Serum sodium alterations in SARS CoV-2 (COVID-19) infection: impact on patient outcome

Syndrome of inappropriate antidiuresis/hyponatremia in COVID-19

Hyponatremia is the most frequent electrolyte alteration among hospitalized patients and it has been reported in 20-40% of patients with SARS-CoV-2 (COVID-19) infection. Multiple causes of hyponatremia have been hypothesized in these patients. The syndrome of inappropriate antidiuresis (SIAD) has been considered one of the main reasons leading to hyponatremia in this condition. SIAD can be secondary to cytokines release, in particular IL-6. Positive pressure ventilation can be another cause of hyponatremia due to SIAD. Other possible etiologies of hyponatremia in COVID-19 patients can be related to secondary hypocortisolism, nausea, vomiting, heart and kidney damage. Similar to many other clinical conditions, there is strong evidence that hyponatremia is associated with a worse prognosis also in patients with COVID-19 infection. In particular, hyponatremia has been identified as an independent risk of ICU transfer, need of non-invasive ventilation and death. Hyponatremia in COVID-19 patients is in principle acute and symptomatic and should be treated as such, according to the published guidelines. Therefore, patients should be initially treated with i.v. hypertonic saline (3% NaCl) infusion and serum [Na+] should be frequently monitored, in order to remain within a safe rate of correction. There is evidence showing that serum [Na+] correction is associated with a better outcome in different pathologies, including COVID-19 infection.

Implications of Dysnatremia and Endocrine Disturbances in COVID-19 Patients

Sodium imbalance is a common electrolyte disturbance in COVID-19, often linked to disruptions in hormonal regulation. This review explores the relationship between sodium dysregulation and endocrine disturbances, particularly focusing on primary and secondary hypothyroidism, hypocortisolism, and the renin-angiotensin-aldosterone system (RAAS). Hypocortisolism in COVID-19, due to adrenal insufficiency or secondary to pituitary dysfunction, can lead to hyponatremia through inadequate cortisol levels, which impair renal free water excretion and enhance antidiuretic hormone (ADH) secretion. Similarly, hypothyroidism is associated with decreased renal blood flow and the glomerular filtration rate (GFR), which also increases ADH activity, leading to water retention and dilutional hyponatremia. Furthermore, COVID-19 can disrupt RAAS (primarily through its interaction with the angiotensin-converting enzyme 2 (ACE2) receptor), diminishing aldosterone secretion and further contributing to sodium loss and hyponatremia. These hormonal disruptions suggest that sodium imbalance in COVID-19 is multifactorial and warrants further investigation into the complex interplay between COVID-19, endocrine function, and sodium homeostasis. Future research should focus on understanding these mechanisms to develop management algorithms that address both sodium imbalance and underlying hormonal disturbances in order to improve prognosis and outcomes in COVID-19 patients.

The Relationship between the Laboratory Biomarkers of SARS-CoV-2 Patients with Type 2 Diabetes at Discharge and the Severity of the Viral Pathology

In this study, we evaluated the discharge status of patients with type 2 diabetes mellitus and SARS-CoV-2 infection, focusing on the inflammatory profile through biomarkers such as procalcitonin, CRP, LDH, fibrinogen, ESR, and ferritin, as well as electrolyte levels and the prior diagnosis of diabetes or its identification at the time of hospitalization. We assessed parameters at discharge for 45 patients admitted to the Clinical Hospital "Gavril Curteanu" Oradea between 21 October 2021, and 31 December 2021, randomly selected, having as the main inclusion criteria the positive RT-PCR rapid antigen test for viral infection and the diagnosis of type 2 diabetes. At discharge, patients with type 2 diabetes registered significantly lower mean procalcitonin levels among those who survived compared to those who died from COVID-19. In our study, ferritin and hemoglobin values in individuals with type 2 diabetes were outside the reference range at discharge and correlated with severe or moderate forms of COVID-19 infection. Additionally, elevated ferritin levels at discharge were statistically associated with hypokalemia and elevated levels of ESR at discharge. Another strong statistically significant correlation was identified between high CRP levels at discharge, strongly associated (p < 0.001) with elevated LDH and fibrinogen levels in patients with type 2 diabetes and SARS-CoV-2 viral infection. The increase in CRP was inversely statistically associated with the tendency of serum potassium to decrease at discharge in patients with type 2 diabetes and COVID-19. Identifying type 2 diabetes metabolic pathology at the time of hospitalization for SARS-CoV-2 infection, compared to pre-infection diabetes diagnosis, did not significantly influence the laboratory parameter status at the time of discharge. At the discharge of patients with type 2 diabetes and viral infection with the novel coronavirus, procalcitonin was significantly reduced in those who survived COVID-19 infection, and disease severity was significantly correlated with hyperferritinemia and decreased hemoglobin at discharge. Hyperferritinemia in patients with type 2 diabetes and COVID-19 at discharge was associated with hypokalemia and persistent inflammation (quantified by ESR at discharge). The low number of erythrocytes at discharge is associated with maintaining inflammation at discharge (quantified by the ESR value).

Impact of hyponatremia in patients hospitalized in Internal Medicine units: Hyponatremia in Internal Medicine units

The aim of this study was to analyze the impact and the clinical and evolutionary characteristics of hypotonic hyponatremia in patients hospitalized in Internal Medicine units. Prospective multicenter observational study of patients with hypotonic hyponatremia (<135 mmol/L) in 5 hospitals in southern Spain. Patients were included according to point prevalence studies carried out every 2 weeks between March 2015 and October 2017, by assessing demographic, clinical, analytical, and management data; each patient was subsequently followed up for 12 months, during which time mortality and readmissions were assessed. A total of 501 patients were included (51.9% women, mean age = 71.3 ± 14.24 years), resulting in an overall prevalence of hyponatremia of 8.3%. The mean comorbidities rate was 4.50 ± 2.41, the most frequent diagnoses being heart failure (115) (23%), respiratory infections (65) (13%), and oncological pathologies (42) (6.4%). Of the total number of hyponatremia cases, 180 (35.9%) were hypervolemic, 164 (32.7%) hypovolemic, and 157 (31.3%) were euvolemic. A total of 87.4% did not receive additional diagnostic tests to establish the origin of the condition and 30% did not receive any treatment. Hospital mortality was 15.6% and the mean length of stay was 14.7 days. Euvolemic and admission hyponatremia versus hyponatremia developed during admission were significantly associated with lower mortality rates (P = .037). Mortality at 1 year and readmissions were high (31% and 53% of patients, respectively). Hyponatremia was common in Internal Medicine areas, with hypervolemic hyponatremia being the most frequent type. The mortality rate was high during admission and at follow-up; yet there is a margin for improvement in the clinical management of this condition.

Hyponatremia after COVID-19 is frequent in the first year and increases re-admissions

Hyponatremia on admission has been related to worse outcomes in patients with COVID-19 infection. However, little is known about the frequency and the associated risk factors of hyponatremia after COVID-19 discharge. We performed an observational 24-month follow-up study of patients admitted during the first COVID-19 wave. Kaplan-Meier curves and Cox proportional hazard models were used to assess the main variables in predicting hyponatremia on follow-up (HYPO-FU). A total of 161 out of 683 (24.4%) developed HYPO-FU. The group with HYPO-FU comprised of more men [(62.3%) vs. (49.2%); p < 0.01], older [65.6 ± 18.2 vs. 60.3 ± 17.0; p < 0.01] and more frequently re-admitted [(16.2%) vs. (3.8%); p < 0.01). The rate of HYPO-FU was higher in the first year 23.6 per 100 individuals per year. After Cox regression analysis, the independent risk factors of HYPO-FU were diabetes [OR 2.12, IC 95% (1.48-3.04)], hypertension [OR 2.18, IC 95% (1.53-3.12)], heart failure [OR 3.34, IC 95% (1.72-6.48)] and invasive ventilation support requirement [OR: 2.38, IC 95% (1.63-3.50)]. To conclude, HYPO-FU was frequent in the first year after COVID-19 infection, and the risk was higher in older men with comorbidities, increasing rehospitalisation. Further studies aimed at evaluating the beneficial effects of correcting hyponatremia in these patients are warranted.

Association of hypernatremia with mortality in patients with COVID-19: A systematic review and meta-analysis

BACKGROUND

The COVID-19 pandemic worldwide has caused varying degrees of severity of lung damage in patients, with acute respiratory distress and death in severe cases. However, this is not directly caused by the virus itself, but by the production of inflammasome by monocytes in the body, leading to a systemic inflammatory response, which results in a very poor clinical prognosis for patients with COVID-19.

OBJECTIVE

The purpose of this meta-analysis was to look at the relationship between hypernatremia and mortality in COVID-19 patients.

METHODS

We searched the PubMed, Web of Science, Embase, and Cochrane databases for articles published from the inception of the database until August 27, 2022. Three researchers reviewed the literature, retrieved data, and assessed the quality of the literature, respectively. A meta-analysis was performed using State 17 software to assess the value of the effect of hypernatremia on mortality in patients with new coronavirus pneumonia.

RESULTS

A total of nine publications was finally included in this study, including a total of 11,801 patients with COVID-19, including 1278 in the hypernatremia group and 10,523 in the normonatremia group. Meta-analysis showed that hypernatremia was associated with mortality in patients with COVID-19 [OR = 4.15, 95% CI (2.95-5.84), p = .002, I² = 66.7%] with a sensitivity of 0.36 [0.26, 0.48] and a specificity of 0.88 [0.83, 0.91]. The posterior probability of mortality was 42% in patients with COVID-19 hypernatremia and 15% in patients who did not have COVID-19 hypernatremia.

CONCLUSION

According to available data, hypernatremia is associated with death in patients with COVID-19.

Pituitary and SARS CoV-2: An unremitting conundrum

There is increased interest related to the impact of coronavirus disease 19 (COVID-19) on the endocrine system and in particular on the pituitary gland. Over the course of the severe infection with acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there are both acute and delayed effects on the pituitary, related to infection and/or treatment. Hypopituitarism, pituitary apoplexy and hypophysitis have been all reported, as well as arginine vasopressin deficiency (diabetes insipidus) and syndrome of inappropriate antidiuretic hormone secretion. Furthermore, patients with acromegaly, Cushing's disease and hypopituitarism are theoretically at increased risk of complications with COVID-19 and require close monitoring. Evidence regarding pituitary dysfunction in patients with COVID-19 continues to be gathered, as the breadth and depth of knowledge also continues to rapidly evolve. This review summarizes data analysis to date on the possible effects of COVID-19 and COVID-19 vaccination on patients with normal pituitary function and patients with known pituitary pathology. Though clinical systems were significantly affected, it seems there is no overall loss of biochemical control in patients with certain pituitary pathologies.

Risk Factors Related to the Death of Admitted COVID-19 Patients: A Buffalo Study

Background

Coronavirus disease 2019 (COVID-19) may result in a severe acute respiratory syndrome that leads to a worldwide pandemic. Despite the increasing understanding of COVID-19 disease, the mortality rate of hospitalized COVID-19 patients remains high.

Objective

To investigate the risk factors related to the mortality of admitted COVID-19 patients during the peak of the epidemic from August 2021 to October 2021 in Vietnam.

Methods

This is a prospective cohort study performed at the Hospital for Rehabilitation-Professional diseases. The baseline and demographic data, medical history, clinical examination, the laboratory results were recorded for patients admitted to the hospital with confirmed COVID-19. A radiologist and a pulmonologist will read the chest radiographs on admission and calculate the Brixia scores to classify the severity of lung abnormalities. Patients were followed up until beingrecovered or their death. Comparison of clinical and subclinical characteristics between recovery and death groups to find out risk factors related to the death of COVID-19 patients.

Results

Among 104 admitted COVID-19 patients, men accounted for 42.3%, average age of 61.7 ± 13.7. The most common symptoms were fever 76.9%, breathlessness 74%, and fatigue 53.8%. The majority (84.6%) of the study population had at least one co-morbidity, including hypertension (53.8%), diabetes (25.9%), gastritis (19.2%), ischemic heart disease (15.4) %), stroke (9.6%) and osteoarthritis (9.6%). The rate of mild and moderate COVID-19 is 13.4%, severe 32.7%, and critical 40.4%. There are 88 inpatients (84.6%) who needed respiratory support. The median hospital stay was 13 days (IQR 10-17.75 days). The rate of intubated patients with mechanical ventilation was 31.7%. The overall mortality rate was 29.8%. Risk factors related to death included Brixia scores > 9, Urea > 7 mmol/L, Ferrtin > 578 ng/ml, Failure to get vaccinated, Age > 60 years, and Low Oxygen SpO2 < 87% (BUFFALO).

Conclusion

The main result of the study is the independent risk factors related to the death of admitted COVID-19 patients including Brixia scores > 9, Urea > 7 mmol/L, Ferrtin > 578 ng/ml, Failure to get vaccinated, Age > 60 years, and Low Oxygen SpO2 < 87% ((BUFFALO) which suggests that these COVID-19 patients should be closely followed up.

Relationship between hyponatremia at hospital admission and cardiopulmonary profile at follow-up in patients with SARS-CoV-2 (COVID-19) infection

PURPOSE

Hyponatremia occurs in about 30% of patients with pneumonia, including those with SARS-CoV-2 (COVID-19) infection. Hyponatremia predicts a worse outcome in several pathologic conditions and in COVID-19 has been associated with a higher risk of non-invasive ventilation, ICU transfer and death. The main objective of this study was to determine whether early hyponatremia is also a predictor of long-term sequelae at follow-up.

METHODS

In this observational study, we collected 6-month follow-up data from 189 laboratory-confirmed COVID-19 patients previously admitted to a University Hospital. About 25% of the patients (n = 47) had hyponatremia at the time of hospital admission.

RESULTS

Serum [Na⁺] was significantly increased in the whole group of 189 patients at 6 months, compared to the value at hospital admission (141.4 ± 2.2 vs 137 ± 3.5 mEq/L, p < 0.001). In addition, IL-6 levels decreased and the PaO₂/FiO₂ increased. Accordingly, pulmonary involvement, evaluated at the chest X-ray by the RALE score, decreased. However, in patients with hyponatremia at hospital admission, higher levels of LDH, fibrinogen, troponin T and NT-ProBNP were detected at follow-up, compared to patients with normonatremia at admission. In addition, hyponatremia at admission was associated with worse echocardiography parameters related to right ventricular function, together with a higher RALE score.

CONCLUSION

These results suggest that early hyponatremia in COVID-19 patients is associated with the presence of laboratory and imaging parameters indicating a greater pulmonary and right-sided heart involvement at follow-up.

Hyponatremia and Cancer: From Bedside to Benchside

Hyponatremia is the most common electrolyte disorder encountered in hospitalized patients. This applies also to cancer patients. Multiple causes can lead to hyponatremia, but most frequently this electrolyte disorder is due to the syndrome of inappropriate antidiuresis. In cancer patients, this syndrome is mostly secondary to ectopic secretion of arginine vasopressin by tumoral cells. In addition, several chemotherapeutic drugs induce the release of arginine vasopressin by the hypothalamus. There is evidence that hyponatremia is associated to a more negative outcome in several pathologies, including cancer. Many studies have demonstrated that in different cancer types, both progression-free survival and overall survival are negatively affected by hyponatremia, whereas the correction of serum [Na⁺] has a positive effect on patient outcome. In vitro studies have shown that cells grown in low [Na⁺] have a greater proliferation rate and motility, due to a dysregulation in intracellular signalling pathways. Noteworthy, vasopressin receptors antagonists, which were approved more than a decade ago for the treatment of euvolemic and hypervolemic hyponatremia, have shown unexpected antiproliferative effects. Because of this property, vaptans were also approved for the treatment of polycystic kidney disease. In vitro evidence indicated that this family of drugs effectively counteracts proliferation and invasivity of cancer cells, thus possibly opening a new scenario among the pharmacological strategies to treat cancer.

Electrolyte imbalances as poor prognostic markers in COVID-19: a systemic review and meta-analysis

PURPOSE

Serum electrolyte imbalances are highly prevalent in COVID-19 patients. However, their associations with COVID-19 outcomes are inconsistent, and of unknown prognostic value. We aim to systematically clarify the associations and prognostic accuracy of electrolyte imbalances (sodium, calcium, potassium, magnesium, chloride and phosphate) in predicting poor COVID-19 clinical outcome.

METHODS

PubMed, Embase and Cochrane Library were searched. Odds of poor clinical outcome (a composite of mortality, intensive-care unit (ICU) admission, need for respiratory support and acute respiratory distress syndrome) were pooled using mixed-effects models. The associated prognostic sensitivity, positive and negative likelihood ratios (LR + , LR-) and predictive values (PPV, NPV; assuming 25% pre-test probability), and area under the curve (AUC) were computed.

RESULTS

We included 28 observational studies from 953 records with low to moderate risk-of-bias. Hyponatremia (OR = 2.08, 95% CI = 1.48-2.94, I² = 93%, N = 8), hypernatremia (OR = 4.32, 95% CI = 3.17-5.88, I² = 45%, N = 7) and hypocalcemia (OR = 3.31, 95% CI = 2.24-4.88, I² = 25%, N = 6) were associated with poor COVID-19 outcome. These associations remained significant on adjustment for covariates such as demographics and comorbidities. Hypernatremia was 97% specific in predicting poor outcome (LR + 4.0, PPV = 55%, AUC = 0.80) despite no differences in CRP and IL-6 levels between hypernatremic and normonatremic patients. Hypocalcemia was 76% sensitive in predicting poor outcome (LR- 0.44, NPV = 87%, AUC = 0.71). Overall quality of evidence ranged from very low to moderate.

CONCLUSION

Hyponatremia, hypernatremia and hypocalcemia are associated with poor COVID-19 clinical outcome. Hypernatremia is 97% specific for a poor outcome, and the association is independent of inflammatory marker levels. Further studies should evaluate if correcting these imbalances help improve clinical outcome.

Mechanical ventilation for COVID-19: Outcomes following discharge from inpatient treatment

Though mechanical ventilation (MV) is used to treat patients with severe coronavirus disease 2019 (COVID-19), little is known about the long-term health implications of this treatment. Our objective was to determine the association between MV for treatment of COVID-19 and likelihood of hospital readmission, all-cause mortality, and reason for readmission. This study was a longitudinal observational design with electronic health record (EHR) data collected between 3/1/2020 and 1/31/2021. Participants included 17,652 patients hospitalized for COVID-19 during this period who were followed through 6/30/2021. The primary outcome was readmission to inpatient care following discharge. Secondary outcomes included all-cause mortality and reason for readmission. Rates of readmission and mortality were compared between ventilated and non-ventilated patients using Cox proportional hazards regression models. Differences in reasons for readmission by MV status were compared using multinomial logistic regression. Patient characteristics and measures of illness severity were balanced between those who were mechanically ventilated and those who were not utilizing 1-to-1 propensity score matching. The sample had a median age of 63 and was 47.1% female. There were 1,131 (6.4%) patients who required MV during their initial hospitalization. Rates (32.1% versus 9.9%) and hazard of readmission were greater for patients requiring MV in the propensity score-matched samples [hazard ratio (95% confidence interval) = 3.34 (2.72-4.10)]. Rates (15.3% versus 3.4%) and hazard [hazard ratio (95% confidence interval) = 3.12 (2.32-4.20)] of all-cause mortality were also associated with MV status. Ventilated patients were more likely to be readmitted for reasons which were classified as COVID-19, infectious diseases, and respiratory diagnoses compared to non-ventilated patients. Mechanical ventilation is a necessary treatment for severely ill patients. However, it may be associated with adverse outcomes including hospital readmission and death. More intense post-discharge monitoring may be warranted to decrease this associational finding.

Risk factors for Hyponatremia in COVID-19 hospitalised patients

Objectives

To determine the risk factors for Hyponatremia in Coronavirus disease 2019 (COVID-19) patients.

Methods

Medical records of all patients admitted in COVID-19 Isolation Intensive Care Unit of Farooq Hospital Westwood Branch, Lahore from 1st July to 30th September, 2020 were retrospectively reviewed. Patients with confirmed diagnosis of COVID-19 by Real Time Polymerase Chain Reaction (RT-PCR) and having Hyponatremia (serum Sodium (s/Na+ <135mEq/L) were included, patients with Eunatremia (s/Na+ within 135 - 145mEq/L) were taken as control while subjects with Hypernatremia (s/Na+ >145mEq/L) at admission, incomplete medical records and pregnant females were excluded from the study. Demographic, clinical and laboratory data at time of admission in hospital was extracted.

Results

Of 182 included patients, 79.1% (n=144) were male 40.7% (n=74) had Diabetes Mellitus (DM) and 44.5% (n=81) were hypertensive. Forty seven percent (n=86) patients had Hyponatremia while 52.7% (n=96) were eunatremic. Forty nine percent (n=90) patients had Acute Kidney Injury (AKI) and 4.9% (n=9) patients died. Risk factors for Hyponatremia were age >60 years (OR=2.52, p=0.006); DM (OR=2.79, p=0.001); Hypoxemia (OR=3.74, p<0.001); Lymphopenia (OR=7.62, p<0.009); Hypoalbuminemia (OR=9.15, p<0.001); high serum Ferritin (OR=4.46, p<0.001), high Neutrophil to Lymphocyte Ratio (NLR) (OR=3.58, p<0.001) and AKI (OR=3.40, p<0.001).

Conclusions

Hyponatremia was common in COVID-19 hospitalized patients. Increasing age, DM, Hypoxemia, Hypoalbuminemia, high serum Ferritin and AKI were the most significant risk factors for Hyponatremia. Hyponatremic patients had comparatively higher mortality than Eunatremic patients.

Risk Factors for Longer-Term Mortality in Discharged Patients with Dementia and SARS-CoV-2 Infection: A Matched Case-Control Study

BACKGROUND

Persisting symptoms and increased mortality after SARS-CoV-2 infection has been described in COVID-19 survivors.

OBJECTIVE

We examined longer-term mortality in patients with dementia and SARS-CoV-2 infection.

METHODS

A retrospective matched case-control study of 165 patients with dementia who survived an acute hospital admission with COVID-19 infection, and 1325 patients with dementia who survived a hospital admission but without SARS-CoV-2 infection. Potential risk factors investigated included socio-demographic factors, clinical features, and results of investigations. Data were fitted using a Cox proportional hazard model.

RESULTS

Compared to patients with dementia but without SARS-CoV-2 infection, people with dementia and SARS-CoV-2 infection had a 4.4-fold risk of death (adjusted hazard ratio [aHR] = 4.44, 95% confidence interval [CI] 3.13-6.30) even beyond the acute phase of infection. This excess mortality could be seen up to 125 days after initial recovery but was not elevated beyond this time. Risk factors for COVID-19-associated mortality included prescription of antipsychotics (aHR = 3.06, 95% CI 1.40-6.69) and benzodiazepines (aHR = 3.00, 95% CI 1.28-7.03). Abnormalities on investigation associated with increased mortality included high white cell count (aHR = 1.21, 95% CI 1.04-1.39), higher absolute neutrophil count (aHR = 1.28, 95% CI 1.12-1.46), higher C-reactive protein (aHR = 1.01, 95% CI 1.00-1.02), higher serum sodium (aHR = 1.09, 95% CI 1.01-1.19), and higher ionized calcium (aHR = 1.03, 95% CI 1.00-1.06). The post-acute COVID mortality could be modeled for the first 120 days after recovery with a balanced accuracy of 87.2%.

CONCLUSION

We found an increased mortality in patients with dementia beyond the acute phase of illness. We identified several investigation results associated with increased mortality, and increased mortality in patients prescribed antipsychotics or benzodiazepines.

Association of hypernatremia with outcomes of COVID-19 patients: A protocol for systematic review and meta-analysis

BACKGROUND

This systematic review and meta-analysis aimed to assess the association of hypernatremia with the outcomes of COVID-19 patients.

METHODS

We performed a systematic literature search on PubMed, Google Scholar, and Science Direct until October 2021 and found a total of 131 papers. With meticulous screening finally, 17 papers met the inclusion criteria. COVID-19 patients with sodium levels greater than the reference level were the study population and the outcome of interest was the poor outcome; such as mortality, mechanical ventilation, intensive care unit (ICU) admission, and prolonged hospital stay. The pooled estimate was calculated as the odds ratio (OR).

RESULTS

There were 19,032 patients with hypernatremia in the 17 studies included. An overall random effect meta-analysis showed that hypernatremia was associated with mortality (OR: 3.18 [1.61, 6.28], P < .0001, I2 = 91.99%), prolong hospitalization (OR: 1.97 [1.37, 2.83], P < .001, I2 = 0.00%) and Ventilation (OR: 5.40 [1.89, 15.42], P < .001, I2 = 77.35%), ICU admission (OR: 3.99 [0.89, 17.78], P = .07, I2 = 86.79%). Meta-regression analysis showed the association of age with the ICU outcome of hypernatremia patients. Whereas, other parameters like male, hypertension, chronic kidney disease, and diabetes mellitus did not significantly influence the odds ratio.

CONCLUSION

Hypernatremia was markedly associated with poor outcomes in patients with COVID-19. Hence, a blood ionogram is warranted and special attention must be given to hypernatremia COVID-19 patients.

Inverse relationship between IL-6 and sodium levels in patients with COVID-19 and other respiratory tract infections: data from the COVIVA study

Objective

Hyponatremia in COVID-19 is often due to the syndrome of inadequate antidiuresis (SIAD), possibly mediated by interleukin-6 (IL-6)-induced non-osmotic arginine vasopressin (AVP) secretion. We hypothesized an inverse association between IL-6 and plasma sodium concentration, stronger in COVID-19 compared to other respiratory infections.

Design

Secondary analysis of a prospective cohort study including patients with COVID-19 suspicion admitted to the Emergency Department, University Hospital of Basel, Switzerland, between March and July 2020.

Methods

We included patients with PCR-confirmed COVID-19 and patients with similar symptoms, further subclassified into bacterial and other viral respiratory infections. The primary objective was to investigate the association between plasma sodium and IL-6 levels.

Results

A total of 500 patients were included, 184 (37%) with COVID-19, 92 (18%) with bacterial respiratory infections, and 224 (45%) with other viral respiratory infections. In all groups, median (IQR) IL-6 levels were significantly higher in hyponatremic compared to normonatremic patients (COVID-19: 43.4 (28.4, 59.8) vs 9.2 (2.8, 32.7) pg/mL, P < 0.001; bacterial: 122.1 (63.0, 282.0) vs 67.1 (24.9, 252.0) pg/mL, P < 0.05; viral: 14.1 (6.9, 84.7) vs 4.3 (2.1, 14.4) pg/mL, P < 0.05). IL-6 levels were negatively correlated with plasma sodium levels in COVID-19, whereas the correlation in bacterial and other viral infections was weaker (COVID-19: R = -0.48, P < 0.001; bacterial: R = -0.25, P = 0.05, viral: R = -0.27, P < 0.001).

Conclusions

IL-6 levels were inversely correlated with plasma sodium levels, with a stronger correlation in COVID-19 compared to bacterial and other viral infections. IL-6 might stimulate AVP secretion and lead to higher rates of hyponatremia due to the SIAD in these patients.

Hyponatremia due to excessive water intake in COVID-19 patients: case series study

Background

Literatures revealed syndrome of inappropriate antidiuretic hormone (SIADH) as the most common mechanism of hyponatremia in COVID-19. However, it is important to rule out other etiologies of hyponatremia.

Methods

This is a case series, retrospective study. Four patients were reviewed from the Mesaieed Hospital, Hamad Medical Corporation, Qatar. The patients were admitted during the second wave of pandemic because of mild to moderate COVID pneumonia. The patients received medications according to the protocol; after few days of treatment, their blood laboratory results showed hyponatremia; as compared to the initial readings, hyponatremia workup excluded SIADH. History revealed that the patients were drinking large amounts of water, around 4-5 L/day, due of certain reasons: one patient had dysgeusia, and the other three patients thought that excessive drinking of water is beneficial for COVID-19 infection.

Results

The hyponatremia level was less than 135 mmol/L, other laboratory tests excluded SIADH, and the provisional diagnosis was dilutional hyponatremia. Male/female ratio was 3/1, age from 29- to 45-year-old patients with no associated comorbidities. Fluid restriction up to 1.5 L/day showed dramatic improvement of their sodium blood level. The patients are discharged in a stable condition.

Conclusions

In COVID-19 patients, hyponatremia not only is secondary to SIADH but can also be due to other etiologies. Hyponatremia can be induced by excessive water drinking and considered an extremely rare reported cases.

Real-world effectiveness and protection of SARS-CoV-2 vaccine among patients hospitalized for COVID-19 in Xi'an, China, December 8, 2021, to January 20, 2022: A retrospective study

Introduction

In December 2021, a large-scale epidemic broke out in Xi'an, China, due to SARS-CoV-2 infection. This study reports the effect of vaccination on COVID-19 and evaluates the impact of different vaccine doses on routine laboratory markers.

Methods

The laboratory data upon admission, of 231 cases with COVID-19 hospitalized from December 8, 2021 to January 20, 2022 in Xi'an, including blood routine, lymphocyte subtypes, coagulative function tests, virus specific antibodies and blood biochemical tests were collected and analyzed.

Results

Of the 231 patients, 21 were not vaccinated, 158 were vaccinated with two doses and 52 with three doses. Unvaccinated patients had a higher proportion of moderate and severe symptoms than vaccinated patients, while two-dose vaccinated patients had a higher proportion than three-dose vaccinated patients. SARS-CoV-2 specific IgG levels were significantly elevated in vaccinated patients compared with unvaccinated patients. Particularly, unvaccinated patients had lower counts and percentages of lymphocytes, eosinophils and CD8+ T-lymphocytes, and elevated coagulation-related markers. In addition, vaccination had no effect on liver and kidney function.

Conclusions

Vaccination against SARS-CoV-2, inducing high IgG level and increased CD8+ T cells and eosinophils, and regulating coagulation function, can significantly attenuate symptoms of COVID-19, suggesting that the vaccine remains protective against SARS-CoV-2.

Prevalence and outcomes of hyponatremia among COVID-19 patients: A systematic review and meta-analysis

Objectives

On March 2020, the WHO declared coronavirus disease 2019 (COVID-19) pandemic. COVID-19 is associated with various clinical syndromes, with electrolytes imbalances involved. This review aims to quantify the prevalence and outcomes of hyponatremia among COVID-19 patients, as well as to review the underlying pathophysiological mechanisms of hyponatremia among these patients.

Methods

Using Preferred Reporting Items for Systematic Reviews and Meta Analyses guidelines, we conducted a systematic literature search using the electronic databases of Google Scholar, MEDLINE (PubMed), WHO Virtual Health Library, and ScienceDirect, without limitations regarding gender, geographical area, race or publication date, up until December 13, 2021. Primary outcomes measured were mortality, intensive care unit (ICU) admission, assisted ventilation need, and length of hospital stay (LOS). Secondary outcome was the mechanism underlying hyponatremia among COVID-19 patients.

Results

From a total of 52 included studies, 23 underwent quantitative analysis. For the primary outcomes; proportions, odds ratios (OR), and standardized mean difference (SMD) were calculated using random effects model. The prevalence of hyponatremia was found to be 25.8%. Hyponatremia was found to be significantly associated with increased odds for mortality (OR = 1.97[95% CI, 1.50-2.59]), ICU admission (OR = 1.91 [95% CI, 1.56-2.35]), assisted ventilation need (OR = 2.04 [95% CI, 1.73-2.38]), and with increased LOS (SMD of 5.74 h [95% CI, 0.092-0.385]). Regarding the mechanisms underlying hyponatremia, syndrome of inappropriate anti-diuretic hormone secretion (SIADH) was most commonly reported, followed by adrenal insufficiency, and finally hypovolemic hyponatremia due to gastrointestinal losses.

Conclusion

Hyponatremia among COVID-19 patients is generally associated with poor outcomes, with SIADH being the most common underlying mechanism.

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.

Predictors and outcome of hyponatremia in patients with COVID 19: a single-center experience

Introduction/Aim: Hyponatremia (serum sodium 0.001) were the independent predictors of hyponatremia at the time of admission. The median length of hospital stay (LOS) was longer in patients with hyponatremia than patients with normonatremia (10 days vs. 8 days, p < 0.001). In multivariate analysis, hyponatremia was significantly associated with ICU admission or the need for mechanical ventilation (adjusted OR, 1.72; 95% confidence interval [95% CI], 1.03 to 2.85; p = 0.036). The severity of pneumonia, hemoglobin and lactate dehydrogenase levels, neutrophil-to-lymphocyte ratio (NLR), and body temperature were also associated with ICU admission or the need for mechanical ventilation. The oxygen saturation, male sex, serum albumin, NLR, and the ICU admission but not the hyponatremia on admission were significantly related to mortality. Conclusion: Hyponatremia on admission, even when mild, predicts a worse outcome in COVID-19 patients, and it should be considered in risk stratification.

Renal Manifestations and their Association with Mortality and Length of Stay in COVID-19 Patients at a Safety-net Hospital

Background

Renal involvement in COVID-19 leads to severe disease and higher mortality. We study renal parameters in COVID-19 patients and their association with mortality and length of stay in hospital.

Methods

A retrospective study (n=340) of confirmed COVID-19 patients with renal involvement determined by the presence of acute kidney injury. Multivariate analyses of logistic regression for mortality and linear regression for length of stay (LOS) adjusted for relevant demographic, comorbidity, disease severity, and treatment covariates.

Results

Mortality was 54.4% and mean LOS was 12.9 days. For mortality, creatinine peak (OR:35.27, 95% CI:2.81, 442.06, p<0.01) and persistent renal involvement at discharge (OR:4.47, 95% CI:1.99,10.06, p<0.001) were each significantly associated with increased odds for mortality. Increased blood urea nitrogen peak (OR:0.98, 95%CI:0.97,0.996, p<0.05) was significantly associated with decreased odds for mortality. For LOS, increased blood urea nitrogen peak (B:0.001, SE:<0.001, p<0.01), renal replacement therapy (B:0.19, SE:0.06, p<0.01), and increased days to acute kidney injury (B:0.19, SE:0.05, p<0.001) were each significantly associated with increased length of stay.

Conclusion

Our study emphasizes the importance in identifying renal involvement parameters in COVID-19 patients. These parameters are associated with LOS and mortality, and may assist clinicians to prognosticate COVID-19 patients with renal involvement.

COVID-19, Cation Dysmetabolism, Sialic Acid, CD147, ACE2, Viroporins, Hepcidin and Ferroptosis: A Possible Unifying Hypothesis

Background: iron and calcium dysmetabolism, with hyperferritinemia, hypoferremia, hypocalcemia and anemia have been documented in the majority of COVID-19 patients at later/worse stages. Furthermore, complementary to ACE2, both sialic acid (SA) molecules and CD147 proved relevant host receptors for SARS-CoV-2 entry, which explains the viral attack to multiple types of cells, including erythrocytes, endothelium and neural tissue. Several authors advocated that cell ferroptosis may be the core and final cell degenerative mechanism. Methods: a literature research was performed in several scientific search engines, such as PubMed Central, Cochrane Library, Chemical Abstract Service. More than 500 articles were retrieved until mid-December 2021, to highlight the available evidence about the investigated issues. Results: based on COVID-19 literature data, we have highlighted a few pathophysiological mechanisms, associated with virus-based cation dysmetabolism, multi-organ attack, mitochondria degeneration and ferroptosis. Our suggested elucidated pathological sequence is: a) spike protein subunit S1 docking with sialylated membrane glycoproteins/receptors (ACE2, CD147), and S2 subunit fusion with the lipid layer; b) cell membrane morpho-functional changes due to the consequent electro-chemical variations and viroporin action, which induce an altered ion channel function and intracellular cation accumulation; c) additional intracellular iron concentration due to a deregulated hepcidin-ferroportin axis, with higher hepcidin levels. Viral invasion may also affect erythrocytes/erythroid precursors, endothelial cells and macrophages, through SA and CD147 receptors, with relative hemoglobin and iron/calcium dysmetabolism. AB0 blood group, hemochromatosis, or environmental elements may represent possible factors which affect individual susceptibility to COVID-19.     Conclusions: our literature analysis confirms the combined role of SA molecules, ACE2, CD147, viroporins and hepcidin in determining the cation dysmetabolism and final ferroptosis in the cells infected by SARS-CoV-2. The altered ion channels and electrochemical gradients of the cell membrane have a pivotal role in the virus entry and cell dysmetabolism, with subsequent multi-organ immune-inflammatory degeneration and erythrocyte/hemoglobin alterations.

COVID-19, Cation Dysmetabolism, Sialic Acid, CD147, ACE2, Viroporins, Hepcidin and Ferroptosis: A Possible Unifying Hypothesis

Background: iron and calcium dysmetabolism, with hyperferritinemia, hypoferremia, hypocalcemia and anemia have been documented in the majority of COVID-19 patients at later/worse stages. Furthermore, complementary to ACE2, both sialic acid (SA) molecules and CD147 proved relevant host receptors for SARS-CoV-2 entry, which explains the viral attack to multiple types of cells, including erythrocytes, endothelium and neural tissue. Several authors advocated that cell ferroptosis may be the core and final cell degenerative mechanism. Methods: a literature research was performed in several scientific search engines, such as PubMed Central, Cochrane Library, Chemical Abstract Service. More than 500 articles were retrieved until mid-December 2021, to highlight the available evidence about the investigated issues. Results: based on COVID-19 literature data, we have highlighted a few pathophysiological mechanisms, associated with virus-based cation dysmetabolism, multi-organ attack, mitochondria degeneration and ferroptosis. Our suggested elucidated pathological sequence is: a) spike protein subunit S1 docking with sialylated membrane glycoproteins/receptors (ACE2, CD147), and S2 subunit fusion with the lipid layer; b) cell membrane morpho-functional changes due to the consequent electro-chemical variations and viroporin action, which induce an altered ion channel function and intracellular cation accumulation; c) additional intracellular iron concentration due to a deregulated hepcidin-ferroportin axis, with higher hepcidin levels. Viral invasion may also affect erythrocytes/erythroid precursors, endothelial cells and macrophages, through SA and CD147 receptors, with relative hemoglobin and iron/calcium dysmetabolism. AB0 blood group, hemochromatosis, or environmental elements may represent possible factors which affect individual susceptibility to COVID-19.     Conclusions: our literature analysis confirms the combined role of SA molecules, ACE2, CD147, viroporins and hepcidin in determining the cation dysmetabolism and final ferroptosis in the cells infected by SARS-CoV-2. The altered ion channels and electrochemical gradients of the cell membrane have a pivotal role in the virus entry and cell dysmetabolism, with subsequent multi-organ immune-inflammatory degeneration and erythrocyte/hemoglobin alterations.

The management of acute and chronic hyponatraemia

Hyponatraemia is the most common electrolyte abnormality encountered in clinical practice; despite this, the work-up and management of hyponatraemia remain suboptimal and varies among different specialist groups. The majority of data comparing hyponatraemia treatments have been observational, up until recently. The past two years have seen the publication of several randomised control trials investigating hyponatraemia treatments, both for chronic and acute hyponatraemia. In this article, we aim to provide a background to the physiology, cause and impact of hyponatraemia and summarise the most recent data on treatments for acute and chronic hyponatraemia, highlighting their efficacy, tolerability and adverse effects.

Hyponatremia, Inflammation at Admission, and Mortality in Hospitalized COVID-19 Patients: A Prospective Cohort Study

Background: Systemic inflammation has been associated with severe coronavirus disease 2019 (COVID-19) disease and mortality. Hyponatremia can result from inflammation due to non-osmotic stimuli for vasopressin production.

Methods: We prospectively studied 799 patients hospitalized with COVID-19 between March 7 and November 7, 2020, at Hospital Posadas in Buenos Aires, Argentina in order to evaluate the association between hyponatremia, inflammation, and its impact on clinical outcomes. Admission biochemistries, high-sensitivity C-reactive protein (hsCRP), ferritin, patient demographics, and outcome data were recorded. Outcomes (within 30 days after symptoms) evaluated included ICU admission, mechanical ventilation, dialysis-requiring acute kidney injury (AKI), and in-hospital mortality. Length of hospital stay (in days) were evaluated using comprehensive data from the EHR.

Results: Hyponatremia (median Na = 133 mmol/L) was present on admission in 366 (45.8%). Hyponatremic patients had higher hsCRP (median 10.3 [IR 4.8–18.4] mg/dl vs. 6.6 [IR 1.6–14.0] mg/dl, p < 0.01) and ferritin levels (median 649 [IQR 492–1,168] ng/dl vs. 393 [IQR 156–1,440] ng/dl, p = 0.02) than normonatremic patients. Hyponatremia was associated with higher odds of an abnormal hsCRP (unadjusted OR 5.03, 95%CI: 2.52–10.03), and remained significant after adjustment for potential confounders (adjusted OR 4.70 [95%CI: 2.33–9.49], p < 0.01). Hyponatremic patients had increased mortality on unadjusted (HR 3.05, 95%CI: 2.14–4.34) and adjusted (HR 2.76, 95%CI:1.88–4.06) in Cox proportional hazard models. Crude 30-day survival was lower for patients with hyponatremia at admission (mean [SD] survival 22.1 [0.70] days) compared with patients who were normonatremic (mean [SD] survival 27.2 [0.40] days, p < 0.01).

Conclusion: Mild hyponatremia on admission is common, is associated with systemic inflammation and is an independent risk factor for hospital mortality.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier NCT04493268.

Research on SARS-COV-2 pandemic: a narrative review focused on the Italian contribution

Background

Since late 2019, a severe acute respiratory syndrome, caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has spread with overwhelming speed causing over 214 million confirmed infections and more than 4.5 million deaths worldwide. In this framework, Italy had the second highest number of SARS-CoV-2 infections worldwide, and the largest number of deaths. A global effort of both the scientific community and governments has been undertaken to stem the pandemic. The aim of this paper is to perform a narrative review of the Italian contribution to the scientific literature regarding intensive care management of patients suffering from COVID-19, being one of the first western countries to face an outbreak of SARS-CoV-2 infection.

Main body

We performed a narrative review of the literature, dedicating particular attention and a dedicated paragraph to ventilatory support management, chest imaging findings, biomarkers, possible pharmacological interventions, bacterial superinfections, prognosis and non-clinical key aspects such as communication and interaction with relatives.

Conclusions

Many colleagues, nurses and patients died leaving their families alone. To all of them, we send our thoughts and dedicate these pages.

Hyponatremia and Oxidative Stress

Hyponatremia, i.e., the presence of a serum sodium concentration ([Na+]) < 136 mEq/L, is the most frequent electrolyte imbalance in the elderly and in hospitalized patients. Symptoms of acute hyponatremia, whose main target is the central nervous system, are explained by the "osmotic theory" and the neuronal swelling secondary to decreased extracellular osmolality, which determines cerebral oedema. Following the description of neurological and systemic manifestations even in mild and chronic hyponatremia, in the last decade reduced extracellular [Na+] was associated with detrimental effects on cellular homeostasis independently of hypoosmolality. Most of these alterations appeared to be elicited by oxidative stress. In this review, we focus on the role of oxidative stress on both osmolality-dependent and -independent impairment of cell and tissue functions observed in hyponatremic conditions. Furthermore, basic and clinical research suggested that oxidative stress appears to be a common denominator of the degenerative processes related to aging, cancer progression, and hyponatremia. Of note, low [Na+] is able to exacerbate multiple manifestations of senescence and to decrease progression-free and overall survival in oncologic patients.

Prevalence, prognostic value, pathophysiology, and management of hyponatraemia in children and adolescents with COVID-19

Hyponatraemia is frequently encountered in adults with coronavirus disease 2019 (COVID-19) and is associated with poor prognosis. This review aims to describe for the first time the prevalence, aetiology, prognostic value, pathophysiology, and management of hyponatraemia in children and adolescents with COVID-19, taking into account all relevant studies published in PubMed and Cochrane Library studies until 26th September 2021. Literature search did not detect any studies evaluating the prevalence and prognostic value of sodium disorders in paediatric patients with COVID-19. A broader literature review showed a high prevalence of hyponatraemia in children with bacterial pneumonia, while some studies have reported that hyponatraemia is relatively common in Multisystem Inflammatory Syndrome in Children (MIS-C). In adults with COVID-19, an inverse association between sodium and interleukin-6 levels has been found, indicating that hyponatraemia could be used as a surrogate marker for the risk of cytokine storm and may facilitate the identification of patients who could benefit from immunomodulatory agents. Studies are urgently needed to evaluate the frequency and prognostic impact of electrolyte abnormalities in children with COVID-19. In the meantime, clinicians are urged to consider hyponatraemia in children with COVID-19 as a potential red flag, investigate the cause and administer fluids and other therapies accordingly.

Age and genotype dependent erythropoietin protection in COVID-19

Erythropoietin (EPO) is the main mediator of erythropoiesis and an important tissue protective hormone that appears to mediate an ancestral neuroprotective innate immune response mechanism at an early age. When the young brain is threatened-prematurity, neonatal hyperbilirubinemia, malaria- EPO is hyper-secreted disproportionately to any concurrent anemic stimuli. Under eons of severe malarial selection pressure, neuroprotective EPO augmenting genetic determinants such as the various hemoglobinopathies, and the angiotensin converting enzyme (ACE) I/D polymorphism, have been positively selected. When malarial and other cerebral threats abate and the young child survives to adulthood, EPO subsides. Sustained high ACE and angiotensin II (Ang II) levels through the ACE D allele in adulthood may then become detrimental as witnessed by epidemiological studies. The ubiquitous renin angiotensin system (RAS) influences the α-klotho/fibroblast growth factor 23 (FGF23) circuitry, and both are interconnected with EPO. Here we propose that at a young age, EPO augmenting genetic determinants through ACE D allele elevated Ang II levels in some or HbE/beta thalassemia in others would increase EPO levels and shield against coronavirus disease 2019, akin to protection from malaria and dengue fever. Human evolution may use ACE2 as a "bait" for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) to gain cellular entry in order to trigger an ACE/ACE2 imbalance and stimulate EPO hypersecretion using tissue RAS, uncoupled from hemoglobin levels. In subjects without EPO augmenting genetic determinants at any age, ACE2 binding and internalization upon SARS-CoV-2 entry would trigger an ACE/ACE2 imbalance, and Ang II oversecretion leading to protective EPO stimulation. In children, low nasal ACE2 Levels would beneficially augment this imbalance, especially for those without protective genetic determinants. On the other hand, in predisposed adults with the ACE D allele, ACE/ACE2 imbalance, may lead to uncontrolled RAS overactivity and an Ang II induced proinflammatory state and immune dysregulation, with interleukin 6 (IL-6), plasminogen activator inhibitor, and FGF23 elevations. IL-6 induced EPO suppression, aggravated through co-morbidities such as hypertension, diabetes, obesity, and RAS pharmacological interventions may potentially lead to acute respiratory distress syndrome, cytokine storm and/or autoimmunity. HbE/beta thalassemia carriers would enjoy protection at any age as their EPO stimulation is uncoupled from the RAS system. The timely use of rhEPO, EPO analogs, acetylsalicylic acid, bioactive lipids, or FGF23 antagonists in genetically predisposed individuals may counteract those detrimental effects.

Sodium alterations impair the prognosis of hospitalized patients with COVID-19 pneumonia

OBJECTIVE

Dysnatremia is common in hospitalized patients, often worsening the prognosis in pneumopathies and critical illnesses. Information on coronavirus disease-19 (COVID-19)-related hyponatremia is partially conflicting, whereas data on hypernatremia in this context are scarce. We assessed, in a cohort of COVID-19 inpatients: the prevalence of sodium alterations at admission and throughout their hospitalization; their association with inflammation/organ damage indexes; their short-term prognostic impact.

STUDY DESIGN AND METHODS

117 patients (81 males, 64 ± 13 years) hospitalized for COVID-19 between 1 March and 30 April 2020 were retrospectively followed-up for their first 21 days of stay by collecting all serum sodium measurements, basal CRP and serum lactate levels, maximum IL-6 and information on care setting, required ventilation, length of hospitalization, in-hospital death.

RESULTS

At admission, 26.5% patients had hyponatremia, and 6.8% had hypernatremia. During their hospitalization, 13.7% patients experienced both disorders ('mixed dysnatremia'). Lower sodium levels at admission were correlated with higher C reactive protein (CRP) (P = 0.039) and serum lactate levels (P = 0.019), but not interleukin-6 (IL-6). Hypernatremia and a wider sodium variability were associated with maximum required ventilation, need for ICU assistance and duration of the hospitalization. Mean estimated time to Intensive Care Unit (ICU) admission was 20 days shorter in patients exposed to sodium alterations at any time of their hospital course (log-rank test P = 0.032).

CONCLUSIONS

Sodium alterations frequently affect hospitalized COVID-19 patients. Hyponatremia could indicate pulmonary involvement, whereas hypernatremia is associated to prolonged hospitalization and the need for intensive care/mechanical ventilation, particularly when resulting from prior hyponatremia. Optimizing in-hospital sodium balance is crucial to improve patients' prognosis.

Potential Use of Pharmacogenetics to Reduce Drug-Induced Syndrome of Inappropriate Antidiuretic Hormone (SIADH)

Syndrome of inappropriate antidiuretic hormone (SIADH) is a common cause of hyponatremia, and many cases represent adverse reactions to drugs that alter ion channel conductance within the peptidergic nerve terminals of the posterior pituitary. The frequency of drug-induced SIADH increases with age; as many as 20% of patients residing in nursing homes have serum sodium levels below 135 mEq/L. Mild hyponatremia is associated with cognitive changes, gait instability, and falls. Severe hyponatremia is associated with cerebral edema, seizures, permanent disability, and/or death. Although pharmacogenetic tests are now being deployed for some drugs capable of causing SIADH (e.g., antidepressants, antipsychotics, and opioid analgesics), the implementation of these tests has been based upon the prior known association of these drugs with other serious adverse drug reactions (e.g., electrocardiographic abnormalities). Work is needed in large observational cohorts to quantify the strength of association between pharmacogene variants and drug-induced SIADH so that decision support can be developed to identify patients at high risk.

ENDOCRINOLOGY IN THE TIME OF COVID-19-2021 UPDATES: The management of diabetes insipidus and hyponatraemia

COVID-19 has changed the nature of medical consultations, emphasizing virtual patient counselling, with relevance for patients with diabetes insipidus (DI) or hyponatraemia. The main complication of desmopressin treatment in DI is dilutional hyponatraemia. Since plasma sodium monitoring is not always possible in times of COVID-19, we recommend to delay the desmopressin dose once a week until aquaresis occurs allowing excess retained water to be excreted. Patients should measure their body weight daily. Patients with DI admitted to the hospital with COVID-19 have a high risk for mortality due to volume depletion. Specialists must supervise fluid replacement and dosing of desmopressin. Patients after pituitary surgery should drink to thirst and measure their body weight daily to early recognize the development of postoperative SIAD. They should know hyponatraemia symptoms. Hyponatraemia in COVID-19 is common with a prevalence of 20-30% and is mostly due to SIAD or hypovolaemia. It mirrors disease severity and is an early predictor of mortality. Hypernatraemia may also develop in COVID-19 patients, with a prevalence of 3-5%, especially in ICU, and derives from different multifactorial reasons, for example, due to insensible water losses from pyrexia, increased respiration rate and use of diuretics. Hypernatraemic dehydration may contribute to the high risk of acute kidney injury in COVID-19. IV fluid replacement should be administered with caution in severe cases of COVID-19 because of the risk of pulmonary oedema.