Estimated glomerular filtration rate and daily amount of urinary protein predict the clinical remission rate of tonsillectomy plus steroid pulse therapy for IgA nephropathy

Abstract

BackgroundThis retrospective study was designed to estimate the clinical remission (CR) rate of tonsillectomy plus steroid pulse (TSP) therapy in patients with IgA nephropathy.MethodsBased on 292 of 302 patients with IgA nephropathy treated at 11 Japanese hospitals, we constructed heat maps of the CR rate at 1 year after TSP with the estimated glomerular filtration rate (eGFR), grade of hematuria, pathological grade, number of years from diagnosis until TSP, and age at diagnosis on the vertical axis and the daily amount of urinary protein (urinary protein) on the horizontal axis. We compared subgroups usinge Student’s t test, the chi-square test with Yates correction, or Fisher’s exact probability test.ResultsThe first heat map of eGFR and urinary protein showed that the CR rate was 71 % (CR vs. non-CR, 96 vs. 40) in patients with eGFR greater than 30 ml/min/1.73 m2 and 0.3–1.09 g/day of urinary protein. However, the CR rate in patients with more than 1.50 g/day of urinary protein was approximately 30 %. The second heat map of grade of hematuria and urinary protein revealed that the CR rate is 72 % (CR vs. non-CR, 93 vs. 37) in patients with more than 1+ hematuria and 0.3–1.09 g/day of urinary protein; however, it was 28.6 % in patients with no hematuria. The third heat map of pathological grade and urinary protein demonstrated that the highest CR rate was 83 % (CR vs. non-CR, 52 vs. 11) in patients with pathological grade I or II disease and less than 1.09 g/day of urinary protein, as opposed to 22 % (CR vs. non-CR, 9 vs. 32) in patients with pathological grade III or IV disease and more than 2.0 g/day of urinary protein. The fourth heat map of the number of years from diagnosis until TSP and urinary protein revealed that the former did not influence the CR rate in patients with less than 1.09 g/day of urinary protein. However, in patients with more than 1.10 g/day of urinary protein, the CR rate of the subgroup with less than 6 years was 43 % (CR vs. non-CR; 23 vs. 54) compared to 23 % (CR vs. non-CR, 11 vs. 48; P = 0.01) in the subgroup with more than 6 years. The fifth heat map of age at diagnosis and urinary protein showed that the CR rate is approximately 72 % (CR vs. non-CR, 73 vs. 28) in patients older than 19 years at diagnosis with 0.3–1.09 g/day of urinary protein.ConclusionsThe daily amount of urinary protein is an important predictor of the CR rate after TSP in IgA nephropathy patients. Heat maps are useful tools for predicting the CR rate associated with TSP.

Haematuria Increases Progression of Advanced Proteinuric Kidney Disease

“…Mild haematuria (1–29 RBCs/high-power field) was the best predictor of renal deterioration in patients with eGFR> 60 mL/min/1.73m 2 , without severe proteinuria (<100 mg/dL), with an OR of 2.3 (95% CI, 1.2–4.3) for renal deterioration at 10-year follow up [ 25 ]. Furthermore, disappearance of both haematuria and proteinuria has been proposed as clinical remission markers on IgAN [ 26 ] and it is commonly used in clinical trials [ 20 , 27 ]. In addition, the most influential renal guidelines advised that IgAN with haematuria and minimal proteinuria may be a progressive disease [ 18 ].…”

Haematuria as a risk factor for chronic kidney disease progression in glomerular diseases: A review

“…In another study, mild haematuria was a predictor of renal deterioration in patients with an estimated glomerular filtration rate (eGFR) of >60 mL/min/1.73 m 2 , without proteinuria (<100 mg/dL) [37]. Disappearance of both haematuria and proteinuria were recently proposed as clinical remission markers in this pathology [61], and both have been used as such in recent clinical trials [62,63]. Therefore, although the majority of studies rule out a repercussion of hematuria on the renal outcome of patients with IgAN, the true role of haematuria on renal function outcome in these patients remains uncertain.…”

Long‐term follow up of pediatric immunoglobulin A nephropathy treated with tonsillectomy plus methylprednisolone pulse therapy

“…Although tonsillectomy has been advocated for the treatment of IgAN, most available data on the efficacy of tonsillectomy or TMP have predominantly been from adults . Many studies on tonsillectomy have also been carried out in conjunction with immunosuppressive medication . Hotta et al .…”

“…[11][12][13][14]22 Many studies on tonsillectomy have also been carried out in conjunction with immunosuppressive medication. [23][24][25][26] Hotta et al 11 found that TMP reduced proteinuria and improved renal function in IgAN patients during 5 year follow up, and Komatsu et al 27 found that TMP had a significant impact on the disappearance of both proteinuria and hematuria, when compared with steroid pulse treatment alone. Furthermore, a meta-analysis by Liu et al 17 suggested that tonsillectomy, not only as an adjunct treatment but also independently, has significant benefits in inducing clinical remission and reducing the rates of end-state renal disease in patients with IgAN.…”