COVID-19 and Kidney Disease

Lingering effects of COVID-19 in the care of perioperative patients

PURPOSE OF REVIEW

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can lead to organ dysfunction and clinical symptoms beyond the acute infection phase. These effects may have significant implications for the management of perioperative patients. The purpose of this article is to provide a systems-based approach to the subacute and chronic effects of SARS-CoV-2 that are most relevant to anesthesiology practice.

RECENT FINDINGS

In 2024, COVID-19 remains a concern for anesthesiologists due ongoing new infections, evolving viral strains, and relatively low rates of booster vaccination in the general population. A growing body of literature describes the post-COVID-19 syndrome in which patients experience symptoms more than 12 weeks after acute infection. Recent literature describes the lingering effects of SARS-CoV-2 infection on all major organ systems, including neurologic, pulmonary, cardiovascular, renal, hematologic, and musculoskeletal, and suggests an increased perioperative mortality risk in some populations.

SUMMARY

This review offers anesthesiologists an organ system-based approach to patients with a history of COVID-19. Recognizing the long-term sequelae of SARS-CoV-2 infection can help anesthesiologists to better evaluate perioperative risk, anticipate clinical challenges, and thereby optimize patient care.

Association of nirmatrelvir-ritonavir with post-acute sequelae and mortality in patients admitted to hospital with COVID-19: a retrospective cohort study

BACKGROUND

Studies have established the short-term efficacy of nirmatrelvir-ritonavir in managing COVID-19, yet its effect on post-COVID-19 condition, especially in patients admitted to hospital, remains understudied. This study aimed to examine the effect of nirmatrelvir-ritonavir on post-COVID-19 condition among patients admitted to hospital in Hong Kong.

METHODS

This retrospective cohort study used real-world, territory-wide inpatient records, vaccination records, and confirmed COVID-19 case data from the Hong Kong Hospital Authority and Department of Health, The Government of the Hong Kong Special Administrative Region. Patients aged 18 years and older who tested positive for SARS-CoV-2 between March 11, 2022, and Oct 10, 2023, and who were admitted to hospital with COVID-19 were included. The treatment group included patients prescribed nirmatrelvir-ritonavir within 5 days of symptom onset, excluding those prescribed molnupiravir within 21 days, and the control group had no exposure to either nirmatrelvir-ritonavir or molnupiravir. The outcomes were post-acute inpatient death and 13 sequelae (congestive heart failure, atrial fibrillation, coronary artery disease, deep vein thrombosis, chronic pulmonary disease, acute respiratory distress syndrome, interstitial lung disease, seizure, anxiety, post-traumatic stress disorder, end-stage renal disease, acute kidney injury, and pancreatitis). These outcomes were evaluated starting at 21 days after the positive RT-PCR date in each respective cohort constructed for the outcome. Standardised mortality ratio weights were applied to balance covariates, and Cox proportional hazards regression was used to investigate the relationship between nirmatrelvir-ritonavir and outcomes.

FINDINGS

136 973 patients were screened for inclusion, among whom 50 055 were eligible and included in the analysis (24 873 [49·7%] were female and 25 182 [50·3%] were male). 15 242 patients were prescribed nirmatrelvir-ritonavir during acute COVID-19 and 23 756 patients were included in the control group; 11 057 patients did not meet our definition for the exposed and unexposed groups. Patients were followed up for a median of 393 days (IQR 317-489). In the nirmatrelvir-ritonavir group compared with the control group, there was a significantly lower hazard of post-acute inpatient death (hazard ratio 0·62 [95% CI 0·57-0·68]; p<0·0001), congestive heart failure (0·70 [0·58-0·85]; p=0·0002), atrial fibrillation (0·63 [0·52-0·76]; p<0·0001), coronary artery disease (0·71 [0·59-0·85]; p=0·0002), chronic pulmonary disease (0·68 [0·54-0·86]; p=0·0011), acute respiratory distress syndrome (0·71 [0·58-0·86]; p=0·0007), interstitial lung disease (0·17 [0·04-0·75]; p=0·020), and end-stage renal disease (0·37 [0·18-0·74]; p=0·0049). There was no evidence indicating difference between the groups in deep vein thrombosis, seizure, anxiety, post-traumatic stress disorder, acute kidney injury, and pancreatitis.

INTERPRETATION

This study showed extended benefits of nirmatrelvir-ritonavir for reducing the risk of post-acute inpatient death as well as cardiovascular and respiratory complications among patients admitted to hospital with COVID-19. Further research is essential to uncover the underlying mechanisms responsible for these observed negative associations and to devise effective strategies for preventing the onset of post-acute sequelae.

FUNDING

Health and Medical Research Fund, Research Grants Council theme-based research schemes, and Research Grants Council Collaborative Research Fund.

Kidney Function Tests and Continuous eGFR Decrease at Six Months after SARS-CoV-2 Infection in Patients Clinically Diagnosed with Post-COVID Syndrome

The long-term sequelae of SARS-CoV-2 infection are still under research, since extensive studies showed plenty of systemic effects of the viral infection, extending even after the acute phase of the infection. This study evaluated kidney function tests six months after SARS-CoV-2 infection in patients clinically diagnosed with Post-COVID Syndrome, hypothesizing persistent renal dysfunction evidenced by altered kidney function tests compared to baseline levels. Continuous eGFR decrease <30 at six months post-infection was considered the main study outcome. Conducted at the "Victor Babes" Hospital, this retrospective observational study involved adults with laboratory-confirmed SARS-CoV-2 infection and clinically-diagnosed Post-COVID Syndrome, excluding those with prior chronic kidney disease or significant renal impairment. Kidney function tests, including serum creatinine, blood urea nitrogen (BUN), estimated glomerular filtration rate (eGFR), alongside markers of kidney damage such as proteinuria and hematuria, were analyzed. Among 206 participants, significant differences were observed between the control (n = 114) and the Post-COVID group (n = 92). The Post-COVID group exhibited higher serum creatinine (109.7 μmol/L vs. 84.5 μmol/L, p < 0.001), lower eGFR (65.3mL/min/1.73 m2 vs. 91.2 mL/min/1.73 m2, p < 0.001), and elevated BUN levels (23.7 mg/dL vs. 15.2 mg/dL, p < 0.001) compared to the control group. Regression analysis highlighted significant predictors of continuous eGFR decrease <30 at six months post-infection. The development of acute kidney injury (AKI) during the initial COVID-19 illness emerged as a strong predictor of reduced eGFR (β = 3.47, p < 0.001). Additional factors, including a creatinine increase (23 μmol/L above the normal range) and an elevated Albumin to Creatinine Ratio (ACR) (>11 mg/g above the normal range), were significantly associated with eGFR reduction. Patients with Post-COVID Syndrome demonstrate significant renal impairment six months post-SARS-CoV-2 infection. The study's findings stress the need for ongoing monitoring and intervention strategies for renal health in affected individuals, underscoring the persistent impact of COVID-19 on renal function.

Vascular Alterations Following COVID-19 Infection: A Comprehensive Literature Review

SARS-CoV-2, the causative agent of the ongoing COVID-19 pandemic, has revealed a broader impact beyond the respiratory system, predominantly affecting the vascular system with various adverse manifestations. The infection induces endothelial dysfunction and immune system dysregulation, creating an inflammatory and hypercoagulable state. It affects both microvasculature and macrovasculature, leading to thromboembolic events, cardiovascular manifestations, impaired arterial stiffness, cerebrovascular complications, and nephropathy, as well as retinopathy-frequently observed in cases of severe illness. Evidence suggests that SARS-CoV-2 infection may result in persistent effects on the vascular system, identified as long-term COVID-19. This is characterized by prolonged inflammation, endotheliopathy, and an increased risk of vascular complications. Various imaging modalities, histopathological studies, and diagnostic tools such as video capillaroscopy and magnetic resonance imaging have been employed to visualize vascular alterations. This review aims to comprehensively summarize the evidence concerning short and long-term vascular alterations following COVID-19 infection, investigating their impact on patients' prognosis, and providing an overview of preventive strategies to mitigate associated vascular complications.

Clinical characteristics and outcomes in COVID-19 in kidney transplant recipients: a propensity score matched cohort study

Patients with chronic kidney disease (CKD), especially those on dialysis or who have received a kidney transplant (KT), are considered more vulnerable to severe COVID-19. This susceptibility is attributed to advanced age, a higher frequency of comorbidities, and the chronic immunosuppressed state, which may exacerbate their susceptibility to severe outcomes. Therefore, our study aimed to compare the clinical characteristics and outcomes of COVID-19 in KT patients with those on chronic dialysis and non-CKD patients in a propensity score-matched cohort study. This multicentric retrospective cohort included adult COVID-19 laboratory-confirmed patients admitted from March/2020 to July/2022, from 43 Brazilian hospitals. The primary outcome was in-hospital mortality. Propensity score analysis matched KT recipients with controls - patients on chronic dialysis and those without CKD (within 0.25 standard deviations of the logit of the propensity score) - according to age, sex, number of comorbidities, and admission year. This study included 555 patients: 163 KT, 146 on chronic dialysis, and 249 non-CKD patients (median age 57 years, 55.2% women). With regards to clinical outcomes, chronic dialysis patients had a higher prevalence of acute heart failure, compared to KT recipients, furthermore, both groups presented high in-hospital mortality, 34.0 and 28.1%, for KT and chronic dialysis patients, respectively. When comparing KT and non-CKD patients, the first group had a higher incidence of in-hospital dialysis (26.4% vs. 8.8%, p < 0.001), septic shock (24.1% vs. 12.0%, p = 0.002), and mortality (32.5% vs. 23.3%, p = 0.039), in addition to longer time spent in the intensive care unit (ICU). In this study, chronic dialysis patients presented a higher prevalence of acute heart failure, compared to KT recipients, whereas KT patients had a higher frequency of complications than those without CKD, including septic shock, dialysis during hospitalization, and in-hospital mortality as well as longer time spent in the ICU.

Co-Expression of Niemann-Pick Type C1-Like1 (NPC1L1) with ACE2 Receptor Synergistically Enhances SARS-CoV-2 Entry and Fusion

The entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into human embryonic kidney (HEK293T) cells has been shown to be a cholesterol-rich, lipid raft-dependent process. In this study, we investigated if the presence of a cholesterol uptake receptor Niemann-pick type c1-like1 (NPC1L1) impacts SARS-CoV-2 cell entry. Initially, we utilized reporter-based pseudovirus cell entry assays and a spike (S) glycoprotein-mediated cell-to-cell fusion assay. Using Chinese hamster ovary (CHO-K1) cells, which lack endogenous receptors for SARS-CoV-2 entry, our data showed that the co-expression of NPC1L1 together with the ACE2 receptor synergistically increased SARS-CoV-2 pseudovirus entry even more than the cells expressing ACE-2 receptor alone. Similar results were also found with the HEK293T cells endogenously expressing the ACE2 receptor. Co-cultures of effector cells expressing S glycoprotein together with target cells co-expressing ACE-2 receptor with NPC1L1 significantly promoted quantitative cell-to-cell fusion, including syncytia formation. Finally, we substantiated that an elevated expression of NPC1L1 enhanced entry, whereas the depletion of NPC1L1 resulted in a diminished SARS-CoV-2 entry in HEK293T-ACE2 cells using authentic SARS-CoV-2 virus in contrast to their respective control cells. Collectively, these findings underscore the pivotal role of NPC1L1 in facilitating the cellular entry of SARS-CoV-2. Importance: Niemann-Pick type C1-like1 (NPC1L1) is an endosomal membrane protein that regulates intracellular cholesterol trafficking. This protein has been demonstrated to play a crucial role in the life cycle of several clinically important viruses. Although SARS-CoV-2 exploits cholesterol-rich lipid rafts as part of its viral entry process, the role of NPC1L1 in SARS-CoV-2 entry remains unclear. Our research represents the first-ever demonstration of NPC1L1's involvement in facilitating SARS-CoV-2 entry. The observed role of NPC1L1 in human kidney cells is not only highly intriguing but also quite relevant. This relevance stems from the fact that NPC1L1 exhibits high expression levels in several organs, including the kidneys, and the fact that kidney damages are reported during severe cases of SARS-CoV-2. These findings may help us understand the new functions and mechanisms of NPC1L1 and could contribute to the identification of new antiviral targets.

Glomerulonephritis following COVID-19 infection or vaccination: a multicenter study in South Korea

BACKGROUND

Despite the widespread impact of the severe acute respiratory syndrome coronavirus 2 (coronavirus disease 2019, COVID-19) and vaccination in South Korea, our understanding of kidney diseases following these events remains limited. We aimed to address this gap by investigating the characteristics of glomerular diseases following the COVID-19 infection and vaccination in South Korea.

METHODS

Data from multiple centers were used to identify de novo glomerulonephritis (GN) cases with suspected onset following COVID-19 infection or vaccination. Retrospective surveys were used to determine the COVID-19-related histories of patients who were initially not implicated. Bayesian structural time series and autoregressive integrated moving average models were used to determine causality.

RESULTS

Glomerular diseases occurred shortly after the infection or vaccination. The most prevalent postinfection GN was podocytopathy (42.9%), comprising primary focal segmental glomerulosclerosis and minimal change disease, whereas postvaccination GN mainly included immunoglobulin A nephropathy (IgAN; 57.9%) and Henoch-Schönlein purpura nephritis (HSP; 15.8%). No patient progressed to end-stage kidney disease. Among the patients who were initially not implicated, nine patients with IgAN/HSP were recently vaccinated against COVID-19. The proportion of glomerular diseases changed during the pandemic in South Korea, with an increase in acute interstitial nephritis and a decrease in pauci-immune crescentic GN.

CONCLUSION

This study showed the characteristics of GNs following COVID-19 infection or vaccination in South Korea. Understanding these associations is crucial for developing effective patient management and vaccination strategies. Further investigation is required to fully comprehend COVID-19's impact on GN.

SARS-CoV-2 and its Multifaceted Impact on Bone Health: Mechanisms and Clinical Evidence

PURPOSE OF REVIEW

SARS-CoV-2 infection, the culprit of the COVID-19 pandemic, has been associated with significant long-term effects on various organ systems, including bone health. This review explores the current understanding of the impacts of SARS-CoV-2 infection on bone health and its potential long-term consequences.

RECENT FINDINGS

As part of the post-acute sequelae of SARS-CoV-2 infection, bone health changes are affected by COVID-19 both directly and indirectly, with multiple potential mechanisms and risk factors involved. In vitro and preclinical studies suggest that SARS-CoV-2 may directly infect bone marrow cells, leading to alterations in bone structure and osteoclast numbers. The virus can also trigger a robust inflammatory response, often referred to as a "cytokine storm", which can stimulate osteoclast activity and contribute to bone loss. Clinical evidence suggests that SARS-CoV-2 may lead to hypocalcemia, altered bone turnover markers, and a high prevalence of vertebral fractures. Furthermore, disease severity has been correlated with a decrease in bone mineral density. Indirect effects of SARS-CoV-2 on bone health, mediated through muscle weakness, mechanical unloading, nutritional deficiencies, and corticosteroid use, also contribute to the long-term consequences. The interplay of concurrent conditions such as diabetes, obesity, and kidney dysfunction with SARS-CoV-2 infection further complicates the disease's impact on bone health. SARS-CoV-2 infection directly and indirectly affects bone health, leading to potential long-term consequences. This review article is part of a series of multiple manuscripts designed to determine the utility of using artificial intelligence for writing scientific reviews.

COVID-19 and Bone Loss: A Review of Risk Factors, Mechanisms, and Future Directions

PURPOSE OF REVIEW

SARS-CoV-2 drove the catastrophic global phenomenon of the COVID-19 pandemic resulting in a multitude of systemic health issues, including bone loss. The purpose of this review is to summarize recent findings related to bone loss and potential mechanisms.

RECENT FINDINGS

The early clinical evidence indicates an increase in vertebral fractures, hypocalcemia, vitamin D deficiencies, and a loss in BMD among COVID-19 patients. Additionally, lower BMD is associated with more severe SARS-CoV-2 infection. Preclinical models have shown bone loss and increased osteoclastogenesis. The bone loss associated with SARS-CoV-2 infection could be the result of many factors that directly affect the bone such as higher inflammation, activation of the NLRP3 inflammasome, recruitment of Th17 cells, the hypoxic environment, and changes in RANKL/OPG signaling. Additionally, SARS-CoV-2 infection can exert indirect effects on the skeleton, as mechanical unloading may occur with severe disease (e.g., bed rest) or with BMI loss and muscle wasting that has also been shown to occur with SARS-CoV-2 infection. Muscle wasting can also cause systemic issues that may influence the bone. Medications used to treat SARS-CoV-2 infection also have a negative effect on the bone. Lastly, SARS-CoV-2 infection may also worsen conditions such as diabetes and negatively affect kidney function, all of which could contribute to bone loss and increased fracture risk. SARS-CoV-2 can negatively affect the bone through multiple direct and indirect mechanisms. Future work will be needed to determine what patient populations are at risk of COVID-19-related increases in fracture risk, the mechanisms behind bone loss, and therapeutic options. This review article is part of a series of multiple manuscripts designed to determine the utility of using artificial intelligence for writing scientific reviews.

Nucleocapsid protein accumulates in renal tubular epithelium of a post-COVID-19 patient

IMPORTANCE

Even though the coronavirus disease 2019 (COVID-19) pandemic is slowly developing into a conventional infectious disease, the long-term effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus infection are still not well understood. One of the problems is that many COVID-19 cases develop acute kidney injuries. Still, it is heavily debated whether SARS-CoV-2 virus enters and actively replicates in kidney tissue and if SARS-CoV-2 virus particles can be detected in kidney during or post-infection. Here, we demonstrated that nucleocapsid N protein was detected in kidney tubular epithelium of patients that already recovered form COVID-19. The presence of the abundantly produced N protein without signs of viral replication could have implications for the recurrence of kidney disease and have a continuing effect on the immune system.

Anticoagulation practices for continuous renal replacement therapy: a survey of physicians from the United States

BACKGROUND

During continuous renal replacement therapy (CRRT), anticoagulants are recommended for patients at low risk of bleeding and not already receiving systemic anticoagulants. Current anticoagulants used in CRRT in the US are systemic heparins or regional citrate. To better understand use of anticoagulants for CRRT in the US, we surveyed nephrologists and critical care medicine (CCM) specialists.

METHODS

The survey contained 30 questions. Respondents were board certified and worked in intensive care units of academic medical centers or community hospitals.

RESULTS

150 physicians (70 nephrologists and 80 CCM) completed the survey. Mean number of CRRT machines in use increased ∼30% from the pre-pandemic era to 2022. Unfractionated heparin was the most used anticoagulant (43% of estimated patients) followed by citrate (28%). Respondents reported 29% of patients received no anticoagulant. Risk of hypocalcemia (52%) and citrate safety (42%) were the predominant reasons given for using no anticoagulant instead of citrate in heparin-intolerant patients. 84% said filter clogging was a problem when no anticoagulant was used, and almost 25% said increased transfusions were necessary. Respondents using heparin (n = 131) considered it inexpensive and easily obtainable, although of moderate safety, citing concerns of heparin-induced thrombocytopenia and bleeding. Anticoagulant citrate dextrose solution was the most used citrate. Respondents estimated that 37% of patients receiving citrate develop hypocalcemia and 17% citrate lock.

CONCLUSIONS

Given the increased use of CRRT and the lack of approved, safe, and effective anticoagulant choices for CRRT in the US, effective use of current and other anticoagulant options needs to be evaluated.

Local Inflammation But Not Kidney Cell Infection Associated with High APOL1 Expression in COVID-Associated Nephropathy

In coronavirus disease-19 biopsies, detection of severe acute respiratory syndrome coronavirus 2 was rare with no evidence of viral replication, whereas autopsy tissue failed quality control. In patients with FSGS, apolipoprotein L1 expression differed by degree of immune cell infiltrates, with some podocytes exhibiting up to 18-fold higher expression. In COVAN, the predicted high induction of apolipoprotein L1 expression occurs in a pattern consistent with the stochastic nature of FSGS pathology.

SARS-CoV-2 Infection and Death Rates Among Maintenance Dialysis Patients During Delta and Early Omicron Waves - United States, June 30, 2021-September 27, 2022

Persons receiving maintenance dialysis are at increased risk for SARS-CoV-2 infection and its severe outcomes, including death. However, rates of SARS-CoV-2 infection and COVID-19-related deaths in this population are not well described. Since November 2020, CDC's National Healthcare Safety Network (NHSN) has collected weekly data monitoring incidence of SARS-CoV-2 infections (defined as a positive SARS-CoV-2 test result) and COVID-19-related deaths (defined as the death of a patient who had not fully recovered from a SARS-CoV-2 infection) among maintenance dialysis patients. This analysis used NHSN dialysis facility COVID-19 data reported during June 30, 2021-September 27, 2022, to describe rates of SARS-CoV-2 infection and COVID-19-related death among maintenance dialysis patients. The overall infection rate was 30.47 per 10,000 patient-weeks (39.64 among unvaccinated patients and 27.24 among patients who had completed a primary COVID-19 vaccination series). The overall death rate was 1.74 per 10,000 patient-weeks. Implementing recommended infection control measures in dialysis facilities and ensuring patients and staff members are up to date with recommended COVID-19 vaccination is critical to limiting COVID-19-associated morbidity and mortality.