Diagnosis and Management of Immune Checkpoint Inhibitor-Associated Nephrotoxicity: A Position Statement from the American Society of Onco-nephrology.

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of cancer and are now the backbone of therapy for several malignancies. However, ICIs can cause a spectrum of renal immune-related adverse events including acute kidney injury (AKI), most commonly manifesting as acute interstitial nephritis (AIN), though glomerular disease and electrolyte disturbances have also been reported. In this position statement by the American Society of Onco-nephrology (ASON), we summarize the incidence and risk factors for ICI-AKI, pathophysiological mechanisms and clinicopathological features of ICI-AKI. We also discuss novel diagnostic approaches and promising biomarkers for ICI-AKI. From expert panel consensus, we provide clinical practice points for the initial assessment and diagnosis of ICI-AKI, management and immunosuppressive therapy, and consideration for re-challenge with ICI following AKI episodes. In addition, we explore ICI use in special populations such as kidney transplant recipients and propose key areas of focus for future research and clinical investigation.

IgA nephropathy relapse following COVID-19 vaccination treated with corticosteroid therapy: case report.

BACKGROUND: The flare of immune-mediated disease following coronavirus disease of 2019 (COVID-19) vaccination is a rare adverse event following immunization. De novo, as well as relapsing IgA nephropathy (IgAN) cases, have been reported following either mRNA-1273 (Moderna) or BNT162b2 (Pfizer-BioNTech) vaccination. To our knowledge, the majority of IgAN relapses did not result in severe acute kidney injury (AKI) and resolved spontaneously. CASE PRESENTATION: This is a case of a 54-year-old female with a previous diagnosis of IgAN who developed IgAN relapse following the second dose of Moderna vaccine. Gross hematuria developed 2 days after vaccination, which was accompanied by significant AKI. Kidney biopsy showed mild tubular atrophy and IgA staining in mesangium without crescent formation. Significant improvement in serum creatinine (Cr) was observed on day 10 after initiating prednisone. Cr came back to normal within 3 months after initiating corticosteroid. CONCLUSION: COVID-19 vaccination is associated with a flare of IgAN that may cause significant AKI. Steroid therapy is associated with recovery. IgAN flare after COVID-19 vaccination should be closely monitored to elucidate any adverse effect associated with the novel vaccine.

Thrombosis, Bleeding, and the Observational Effect of Early Therapeutic Anticoagulation on Survival in Critically Ill Patients With COVID-19.

BACKGROUND: Hypercoagulability may be a key mechanism of death in patients with coronavirus disease 2019 (COVID-19). OBJECTIVE: To evaluate the incidence of venous thromboembolism (VTE) and major bleeding in critically ill patients with COVID-19 and examine the observational effect of early therapeutic anticoagulation on survival. DESIGN: In a multicenter cohort study of 3239 critically ill adults with COVID-19, the incidence of VTE and major bleeding within 14 days after intensive care unit (ICU) admission was evaluated. A target trial emulation in which patients were categorized according to receipt or no receipt of therapeutic anticoagulation in the first 2 days of ICU admission was done to examine the observational effect of early therapeutic anticoagulation on survival. A Cox model with inverse probability weighting to adjust for confounding was used. SETTING: 67 hospitals in the United States. PARTICIPANTS: Adults with COVID-19 admitted to a participating ICU. MEASUREMENTS: Time to death, censored at hospital discharge, or date of last follow-up. RESULTS: Among the 3239 patients included, the median age was 61 years (interquartile range, 53 to 71 years), and 2088 (64.5%) were men. A total of 204 patients (6.3%) developed VTE, and 90 patients (2.8%) developed a major bleeding event. Independent predictors of VTE were male sex and higher D-dimer level on ICU admission. Among the 2809 patients included in the target trial emulation, 384 (11.9%) received early therapeutic anticoagulation. In the primary analysis, during a median follow-up of 27 days, patients who received early therapeutic anticoagulation had a similar risk for death as those who did not (hazard ratio, 1.12 [95% CI, 0.92 to 1.35]). LIMITATION: Observational design. CONCLUSION: Among critically ill adults with COVID-19, early therapeutic anticoagulation did not affect survival in the target trial emulation. PRIMARY FUNDING SOURCE: None.

AKI Treated with Renal Replacement Therapy in Critically Ill Patients with COVID-19.

BACKGROUND: AKI is a common sequela of coronavirus disease 2019 (COVID-19). However, few studies have focused on AKI treated with RRT (AKI-RRT). METHODS: We conducted a multicenter cohort study of 3099 critically ill adults with COVID-19 admitted to intensive care units (ICUs) at 67 hospitals across the United States. We used multivariable logistic regression to identify patient-and hospital-level risk factors for AKI-RRT and to examine risk factors for 28-day mortality among such patients. RESULTS: A total of 637 of 3099 patients (20.6%) developed AKI-RRT within 14 days of ICU admission, 350 of whom (54.9%) died within 28 days of ICU admission. Patient-level risk factors for AKI-RRT included CKD, men, non-White race, hypertension, diabetes mellitus, higher body mass index, higher d-dimer, and greater severity of hypoxemia on ICU admission. Predictors of 28-day mortality in patients with AKI-RRT were older age, severe oliguria, and admission to a hospital with fewer ICU beds or one with greater regional density of COVID-19. At the end of a median follow-up of 17 days (range, 1-123 days), 403 of the 637 patients (63.3%) with AKI-RRT had died, 216 (33.9%) were discharged, and 18 (2.8%) remained hospitalized. Of the 216 patients discharged, 73 (33.8%) remained RRT dependent at discharge, and 39 (18.1%) remained RRT dependent 60 days after ICU admission. CONCLUSIONS: AKI-RRT is common among critically ill patients with COVID-19 and is associated with a hospital mortality rate of >60%. Among those who survive to discharge, one in three still depends on RRT at discharge, and one in six remains RRT dependent 60 days after ICU admission.

Characteristics and Outcomes of Individuals With Pre-existing Kidney Disease and COVID-19 Admitted to Intensive Care Units in the United States.

RATIONALE & OBJECTIVE: Underlying kidney disease is an emerging risk factor for more severe coronavirus disease 2019 (COVID-19) illness. We examined the clinical courses of critically ill COVID-19 patients with and without pre-existing chronic kidney disease (CKD) and investigated the association between the degree of underlying kidney disease and in-hospital outcomes. STUDY DESIGN: Retrospective cohort study. SETTINGS & PARTICIPANTS: 4,264 critically ill patients with COVID-19 (143 patients with pre-existing kidney failure receiving maintenance dialysis; 521 patients with pre-existing non-dialysis-dependent CKD; and 3,600 patients without pre-existing CKD) admitted to intensive care units (ICUs) at 68 hospitals across the United States. PREDICTOR(S): Presence (vs absence) of pre-existing kidney disease. OUTCOME(S): In-hospital mortality (primary); respiratory failure, shock, ventricular arrhythmia/cardiac arrest, thromboembolic events, major bleeds, and acute liver injury (secondary). ANALYTICAL APPROACH: We used standardized differences to compare patient characteristics (values>0.10 indicate a meaningful difference between groups) and multivariable-adjusted Fine and Gray survival models to examine outcome associations. RESULTS: Dialysis patients had a shorter time from symptom onset to ICU admission compared to other groups (median of 4 [IQR, 2-9] days for maintenance dialysis patients; 7 [IQR, 3-10] days for non-dialysis-dependent CKD patients; and 7 [IQR, 4-10] days for patients without pre-existing CKD). More dialysis patients (25%) reported altered mental status than those with non-dialysis-dependent CKD (20%; standardized difference=0.12) and those without pre-existing CKD (12%; standardized difference=0.36). Half of dialysis and non-dialysis-dependent CKD patients died within 28 days of ICU admission versus 35% of patients without pre-existing CKD. Compared to patients without pre-existing CKD, dialysis patients had higher risk for 28-day in-hospital death (adjusted HR, 1.41 [95% CI, 1.09-1.81]), while patients with non-dialysis-dependent CKD had an intermediate risk (adjusted HR, 1.25 [95% CI, 1.08-1.44]). LIMITATIONS: Potential residual confounding. CONCLUSIONS: Findings highlight the high mortality of individuals with underlying kidney disease and severe COVID-19, underscoring the importance of identifying safe and effective COVID-19 therapies in this vulnerable population.

Serum electrolyte dynamics in multiple myeloma patients undergoing autologous haematopoietic stem cell transplantation.

AIM: High-dose melphalan followed by autologous haematopoietic cell transplantation remains the standard-of-care therapy for multiple myeloma (MM). Gastrointestinal toxicity concomitant with electrolyte derangement is a primary cause of morbidity from transplant. Here, we assessed the dynamics of electrolyte imbalances and its role in hematologic counts and engraftment. Ω Patients and Methods One hundred and eighteen MM patients that received transplant were studied. RESULTS: Engraftment speed (ES) was calculated as the period between the first rise in the absolute neutrophil count (ANC) and full engraftment defined as the first of three consecutive days with ANC > 500 × 106 /L. The defined median ES was 2 days (range 0-5 days) and 40 patients had ES ≤2 days. Engraftment occurred at a median of 10 days. The median time-to-nadir for phosphorus and potassium was 10 and 4.28 days, respectively. The drop in phosphorus and potassium serum level was statistically greater in patients with an ES ≤2 days compared to patients with ES ≥2 days. Magnesium level were not significantly affected and there was no significant difference between the drop in serum phosphorus and potassium based on severity of nausea or oral mucositis. CONCLUSION: Our results indicate that there is a significant correlation between the magnitude of drop in potassium and phosphorous levels and a steep rise in neutrophil counts around the engraftment period following stem cell transplant. These events indicate a "genesis syndrome" characterized by a rapid, massive transfer of electrolytes into proliferating cells as has been previously described after HCT for certain high-grade lymphomas and leukemias.

Tailorable optical scattering properties of V-shaped plasmonic nanoantennas: a computationally efficient and fast analysis.

In this work, we introduce an efficient computational scheme, based on the macro basis function method, to analyze the scattering of a plane wave by V-shaped plasmonic optical nanoantennas. The polarization currents and scattered fields for the both symmetric and antisymmetric excitations are investigated. We investigate how the resonant frequency of the plasmonic V-shaped nanoantenna is tailored by engineering the geometrical parameters and by changing the polarization state of the incident plane wave. The computational model presented herein is faster by many orders of magnitude than commercially available finite methods, and is capable of characterizing all nanoantennas comprised of junctions and bends of nanorods.

SGLT2 Inhibitors in Management of Severe Hypomagnesemia in Patients Without Diabetes: A Report of 4 Cases.

Sodium/glucose cotransporter 2 (SGLT2) inhibitors have demonstrated a class effect in improving serum magnesium levels in patients with diabetes. Additionally, recent reports have shown their promising beneficial effects in the treatment of refractory hypomagnesemia in patients with diabetes. However, their role in treating hypomagnesemia in patients without diabetes remains unexplored. Here, we report 4 cases of severe and refractory hypomagnesemia that showed dramatic improvement after initiating SGLT2 inhibitors in patients without diabetes. Case 1 had calcineurin inhibitor-associated severe hypomagnesemia. Cases 2, 3, and 4 had refractory hypomagnesemia associated with platinum-based chemotherapy with or without gastrointestinal losses. Case 1 was able to withdraw from high-dose oral magnesium supplementation. Cases 2 and 3 achieved independence from intravenous magnesium supplementation, whereas case 4 had decreased intravenous magnesium requirements. All the cases demonstrated sustainably improved serum magnesium levels. Withdrawal of SGLT2 inhibitors in case 4 resulted in worsening serum magnesium levels and intravenous magnesium requirements. The extraglycemic benefit of this group of medications not only suggests the need for further studies to better understand the effect of SGLT2 inhibitors on magnesium homeostasis but also supports expanded use in a larger patient population.

Immunoglobulin A nephropathy associated with mesothelioma.

Immunoglobulin A nephropathy (IgAN) has been identified in patients with various malignancies. Although membranous glomerulonephritis and minimal change disease have been described in patients with mesothelioma, to our knowledge IgAN associated with mesothelioma has not been reported. We present a case of IgAN, characterized by progressive deterioration of renal function from normal and confirmed by kidney biopsy. Despite improvement of renal function following treatment with cyclophosphamide and prednisone, the patient succumbed to acute respiratory failure 8 months later. We conclude that IgAN may be a potential complication of mesothelioma.

Immune Checkpoint Inhibitor-Associated AKI: Debates in Diagnosis, Management, and Rechallenge.

Immune checkpoint inhibitors (ICIs) are now established treatments for advanced cancer and their use is now ubiquitous. The high upside of ICIs is tempered by their toxicity profile affecting almost every organ, including the kidneys. Although acute interstitial nephritis is the major kidney-related adverse effect of checkpoint inhibitors, other manifestations such as electrolyte abnormalities and renal tubular acidosis have been described. With increasing awareness and recognition of these events, the focus has shifted to non-invasive identification of ICI-acute interstitial nephritis, with sophisticated approaches involving biomarkers and immunologic signatures being studied. Although the management of immune-related adverse events with corticosteroids is straightforward, there now are more data to help guide immunosuppressive regimens, ICI rechallenge, and delineate risk and efficacy in special populations such as individuals on dialysis or those who have received a transplant.

The Role of Kidney Biopsy in Immune Checkpoint Inhibitor-Associated AKI.

AKI in the setting of immune checkpoint inhibitors.Need for kidney biopsy for diagnosis of immune checkpoint inhibitors.Importance of pathology in diagnosis of immune checkpoint inhibitor-induced AKI.

Anemia Management in the Cancer Patient With CKD and End-Stage Kidney Disease.

Anemia is a common medical problem among patients with cancer and chronic kidney disease (CKD). Although anemia in patients with CKD is often treated with iron and erythropoietin-stimulating agents, there are controversies with regard to the use of erythropoietin-stimulating agents in cancer patients. In this article, we review the treatment of anemia in patients with cancer and CKD, in addition to summarizing the current guidelines in treatment of anemia in these patients.

Shorter versus longer corticosteroid duration and recurrent immune checkpoint inhibitor-associated AKI.

BACKGROUND: Corticosteroids are the mainstay of treatment for immune checkpoint inhibitor-associated acute kidney injury (ICPi-AKI), but the optimal duration of therapy has not been established. Prolonged use of corticosteroids can cause numerous adverse effects and may decrease progression-free survival among patients treated with ICPis. We sought to determine whether a shorter duration of corticosteroids was equally efficacious and safe as compared with a longer duration. METHODS: We used data from an international multicenter cohort study of patients diagnosed with ICPi-AKI from 29 centers across nine countries. We examined whether a shorter duration of corticosteroids (28 days or less) was associated with a higher rate of recurrent ICPi-AKI or death within 30 days following completion of corticosteroid treatment as compared with a longer duration (29-84 days). RESULTS: Of 165 patients treated with corticosteroids, 56 (34%) received a shorter duration of treatment and 109 (66%) received a longer duration. Patients in the shorter versus longer duration groups were similar with respect to baseline and ICPi-AKI characteristics. Five of 56 patients (8.9%) in the shorter duration group and 12 of 109 (11%) in the longer duration group developed recurrent ICPi-AKI or died (p=0.90). Nadir serum creatinine in the first 14, 28, and 90 days following completion of corticosteroid treatment was similar between groups (p=0.40, p=0.56, and p=0.89, respectively). CONCLUSION: A shorter duration of corticosteroids (28 days or less) may be safe for patients with ICPi-AKI. However, the findings may be susceptible to unmeasured confounding and further research from randomized clinical trials is needed.

Serum amyloid A-type amyloidosis of the kidney and immune complex-mediated glomerulopathy in the setting of hyperimmunoglobulin E (Job's) syndrome.

Hyperimmunoglobulin E syndrome (HIES) is a rare immunodeficiency syndrome with characteristic features of pulmonary infections, eczema, recurrent skin abscesses and elevated serum IgE. We present a case of an HIES patient referred for nephrology consultation with elevated serum creatinine and nephrotic-range proteinuria. The subsequent kidney biopsy revealed AA-type amyloidosis and a separate and distinct inactive immune complex-mediated glomerulopathy with frequent glomerular capillary wall and mesangial polyclonal deposits. Potential kidney pathology in the setting of HIES has not been well described previously, and this case provides insight into associated renal comorbidities faced by patients with this rare syndrome.

Incidence of symptomatic venous thromboembolism following hospitalization for coronavirus disease 2019: Prospective results from a multi-center study.

BACKGROUND: Thrombosis and pulmonary embolism appear to be major causes of mortality in hospitalized coronavirus disease 2019 (COVID-19) patients. However, few studies have focused on the incidence of venous thromboembolism (VTE) after hospitalization for COVID-19. METHODS: In this multi-center study, we followed 1529 COVID-19 patients for at least 45 days after hospital discharge, who underwent routine telephone follow-up. In case of signs or symptoms of pulmonary embolism (PE) or deep vein thrombosis (DVT), they were invited for an in-hospital visit with a pulmonologist. The primary outcome was symptomatic VTE within 45 days of hospital discharge. RESULTS: Of 1529 COVID-19 patients discharged from hospital, a total of 228 (14.9%) reported potential signs or symptoms of PE or DVT and were seen for an in-hospital visit. Of these, 13 and 12 received Doppler ultrasounds or pulmonary CT angiography, respectively, of whom only one patient was diagnosed with symptomatic PE. Of 51 (3.3%) patients who died after discharge, two deaths were attributed to VTE corresponding to a 45-day cumulative rate of symptomatic VTE of 0.2% (95%CI 0.1%-0.6%; n = 3). There was no evidence of acute respiratory distress syndrome (ARDS) in these patients. Other deaths after hospital discharge included myocardial infarction (n = 13), heart failure (n = 9), and stroke (n = 9). CONCLUSIONS: We did not observe a high rate of symptomatic VTE in COVID-19 patients after hospital discharge. Routine extended thromboprophylaxis after hospitalization for COVID-19 may not have a net clinical benefit. Randomized trials may be warranted.

Acute kidney injury in patients treated with immune checkpoint inhibitors.

BACKGROUND: Immune checkpoint inhibitor-associated acute kidney injury (ICPi-AKI) has emerged as an important toxicity among patients with cancer. METHODS: We collected data on 429 patients with ICPi-AKI and 429 control patients who received ICPis contemporaneously but who did not develop ICPi-AKI from 30 sites in 10 countries. Multivariable logistic regression was used to identify predictors of ICPi-AKI and its recovery. A multivariable Cox model was used to estimate the effect of ICPi rechallenge versus no rechallenge on survival following ICPi-AKI. RESULTS: ICPi-AKI occurred at a median of 16 weeks (IQR 8-32) following ICPi initiation. Lower baseline estimated glomerular filtration rate, proton pump inhibitor (PPI) use, and extrarenal immune-related adverse events (irAEs) were each associated with a higher risk of ICPi-AKI. Acute tubulointerstitial nephritis was the most common lesion on kidney biopsy (125/151 biopsied patients [82.7%]). Renal recovery occurred in 276 patients (64.3%) at a median of 7 weeks (IQR 3-10) following ICPi-AKI. Treatment with corticosteroids within 14 days following ICPi-AKI diagnosis was associated with higher odds of renal recovery (adjusted OR 2.64; 95% CI 1.58 to 4.41). Among patients treated with corticosteroids, early initiation of corticosteroids (within 3 days of ICPi-AKI) was associated with a higher odds of renal recovery compared with later initiation (more than 3 days following ICPi-AKI) (adjusted OR 2.09; 95% CI 1.16 to 3.79). Of 121 patients rechallenged, 20 (16.5%) developed recurrent ICPi-AKI. There was no difference in survival among patients rechallenged versus those not rechallenged following ICPi-AKI. CONCLUSIONS: Patients who developed ICPi-AKI were more likely to have impaired renal function at baseline, use a PPI, and have extrarenal irAEs. Two-thirds of patients had renal recovery following ICPi-AKI. Treatment with corticosteroids was associated with improved renal recovery.