Objective: The kidney is the second most commonly affected organ by severe acute respiratory syndrome coronavirus-2, characterized by hematuria, proteinuria, and acute kidney injury. There are few studies describing renal involvement in pediatric cases.
Materials and methods: This retrospective study evaluated the prevalence of hematuria, proteinuria, and acute kidney injury in severe acute respiratory syndrome coronavirus-2-positive pediatric cases (1-18 years old) who visited emergency department between March and November 2020. Patients with urinary tract infections were excluded. An age-specific upper limit of reference interval was used to define "elevated serum creatinine" (greater than upper limit of reference interval) and acute kidney injury (>1.5 times upper limit of reference interval).
Results: A total of 228 patients were evaluated, median age was 12.7 years (interquartile range: 7.5; 16.1), and 51.3% were male. The prevalence of asymptomatic, mild, and moderate-to-severe disease was 12.7% (29/228), 77.2% (176/228), and 10.1% (23/228), respectively. The prevalence of hematuria, proteinuria, and elevated serum creatinine was 15.8% (36/228), 6% (14/228), and 3% (7/228), respectively. Kidney involvement (i.e., at least 1 of these findings) was 23.2% (53/228) and significantly higher in the moderate-to-severe disease (43.5%). None of the patients met the acute kidney injury criterion. In logistic regression analysis, female sex (odds ratio: 1.97, 95 CI%: 1.03; 3.70, P = .040) and fever (odds ratio: 2.28, 95% CI: 1.19; 4.36, P = .012) were independent predictors of kidney involvement. Three patients demonstrated a kidney presentation (macroscopic hematuria) on admission, and another patient was diagnosed with C3 glomerulonephritis during hospitalization.
Conclusion: Kidney involvement was found about in 1 quarter of children with coronavirus disease 2019. Awareness and recognition of kidney involvement and follow-up are important in the management.