3-hydroxyproline and Kidney-Diseases

Alport's syndrome is characterised by morphological and structural changes of the renal basement membranes. As the hydroxyproline content of isolated glomerular basement membranes is reduced in patients with Alport's syndrome, it is possible that the renal excretion of 3-hydroxproline (3-OHP), a key substrate of basement membrane collagen, may be altered in such patients. The urinary excretion of 3-OHP was determined by thin layer chromatography in 20 patients with Alport's syndrome, in healthy control subjects, and in patients with other renal diseases. These included patients with poststreptococcal glomerulonephritis, lower urinary tract infection, severe reflux nephropathy, lithium induced nephropathy, polycystic kidney disease, familiar benign haematuria, and renal graft rejection. Urinary excretion of 3-OHP was significantly higher in patients with Alport's syndrome compared with the patients with other renal diseases and the healthy control subjects. All other renal diseases investigated had 3-OHP values within the normal range. Urinary 3-OHP determination detected patients with Alport's syndrome with a high sensitivity (95.2%) and specificity (97.2%). We therefore suggest using urinary 3-OHP determinations as a simple non-invasive screening test for Alport's syndrome.

Topics: Adolescent; Adult; Age Factors; Child; Child, Preschool; Chromatography, Thin Layer; Female; Humans; Hydroxyproline; Infant; Infant, Newborn; Isomerism; Kidney Diseases; Male; Middle Aged; Nephritis, Hereditary

The renal excretion of 3 hydroxyproline (3 HYP) and 4 hydroxyproline (4 HYP) was investigated in control subjects and in patients with various renal diseases. In normal adult subjects urinary 3 HYP was 12.5 +/- 3.5 (SD) mumoles/24 hr, 4 HYP was 226 +/- 62 mumoles/24 hr and the percentage ratio 3 HYP/4 HYP 5.4 +/- 0.5. This ratio was reduced during growth because of a relative excess of 4 HYP. In patients with acute glomerular disease (n = 12) 3 HYP was increased to 17.1 +/- 5.8 mumoles/24 hr (P less than 0.01), and the ratio 3 HYP/4 HYP was 7.3 +/- 0.7% (P less than 0.01). Such an increase in 3 HYP was not observed in patients with chronic glomerulonephritis (n = 24) where 3 HYP was 9.6 +/- 5.0 mumoles/24 hr and 3 HYP/4 HYP 5.7 +/- 1.6% or with diabetic glomerulopathy (n = 6). In patients with chronic interstitial nephritis (n = 8) the 3 HYP/4 HYP ratio was decreased except in patients with polycystic renal disease (PKD) where it was increased (P less than 0.001). The daily urinary content of 3 HYP and 4 HYP was slightly altered by renal insufficiency. Urinary 3 HYP did not change significantly in patients with GN with the nephrotic syndrome whatever the histological lesion. These results indicate that urinary 3 HYP: 1) is increased when glomerulonephritis is clinically acute or subacute; 2) is increased in PKD whatever the level of renal insufficiency.

Topics: Acute Kidney Injury; Adult; Glomerulonephritis; Humans; Hydroxyproline; Kidney Diseases; Nephritis, Interstitial; Nephrotic Syndrome; Polycystic Kidney Diseases

The renal excretion of 3-hydroxyproline (3-HYP), an isomer of 4-hydroxyproline (4-HYP) found 6-10 times more in basement membrane collagen than in interstitial collagen, was investigated in control subjects and in 58 adult patients with various kidney diseases. With the exception of polykystic renal disease, all the nephropathies were investigated by renal biopsy. In normal adult subjects urinary 3-HYP was 12.5 +/- 3.5 (SD) mumol/24 h, 4-HYP 226 +/- 62 mumol/24 h and the percentage ratio 3-HYP/4-HYP 5.5 +/- 0.5. This ratio was twice as little during growth because of a relative excess of 4-HYP. In patients with acute glomerular disease (acute and subacute glomerulonephritis, lupus nephritis...) (n = 13) 3-HYP was 17.1 +/- 5.8 mumol/24 h (p less than 0.01 when compared with the normal) and 4-HYP 234 +/- 77 mumol/24 h. The ratio between the two values was 7.3 +/- 0.7 (p less than 0.001). Such an increase in 3-HYP was not observed in patients with chronic glomerulonephritis (n = 24) where 3-HYP was 9.6 +/- 5.7 mumol/24 h and 3-HYP/4-HYP 6.0 +/- 1.6, neither in patients with diabetic glomerulonephritis (n = 6). In chronic interstitial nephritis (n = 8) the 3-HYP/4-HYP ratio was decreased with the exception of polykystic renal diseases (PKD), where it was increased (p less than 0.001). The daily urinary contents of 3-HYP and 4-HYP were slightly altered by renal insufficiency. In glomerulonephritis with nephrotic syndrome whatever the histological lesions, urinary 3-HYP did not change significantly. These preliminary results indicate that urinary 3-HYP (1) is increased when glomerulonephritis is clinically acute or subacute; (2) is increased in PKD suggesting a possible inborn error of collagen metabolism.

Topics: Adolescent; Adult; Creatinine; Glomerulonephritis; Humans; Hydroxyproline; Infant; Kidney Diseases; Metabolic Clearance Rate