A Study on the Association of Thin Glomerular Basement Membrane Abnormality with Minimal Change Nephrotic Syndrome

ABSTRACT

PURPOSE: Thin glomerular basement membrane nephropathy (TGBMN) is recognized as the leading cause of microscopic hematuria in both children and adults. However thinning of glomerular basement membrane (TGBM) has been found in healthy adult and also is known to be associated with various renal diseases such as Alport syndrome, IgA nephropathy and mesangial proliferative glomerulonephritis. The association of TGBM with minimal change nephrotic syndrome (MCNS) has been very rare so that the present study was undertaken to determine the relationship between TGBM and MCNS. METHODS: The study population consisted of 49 children with biopsy-proven MCNS who have been admitted to the pediatric department of Kyungpook University Hospital during the past 5 years from 1997 to 2001. Group I consisted of 8 children associated with TGBM and Group II 41 children without TGBM. Various parameters such as age of illness, duration from discovery of illness to the time of biopsy, family history of hematuria and other laboratory tests were compared between these two groups and the following results were obtained. RESULTS: Age distribution showed slightly older age in Group I (7.1+/-3.5 years) compared to Group II (4.8+/-2.9 years). However this was not statistically different (P=0.056). Family history of hematuria was noted in 2 cases in Group II. Though statistically not significant, hematuria was seen in 2 out of 8 cases (25%) in MCNS children with TGBM, compared to 7 out of 41 cases (17%) with MCNS children without TGBM. Other parameters such as BUN, creatinine, 24 hours urine protein excretion, serum protein, albumin, cholesterol, and T4/T8 ratio, showed no difference. Also renal biopsy finding showed no significant difference and the thickness of glomerular basement membrane in Group I was 188 30 nm. CONCLUSION: TGBM was found in 8 out of 49 children with MCNS (16.3%). And this high frequency of occurrence indicates that these association is not an incidental findings. Typical clinical findings of TGBMN was not noted in all of the 8 children with MCNS associated with TGBM, suggesting that thinning of glomerular basement membrane (TGBN) is secondary to rather than the cause of MCNS.