COVID-19 and kidneys: A follow-up.

In coronavirus disease 2019 (COVID-19) patients, acute tubular injury is the most frequently documented kidney disease. According to the current knowledge, its cause is assumed to be multifactorial. Other kidney diseases observed in non-severely ill COVID-19 patients are thrombotic microangiopathy, necrotizing glomerulonephritis, primary podocytopathy and interstitial nephritis. Even after a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, necrotizing glomerulonephritis and other kidney diseases were observed. It is recommended that a renal biopsy be performed in COVID-19 patients with elevated creatinine, proteinuria, and/or hematuria to rule out a variety of other renal disorders. Both diseases (during a SARS-CoV-2 infection and after vaccination) probably share common features that act as triggers when the patient is preconditioned for a renal disease. The activation of the complement system and the formation of neutrophil extracellular traps (NET) could play a role in the pathogenesis. As the first report on autopsies carried out on COVID-19 patients throughout Germany showed, the autopsy plays a central role for a better understanding of this (relatively) new disease.Copyright © 2022, The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.

Renal Biopsy Diagnosis of Acute Tubular Injury after Pfizer-BioNTech COVID-19 Vaccination: A Case Report.

Coronavirus disease 2019 (COVID-19) is a severe respiratory infection that can be fatal in unvaccinated individuals; however, acute kidney injury (AKI) is a rare adverse reaction to COVID-19 vaccination. AKI resulting from multiple conditions can have severe consequences, including end-stage renal failure, if not treated with immunosuppressive agents. However, acute tubular injury (ATI) as the sole cause of AKI has not been previously reported. Herein, we discuss an obese 54-year-old man with type 2 diabetes who received four COVID-19 vaccines; three from Pfizer and one from Moderna. Diabetic retinopathy, urinary protein, and occult blood were absent with no other underlying diseases. There was no history of COVID-19 infection. He was referred to our hospital 5 days after receiving the fourth Pfizer-BioNTech COVID-19 vaccine dose with stage 3 AKI. Urinary findings revealed new proteinuria and glomerular occult blood. Physical examination and infection testing were unremarkable. Steroids were introduced on admission for rapidly progressive glomerulonephritis. A renal biopsy performed on Day 2 revealed only ATI. Therefore, steroids were discontinued on Day 5, after which renal function recovered spontaneously, and urinalysis abnormalities disappeared. Renal function remained normal during follow-up. We report a case of AKI with severe renal dysfunction after COVID-19 vaccination, wherein renal biopsy effectively determined the disease status (ATI), which did not require immunosuppressive treatment.

Pathological findings in COVID-19: A conventional autopsy-based study from India.

Background & objectives: Autopsy study has been considered the gold standard method for studying the effects of any disease on the body. Since COVID-19 is a novel disease, autopsy is crucial to understand its pathophysiology. This study was conducted to analyze the microscopic and macroscopic findings of various organs in COVID-19 and to associate those findings with clinical observations and laboratory findings. Methods: Conventional invasive autopsies were performed on 33 patients with COVID-19 from September 7, 2020 to December 23, 2020. All the organs were removed by routine dissection techniques and preserved in 10 per cent formalin. The tissues were processed and stained according to standard practices using haematoxylin-eosin (H & E) and periodic acid-schiff (PAS) stain. Results: The study included 28 males and 5 females with a median age of 61 yr (range 30-90 yr). Massive pulmonary oedema and thrombi in the lungs were the characteristic features macroscopically. On microscopic examination, diffuse alveolar damage in the exudative/proliferative phase was found in 29 (87.88%) cases. Among the other notable microscopic findings were bronchopneumonia and lung abscesses due to secondary bacterial infection (n=17, 51.52%), acute tubular injury (n=21, 63.64%) and thrombi in the lungs, heart, and kidneys. Interpretation & conclusions: COVID-19 primarily affected the respiratory and the renal systems in the vast majority of severely affected patients in our study. We also found signs of hypercoagulability, as evidenced by widespread thrombi in multiple organs, along with a raised d-dimer level and a hyperinflammatory state manifested by elevated inflammatory markers. Our autopsy findings and altered laboratory investigations support the role of immune-mediated cellular injury along with direct virus-mediated cellular damage.

COVID-19 und Niere

In coronavirus disease 2019 (COVID-19) patients, acute tubular injury is the most frequently documented kidney disease. According to the current knowledge, its cause is assumed to be multifactorial. Other kidney diseases observed in non-severely ill COVID-19 patients are thrombotic microangiopathy, necrotizing glomerulonephritis, primary podocytopathy and interstitial nephritis. Even after a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, necrotizing glomerulonephritis and other kidney diseases were observed. It is recommended that a renal biopsy be performed in COVID-19 patients with elevated creatinine, proteinuria, and/or hematuria to rule out a variety of other renal disorders. Both diseases (during a SARS-CoV-2 infection and after vaccination) probably share common features that act as triggers when the patient is preconditioned for a renal disease. The activation of the complement system and the formation of neutrophil extracellular traps (NET) could play a role in the pathogenesis. As the first report on autopsies carried out on COVID-19 patients throughout Germany showed, the autopsy plays a central role for a better understanding of this (relatively) new disease.

Elevated Neutrophil Gelatinase-Associated Lipocalin Is Associated With the Severity of Kidney Injury and Poor Prognosis of Patients With COVID-19.

INTRODUCTION: Loss of kidney function is a common feature of COVID-19 infection, but serum creatinine (SCr) is not a sensitive or specific marker of kidney injury. We tested whether molecular biomarkers of tubular injury measured at hospital admission were associated with acute kidney injury (AKI) in those with COVID-19 infection. METHODS: This is a prospective cohort observational study consisting of 444 consecutive patients with SARS-CoV-2 enrolled in the Columbia University emergency department (ED) at the peak of the pandemic in New York (March 2020-April 2020). Urine and blood were collected simultaneously at hospital admission (median time: day 0, interquartile range: 0-2 days), and urine biomarkers were analyzed by enzyme-linked immunosorbent assay (ELISA) and a novel dipstick. Kidney biopsies were probed for biomarker RNA and for histopathologic acute tubular injury (ATI) scores. RESULTS: Admission urinary neutrophil gelatinase-associated lipocalin (uNGAL) level was associated with AKI diagnosis (267 ± 301 vs. 96 ± 139 ng/ml, P < 0.0001) and staging; uNGAL levels >150 ng/ml had 80% specificity and 75% sensitivity to diagnose AKI stages 2 to 3. Admission uNGAL level quantitatively associated with prolonged AKI, dialysis, shock, prolonged hospitalization, and in-hospital death, even when admission SCr level was not elevated. The risk of dialysis increased almost 4-fold per SD of uNGAL independently of baseline SCr, comorbidities, and proteinuria (odds ratio [OR] [95% CI]: 3.59 [1.83-7.45], P < 0.001). In the kidneys of those with COVID-19, NGAL mRNA expression broadened in parallel with severe histopathologic injury (ATI). Conversely, low uNGAL levels at admission ruled out stages 2 to 3 AKI (negative predictive value: 0.95, 95% CI: 0.92-0.97) and the need for dialysis (negative predictive value: 0.98, 95% CI: 0.96-0.99). Although proteinuria and urinary (u)KIM-1 were implicated in tubular injury, neither was diagnostic of AKI stages. CONCLUSION: In the patients with COVID-19, uNGAL level was quantitatively associated with histopathologic injury (ATI), loss of kidney function (AKI), and severity of patient outcomes.

COVID-19-induced acute renal tubular injury associated with elevation of serum inflammatory cytokine.

BACKGROUND: Severe acute respiratory syndrome Coronavirus 2 has rapidly spread worldwide, with acute kidney injury (AKI) as one of the manifestations with unknown causal mechanisms. We aimed to investigate tubular injury by assessing tubular markers and their association with the severity of Coronavirus disease 2019 (COVID-19). METHODS: We examined the associations between laboratory markers and urinary levels of N-acetyl-ß-D-glucosaminidase (uNAG), ß2-microglobulin (u ß2MG), α1-microglobulin (u α1MG), and liver-type fatty acid binding protein (L-FABP). We studied 18 COVID-19 patients without previous chronic kidney disease and analyzed the relationship between the urinary biomarkers and inflammatory markers in patients with severe (n = 7) or non-severe (n = 11) COVID-19, defined by requirements of supplemental oxygen. RESULTS: Fourteen patients (78%) showed abnormal urinalysis findings and two (11%) developed AKI. Patients with severe COVID-19 had significantly higher levels of proteinuria, uNAG, uß2MG, uα 1MG, and L-FABP than those with non-severe disease. Serum levels of interleukin-6 (IL-6) were significantly higher on admission in all severe COVID-19 cases and correlated with the levels of L-FABP, uß2MG, uα1MG, uNAG, and proteinuria. Moreover, the changes in serum IL-6 (ΔIL-6) levels from baseline to 7 days after admission significantly correlated with ΔL-FABP and Δuß2MG. CONCLUSIONS: Levels of tubular injury markers, especially L-FABP and uß2MG, were significantly associated with IL-6 levels even in patients with no evident AKI. This suggests that L-FABP and uß2MG could be useful as early detective biomarkers for COVID-19 associated renal injury.

Minimal Change Disease With Severe Acute Kidney Injury Following the Oxford-AstraZeneca COVID-19 Vaccine: A Case Report.

We report a case of minimal change disease (MCD) with severe acute kidney injury (AKI) following the first injection of the ChAdOx1 nCoV-19 (AZD1222) vaccine from Oxford-AstraZeneca against coronavirus disease 2019 (COVID-19). A 71-year-old man with a history of dyslipidemia and a baseline serum creatinine of 0.7mg/dL presented with nephrotic syndrome, AKI, and severe hypertension 13 days after receiving the Oxford-AstraZeneca vaccine. Refractory hyperkalemia and hypervolemia with oligoanuria prompted initiation of hemodialysis. His serum albumin was 2.6g/dL and his urinary protein-creatinine ratio was 2,321mg/mmol. Given a high suspicion for rapidly progressive glomerulonephritis, empirical glucocorticoid treatment was initiated (3 methylprednisolone pulses followed by high-dose prednisone). A kidney biopsy showed MCD and acute tubular injury. Kidney function and proteinuria subsequently improved, and hemodialysis was discontinued 38 days after the start of therapy. This case describes de novo MCD after the Oxford-AstraZeneca vaccine. It adds to the few published case reports of MCD after the Pfizer-BioNTech COVID-19 vaccine. Further reports and studies will be needed to elucidate whether MCD is truly associated with COVID-19 vaccination.

Minimal Change Disease Following the Pfizer-BioNTech COVID-19 Vaccine.

We report on the development of minimal change disease (MCD) with nephrotic syndrome and acute kidney injury (AKI), shortly after first injection of the BNT162b2 COVID-19 vaccine (Pfizer-BioNTech). A 50-year-old previously healthy man was admitted to our hospital following the appearance of peripheral edema. Ten days earlier, he had received the first injection of the vaccine. Four days after injection, he developed lower leg edema, which rapidly progressed to anasarca. On admission, serum creatinine was 2.31 mg/dL and 24-hour urinary protein excretion was 6.9 grams. As kidney function continued to decline over the next days, empirical treatment was initiated with prednisone 80 mg/d. A kidney biopsy was performed and the findings were consistent with MCD. Ten days later, kidney function began to improve, gradually returning to normal. The clinical triad of MCD, nephrotic syndrome, and AKI has been previously described under a variety of circumstances, but not following the Pfizer-BioNTech COVID-19 vaccine. The association between the vaccination and MCD is at this time temporal and by exclusion, and by no means firmly established. We await further reports of similar cases to evaluate the true incidence of this possible vaccine side effect.

The spectrum of kidney biopsies in hospitalized patients with COVID-19, acute kidney injury, and/or proteinuria.

We report a multicentric retrospective case series of patients with COVID-19 who developed acute kidney injury and/or proteinuria and underwent a kidney biopsy in the Paris and its metropolitan area. Forty-seven patients (80.9% men) with COVID-19 who underwent a kidney biopsy between March 08 and May 19, 2020 were included. Median age was 63 years IQR [52-69]. Comorbidities included hypertension (66.0%), diabetes mellitus (27.7%), obesity (27.7%), history of chronic kidney (25.5%), cardiac (38.6%) and respiratory (27.3%) diseases. Initial symptoms were fever (85.1%), cough (63.8%), shortness of breath (55.3%), and diarrhea (23.4%). Almost all patients developed acute kidney injury (97.9%) and 63.8% required renal replacement therapy. Kidney biopsy showed two main histopathological patterns, including acute tubular injury in 20 (42.6%) patients, and glomerular injury consisting of collapsing glomerulopathy and focal segmental glomerulosclerosis in 17 (36.2%) patients. Two (4.3%) patients had acute vascular nephropathy, while eight (17%) had alternative diagnosis most likely unrelated to COVID-19. Acute tubular injury occurred almost invariably in the setting of severe forms of COVID-19, whereas patients with glomerular injury had various profiles of COVID-19 severity and collapsing glomerulopathy was only observed in patients harboring a combination of APOL1 risk variants. At last follow-up, 16 of the 30 patients who initially required dialysis were still on dialysis, and 9 died. The present study describes the spectrum of kidney lesions in patients with COVID-19. While acute tubular injury is correlated with COVID-19 severity, the pattern of glomerular injury is intimately associated with the expression of APOL1 risk variants.

[COVID-19 and kidney involvement]. / COVID-19 und Nierenbefall: Pathologie.

Apart from the pulmonary disease, acute kidney injury is one of the most frequent and most severe organ complications in severe coronavirus disease 2019 (COVID-19). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could also be detected in renal tissue. Patients with chronic kidney disease and on dialysis as well as kidney transplantation patients represent a particularly vulnerable population. The increasing number of patients infected with SARS-CoV­2 has aroused increased interest in the exact pathophysiology and morphology of kidney damage as well as the direct detection of the virus in the kidneys, which in contrast to the lungs is overall more difficult to perform. Meanwhile, data from several large autopsy and kidney biopsy studies are now available. While the detection of SARS-CoV­2 RNA in tissue leads to consistently reproducible results, the use of electron microscopy for visualization of the virus is critically discussed due to various artefacts. The exact and direct effects of SARS-CoV­2 on the kidneys are not yet known in detail and are currently the focus of intensive research.

Zebra-like bodies in COVID-19: is phospholipidosis evidence of hydroxychloroquine induced acute kidney injury?

COVID-19 (from SARS-CoV-2) is the cause of an ongoing pandemic, with an increasing number of cases and significant mortality worldwide. Clinical trials and extensive studies are being conducted on a large scale for a better understanding of the pathophysiology of this disease and its effect on different organs. Several experimental treatment protocols have been introduced, in which hydroxychloroquine (HCQ) was one of the first drugs used. While patients can develop many side effects of HCQ, studies have documented a rare association of long-term HCQ treatment with zebra-like bodies in the ultrastructural examination of kidney biopsies, a finding typically seen in Fabry's disease, as well as in association with chronic HCQ use, among other drugs. We present a similar finding in the postmortem examination of a male in his early seventies with COVID-19 infection, who received five days of HCQ treatment before stopping the medication due to cardiac and renal toxicity.

Postmortem Kidney Pathology Findings in Patients with COVID-19.

BACKGROUND: AKI is common among hospitalized patients with coronavirus disease 2019 (COVID-19) and is an independent risk factor for mortality. Although there are numerous potential mechanisms underlying COVID-19-associated AKI, our current knowledge of kidney pathologic findings in COVID-19 is limited. METHODS: We examined the postmortem kidneys from 42 patients who died of COVID-19. We reviewed light microscopy findings in all autopsies and performed immunofluorescence, electron microscopy, and in situ hybridization studies for SARS-CoV-2 on a subset of samples. RESULTS: The cohort had a median age of 71.5 years (range, 38-97 years); 69% were men, 57% were Hispanic, and 73% had a history of hypertension. Among patients with available data, AKI developed in 31 of 33 patients (94%), including 6 with AKI stage 1, 9 with stage 2, and 16 with stage 3. The predominant finding correlating with AKI was acute tubular injury. However, the degree of acute tubular injury was often less severe than predicted for the degree of AKI, suggesting a role for hemodynamic factors, such as aggressive fluid management. Background changes of hypertensive arterionephrosclerosis and diabetic glomerulosclerosis were frequent but typically mild. We identified focal kidney fibrin thrombi in 6 of 42 (14%) autopsies. A single Black patient had collapsing FSGS. Immunofluorescence and electron microscopy were largely unrevealing, and in situ hybridization for SARS-CoV-2 showed no definitive positivity. CONCLUSIONS: Among a cohort of 42 patients dying with COVID-19, autopsy histologic evaluation revealed acute tubular injury, which was typically mild relative to the degree of creatinine elevation. These findings suggest potential for reversibility upon resolution of SARS-CoV-2 infection.

Characterization of acute kidney injury in critically ill patients with severe coronavirus disease 2019.

BACKGROUND: Coronavirus disease 2019 (COVID-19)-associated acute kidney injury (AKI) frequency, severity and characterization in critically ill patients has not been reported. METHODS: Single-centre cohort performed from 3 March 2020 to 14 April 2020 in four intensive care units in Bordeaux University Hospital, France. All patients with COVID-19 and pulmonary severity criteria were included. AKI was defined using Kidney Disease: Improving Global Outcomes (KDIGO) criteria. A systematic urinary analysis was performed. The incidence, severity, clinical presentation, biological characterization (transient versus persistent AKI; proteinuria, haematuria and glycosuria) and short-term outcomes were evaluated. RESULTS: Seventy-one patients were included, with basal serum creatinine (SCr) of 69 ± 21 µmol/L. At admission, AKI was present in 8/71 (11%) patients. Median [interquartile range (IQR)] follow-up was 17 (12-23) days. AKI developed in a total of 57/71 (80%) patients, with 35% Stage 1, 35% Stage 2 and 30% Stage 3 AKI; 10/57 (18%) required renal replacement therapy (RRT). Transient AKI was present in only 4/55 (7%) patients and persistent AKI was observed in 51/55 (93%). Patients with persistent AKI developed a median (IQR) urine protein/creatinine of 82 (54-140) (mg/mmol) with an albuminuria/proteinuria ratio of 0.23 ± 20, indicating predominant tubulointerstitial injury. Only two (4%) patients had glycosuria. At Day 7 after onset of AKI, six (11%) patients remained dependent on RRT, nine (16%) had SCr >200 µmol/L and four (7%) had died. Day 7 and Day 14 renal recovery occurred in 28% and 52%, respectively. CONCLUSION: Severe COVID-19-associated AKI is frequent, persistent, severe and characterized by an almost exclusive tubulointerstitial injury without glycosuria.