Renal scarring after acute pyelonephritis

Area of Science:

• Pediatric Nephrology
• Diagnostic Imaging
• Infectious Diseases

Background:

• Acute pyelonephritis is a common childhood infection.
• Renal scarring can result from pyelonephritis, potentially leading to long-term complications.
• The incidence and risk factors for renal scarring require further elucidation.

Purpose of the Study:

• To prospectively evaluate the incidence and progression of renal scarring after acute pyelonephritis in children.
• To identify risk factors associated with renal scarring in this population.
• To assess the correlation between vesicoureteric reflux (VUR) and renal scarring.

Main Methods:

• Prospective study of 76 children (aged 0-15.9 years) with acute pyelonephritis.
• Technetium-99m dimercaptosuccinic acid (DMSA) scans performed during infection, at 2 months, and at 2 years post-infection.
• Micturition cystourethrogram (MCU) performed at 2 months to assess for VUR.

Main Results:

• Renal changes on DMSA scans were observed in 86% during infection, decreasing to 59% at 2 months and 37% at 2 years.
• Vesicoureteric reflux (VUR) was detected in 25% of children at 2 months.
• Renal scarring was correlated with gross VUR and recurrent pyelonephritis, but 62% of scarred kidneys had no VUR; older age at infection was also a risk factor.

Conclusions:

• Renal scarring after acute pyelonephritis in children is more frequent than previously recognized.
• While gross VUR and recurrent infections increase risk, renal scarring often occurs in their absence.
• The findings underscore the importance of early diagnosis and monitoring for potential long-term renal damage in children with pyelonephritis.