The presence of macromolecular proteins in the urine of a 1-year-old child who developed autoimmune renal injury after receiving a poor-quality measles vaccine indicates a disturbance in the kidney's filtration process, specifically at the glomerular level.
Disturbed Process of Urine Formation
Urine formation involves three main processes in the nephron:
- Glomerular filtration: Blood plasma is filtered through the glomerular basement membrane, which normally prevents large molecules like proteins from passing into the urine.
- Tubular reabsorption: Useful substances are reabsorbed back into the blood from the filtrate.
- Tubular secretion: Additional wastes are secreted into the filtrate.
The finding of macromolecular proteins in urine suggests that the glomerular filtration barrier has been compromised. Normally, this barrier restricts large proteins from entering the urine, so their presence indicates damage to the glomeruli, such as inflammation or autoimmune injury affecting the glomerular basement membrane or podocytes.
Supporting Evidence
- Autoimmune renal injury can cause glomerulonephritis, leading to increased permeability of the glomerular membrane and proteinuria (presence of proteins in urine)
- Vaccine-associated renal adverse events, including glomerulonephritis, have been reported and can manifest with proteinuria due to glomerular damage
- Macromolecular proteins in urine reflect a failure of the glomerular filtration barrier to retain these proteins, indicating disturbed glomerular filtration
Conclusion
The process of urine formation disturbed in this case is glomerular filtration , where the filtration barrier is damaged, allowing macromolecular proteins to leak into the urine. This is consistent with autoimmune glomerular injury caused by the poor-quality measles vaccine.
