and Mortality.

Background: In patients without COVID-19, dysnatremia is associated with mortality. These relationships are not well established in patients with COVID-19. We tested the hypotheses that patients with COVID-19 were more likely to have dysnatremia than those without COVID-19 and that, among those with COVID-19, dysnatremia is associated with mortality. Methods: We conducted a retrospective observational study of patients admitted to a tertiary care center in the Bronx, New York, during the COVID-19 surge from March 11 to April 26, 2020. Using multinomial logistic regression models, we compared the prevalence of hypernatremia (serum sodium ≥150 mEq/L) and hyponatremia (serum sodium <130 mEq/L) on admission between patients with and without COVID-19. Among patients with COVID-19, we used Cox proportional hazards models to examine the association of dysnatremia with mortality. Results: Compared with those without COVID-19 (n=1265), patients with COVID-19 (n=3345) had a higher prevalence of hypernatremia (7% versus 4%, P<0.001) and hyponatremia (7% versus 6%, P=0.04). In adjusted models, COVID-19-positive patients had a higher likelihood of having hypernatremia (adjusted odds ratio=1.87, 95% CI, 1.3 to 2.57, P=0.001) compared with COVID-19-negative patients, whereas the association between hyponatremia and COVID-19 status was no longer significant (P=0.06). Among patients with COVID-19, 775 (23%) died after a median follow-up of 17 days (IQR 7-27 days). Among nonsurvivors, 15% had hypernatremia and 8% had hyponatremia on admission. Hypernatremia was associated with a higher risk of mortality (adjusted hazard ratio=1.28, 95% CI, 1.01 to 1.63, P=0.04) compared with patients with eunatremia. Conclusions: In patients hospitalized during the spring 2020 COVID-19 surge, COVID-19 status was associated with hypernatremia on admission. Among patients with COVID-19, hypernatremia was associated with higher mortality. Hypernatremia may be a potential prognostic marker for mortality in COVID-19 patients.

A Variant Mutation in the gene encoding Mitochondrial Seryl-tRNA Synthetase Cause HUPRA Syndrome with Atypical Presentation-A Case Report (preprint)

Background Hyperuricemia, pulmonary hypertension, renal failure, and alkaline intoxication syndrome (HUPRA syndrome) is a rare autosomal recessive mitochondrial disease with prevalence of less than one in a million. Due to mutations in the mitochondrial SARS enzyme encoding seryl-tRNA synthetase on chromosome 19 (19q13.2). Case–Diagnosis/Treatment We investigated two Palestinian girls from the same village presented with progressive renal failure in infancy were diagnosed with this multisystemic disease. presented with atypical clinical manifestations of HUPRA syndrome include leukopenia, anemia, salt wasting resulting in hyponatremia and hypochloremia, renal failure with elevated blood lactate, marked hyperuricemia, hypercholesterolemia and hypertriglyceridemia but  without  pulmonary hypertension or alkaline intoxication that distinguish them from the rest of the usual cases, instead they showed acidosis in routine follow up. By using single exome sequencing analysis, we identified a two homozygous pathogenic mutation c.1175A>G (p.D392G), c.1169A>G (D390G) in SARS2 gene. This sequence identified a new variant mutation of HUPRA syndrome c.1175A>G (p.D392G) with atypical presentation, that will be added to the literature. Conclusion SARS2 gene with pathogenic homozygous mutation variants were detected in our two patients c.1175A>G (p.D392G), c.1169A>G (D390G) in exon 13, with atypical clinical manifestations of HUPRA syndrome, expanding the spectrum of SARS2 pathogenic variants with its characteristic findings, describing the differences in clinical manifestations between homozygous and compound heterozygous mutations.

Effect of Electrolyte Imbalance on Mortality and Late Acute Kidney Injury in Hospitalized COVID-19 Patients.

INTRODUCTION: As a multisystem illness, Coronavirus disease 2019 (COVID-19) can damage different organs. This study investigated the effect of electrolyte imbalance (EI), with or without concomitant renal dysfunction, on the prognosis of COVID-19 in hospitalized patients. METHODS: We evaluated 499 hospitalized patients with confirmed COVID-19, without a history of chronic kidney disease. The patients' demographic data, laboratory values, and outcomes were retrospectively collected from the hospital information system. Serumelectrolytes including sodium, potassium, magnesium, calcium, and phosphorus abnormalities were analyzed on admission and during the hospitalization period. The outcomes of this study were the occurrence of acute kidney injury (AKI) after the first week of hospitalization and in-hospital mortality rate. Multivariate analyses were carried out to obtain the independent risk of each EI on mortality, by adjusting for age, gender, and AKI occurrence. RESULTS: Among the 499 COVID-19 patients (60.9% male), AKI occurred in 168 (33.7%) and mortality in 92 (18.4%) cases. Hypocalcemia (38%) and hyponatremia (22.6%) were the most prevalent EIs, and all EIs were more common in the AKI group than in the non-AKI group. Hyponatremia (Adjusted Odds ratio [AOR] = 2.34, 95% CI: 1.30 to 4.18), hypernatremia (AOR = 8.52, 95% CI: 1.95 to 37.32), and hyperkalemia (AOR = 4.63, 95% CI: 1.65 to 13) on admission were associated with poor prognosis. Moreover, hyponatremia (AOR = 3.02, 95% CI: 1.28 to 7.15) and hyperphosphatemia (AOR = 5.12, 95% CI: 1.24 to 21.09) on admission were associated with late AKI occurrence. CONCLUSION: This study highlights the role of hyponatremia, hypernatremia, hyperkalemia, and hyperphosphatemia in poor prognosis of COVID-19. According to the independent effect of EI on late AKI and mortality, we recommend physicians to raise awareness to closely monitor and correct EI during hospitalization.  DOI: 10.52547/ijkd.6904.

[Update on the diagnosis and management of SIADH and Diabetes insipidus]. / SIADH & Diabetes insipidus: Neues zu Diagnosestellung und Therapie.

Dysnatremia is a common occurrence in patients with COVID-19 and is associated with higher mortality and risk for septic conditions. The pathomechanisms are probably multifaceted, but severe hyponatremia may also occur as a result of underlying SIADH or hypocortisolism. Patients with preexisting AVP dysfunction, like SIADH or diabetes insipidus, are at high risk for severe electrolyte imbalances in the event of a COVID-19 infection.The recently growing use of immune checkpoint inhibitors in oncology is associated with a spectrum of endocrine immune-related adverse events (endocrine irAEs). These AEs usually occur unpredictably and may even manifest after discontinuation of the anticancer therapy. Hyponatremia is a common factor of several endocrine irAEs and may serve as a red flag biomarker for possibly underlying endocrine irAEs such as hypophysitis or adrenalitis. New-onset hyponatremia should always prompt a comprehensive diagnostic workup and exclusion of endocrine irAEs before the diagnosis of SIADH is made.Hyponatremia with severe symptoms should be treated with hypertonic (3 %) saline solution to resolve the cerebral edema and prevent from detrimental neurological sequelae. Both rapid intermittent bolus (RIB) therapy and continuous infusion therapy have now been reported to be safe and equally effective. The RIB therapy limits the risk of overcorrection and requires less often re-lowering treatment than continuous infusion therapy.Fluid restriction has long been considered as first-line treatment of chronic hyponatremia due to SIADH. Additional treatment with Furosemid and/or oral NaCl tablets does not improve efficacy but reduces tolerance to therapy.Copeptin-based dynamic tests show higher diagnostic accuracy in the differential diagnosis of patients with hypotonic polyuria polydipsia syndrome than the indirect water deprivation test.

Approach to the Patient: Hyponatremia and the Syndrome of Inappropriate Antidiuresis (SIAD).

Hyponatremia is the most common electrolyte disturbance seen in clinical practice, affecting up to 30% of acute hospital admissions, and is associated with significant adverse clinical outcomes. Acute or severe symptomatic hyponatremia carries a high risk of neurological morbidity and mortality. In contrast, chronic hyponatremia is associated with significant morbidity including increased risk of falls, osteoporosis, fractures, gait instability, and cognitive decline; prolonged hospital admissions; and etiology-specific increase in mortality. In this Approach to the Patient, we review and compare the current recommendations, guidelines, and literature for diagnosis and treatment options for both acute and chronic hyponatremia, illustrated by 2 case studies. Particular focus is concentrated on the diagnosis and management of the syndrome of inappropriate antidiuresis. An understanding of the pathophysiology of hyponatremia, along with a synthesis of the duration of hyponatremia, biochemical severity, symptomatology, and blood volume status, forms the structure to guide the appropriate and timely management of hyponatremia. We present 2 illustrative cases that represent common presentations with hyponatremia and discuss the approach to management of these and other causes of hyponatremia.

Baseline laboratory parameters for preliminary diagnosis of COVID-19 among children: a cross-sectional study.

BACKGROUND: Clinical judgment of initial baseline laboratory tests plays an important role in triage and preliminary diagnosis among coronavirus disease 2019 (COVID-19) patients. OBJECTIVES: To determine the differences in laboratory parameters between COVID-19 and COVID-like patients, and between COVID-19 and healthy children. Additionally, to ascertain whether healthy children or patients with COVID-like symptoms would form a better control group. DESIGN AND SETTING: Cross-sectional study at the Institute for Child and Youth Health Care of Vojvodina, Novi Sad, Serbia. METHODS: A retrospective study was conducted on 42 pediatric patients of both sexes with COVID-19. Hematological parameters (white blood cell count, absolute lymphocyte count and platelet count) and biochemical parameters (natremia, kalemia, chloremia, aspartate aminotransferase [AST], alanine aminotransferase [ALT], lactate dehydrogenase [LDH] and C-reactive protein [CRP]) were collected. The first control group was formed by 80 healthy children and the second control group was formed by 55 pediatric patients with COVID-like symptoms. RESULTS: Leukocytosis, lymphopenia, thrombocytosis, elevated systemic inflammatory index and neutrophil-lymphocyte ratio, hyponatremia, hypochloremia and elevated levels of AST, ALT, LDH and CRP were present in COVID patients, in comparison with healthy controls, while in comparison with COVID-like controls only lymphopenia was determined. CONCLUSIONS: The presence of leukocytosis, lymphopenia, thrombocytosis, elevated systemic inflammatory index and neutrophil-lymphocyte ratio, hyponatremia, hypochloremia and elevated levels of AST, ALT, LDH and CRP may help healthcare providers in early identification of COVID-19 patients. Healthy controls were superior to COVID-like controls since they provided better insight into the laboratory characteristics of children with novel betacoronavirus (SARS-CoV-2) infection.

Serum Glucose and Electrolyte Levels in Children with and without Febrile Seizures: A case-control study (preprint)

Background: Febrile seizures (FS) occur in children aged six to sixty months with a febrile illness not associated with a central nervous system infection or metabolic disorder. Risk factors include; age, history of the disease, certain vaccinations, or iron and zinc deficiencies. Studies show significant hyponatremia, hypocalcemia, and hyperkalemia in children with febrile seizures. Similarly, cerebrospinal fluid hyperglycemia is common in febrile convulsions. This study aimed to retrospectively assess the relationship between febrile seizures, and electrolyte & glucose imbalance among children with fever, and also compare the annual trends of febrile seizure-related admissions pre- and post-Covid 19 pandemics. Methods:  A case-control study was conducted from January 2018 to January 2022 at Zhongnan Hospital of Wuhan University, Hubei, China. 876 children aged 6 to 60 months were divided into 438 cases with febrile seizures (cases) and 438 with fever but without seizures (controls). Serum glucose and electrolyte levels at the time of hospitalization as well as age, gender, birth weight, gestational age, temperature, and causes of fever, in both groups were retrieved, analyzed, and compared. Results: Febrile seizure admissions among children aged 6-60 months were significantly reduced to less than 23.4% during the Covid-19 pandemic. Children with febrile seizures had significantly higher serum glucose levels than those with fever but without seizures (p < 0.05). The serum sodium levels of children with seizures were significantly lower than those without seizures (p < 0.05). Sodium levels were significantly lower among children with complex seizures (p < 0.05). There was no significant difference in the serum electrolyte levels of potassium and calcium between the cases and controls (p > 0.05). A significant positive correlation was found between serum sodium levels and the occurrence of febrile seizures (r = [0.156]; p < 0.05). Conclusion: The study found that admission rates for febrile seizures decreased during Covid-19 and lower sodium levels could be a risk factor for the occurrence of febrile seizures.

Hyponatremia and SARS-CoV-2 infection: A narrative review.

A novel rapid spreading and changing virus called SARS-CoV-2 appeared in Wuhan city in December 2019. It was announced by the World Health Organization (WHO) as a pandemic disease in March 2020. It commonly presents with respiratory symptoms; however, it may be asymptomatic. Electrolyte abnormalities are not uncommon features of SARS-CoV-2 infection. Hyponatremia is one of these electrolyte disturbances among SARS-CoV-2 patients, and it may produce symptoms such as weakness and seizure as the initial presenting symptoms. The underlying mechanism(s) of hyponatremia due to SARS-CoV-2 infection is (are) not established. The aim of this review is to evaluate the possible mechanism of hyponatremia in patients with COVID-19. Understanding and categorizing the hyponatremia in these patients will lead to better treatment and correction of the hyponatremia. A review of the literature between December 2019 and March 2022 was conducted searching for the possible reported mechanism(s) of hyponatremia in SARS-CoV-2. Although SIADH is the commonly reported cause of hyponatremia in SARS-CoV-2 infection, other causes such as diarrhea, vomiting, and kidney salt loss must be considered before SIADH.

Symptomatic hyponatremia after ChAdOx1 nCoV-19 coronavirus disease-19 vaccination.

Adverse events, particularly severe adverse events, after coronavirus disease vaccination are the primary concern for many patients. We present the first report of symptomatic hyponatremia, a potentially life-threatening condition, after administration of the ChAdOx1 nCoV-19 coronavirus disease-19 vaccine. A 24-year-old man developed altered consciousness and high-grade fever a day after receiving this vaccine. Computed tomography of the brain showed diffuse brain swelling with bilateral descending transtentorial brain herniation. His serum sodium level, urine sodium level, and urine osmolarity were 114 mEq/L, 77 mEq/L, and 230 mOsm/kg, respectively. He was diagnosed with symptomatic hyponatremia due to syndrome of inappropriate antidiuretic hormone. His symptoms rapidly improved after treatment with 3% NaCl. Seven days after admission, his serum sodium level was normal, and no further intervention was required. We believe that the vaccine was the trigger for hyponatremia in this case based on temporal relationship of vaccination and hyponatremia, the rapid improvement of the patient, and the transient nature of the hyponatremia. We postulate that cytokine underlies the pathophysiology of hyponatremia in this case. Recognition of adverse events after coronavirus disease-19 vaccination is essential. Symptomatic hyponatremia should be included in the differential diagnosis in altered-consciousness patients after administration of ChAdOx1 nCoV-19 coronavirus disease-19 vaccine.

Kidney Transplant Recipient with Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH) Secondary to COVID-19 Pneumonia: A Case Report.

BACKGROUND: Currently, COVID-19 is becoming one of the most common causes of viral pneumonia worldwide. In the medical literature, very few case reports describe the association between COVID-19 and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) in kidney transplant patients. METHODS: A 74-year-old immunocompromised man post-kidney transplant presented with nonspecific symptoms consisting of fatigue, malaise, and anorexia. He was also found to have hyponatremia in the context of pulmonary insults. SIADH in the setting of COVID-19 pneumonia was diagnosed after exclusion of other causes of hyponatremia. He was treated for COVID-19 pneumonia with antiviral therapy, secondary bacterial infection prophylaxis, dexamethasone and ventilatory support in addition to modification of antirejection medications. RESULTS: The patient has improved and his serum sodium normalized with management of primary insult. CONCLUSIONS: SIADH should be suspected in transplant patients with COVID-19 pneumonia once they develops hyponatremia. The decision of intravenous fluid administration should be taken carefully in these settings.

The Role of Na+/K+-ATPase in the Development of Hyponatrenemia under Conditions of Hypoxic Stress in Patients with SARS-CoV-2 Infection.

We studied laboratory parameters of patients with COVID-19 against the background of chronic pathologies (cardiovascular pathologies, obesity, type 2 diabetes melitus, and cardiovascular pathologies with allergy to statins). A decrease in pH and a shift in the electrolyte balance of blood plasma were revealed in all studied groups and were most pronounced in patients with cardiovascular pathologies with allergy to statin. It was found that low pH promotes destruction of lipid components of the erythrocyte membranes in patients with chronic pathologies, which was seen from a decrease in Na+/K+-ATPase activity and significant hyponatrenemia. In patients with cardiovascular pathologies and allergy to statins, erythrocyte membranes were most sensitive to a decrease in pH, while erythrocyte membranes of obese patients showed the greatest resistance to low pH and oxidative stress.

Sodium and water perturbations in patients who had an acute stroke: clinical relevance and management strategies for the neurologist.

Sodium and water perturbations, manifesting as hyponatraemia and hypernatraemia, are common in patients who had an acute stroke, and are associated with worse outcomes and increased mortality. Other non-stroke-related causes of sodium and water perturbations in these patients include underlying comorbidities and concomitant medications. Additionally, hospitalised patients who had an acute stroke may receive excessive intravenous hypotonic solutions, have poor fluid intake due to impaired neurocognition and consciousness, may develop sepsis or are administered drugs (eg, mannitol); factors that can further alter serum sodium levels. Sodium and water perturbations can also be exacerbated by the development of endocrine consequences after an acute stroke, including secondary adrenal insufficiency, syndrome of inappropriate antidiuretic hormone secretion and diabetes insipidus. Recently, COVID-19 infection has been reported to increase the risk of development of sodium and water perturbations that may further worsen the outcomes of patients who had an acute stroke. Because there are currently no accepted consensus guidelines on the management of sodium and water perturbations in patients who had an acute stroke, we conducted a systematic review of the literature published in English and in peer-reviewed journals between January 2000 and December 2020, according to PRISMA guidelines, to assess on the current knowledge and clinical practices of this condition. In this review, we discuss the signs and symptoms of hyponatraemia and hypernatraemia, the pathogenesis of hyponatraemia and hypernatraemia, their clinical relevance, and we provide our recommendations for effective treatment strategies for the neurologist in the management of sodium and water perturbations in commonly encountered aetiologies of patients who had an acute stroke.