[Recurrent post-infectious immune complex glomerulonephritis with persistent activation of the alternative complement...

Area of Science:

• Pediatric Nephrology
• Immunology
• Glomerular Diseases

Background:

• Recurrent upper respiratory tract infections can precede serious renal complications in children.
• Acute nephritic syndrome presents a significant challenge in pediatric cases, often requiring intensive management.
• Immune complex glomerulonephritis is a key differential diagnosis in children with nephritic syndrome.

Observation:

• A previously healthy 4-year-old boy presented with acute nephritic syndrome after recurrent upper respiratory infections, necessitating hemodialysis.
• Renal biopsy revealed post-streptococcal-like immune complex glomerulonephritis characterized by subepithelial humps, C3 deposition, and crescent formation.
• Despite initial improvement with methyl-prednisolone pulse therapy, the patient experienced two relapses within six months, requiring further immunosuppressive treatment.

Findings:

• The patient achieved normal glomerular filtration rate 21 months post-presentation but exhibited persistent glomerular proteinuria and hematuria.
• Detailed complement analyses demonstrated ongoing activation of the alternate complement pathway.
• The findings suggest a link between persistent alternate pathway activation and the long-term renal sequelae.

Implications:

• This case highlights the importance of monitoring complement activation in pediatric glomerulonephritis, particularly post-infectious types.
• Understanding persistent alternate pathway activation may lead to targeted therapeutic strategies for refractory or relapsing cases.
• Further research into the role of complement in pediatric kidney disease is warranted to improve patient outcomes.