Hyperfiltration during pregnancy or in humans born with one kidney or who lose one to trauma or transplantation generally produces NO ill consequences.
By contrast, humans who have persistent injury that destroys a comparable amount of renal tissue, progress to end-stage disease.
Clearly, there is a critical amount of primary nephron loss that produces maladaptive deterioration in remaining nephrons (renal progression). The pathologic correlate of renal progression is the relentless advance of tubular atrophy and tissue fibrosis.
The mechanism for this maladaptive response (renal progression) is the focus of intense investigation
-Hypothesis (first step): persistent glomerular injury produces local hypertension in capillary tufts, increases their single-nephron glomerular filtration rate (GFR) and engenders protein leak into tubular fluid
(source: Harrison's principles of internal medicine, page 2289)
Jadi, janganlah takut untuk derma buah pinggang =)