Diabetic Kidney Disease: Past and Present

Abstract

Diabetes mellitus (DM) afflicting humans has been recognized as a disease for >3000 years. However, very little was known about its etiology and pathogenesis until about a century ago when increasing knowledge about anatomy and physiology of the human body gradually led to our understanding that the hormone insulin produced by the Islets of Langerhans in the pancreas plays a crucial role in the metabolism of glucose and maintaining the blood sugar level within a normal range. DM is caused by inadequate insulin production (type 1) or insulin resistance (type 2). For thousands of years, DM has been considered as a disease of the kidney; however, with the understanding of the pathogenesis of DM, it became clear that diabetic kidney disease (DKD) is a complication and not a cause of DM. DKD is associated with increased matrix expansion that manifests morphologically as a diffuse or nodular expansion of the mesangium and diffuse thickening of the glomerular and tubular basement membranes. Hyperglycemia plays a crucial role in the development of pathologic changes within the kidney. Once established, DKD usually undergoes a slow but relentless progression to end-stage renal disease. However, recent studies have shown that its progression can be slowed or even reversed by strict control of hyperglycemia. Morphologically, DKD may resemble several other glomerular diseases that must be ruled out before a definitive diagnosis. Patients with DM may also develop nondiabetic glomerular or interstitial diseases with or without DKD. The findings in nephrectomy specimens and the differential diagnoses are presented in detail.

How to Assess Diabetic Kidney Disease Progression? From Albuminuria to GFR

“…Diabetic nephropathy, which is another essential term referring to diabetes complications, has been frequently used as a synonym of DKD [ 9 , 16 ]. Herein, the authors would like to point out that these concepts are not equivalent, and the use of the term DN should be restricted to patients with kidney biopsy-proven diabetic lesions.…”

“…Therefore, DN is a more specific definition and confirms that diabetes is the actual cause of the pathological changes observed in the kidney. Diabetic kidney lesions create a pattern not usually seen in other renal diseases and sufficiently distinct to allow a diagnosis of DN [ 16 ]. The glomerulus is the most commonly affected structure in DN.…”

“…Nevertheless, predominant tubulointerstitial damage with mild glomerular lesions is sometimes seen in diabetic patients and is related to the renal prognosis. In type 2 diabetes, where pathological changes result from multiple comorbidities, lesions are more heterogeneous, and tubulointerstitial damage may be predominant over glomerular injury [ 16 ]. In 2010, Tervaert et al published a consensus classification of DN to establish the severity of these pathological changes [ 17 ].…”

Influence of exercise training on diabetic kidney disease: A brief physiological approach

“…Tubulointerstitial lesions in DKD are characterized by interstitial inflammation, thickening of the tubular basement membrane, tubular atrophy, and interstitial fibrosis. 13…”

Baicalin serves a protective role in diabetic nephropathy through preventing high glucose‑induced podocyte apoptosis

“…Diabetic nephropathy (DN) is a serious and harmful chronic complication caused by diabetes and it is a common cause of end-stage renal disease (1). Diabetes can cause glomerular damage, accompanied by proteinuria and subsequent tubulointerstitial lesions, which ultimately culminates in end-stage renal disease (2)(3)(4). At present, DN occurs in 20-40% of patients with diabetes (5).…”