Kidney involvement in multisystem inflammatory syndrome in children: a pediatric nephrologist's perspective

Acute kidney injury in children with moderate-severe COVID-19 and multisystem inflammatory syndrome in children: a referral center experience

BACKGROUND

Data on the characteristics of acute kidney injury (AKI) in pediatric COVID-19 and MIS-C are limited. We aimed to define the frequency, associated factors and early outcome of AKI in moderate, severe or critical COVID-19 and MIS-C; and to present a tertiary referral center experience from Türkiye.

METHODS

Hospitalized patients ≤ 18 years of age with confirmed COVID-19 or MIS-C at İhsan Doğramacı Children's Hospital, Hacettepe University, between March 2020-December 2021 were enrolled. The characteristics of AKI in the COVID-19 group were investigated in moderate, severe and critically ill patients; patients with mild COVID-19 were excluded.

RESULTS

The median (Q1-Q3) age in the COVID-19 (n = 66) and MIS-C (n = 111) groups was 10.7 years (3.9-15.2) and 8.7 years (4.5-12.7), respectively. The frequency of AKI was 22.7% (15/66) in COVID-19 and 15.3% (17/111) in MIS-C; all MIS-C patients with AKI and 73.3% (11/15) of COVID-19 patients with AKI had AKI at the time of admission. Multivariate analyses revealed need for vasoactive/inotropic agents [Odds ratio (OR) 19.233, p = 0.002] and presence of vomiting and/or diarrhea (OR 4.465, p = 0.036) as independent risk factors of AKI in COVID-19 patients; and need for vasoactive/inotropic agents (OR 22.542, p = 0.020), procalcitonin and ferritin levels as independent risk factors of AKI in the MIS-C group. Age was correlated with lymphocyte count (r = -0.513, p < 0.001) and troponin level (r = 0.518, p < 0.001) in MIS-C patients. Length of hospital stay was significantly longer in both groups with AKI, compared to those without AKI. Mortality was 9.1% in the COVID-19 group; and was associated with AKI (p = 0.021). There was no mortality in MIS-C patients. AKI recovery at discharge was 63.6% in COVID-19 survivors and 100% in MIS-C patients.

CONCLUSIONS

Independent risk factors for AKI were need for vasoactive/inotropic agents and vomiting/diarrhea in moderate, severe or critical COVID-19 patients; and need for vasoactive/inotropic agents and severe inflammation in MIS-C patients. Our findings suggest that inflammation and cardiac dysfunction are associated with AKI in MIS-C patients; and the association with age in this group merits further studies in larger groups. Early outcome is favorable; long-term follow-up for kidney functions is needed.

Editorial on the Special Issue "Advances in Pediatric Acute Kidney Injury"

Acute kidney injury (AKI) refers to a swift decline in kidney function, marked by the reduced excretion of waste products and disturbances in fluid and electrolyte balance [...].

A Tale of Two Pathologies: MIS-C in a Patient with Pediatric Systemic Lupus Erythematosus

An HIV-negative 9-year-old female was admitted to the pediatric ward at a tertiary hospital in Johannesburg, South Africa for investigation of a suspected rheumatic disorder complicated by proteinuria. She was subsequently diagnosed with pediatric systemic lupus erythematosus complicated by class IV lupus nephritis. Further into her admission, the patient developed hospital-acquired SARS-CoV-2 infection with mild clinical symptoms. Three weeks after her initial COVID-19 diagnosis, the patient developed multisystemic inflammatory syndrome. She was successfully treated with intravenous immunoglobulin therapy, intravenous corticosteroids, and thromboprophylaxis.

Pediatric glomerulopathy after COVID-19 vaccination: A case series and review of the literature

BACKGROUND

Cases of glomerulopathy after COVID-19 vaccination have been reported in the adult population, while only a few cases have been reported in children and adolescents. For better understanding of this association in pediatric population, we aimed to describe clinical course of patients with glomerulopathy within 60 days of COVID-19 vaccination who were under followed up in the pediatric nephrology department of National Taiwan University Children's Hospital.

METHODS

We reviewed the clinical characteristics, vaccine types, and outcomes of patients with newly diagnosed glomerular diseases or relapse of underlying glomerulopathy within 60 days after COVID-19 vaccination at our facility between January 2021 and July 2022.

RESULTS

Thirteen pediatric patients were found to have newly diagnosed glomerular diseases or relapse from their underlying glomerulopathy after receiving their first, second, or third COVID-19 vaccines in our facility. Of the five pediatric patients with newly diagnosed glomerulopathy after vaccination, thin basement membrane nephropathy, idiopathic nephrotic syndrome, and hematuria have been identified. Seven patients had relapse episodes of underlying nephrotic syndrome and one patient with underlying isolated microscopic hematuria developed subnephrotic proteinuria after COVID-19 vaccination. All patients experienced remission or improvement with either immunosuppressive or conservative treatment during the follow-up period.

CONCLUSIONS

This is the largest case series to date of pediatric glomerulopathy after COVID-19 vaccination. From our report, patients with either newly diagnosed or relapse of glomerulopathy after vaccination had good outcomes, and receiving vaccination to prevent COVID-19 infection or complications should be encouraged in pandemic era under close monitoring kidney manifestations.

Renal Involvement in Multisystem Inflammatory Syndrome in Children: Not Only Acute Kidney Injury

Kidney involvement has been poorly investigated in SARS-CoV-2 Multisystem Inflammatory Syndrome in Children (MIS-C). To analyze the spectrum of renal involvement in MIS-C, we performed a single-center retrospective observational study including all MIS-C patients diagnosed at our Pediatric Department between April 2020 and May 2022. Demographic, clinical, pediatric intensive care unit (PICU) admission's need and laboratory data were collected at onset and after 6 months. Among 55 MIS-C patients enrolled in the study, kidney involvement was present in 20 (36.4%): 13 with acute kidney injury (AKI) and 7 with isolated tubular dysfunction (TD). In eight patients, concomitant AKI and TD was present (AKI-TD). AKI patients needed higher levels of intensive care (PICU: 61.5%, p < 0.001; inotropes: 46.2%, p = 0.002; second-line immuno-therapy: 53.8%, p < 0.001) and showed lower levels of HCO3- (p = 0.012), higher inflammatory markers [neutrophils (p = 0.092), PCT (p = 0.04), IL-6 (p = 0.007)] as compared to no-AKI. TD markers showed that isolated TD presented higher levels of HCO3- and lower inflammatory markers than AKI-TD. Our results indicate a combination of both pre-renal and inflammatory damage in the pathogenesis of kidney injury in MIS-C syndrome. We highlight, for the first time, the presence of tubular involvement in MIS-C, providing new insights in the evaluation of kidney involvement and its management in this condition.

Case Report: Multisystem inflammatory syndrome in children with associated proximal tubular injury

Introduction

SARS-CoV-2 infection in the pediatric population can be associated with a multiorgan inflammatory syndrome called children's multisystem inflammatory syndrome (MIS-C). The kidneys can be affected by a broad spectrum of possible injuries, whose pathogenetic mechanisms are still unclear.Case report: We report the case of a 5-year-old boy with severe cardiac involvement in the context of MIS-C. After two weeks of hospitalization, an abdominal ultrasound showed massive bladder "debris", followed by the onset of normoglycemic glycosuria. Over time, there was a progressive increase in glycosuria, and the presence of a mat of amorphous phosphate crystals was evidenced on urinary sediment. Together with the findings of hypo-uricemia, increased urinary uric acid, and globally increased urinary amino acids, a clinical picture of kidney proximal tubular damage with secondary Fanconi-like syndrome took shape.

Discussion

This case report describes the case of a patient with MIS-C with cardiac and kidney involvement characterized by proximal tubular damage, which slowly improved but still persisted at the 8-month follow-up. The pathogenesis of the damage is unclear and probably multifactorial.

Update on the treatment of multisystem inflammatory syndrome in children associated with COVID-19

In late 2019, SARS-CoV-2 was detected in China and spread worldwide. In rare cases, children who were infected with COVID-19 may develop multisystem inflammatory syndrome (MIS-C), which could have higher mortality than COVID-19 itself. Therefore, diagnosis and management are critical for treatment. Specifically, most of the initial treatment options of MIS-C choose intravenous immunoglobulin (IVIG) and steroids as the first-line treatment for patients. Moreover, antagonists of some cytokines are used as potential future therapeutics. Of note, therapeutic plasmapheresis can be used as a treatment for refractory severe MIS-C. We believe that each patient, especially those with comorbid conditions, should have individualized treatment based on both multidisciplinary consensus approach and expert opinion.

Clinical presentation and short-term outcomes of multisystemic inflammatory syndrome in children in Lagos, Nigeria during the COVID-19 pandemic: A case series

Background

Multisystemic inflammatory syndrome in children (MIS-C) has increasingly been documented globally with the progression of the COVID-19 pandemic and a significant proportion of cases have been noted in children of Black descent. There has been a noticeable discrepancy in the presentation and outcomes of COVID-19 infection in sub-Saharan Africa compared to the rest of the world. We documented the demography, clinical features, laboratory and imaging findings, therapeutic management, and short-term outcomes of paediatric patients with MIS-C diagnosed during the COVID-19 pandemic in Lagos, Nigeria.

Methods

We carried out a retrospective review of MIS-C cases seen in nine public and private hospitals in Lagos from July 10, 2020 to July 30, 2021. Data on clinical presentation, laboratory investigations, therapy as well as outcomes at 2 weeks, 6 weeks, 3 months and 6 months were analyzed.

Findings

28 children and adolescents with median age of 7·5 (IQR 2·3 - 9·4) years were diagnosed with MIS-C. MIS-C was suspected in 24 patients (85·7%) at initial clinical evaluation and mucocutaneous, gastrointestinal and cardiovascular manifestations were identified in 75·0%, 71·4% and 89·3% of patients respectively. Acute kidney injury and aseptic meningitis were noted in 32·1% and 17·9% of patients respectively. Cardiac manifestations at presentation included coronary dilatation and pericardial effusion in 46·4% each, ventricular dysfunction (32·1%), atrioventricular valve regurgitation (25·0%), prolonged QTc interval (40·0%) and first-degree atrioventricular block (16·0%). Therapy included aspirin in 89·3%, steroids in 75·0% and intravenous immunoglobulin (IVIG) infusion in 60·7%. All patients survived and were discharged after a mean of 11·14 (SD 5·65) days. Frequency of coronary dilatation had reduced from 46·4% to 7·1% by 3 months follow up and prolonged QTc interval persisted until the 6 week follow up in 4.5% of patients. Echocardiogram and electrocardiogram findings were normal in all patients assessed at 6 months follow up.

Interpretation

MIS-C is an important diagnosis in children presenting with prolonged fever during the COVID-19 pandemic. Cardiovascular manifestations occurred in several children with MIS-C and improved by 6 months follow up. Early diagnosis and prompt institution of a combination of antiplatelet therapy, steroids and IVIG appear to be beneficial.

Funding

None.

Six-month multidisciplinary follow-up in multisystem inflammatory syndrome in children: An Italian single-center experience

BACKGROUND

A severe multisystem inflammatory syndrome in children (MIS-C) related to SARS-CoV-2 has been described after infection. A limited number of reports have analyzed the long-term complications related to pro-inflammatory status in MIS-C. We evaluated multiorgan impairment at the 6-month follow-up in MIS-C.

METHODS

We enrolled 33 pediatric patients consecutively hospitalized for MIS-C and monitored for almost 6 months. The inter-relationship of patient's features and disease severity at admission with long term complications was studied by multivariate analysis.

RESULTS

Endo-metabolic derangement, cardiac injury, respiratory, renal and gastrointestinal manifestations and neurological involvement are part of the initial presentation. The most abnormalities appear to resolve within the first few weeks, without significant long term dysfunction at the 6-months follow-up, except for endocrine (non-thyroidal illness syndrome in 12.1%, insulin resistance in 21.2%) and neurological system (27.3% cognitive or psychological, behavioral, adaptive difficulties). Endocrine and heart involvement at admission represent a significant factor on the long term sequelae; however no association between severity score and long-term outcome was noted.

CONCLUSIONS

The severity of initial clinical presentation may be associated to organ domain, however it is not related to long term sequelae. The prevalent organ restoration supports a predominant indirect immune-mediated injury triggered by a systemic inflammatory response; however a direct damage due to the viral entry could be not excluded. Eventhought our preliminary results seem to suggest that MIS-C is not a long-term risk condition for children health, a longer follow-up is mandatory to confirm this hypothesis.

Are we losing awareness of other infections due to the fear of coronavirus disease-2019 and MIS-C?

INTRODUCTION

Multisystem inflammatory syndrome in children (MIS-C) is a rarely seen severe complication of coronavirus disease-2019 (COVID-19). Although fever is one of the indispensable symptoms, other infections should be considered in the differential diagnosis during the pandemic.

CASE REPORT

An 8-year-old and a 16-year-old female patient were admitted with fever, vomiting, headache. Both had fulfilled the criteria and were diagnosed with MIS-C. However, they both had remarkable persistent costovertebral angle tenderness, which was unexpected in MIS-C. In Case-1, urine analysis showed microscopic hematuria without pyuria, and urine culture showed no bacterial growth. Case-2 had microscopic hematuria and pyuria with Escherichia coli growth in urine culture. Contrast-enhanced computed tomography showed wedge-shaped hypodense multiple lesions in bilateral kidneys for Case-1, in the right kidney for Case-2. They diagnosed acute focal bacterial nephritis (AFBN).

CONCLUSIONS

The diagnostic criteria of MIS-C can overlap with the symptoms of other severe septic infections such as AFBN, which is a rare urinary tract infection, diagnosed by imaging of localized renal inflammatory mass-like or wedge-shaped lesion. A detailed anamnesis and careful physical examination may help differential diagnosis.

An 11-Year-Old Saudi Arabian Girl Who Presented with Multisystem Inflammatory Syndrome in Children (MIS-C) Associated with SARS-CoV-2 Infection with Coronary Artery Aneurysm and Cardiac Involvement: A Case Report

BACKGROUND Early in the COVID-19 pandemic, children who were infected with severe acute respiratory syndrome coronavirus2 (SARS-CoV-2) with vascular inflammation were described as having a vasculitis similar to Kawasaki's disease. There are now consensus clinical guidelines that have described the presentation and diagnosis of multisystem inflammatory syndrome in children (MIS-C) associated with SARS-CoV-2 infection. This report aims to describe a case of MIS-C in an 11-year-old Saudi Arabian girl who presented with coronary artery aneurysm and cardiac involvement. CASE REPORT We describe an 11-year-old Saudi girl who was asymptomatic for 3 weeks after contracting SARS-CoV-2. Three weeks after suffering a mild flulike illness, she developed a high fever, cough, and severe clinical deterioration within 12 h of admission, including shock, rash, pleural effusion, high inflammatory markers, and a coronary aneurysm. As per current practice, the diagnosis was confirmed as multisystem inflammatory syndrome based on a SARS-CoV-2 test with reverse transcription polymerase chain reaction (RT-PCR) from 2 nasopharyngeal aspirates. Her condition was successfully treated with antibiotics, inotropes, IVIG, aspirin, and Tocilizumab, in addition to high-flow oxygen therapy. Eventually, she was able to return home after fully recovering. CONCLUSIONS The findings in this report suggest that children with MIS-C due to SARS-CoV-2 infection can have a good prognosis, even when they suffer from coronary artery and cardiac involvement. The increasing number of emerging SARS-CoV-2 variants that affect children supports the importance of RT-PCR for the COVID-19 diagnostic test for children with multisystem or cardiovascular inflammation, which may guide the most appropriate clinical management of the variants of MIS-C.

Hematuria as an Early Sign of Multisystem Inflammatory Syndrome in Children: A Case Report of a Boy With Multiple Comorbidities and Review of Literature

Introduction: While the clinical course of SARS-CoV-2 infection seems to be milder or asymptomatic within the pediatric population, growing attention has been laid to the rare complication elicited by virus, multisystem inflammatory syndrome in children temporarily associated with COVID-19 (MIS-C). Published definition and criteria of MIS-C include persistent fever, multisystem involvement, and elevated markers of inflammation, without obvious microbial inflammation or other plausible diagnosis. However, the aim of this case report is to emphasize the diversity of symptoms of MIS-C, beyond the defined criteria. Case Presentation: We present a 10-year-old boy with 8p23.1 microdeletion syndrome and multiple comorbidities who initially came to our attention due to hematuria, persistent fever, rash, and elevated markers of inflammation. Within the next 2 days, his condition worsened despite the broad-spectrum antibiotic therapy. Assuming his past history of SARS-CoV-2 exposure, MIS-C was suspected. A high level of clinical suspicion was further supported by significant clinical features (vomiting, abdominal pain, conjunctivitis, arrhythmia, and mild left ventricular systolic dysfunction with pleural effusion) along with laboratory findings (elevated ESR, CRP, proBNP, D-dimers and fibrinogen, positive IgG SARS-CoV-2 antibodies, and negative microbiological cultures). The patient was given intravenous immunoglobulin (IVIG) and began to show instantaneous clinical and laboratory improvement. Conclusion: Despite numerous reports of MIS-C cases in children, there are still many uncertainties regarding the clinical presentation and laboratory findings, as well as mechanisms beyond this intriguing disorder. In our case, for the first time hematuria is reported as an early symptom of MIS-C. We strongly believe that reporting various manifestations and outcomes in MIS-C patients will lead to improved diagnosis, treatment, and overall understanding of this novel inflammatory condition.