OUP accepted manuscript

Treatment of acute kidney injury with continuous renal replacement therapy and cytokine adsorber (CytoSorb®) in critically ill patients with COVID-19

INTRODUCTION

This retrospective study aimed to evaluate the 30 and 60-day survival of critically ill patients with COVID-19 and AKI.

METHODS

Inflammatory and biochemical biomarkers, length of intensive care unit (ICU) stay and mortality at Day 30 and Day 60 after ICU admission were analyzed. A total of 44 patients treated with continuous renal replacement therapy (CRRT) with cytokine adsorber (CA group) were compared to 58 patients treated with CRRT alone (non-CA group).

RESULTS

Patients in CA group were younger, had better preserved kidney function prior to the beginning of CRRT and had higher levels of interleukin-6. There were no statistically significant differences in their comorbidities and in other measured biomarkers between the two groups. The number of patients who died 60 days after ICU admission was statistically significantly higher in non-CA group (p = 0.029).

CONCLUSION

Treatment with CRRT and cytokine adsorber may have positively influenced 60-day survival in our COVID-19 ICU patients with AKI.

A case of biopsy-proven acute interstitial nephritis following atezolizumab-bevacizumab treatment of advanced unresectable hepatocellular carcinoma

BACKGROUND

The advent of immune checkpoint inhibitors (ICIs) represented a significant breakthrough in cancer therapy. Recently, the combined use of atezolizumab and bevacizumab was approved as first-line treatment for unresectable hepatocellular carcinoma (HCC). Exposure to a novel and diverse spectrum of immune-related adverse events (irAEs) has increased with the growing utilization of ICIs, however, a comprehensive understanding surrounding newer agents is still lacking. The incidence of kidney toxicities is rare but rising, often underreported due to the lack of confirmatory biopsies. Here, we present a rare case of biopsy-proven acute interstitial nephritis (AIN) following atezolizumab-bevacizumab treatment of advanced unresectable HCC.

CASE

An 84-year-old male with T4N0M0 hepatocellular carcinoma was admitted after cycle 5 of atezolizumab due to decreased urine output and dysuria with a serum creatine of 4.7 mg/dL compared to a baseline of 1.3 mg/dL. To confirm the diagnosis of possible intrinsic renal injury, an ultrasound-guided non-focal biopsy of the left kidney was performed, revealing AIN. Potential exacerbatory medications, such as proton-pump inhibitors, were discontinued. The patient was discharged on oral steroids with improvement in serum creatinine. Before completing the steroid taper, the patient developed pneumocystis pneumonia and eventually transitioned to hospice care.

CONCLUSION

This case highlights the valuable role renal biopsy can play in accurately capturing irAEs and guiding appropriate management in the setting of ICI-induced AKI. It also exemplifies important considerations for steroid treatment of irAEs in the setting of comorbidities, such as diabetes.

Tubulointerstitial Nephritis and Uveitis Syndrome During the COVID-19 Pandemic: A Case Series

Objectives

To report the ocular findings, laboratory results, and management of patients with tubulointerstitial nephritis and uveitis syndrome (TINU), whose numbers increased during the 2019 coronavirus disease (COVID-19) pandemic.

Materials and Methods

Demographic characteristics, ophthalmic examination findings, laboratory results including polymerase chain reaction (PCR) test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), serum SARS-CoV-2 immunoglobulin G (IgG) antibody, and treatment of patients diagnosed with TINU between March 2020 and March 2022 were evaluated retrospectively.

Results

The study included 19 eyes of 10 patients (6 female/4 male). The mean age was 13.5±2.4 years (range: 8-16 years). The mean follow-up duration was 13.5±6.1 months (range: 6-24 months). All patients presented with anterior uveitis. Anterior uveitis was bilateral in 9 patients (90%) and unilateral in 1 patient (10%). Posterior segment findings were normal in 8 patients (80%), and bilateral optic disc edema was observed in only 2 patients (20%). None of the patients had a previous SARS-CoV-2 infection and/or vaccination history. The SARS-CoV-2 PCR test was negative in all patients at presentation. The SARS-CoV-2 IgG antibody test was reactive in 7 patients (70%). Recurrent uveitis developed in 8 patients (80%) during follow-up. Systemic immunomodulatory therapy was required for the control of ocular inflammation in 7 patients (70%) with severe uveitis flare-ups.

Conclusion

TINU is a multisystemic autoimmune disease, especially in response to environmental triggering factors such as viral infections. Although TINU is a rare disease, the number of cases increased during the COVID-19 pandemic. SARS-CoV-2 antibodies were detected at a significant rate of 70% in these patients, who did not have a history of SARS-CoV-2 infection and vaccination. Previous asymptomatic SARS-CoV-2 infection in children may be a triggering factor in the development of TINU.

New-Onset Acute Interstitial Nephritis Post-SARS-CoV-2 Infection and COVID-19 Vaccination: A Panoramic Review

The 2019 coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) has posed a considerable challenge to global healthcare. Acute interstitial nephritis (AIN) post SARS-CoV-2 infection and vaccination has been reported, but its clinical features and pathogenesis remained unclear. We reviewed so far the largest 22 cases of AIN post SARS-CoV-2 infection and 36 cases of AIN following COVID-19 vaccination. The onset of AIN was mainly related to messenger RNA vaccines (52.8%). Apart from fever, proteinuria (45.5%) was the main manifestation of AIN post SARS-CoV-2 infection, left acute kidney injury (AKI, 63.9%) in patients post COVID-19 vaccination. The potential mechanism of vaccination induced AIN was conjugating vaccines with proteins to form a hapten, which activated dendritic cells and promoted a cascade immunological reaction leading to AIN.

Tubulointerstitial nephritis and uveitis syndrome and SARS-CoV-2 infection in an adolescent: just a coincidence in time?

BACKGROUND

Despite recent well-established kidney tropism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), usually presenting as acute kidney injury (AKI), there are few published cases with SARS-CoV-2-related tubulointerstitial nephritis (TIN). We report an adolescent with TIN and delayed association with uveitis (TINU syndrome), where SARS-CoV-2 spike protein was identified in kidney biopsy.

CASE-DIAGNOSIS/TREATMENT

A 12-year-old girl was assessed for a mild elevation of serum creatinine detected during the evaluation of systemic manifestations including asthenia, anorexia, abdominal pain, vomiting, and weight loss. Data of incomplete proximal tubular dysfunction (hypophosphatemia and hypouricemia with inappropriate urinary losses, low molecular weight proteinuria, and glucosuria) were also associated. Symptoms had initiated after a febrile respiratory infection with no known infectious cause. After 8 weeks, the patient tested positive in PCR for SARS-CoV-2 (Omicron variant). A subsequent percutaneous kidney biopsy revealed TIN and immunofluorescence staining with confocal microscopy detected the presence of SARS-CoV-2 protein S within the kidney interstitium. Steroid therapy was started with gradual tapering. Ten months after onset of clinical manifestations, as serum creatinine remained slightly elevated and kidney ultrasound showed mild bilateral parenchymal cortical thinning, a second percutaneous kidney biopsy was performed, without demonstrating acute inflammation or chronic changes, but SARS-CoV-2 protein S within the kidney tissue was again detected. At that moment, simultaneous routine ophthalmological examination revealed an asymptomatic bilateral anterior uveitis.

CONCLUSIONS

We present a patient who was found to have SARS-CoV-2 in kidney tissue several weeks following onset of TINU syndrome. Although simultaneous infection by SARS-CoV-2 could not be demonstrated at onset of symptoms, since no other etiological cause was identified, we hypothesize that SARS-CoV-2 might have been involved in triggering the patient's illness.

Intrinsic Kidney Pathology in Children and Adolescents Following COVID-19 Vaccination: A Systematic Review

Global COVID-19 vaccination programs for children and adolescents have been developed with international clinical trial data confirming COVID-19 mRNA vaccine safety and efficacy for the pediatric population. The impact of COVID-19 vaccination in the kidneys is thought to be explained by a complex immune-mediated relationship between the two, although the pathophysiological mechanisms of how COVID-19 vaccination potentially induces kidney pathology are not presently well known. Whilst intrinsic kidney pathologies following COVID-19 vaccination have been reported in adults, such cases are only being recently reported with greater frequency in children and adolescents. Conforming to the PRISMA checklist, we conducted a systematic review of the current literature to provide an overview on the range of intrinsic kidney pathologies that have been reported following COVID-19 vaccination in children and adolescents. All English language research articles published on or before 30 June 2022 reporting new-onset or relapsed intrinsic kidney pathology in children or adolescents (≤18 years) following COVID-19 vaccination were selected for qualitative analysis. Out of 18 cases from the 13 published articles selected, there were 10 cases of IgA nephropathy (1 case of rapidly progressive glomerulonephritis requiring acute hemodialysis), 5 cases of minimal change disease (MCD), 1 case of concurrent MCD/tubulointerstitial nephritis (TIN) and 2 cases of TIN. There is no indication currently to avoid vaccination, unless specific circumstances exist, as the benefits of COVID-19 vaccination far outweigh its risks. Concluding the findings from our systematic review based on preliminary evidence, potential adverse effects to the kidney from COVID-19 vaccination affects a small number of children and adolescents among the many who have been vaccinated. There remains good reason at present to support vaccination of children and adolescents with a greater morbidity status, such as those living with preexisting chronic kidney disease. Close observation of all children and adolescents receiving COVID-19 vaccination is recommended, particularly in those with preceding intrinsic kidney pathology to identify risks of relapsed disease.