Urinary type IV collagen excretion reflects renal morphological alterations and type IV collagen expression in patients with type 2 diabetes mellitus.
OBJECTIVE
We tried to establish the significance of quantifying urinary type IV collagen (IV-C) excretion for the evaluation of renal involvement of type 2-diabetic patients.


METHODS
Twenty patients (13 males and 7 females; age range 31 to 69 years) with type 2 diabetes mellitus had undergone renal biopsy and relationship between the severity of morphological alteration, IV-C expression and urinary IV-C excretion were examined.


RESULTS
Urinary IV-C excretion significantly correlated with mesangial expansion score (p = 0.49, p < 0.05) and tubulointerstitial injury score (p = 0.56, p < 0.05). Furthermore, urinary IV-C excretion significantly correlated with both glomerular (r = 0.56, p < 0.01) and tubulointerstitial IV-C expression areas. Urinary protein excretion also correlated with mesangial expansion score and tubulointerstitial injury score. However, it did not correlate with the expression of IV-C in the kidney.


CONCLUSIONS
These results suggest that urinary IV-C excretion reflects the pathogenetic process of diabetic nephropathy, which urinary protein excretion alone cannot do sufficiently. It can be concluded that urinary IV-C excretion could be a more useful marker for the evaluation of renal involvement of type 2-diabetic patients.
Okonogi
H
H
Department of Internal Medicine, Sakura National Hospital, Chiba, Japan.
Nishimura
M
M
Utsunomiya
Y
Y
Hamaguchi
K
K
Tsuchida
H
H
Miura
Y
Y
Suzuki
S
S
Kawamura
T
T
Hosoya
T
T
Yamada
K
K
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000652:urine; D003094:Collagen / Q000032:analysis / Q000652:urine*; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism / Q000473:pathology / Q000652:urine*; D003928:Diabetic Nephropathies / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D005260:Female; D005920:Glomerular Mesangium / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D007668:Kidney / Q000737:chemistry / Q000473:pathology*; D007678:Kidney Glomerulus / Q000737:chemistry; D008297:Male; D008875:Middle Aged
D015415:Biomarkers; D003094:Collagen