Glycosuria in primary glomerulopathies: prevalence and prognostic significance

Abstract

Introduction: Tubular damage is common in glomerular diseases (GD). Glycosuria is a marker of tubular dysfunction and may be used to detect tubular lesion and CKD progression. The aim of this study was to evaluate the prevalence and prognostic value of glycosuria at the time of diagnosis in primary glomerulopathies (PG). Methods: We conducted a 24-month retrospective study in patients diagnosed with PG in our center between 2009 and 2020. We excluded diabetic patients, use of SGLT2 inhibitors, transplant patients, and secondary GD. Patients were divided in two groups according to their glycosuria status at diagnosis. Results: We studied 115 patients. Global prevalence of glycosuria was 10% (n=11) and membranous nephropathy (MN) had the highest prevalence (n=5, 17.9%). We found that patients with glycosuria had higher serum creatinine (2.4 vs. 1.2 mg/dL, p=0.030), higher albuminuria (4.8 vs. 1.9 g/g, p=0.004), and lower serum albumin (2.3 vs. 3.2 g/dL, p=0.021). We did not find association with histological prognostic factors. At the end of follow-up, patients with glycosuria had higher prevalence of the composite outcome of stage 5D CKD or 50% increase in basal SCr (45.5% vs. 17.3%, p=0.037). In patients with MN, results were similar but we were able to find an association of glycosuria with more severe interstitial fibrosis and tubular atrophy (25.0 vs. 0.0 %, p=0.032). Conclusion: Ten percent of our patients with PG have glycosuria. Glycosuria at the time of diagnosis was associated with more severe clinical presentation and worst renal outcome. The association with higher albuminuria suggests that tubular function has an impact on the severity and outcomes of PG.

Urinary Metabolite Profile Predicting the Progression of CKD

“… 26 Nevertheless, glycosuria in patients with glomerular disease was significantly related to pronounced tubular atrophy and interstitial fibrosis with a poorer prognosis. 27 , 28 Using the samples obtained from patients with kidney disease, urinary glucose was also found to have a significant role in representing deteriorated kidney function even after adjusting for diabetes status.…”

Adipocytes play an etiological role in renal tubular epithelial cells of db/db mice

“…In the early stage of DN, renal tubular lesions appear independently of glomerular lesions and affect the glomerulus through various pathophysiological mechanisms. Injury of renal tubular epithelial cells plays a central role in renal tubular diseases [13] . High glucose induces secretion of proin ammatory and brogenic factors in renal tubular epithelial cells through various signaling pathways.…”

Non-diabetic urine glucose in idiopathic membranous nephropathy

“…Some of these patients progressed to ESRD rapidly. Some previous researches showed that the prevalence of MN combined with glycosuria at the time of diagnose was as high as 17.9% which was higher than that of the global CKD [ 13 , 14 ]. And patients with positive urine glucose had higher serum creatinine (Scr), more urine protein, lower serum albumin, more severe interstitial fibrosis, and tubular atrophy.…”

“…And patients with positive urine glucose had higher serum creatinine (Scr), more urine protein, lower serum albumin, more severe interstitial fibrosis, and tubular atrophy. Also, the prevalence of ESRD and 50% increase in basal Scr was higher in patients with glycosuria [ 14 ]. However, there was no study about the occurrence of urine glucose during the long-term follow-up in iMN so far.…”