The impact of the COVID-19 pandemic on the incidence and clinical course of acute post-streptococcal glomerulonephritis in children – single-centre experience

Introduction:
During the SARS-CoV-2 pandemic, a decrease in acute post-streptococcal glomerulonephritis (APSGN) cases was observed; however, as the pandemic subsided, reports of an increased number of diagnosed APSGN cases in the paediatric population emerged. The aim of our study was to compare the number of cases and the patient profile diagnosed with acute post-streptococcal glomerulonephritis in our centre before and after the COVID-19 pandemic.

Material and methods:
A retrospective study included 47 patients (21 females, 26 males) diagnosed with APSGN, hospitalised in our centre between 2013–2023. The parameters were compared between the group of patients diagnosed before and after the pandemic. Age at day of diagnosis, history of previous possible streptococcal infection, antistreptolysin O (ASO), C3, epidermal growth factor receptor levels at admission, the presence of the features of nephritic syndrome, the need for pharmacological treatment, and renal replacement therapy were analysed. Additionally, anthropometric measurements the C4 complement component were determined.

Results:
From 2013 to 2022, the average number of diagnosed APSGN cases per year was 3.67, increasing to 7 cases per year since 2022. A statistically significant difference in ASO level values at admission was observed between patients diagnosed with post-streptococcal glomerulonephritis before the pandemic (767 IU/ml) compared to those diagnosed after the pandemic (1362 IU/ml). No other statistically significant differences were found in the patient profile analysis.

Conclusions:
During the COVID-19 pandemic, no cases of APSGN were observed in our centre, probably due to the implemented personal protective measures and population isolation. After the COVID-19 pandemic, there was an increase in APSGN cases among children. The patient profile with diagnosis before and after the pandemic in terms of most parameters does not differ. The only significant difference was observed in ASO levels, which were higher in patients diagnosed after the pandemic compared to those diagnosed before the pandemic. Further research is needed.