Risk factors associated with short- and long-term kidney injury in children with post infectious glomerulonephritis.

BACKGROUND

Post infectious glomerulonephritis (PIGN) is the most common form of acute glomerulonephritis in children. The objective of this study was to evaluate the risk factors for kidney injury in children with PIGN referred to a tertiary care center.

METHODS

This was a retrospective cohort study. The primary outcome was acute kidney injury (AKI) at initial presentation; secondary outcome was composite kidney injury, defined as reduced estimated glomerular filtration rate (eGFR), proteinuria, or hypertension at last follow-up. Binary logistic regression defined risk factors associated with the primary and secondary outcomes.

RESULTS

We identified 125 PIGN cases with a mean age of 8.3±3.5 years at presentation and 252 ± 501 days of follow-up. Sixty-six percent (79/119) presented with AKI and 57% (71/125) were admitted to hospital. Shorter time to seeing a nephrologist (OR 6.7, 95%CI 1.8-24.6), nadir C3 < 0.12 g/L (OR 10.2, 95%CI 1.9-53.7), starting an antihypertensive medication (OR 7.6, 95%CI 1.8-31.3), and nephrotic range proteinuria (OR 3.8, 95%CI 1.2-12.4) were independent risk factors for AKI when adjusted for each other. At last follow-up 35% (44/125) of the cohort had the composite outcome, with older age at presentation (OR 1.2, 95%CI 1.04-1.4) and nadir C3 < 0.17 g/L (OR 2.6, 95%CI 1.04-6.7) being independent risk factors when adjusted for AKI.

CONCLUSION

PIGN is an important cause of AKI in children and adolescents. The severity of initial illness is associated with the extent of kidney injury in both the short- and longer-term. Findings will help identify cases requiring lengthier surveillance. A higher resolution version of the Graphical abstract is available as Supplementary information.