Hydroelectrolytic Disorder in COVID-19 patients: Evidence Supporting the Involvement of Subfornical Organ and Paraventricular Nucleus of the Hypothalamus.

Multiple neurological problems have been reported in coronavirus disease-2019 (COVID-19) patients because severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) likely spreads to the central nervous system (CNS) via olfactory nerves or through the subarachnoid space along olfactory nerves into the brain's cerebrospinal fluid and then into the brain's interstitial space. We hypothesize that SARS-CoV-2 enters the subfornical organ (SFO) through the above routes and the circulating blood since circumventricular organs (CVOs) such as the SFO lack the blood-brain barrier, and infection of the SFO causes dysfunction of the hypothalamic paraventricular nucleus (PVN) and supraoptic nucleus (SON), leading to hydroelectrolytic disorder. SARS-CoV-2 can readily enter SFO-PVN-SON neurons because these neurons express angiotensin-converting enzyme-2 receptors and proteolytic viral activators, which likely leads to neurodegeneration or neuroinflammation in these regions. Considering the pivotal role of SFO-PVN-SON circuitry in modulating hydroelectrolyte balance, SARS-CoV-2 infection in these regions could disrupt the neuroendocrine control of hydromineral homeostasis. This review proposes mechanisms by which SARS-CoV-2 infection of the SFO-PVN-SON pathway leads to hydroelectrolytic disorder in COVID-19 patients.

Renal complications in COVID-19: a systematic review and meta-analysis.

PURPOSE: Emerging data suggest that coronavirus disease 2019 (COVID-19) has extrapulmonary manifestations but its renal manifestations are not clearly defined. We aimed to evaluate renal complications of COVID-19 and their incidence using a systematic meta-analysis. DESIGN: Observational studies reporting renal complications in COVID-19 patients were sought from MEDLINE, Embase and the Cochrane Library from 2019 to June 2020. The nine-star Newcastle-Ottawa Scale was used to evaluate methodological quality. Incidence with 95% confidence intervals (CIs) were pooled using random-effects models. RESULTS: We included 22 observational cohort studies comprising of 17,391 COVID-19 patients. Quality scores of studies ranged from 4 to 6. The pooled prevalence of pre-existing chronic kidney disease (CKD) and end-stage kidney disease was 5.2% (2.8-8.1) and 2.3% (1.8-2.8), respectively. The pooled incidence over follow-up of 2-28 days was 12.5% (10.1-15.0) for electrolyte disturbance (e.g. hyperkalaemia), 11.0% (7.4-15.1) for acute kidney injury (AKI) and 6.8% (1.0-17.0) for renal replacement therapy (RRT). In subgroup analyses, there was a higher incidence of AKI in US populations and groups with higher prevalence of pre-existing CKD. CONCLUSIONS: Frequent renal complications reported among hospitalized COVID-19 patients are electrolyte disturbance, AKI and RRT. Aggressive monitoring and management of these renal complications may help in the prediction of favourable outcomes. Systematic review registration: PROSPERO 2020: CRD42020186873 KEY MESSAGES COVID-19 affects multiple organs apart from the respiratory system; however, its renal manifestations are not clearly defined. In this systematic meta-analysis of 22 observational cohort studies, the prevalence of pre-existing chronic kidney disease (CKD) in COVID-19 patients was 5.2%. The most frequent renal complication was electrolyte disturbance (particularly hyperkalaemia) with an incidence of 12.5% followed by acute kidney injury (AKI) with an incidence of 11.0%; US populations and groups with higher prevalence of CKD had higher incidence of AKI.

Extracellular Water to Total Body Water Ratio in Viral Liver Diseases: A Study Using Bioimpedance Analysis.

AIMS: To investigate the relationship between extracellular water to total body water ratio (ECW/TBW) in bioimpedance analysis (BIA) and clinical parameters in hepatitis viruses related to liver diseases. METHODS: ECW/TBW was compared in patients with hepatitis B virus (HBV, n = 85) and hepatitis C virus (HCV, n = 440) related liver diseases. We also examined factors linked to mild to severe overhydrated state (ECW/TBW ≥0.4). RESULTS: The median ECW/TBW in the HCV group was 0.388 (range, 0.365⁻0.433), while that in the HBV group was 0.381 (range, 0.363⁻0.425) (p < 0.0001). In all cases (n = 525), for predicting F3 or more, ECW/TBW yielded the area under the receiver operating characteristics (AUROC, 0.74912) and for predicting F4, ECW/TBW yielded the AUROC (0.75517). Multivariate analysis showed that age, prothrombin time, serum albumin, and alanine aminotransferase were significant factors linked to ECW/TBW ≥0.4. In patients with FIB-4 index <2, ECW/TBW in the HCV group was significantly higher than that in the HBV group (p = 0.0188), while in patients with 2 ≤ FIB-4 index <4 and FIB-4 index ≥4, the difference in the two groups did not reach significance. CONCLUSION: ECW/TBW can be different according to hepatitis viruses. Overhydrated status can easily occur in the HCV group even in the non-LC status compared with the HBV group.

ELECTROLYTE DISTURBANCE AND KIDNEY DYSFUNCTION IN DENGUE VIRAL INFECTION.

Dengue virus infection (DVI) is endemic in tropical countries in both children and adults. The classical presentation includes fever, hepatomegaly, thrombocytopenia-related bleeding disorders, and plasma leakage. Multi-organ involvement, including kidneys is found in complex cases. Asymptomatic electrolyte disturbances, abnormal urinalysis, and more severe manifestation such as acute kidney injury (AKI) usually indicate kidney involvement. Such manifestations are not rare in DVI, but are often not recognized and can cause the physician to misread the real situation of the patient. The prevalence of electrolyte disturbances or kidney involvement reported in studies varies widely by country and mainly depends on the severity of DVI and age of the patients. The prevalence of DVI-induced AKI ranges from 0.2%-10.0% in children and 2.2%-35.7% in adults. The prevalence among all age groups appears to be increasing in the last decade. Dengue shock syndrome (DSS) has been reported to be an independent risk factor for AKI development. The mechanism of DVI-induced AKI is complex and the details are to date undetermined. Urinalysis, serum electrolytes and creatinine measurements should be performed to document renal involvement in DVI patients for early detection and initiation of appropriate fluid therapy with close monitoring. Renal replacement therapy may be required in some cases. The presence of AKI dramatically increases the mortality rate among both childhood and adulthood DVI from 12%-44% to more than 60%.

Cyprinid herpesvirus-3 (CyHV-3) disturbs osmotic balance in carp (Cyprinus carpio L.)--A potential cause of mortality.

Cyprinid herpesvirus-3 (CyHV-3) causes a fatal disease in carp (Cyprinus carpio) and its ornamental koi varieties which seriously affects production and trade of this fish species globally. Up to now, the pathophysiology of this disease remains unclear. Affected individuals develop most prominent lesions in gills, skin and kidney, in tissues which are involved in the osmotic regulation of freshwater teleosts. Therefore, here serum and urine electrolyte levels were examined during the course of an experimental infection of carp with CyHV-3. In infected carp an interstitial nephritis with a progressive deterioration of nephric tubules developed, which was paralleled by elevated electrolyte losses, mainly Na(+) in the urine. The urine/plasma ratio for Na(+) increased from 0.03 in uninfected carp to 0.43-0.83 in carp under CyHV-3 infection, while concentration of divalent ions were not significantly changed. These electrolyte losses could not be compensated since plasma osmolality and Na(+) concentration dropped significantly in CyHV-3 infected carp. This was most probably caused by the progressive deterioration of the branchial epithelium, which in teleosts plays a prominent role in osmoregulation, and which was seen concomitantly with decreasing electrolyte levels in the serum of carp under CyHV-3 infection. Immediately after infection with CyHV-3, by day 2 post exposure, affected carp showed severe anaemia and prominent leucocytosis indicating the development of an acute inflammation, which could intensify the observed hydro-mineral imbalances. The data presented here show that an infection with CyHV-3 induces an acute inflammation and a severe dysfunction of osmoregulation in affected carp or koi, which may lead to death in particular in the case of acute disease progression.

Renal disorders in HIV-infected patients.

BACKGROUND: HIV infection affects all body organs including kidney. Since the frequency of HIV-related renal disorders is unknown in Iran and the number of HIV-infected patients is increasing, this study was conducted for the first time in Iran to assess the frequency of electrolyte imbalance, renal failure, and proteinuria among HIV-infected patients. METHODS: Between April and December 2005, 65 HIV-infected patients who were receiving care at an outpatient counseling center in Tehran, participated in this study. Blood samples were collected to measure serum levels of sodium, potassium, calcium, phosphorus, blood urea nitrogen, and creatinine. Urine samples were analyzed to detect protein, red blood cells, white blood cells, and cast. RESULTS: Of the 65 HIV-infected patients, 86.2% were males. The mean age of the patients was 37+/-8.7 years, and 58.5% of the patients had a history of injecting illicit drugs. Urinalysis was normal in all patients, and serum levels of electrolytes, blood urea nitrogen, and creatinine were all in normal range. CONCLUSION: We found no electrolyte imbalance, proteinuria, or renal failure in HIV-infected patients. It seems that renal disorder is infrequent in Iranian HIV-infected patients.