Evaluation of the impact of the COVID-19 pandemic on children with chronic kidney diseases

The COVID-19 pandemic has caused a global crisis, death and disability, especially for those who have difficulty accessing vaccination programs and healthcare facilities. Despite vaccination policies, the emergence of new variants (delta, omicron) that can evade immunity and bring with it new waves of infection has led to significant increases in the number of cases and a concern especially in patients with underlying chronic diseases, immune systems defective, unvaccinated and high-risk patients. There are few studies in the literature examining the factors associated with COVID-19 seroprevalence and seropositivity in the pediatric population with chronic kidney disease. In this study, it was aimed to analyze the frequency of SARS-CoV-2 infection, seroprevalence, risk status in terms of virus exposure, symptom/contact histories and their relationships with SARS-CoV-2 serology in the before and after COVID-19 vaccination period of children with chronic kidney disease who were monitored at the pediatric nephrology clinic during the COVID-19 pandemic. Child patients under the age of 18, with chronic kidney disease (kidney transplant, HD/PD, Stage 2-5 CKD), who had not been vaccinated against COVID-19 were included in the study on a voluntary basis. The patients were divided into two groups. The first group was included in the study during the period when COVID-19 vaccines were not in widespread use yet (01.02.2021– 25.03.2021), and the second group during the period when COVID-19 vaccines were in widespread use (23.12.2021–07.02.2022). Demographic and clinical characteristics of the patients were obtained by retrospective examination of hospital medical records. Standard questionnaire forms were used to assess the infection exposure risks that patients encountered during the COVID-19 pandemic process during routine outpatient clinic admission or hospital admission, to question symptoms and contact situations that may be compatible with COVID-19. The anti-SARS-CoV-2 IgG antibody against the S1 domain of the SARS-CoV-2 spike protein was investigated.with a micro ELISA kit in terms of subclinical COVID-19 infection and seroprevalence detection. A total of 182 children and adolescent patients with chronic kidney disease were included in the study. 116 patients were included in the first group, the 'pre-COVID-19 vaccine' group, and 66 patients were included in the second group, the 'post-COVID-19 vaccine' group. The average age of the patients in the study was 11 years and 55% were male. Primary kidney disease diagnosis distribution was as FOLLOWS; CAKUT 33% (n:60), NS/GMN 39% (n:71), cystic kidney disease 10.4% (19), HUS 9.3% (n:17), other causes 8.2% (n:15). 54% (99/182) of the patients were kidney transplant recipients, 9.9% (18/182) underwent HD/PD, 35.7% (65/182) were compensated CKD patients. The proportion of patients receiving immunosuppressive medical treatment was 73% (134/182). 31.3% (57/182) of the patients were seropositive and 68.7% (125/182) were seronegative. SARS-CoV-2 seroporevalance was found to be 24.1% (28/116) in the pre-vaccine period and significantly higher 43.9% (29/66) in the post-vaccine period (p<0.05). Seropositivity rates were lower in kidney transplant recipients (30.3%) compared to dialysis patients (38.8%). In addition, the seropositivity rate was similar to kidney transplantation recipients in those diagnosed with compensated CKD (30.7%) (p>0.05). PCR test was performed to 53.8% (98/182) of the patients. Only 15.3% (15/98) of the patients who underwent PCR testing had positive test results. The PCR positivity rate was found to be 66% (10/15). Regardless of seropositive/seronegative, the rate of symptomatic patients was higher in the post-vaccination period compared to the pre-vaccination period (95% vs. 54%, p<0.05). The most common symptoms reported were fever (40%), cough (33%) and GI symptoms (25%), respectively. Most of the patients had the infection with mild clinical findings. The risk factors for COVID-19 exposure were; using public transportation, being in a crowded environment, close contact with a patient diagnosed with COVID-19, and admission rates to a health facility where COVID-19 patients were treated were significantly higher in the post-vaccination period (p<0.05). In contrast, the rates of compliance with the isolation rules (mask, social distance, hand washing) and staying at home rules were significantly higher in the pre-vaccination period (p<0.05). No significant correlation was found between the patients' primary kidney diagnosis, the immunosuppressive drugs they used, exposure to severe immunosuppression, and being seropositive or seronegative. Our research results shows that SARS-CoV-2 seroprevalence has gradually increased in children with comorbid diseases such as chronic kidney disease during the COVID-19 pandemic process, and there has been a significant increase in the number of cases, especially with the new variants delta and omicron becoming dominant and protective measures decreased. Our results are also related to this patient population; It shows that COVID-19 disease usually progresses with mild clinical findings, and there is no significant relationship between seropositivity and other clinical features of the patients and the medical treatments they use. Seroprevalence studies allow us to develop various strategies to prevent possible future epidemic waves and to see the effects of vaccination. The scientific figures and experiences obtained during this epidemic process can be guiding and resolving in the management of similar epidemics that may occur later. The COVID-19 pandemic process, which emerged unexpectedly, caught society unprepared in many ways and forced it to find solutions in the process. The scientific figures and experiences obtained during this epidemic process can be guiding and resolving in the management of possible similar outbreaks that may occur later.