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.

Epidemiology and Outcomes of Hypernatraemia in Patients with COVID-19-A Territory-Wide Study in Hong Kong.

BACKGROUND: Dysnatraemias are commonly reported in COVID-19. However, the clinical epidemiology of hypernatraemia and its impact on clinical outcomes in relation to different variants of SARS-CoV-2, especially the prevailing Omicron variant, remain unclear. METHODS: This was a territory-wide retrospective study to investigate the clinical epidemiology and outcomes of COVID-19 patients with hypernatraemia at presentation during the period from 1 January 2020 to 31 March 2022. The primary outcome was 30-day mortality. Key secondary outcomes included rates of hospitalization and ICU admission, and costs of hospitalization. RESULTS: In this study, 53,415 adult COVID-19 patients were included for analysis. Hypernatraemia was observed in 2688 (5.0%) patients at presentation, of which most cases (99.2%) occurred during the local "5th wave" dominated by the Omicron BA.2 variant. Risk factors for hypernatraemia at presentation included age, institutionalization, congestive heart failure, dementia, higher SARS-CoV-2 Ct value, white cell count, C-reactive protein and lower eGFR and albumin levels (p < 0.001 for all). Patients with hypernatraemia showed significantly higher 30-day mortality (32.0% vs. 5.7%, p < 0.001) and longer lengths of stay (12.9 ± 10.9 vs. 11.5 ± 12.1 days, p < 0.001) compared with those with normonatraemia. Multivariate analysis revealed hypernatraemia at presentation as an independent predictor for 30-day mortality (aHR 1.32, 95% CI 1.14-1.53, p < 0.001) and prolonged hospital stays (OR 1.55, 95% CI 1.17-2.05, p = 0.002). CONCLUSIONS: Hypernatraemia is common among COVID-19 patients, especially among institutionalized older adults with cognitive impairment and other comorbidities during large-scale outbreaks during the Omicron era. Hypernatraemia is associated with unfavourable outcomes and increased healthcare utilization.

Epidemiology and outcomes of hyponatremia in patients with COVID-19-A territory-wide study in Hong Kong.

Background: Hyponatremia is common in COVID-19, but its epidemiology and impact on clinical outcomes in relation to different variants, especially the Omicron variant, requires further clarification. Methods: This was a territory-wide retrospective study to investigate the epidemiology and outcomes of COVID-19 patients with hyponatremia from January 1, 2020 to March 31, 2022 in Hong Kong. The primary outcome was 30-day mortality of patients with COVID-19 and hyponatremia at presentation. Secondary outcomes included rate of hospitalization, intensive care unit (ICU) hospitalization, overall duration of hospitalization, and duration of ICU hospitalization. Results: A total of 53,415 COVID-19 patients were included for analysis, of which 14,545 (27.2%) had hyponatremia at presentation. 9813 (67.5%), 2821 (19.4%), and 1911 (13.1%) had mild (130 to <135 mmol/L), moderate (125 to <130 mmol/L), and severe hyponatremia (<125 mmol/L) at presentation respectively. Age, male sex, diabetes, active malignancy, white cell count, serum creatinine, hypoalbuminemia, C-reactive protein, and viral loads were independent predictors for hyponatremia in COVID-19 patients (P < 0.001, for all). Hyponatremic patients had increased 30-day mortality (9.7 vs. 5.7%, P < 0.001), prolonged hospitalization (11.9 ± 15.1 days vs. 11.5 ± 12.1 days, P < 0.001), and more ICU admissions (7.0% vs. 3.3%, P < 0.001). Patients diagnosed during the "fifth wave" Omicron BA.2 outbreak had 2.29-fold risk (95% CI 2.02-2.59, P < 0.001) of presenting with hyponatremia compared to other waves. Conclusion: Hyponatremia is common among COVID-19 patients, and may serve as a prognostic indicator for unfavorable outcomes and increased healthcare utilization in the evolving COVID-19 outbreak.