Some specificities in the management of hyperglycemia in patients with diabetic kidney disease.

Chronic kidney disease (CKD) is a common condition that is estimated to affect over 50 million people worldwide . Similarly, diabetes takes on epidemic proportions with global prevalence estimates of 382 million people . According to American data, in approximately 45% of incident renal replacement treatment patients, diabetes is the primary cause of their kidney failure. People with CKD due to diabetes have significantly higher incidence of cardiovascular morbidity and mortality compared to diabetics without nephropathy, and it is eighty times higher than in the general population . CKD resulted from diabetes has been termed “diabetic nephropathy” (DN). The Diabetes and Chronic Kidney Disease Work Group of the National Kidney Foundation Kidney disease Outcomes Quality Initiative (NKF KDOQI) in its Clinical Practice Guidelines and Clinical Practice Recommendatione from 2007 has suggested that a diagnosis of CKD as a consequence of diabetes should be reffered to as diabetic kidney disease (DKD). The term diabetic nephropathy should be reserved for kidney disease attributed to diabetes with hystopathological injury demonstrated by renal biopsy . The clinical diagnosis of DKD is primarily based on detection of albuminuria (proteinuria). Microalbuminuria is the term defined as an albumin/creatinine (A/C) ratio of 30–299 mg/g from a spot urine collection, or 30–299 mg/daily in the 24-hour urine collection. Macroalbuminuria is the term, defined as more than 300 mg/g or more than 300 mg/daily in the same tests respectively . The incidence of DN is estimated to be 20–40% in both type 1 and type 2 diabetes. The natural history of DN in type 1 diabetes, typically shows a period of hyperfiltration followed by microalbuminuria (30–299 mg/day) and than by macroalbuminuria (u003e300 mg/day), accompanied by a decline in glomerular filtration rate (GFR). A similar progression is though to underline the natural course of nephropathy in type 2 diabetes, but other comorbidities, including hypertension or obesity, make a progressive pattern less clear . Microalbuminuria in type 1 diabetes appears to be associated with typical histopathologycal lesions and confers risk for progression of CKD. In contrast to type 1 diabetic patients, the association between DKD and microalbuminuria is not as strong in patients with type 2 diabetes, and only 30% of them demonstrates the typical findings by kidney biopsy. However, if retinopathy is present in patients with type 2 diabetes and microalbuminuria, this is strongly suggestive of DKD, with a sensitivity of 100% and specificity of 46–62% . About 30–40% of these patients remain within microabuminuric interval, and do not progress to higher degree of albumunuria over 5–10 years of follow up. The rest of them will progress to more significant levels of albumunuria, and are likely to progress to the end stage renal disease . For the purpose of emphasizing the continuous nature of albuminuria as a risk factor, according to American Diabetes Association (ADA) recommendations, previous terms microalbuminuria and macroalbuminuria, will be rather reffered to as increased albumin excretion at levels more than 30 mg/daily .