Abstract
Objective: In the present study, we analyzed changes in serum IgA/C3 ratio and the relationship with clinical data such as histological diagnosis, urinalysis, serum creatinine and treatment in patients with IgA nephropathy.
Materials: Eighty-one patients were diagnosed with IgA nephropathy b renal biopsy at Juntendo University.
Method: Serum IgA/C3 ratio, serum IgA, serum C3 and other clinical markers were determined these in 81 patients 6.82±2.07 years after diagnosis.
Measurement & Results: Serum IgA/C3 ratio of all patients decreased significantly from 4.33±1.67 to 3.32±0.97 (p<0.0001). In detail, serum IgA decreased from 367.89±129.03 mg/ dl to 328.69±100.36mg/ dl (p<0.0001) and serum C3 increased from 88.27±18.57mg/dl to 100.14±16.69mg/ dl (p<0.0001). Regardless of histological diagnosis, the existence of hematuria and/or proteinuria and history of steroid therapy, the serum IgA/C3 ratio significantly decreased but remained at 3.01 or higher. At the same time, serum IgA levels decreased and C3 levels increased. Only in the deteriorating renal function group, serum C3 level did not increase and was lower than that of the immutable renal function group (p=0.0207).
Conclusions: In IgA nephropathy patients, acceleration of serum IgA production is considered to decrease with progression. The fluctuation of serum C3 level suggested that C3 consumption might occur at disease onset and reflect disease activity. It appears that the serum IgA/C3 ratio became 3.01 or higher with time and might be useful in predicting the course of renal function with IgA nephropathy.
