Albuminuria and insulin resistance in children with biopsy proven non-alcoholic fatty liver disease

Insulin resistance may favor increased urinary albumin excretion (UAE), leading progressively to chronic kidney disease (CKD). A recent study on non-alcoholic fatty liver disease (NAFLD), a condition of insulin resistance, associated this disease with the incidence of CKD in patients with type 2 diabetes. The aim of our study was to determine whether there is an association between insulin resistance and kidney function, based on estimates of UAE and creatinine clearance in children with biopsy-proven NAFLD. Kidney function was assessed in 80 patients with NAFLD and 59 individuals of normal weight matched for age and sex. Insulin resistance was measured by means of the homeostatic model assessment-insulin resistance (HOMA-IR) and limited to NAFLD patients by using the whole-body insulin sensitivity index. The HOMA-IR was found to differ significantly between the two groups (2.69 ± 1.7 vs. 1.05 ± 0.45; p = 0.002), while UAE (9.02 ± 5.8 vs. 8.0 ± 4.3 mg/24 h; p = 0.9) and creatinine clearance (78 ± 24 vs. 80 ± 29 mg/min; p = 0.8) did not. We found a significant but weak inverse correlation between insulin sensitivity and creatinine clearance in NAFLD patients (r _s = –0.25;p = 0.02). No difference was observed in kidney function between NAFLD children presenting with or without metabolic syndrome, low or normal HDL-cholesterol, and different degrees of histological liver damage (grade of steatosis ≥2, necro-inflammation, and fibrosis). Patients with hypertension had increased levels of UAE (p = 0.04). A longer exposure to insulin resistance may be required to cause the increase in urinary albumin excretion and to enable the detection of the effect of the accelerated atherogenic process most likely occurring in children with fatty liver disease. Longitudinal studies are needed to rule out any causative relationship between insulin resistance and urinary albumin excretion.     

Treatment of diabetic nephropathy with angiotensin II receptor antagonist

Type 2 diabetes is an ever-growing problem worldwide. Approximately 40% of the patients with type 2 diabetes will develop diabetic kidney disease. In the United States, diabetes has become the most common single cause of endstage renal disease defined by the need for dialysis or transplantation. Patients with type 2 diabetes and diabetic nephropathy have a dramatically increased cardiovascular risk. The Irbesartan Diabetic Nephropathy Trial was designed to determine whether the use of irbesartan or a calcium channel blocker would provide protection against the progression of nephropathy due to type 2 diabetes beyond that attributable to the lowering of blood pressure. In that study, 1715 hypertensive patients with nephropathy due to type 2 diabetes were randomly assigned to irbesartan 300 mg/day or amlodipine 10 mg/day, or placebo. All patients randomized in this trial had more than 900 mg of protein in their urine and serum creatinines between 1.0 mg/dl and 3.0 mg/dl. The target blood pressure was 135/85 mmHg or less in all groups. The primary outcome was time to a combined endpoint of doubling of their baseline serum creatinine concentration, the development of endstage renal disease, or death from any cause. The mean duration of follow-up was 2.6 years. Treatment with irbesartan was associated with a risk of the primary composite endpoint that was 20% lower than that in the placebo group (P = 0.02) and 23% lower than that in the amlodipine group (P = 0.006). The risk of doubling of the serum creatinine concentration was 33% lower in the irbesartan group than in the placebo group (P = 0.003) and 37% lower in the irbesartan group than in the amlodipine group (P < 0.001). Treatment with irbesartan was associated with a relative risk of endstage renal disease that was 23% lower than that in both other groups. These differences were not accounted for by differences in the blood pressures that were achieved. Proteinuria was reduced on average by 33% in the irbesartan group as compared with 6% in the amlodipine group and 10% in the placebo group. The angiotensin II receptor blocker irbesartan was shown to be effective in protecting against the progression of nephropathy due to type 2 diabetes. In a study done in patients with type 2 diabetes and early nephropathy as manifested by microalbuminuria, 590 hypertensive patients with type 2 diabetes and microalbuminuria were randomized to receive either irbesartan 150 mg/day or irbesartan 300 mg/day and followed for 2 years. The primary outcome in that trial was the time to the onset of diabetic nephropathy, defined by persistent albuminuria in overnight specimens, with a urinary albumin excretion rate that was more than 200 mg/min or at least 30% higher than the baseline level. The irbesartan 150 mg/day group demonstrated a 39% relative risk reduction versus the control group in the development of overt proteinuria. The irbesartan 300 mg/day group demonstrated a highly significant 70% risk reduction versus the control group (P < 0.001). The albumin excretion rate was reduced in the two irbesartan groups throughout the study (−11% and −38% at 24 months compared with baseline in the irbesartan 150-mg and 300-mg groups, respectively). The albumin excretion rate remained unchanged in the control group. Irbesartan was demonstrated in the above study to be renoprotective, independent of its blood pressure-lowering effect, in patients with type 2 diabetes and microalbuminuria. Thus, irbesartan, an angiotensin receptor blocker, was demonstrated to be significantly renoprotective in patients with type 2 diabetes with either early nephropathy (microalbuminuria) or late nephropathy (proteinuria). The renoprotective effects of irbesartan were above and beyond the effects irbesartan had on systemic blood pressure. Patients with type 2 diabetes and either early or late diabetic nephropathy should be treated with the angiotensin II receptor blocker irbesartan. Received: October 18, 2002 / Accepted: December 17, 2002 Correspondence to:E.J. Lewis     

Inhibitory effect of ibudilast on urinary albumin excretion in type 2 diabetes mellitus with microalbuminuria

To evaluate the clinical effect of ibudilast, a prostacyclin-mediated vasodilator and antiplatelet agent, on diabetic nephropathy, 8 nonhypertensive patients with type 2 diabetes mellitus (DM; 4 men and 4 women, mean age: 58.9 +/- 11.4 years, duration of diabetes: 16.9 +/- 3.2 years) with microalbuminuria [20-200 mg/g creatinine (Cr)] were administered ibudilast (30 mg/day) for 18 months (ibudilast group). The urinary albumin excretion index (UAE, mg albumin/g Cr) was compared with 8 age-matched type 2 DM with microalbuminuria (control group). During the study, the UAE significantly decreased in the ibudilast group, while it significantly increased in the control group. After 18 months, the UAE (52 +/- 19 mg/g Cr) in the ibudilast group was significantly (p < 0.05) lower than that (99 +/- 46 mg/g Cr) in the control group. These results suggest that ibudilast may inhibit the progression of early diabetic nephropathy in type 2 DM.     

Urinary tumour necrosis factor-alpha excretion independently correlates with clinical markers of glomerular and tubulointerstitial injury in type 2 diabetic patients.

BACKGROUND: Inflammation is a potential factor in the development and progression of diabetic nephropathy. The aim of this study was to analyse the relationship between the pro-inflammatory cytokine tumour necrosis factor-alpha (TNFalpha) and clinical markers of glomerular and tubulointerstitial damage [urinary albumin excretion (UAE) and urinary N-acetyl-beta-glucosaminidase (UNAG), respectively] in a large group of type 2 diabetic patients. METHODS: A total of 160 diabetic patients and 32 healthy controls were included in the study. High-sensitive C-reactive protein (hs-CRP) as well as serum and urinary levels of TNFalpha were measured. UAE and UNAG were determined by 24-h urine collection. RESULTS: Serum hs-CRP and TNFalpha were significantly higher in diabetic than in control subjects, as well as UAE and UNAG. Diabetic patients had increased urinary TNFalpha compared to non-diabetics [14.5 (2-29) vs 4 (0.8-12), P < 0.001]. Serum hs-CRP and TNFalpha in diabetics with increased UAE were elevated compared to diabetics having normoalbuminuria. Urinary TNFalpha was also higher in diabetic subjects with micro- or macroalbuminuria than in patients with normal UAE [10.5 (4-20) and 18 (9-29) vs 7 (2-18) pg/mg, P < 0.0001, respectively]. Multiple regression analysis showed that urinary TNFalpha (P < 0.0001), hs-CRP (P < 0.0001), serum TNFalpha (P < 0.01) and HbA1c (P < 0.05) were independent of and significantly associated with UAE, whereas duration of diabetes (P < 0.001), urinary TNFalpha (P < 0.01), HbA1c (P = 0.01), hs-CRP (P < 0.05) and serum creatinine (P < 0.05) were associated with UNAG. CONCLUSIONS: In patients with type 2 diabetes, urinary TNFalpha excretion is elevated and correlates with severity of renal disease in terms of both glomerular and tubulointerstitial damage, suggesting a significant role for TNFalpha in the pathogenesis and progression of renal injury in diabetes mellitus.     

Combination therapy of trandolapril and candesartan cilexetil reduces microalbuminuria and urinary endothelin-1 excretion in patients with type 2 diabetes

Background. Angiotensin (AT)-converting enzyme inhibitors (ACEIs) and AT1-receptor blockers (ARBs) are widely used to reduce urinary albumin excretion (UAE) and slow the progression of diabetic nephropathy. The aim of the present study was to determine whether treatment with trandolapril (an ACEI) and candesartan cilexetil (an ARB) in combination has more effect on UAE and urinary endothelin (ET)-1 excretion than treatment with trandolapril or candesartan cilexetil alone in patients with type 2 diabetes. Methods. Sixty normotensive type 2 diabetes patients with microalbuminuria were randomly assigned to four treatment groups: (A) treatreatment with trandolapril at 2 mg/day (n = 15), (B) treatment with candesartan cilexetil at 8 mg/day (n = 15), (C) treatment with trandolapril at 2 mg/day and candesartan cilexetil at 8 mg/day (n = 15), and (D) treatment with placebo (n = 15). The study period was 18 months. UAE, urinary ET-1, and plasma ET-1 levels were measured in the patients before treatment and after 12 and 18 months of treatment. Results. Before treatment, UAE, urinary ET-1, and plasma ET-1 levels differed little between the four groups. Trandolapril and candesartan cilexetil administered alone reduced UAE and urinary ET-1 excretion to a similar extent (12 months; P < 0.05 and 18 months; P < 0.01). When trandolapril and candesartan cilexetil were coadministered, UAE and urinary ET-1 excretion decreased to a significantly greater extent at 12 and 18 months (P < 0.05) than with trandolapril or candesartan cilexetil alone. However, plasma ET-1 and systemic blood pressure levels were not affected. Conclusions. The data suggest that combination therapy with trandolapril and candesartan cilexetil has an additive effect on the reduction of microalbuminuria in microalbuminuric normotensive type 2 diabetes patients. Received: December 19, 2001 / Accepted: June 12, 2002     

Glomerular structure in IDDM women with low glomerular filtration rate and normal urinary albumin excretion.

Eight women with insulin-dependent diabetes mellitus (IDDM) with low creatinine clearance rate (CCR) and normal urinary albumin excretion (UAE) were compared with three other groups of diabetic women: 19 with normal creatinine clearance rate (CCR) and UAE, 7 with normal CCR and microalbuminuria, and 7 with low CCR and microalbuminuria. The four groups were similar in age, duration of diabetes, HbA1, incidence of urinary tract infection, prevalence of bladder neuropathy, and urinary urea nitrogen excretion rate. The prevalence of hypertension was similar among the groups, although mean arterial pressure was higher in the low CCR and microalbuminuria group. Renal area index was lower in the low CCR and normal UAE groups than in the other groups of diabetic patients, but was not different from normal. Morphometric measures of mesangial expansion and estimates of arteriolar hyalinosis and global glomerulosclerosis were increased to a similar degree in the low CCR and normal UAE, normal CCR and microalbuminuria, and low CCR and microalbuminuria groups compared with the group without abnormalities of renal function. Therefore, it is likely that diabetic glomerulopathy is, at least in part, responsible for the loss of glomerular filtration rate seen in the low CCR and normal UAE patients. Thus, the definition of incipient nephropathy may have to be expanded beyond the concept of microalbuminuria if longitudinal study of such patients reveals an increased risk of the subsequent development of overt nephropathy. Finally, screening for diabetic kidney disease among IDDM patients should include determination of glomerular filtration rate and measurement of UAE and blood pressure, especially among women.     

Value of Plasma Level of Endothelin-1 and Nitric Oxide in Diabetic Nephropathy

Endothelial dysfunction is the central pathophysiologic denominator for all microvascular complications of diabetes, including nephropathy. Abnormalities of endothelin-1 and nitric oxide (NO) modulate renal structure and function in diabetes. We study the role of endothelin-1 and NO in the diabetic kidney. This study includes a total of 60 type-2 diabetic patients and 20 healthy subjects as a control group (group 1). Diabetics were classified into three groups. Group 2 included 20 patients without microalbuminuria, group 3 included 20 patients with microalbuminuria, and group 4 included 20 patients with macroalbuminuria. All individuals were subjected to history taking, physical examination, urine analysis, HbA1C test, kidney function tests, abdominal ultrasonography, and evaluation of urinary albumin concentration, nitric oxide levels, and plasma endothelin-1 (ET-1) levels. Our results showed an elevated plasma level of endothelin-1 of 4.09 ± 0.32, 5.04 ± 0.20, and 5.74 ± 0.11 pg/ml for group 2, 3, and 4, respectively, an elevated plasma level of nitric oxide in type-2 diabetic patients with early stages of diabetic nephropathy, and a decreased level in late stages of diabetic nephropathy of 40.08 ± 1.66, 46.11 ± 1.75, and 31.17 ± 2.16 μmol/l for group 2, 3, and 4, respectively. There was a statistically significant difference between all groups and the control group regarding NO and ET-1 (p < 0.001 and p < 0.001, respectively). The enhanced NO production may contribute to hyperfiltration in early diabetic nephropathy. ET-1 may have a role in microvascular damage in diabetics. Targeting the ET-1 system might be potentially beneficial in preventing and/or treating kidney disease in diabetics.     

Microalbuminuria in children with primary and white-coat hypertension

Microalbuminuria serves as an early marker of hypertension-related renal damage in adults. However, data on the prevalence of microalbuminuria in paediatric hypertensive patients in general and in children with white-coat hypertension (WCH) specifically are lacking. The aim of our study was to investigate the prevalence of microalbuminuria in children with primary hypertension (PH) and WCH, respectively. This was a retrospective case review of children with PH and WCH treated at three paediatric nephrology centres. Untreated children with either form of hypertension for whom measurements of urinary albumin excretion (UAE) had been performed were enrolled in the study. The study cohort comprised 52 children (39 boys) with hypertension (26 children with PH, 26 with WCH). Microalbuminuria (>3.2 mg/mmol creatinine) was present in 20% of children with PH and none of the children with WCH (p < 0.01). Children with PH had a higher median UAE than those with WCH (1.27 ± 1.92 vs. 0.66 ± 0.46 mg/mmol creatinine, p < 0.05). Based on these results, we suggest that children with PH have an increased prevalence of microalbuminuria, while children with WCH show no signs of hypertension-related renal damage.     

Mean glomerular volume and rate of development of diabetic nephropathy

We studied kidney glomerular structure and function in two groups of type I (insulin-dependent) diabetic subjects with 14-16 yr (group 1, n = 16) and 24-26 yr (group 2, n = 13) duration of diabetes and compared them to a group of 18 nondiabetic subjects with similar age ranges. Within each diabetic group, subjects were selected for normal kidney function (urinary albumin excretion less than 40 mg/24 h, normal blood pressure, creatinine clearance greater than 90 ml.min-1.1.73 m-2) or for nephropathy (urinary albumin excretion greater than 200 mg/24 h). Morphometric analysis of glomeruli revealed a significantly larger mean glomerular volume in subjects with nephropathy (group 2). Mesangial volumes were significantly greater in the nephropathic than the normoalbuminuric diabetic subjects in each group, but filtration surface per glomerulus was constant among all subjects. The percentage of sclerosed glomeruli was also significantly increased in the nephropathic subjects compared with the subjects with normal kidney function, in whom sclerosed glomeruli did not exceed 8%. In addition, there was a significant correlation between percentage of globally sclerosed glomeruli and glomerular volume in group 2 (rs = .79, P less than .01) but not group 1 (rs = -.20, NS) subjects. Thus, glomerular size or individual capacity for glomerular expansion may determine the rate of progression of the loss of kidney function in subjects destined to develop diabetic nephropathy.     

The role of the pediatric nephrologist in the care of children with diabetes mellitus

The pediatric nephrologist has traditionally not been involved in the care of the diabetic child since diabetic nephropathy presents in adulthood. Recent studies suggest that diabetic kidney disease develops silently during childhood. Measurement of urinary albumin excretion (UAE) allows earlier detection of patients at risk of nephropathy, often in adolescence. In addition to diabetic nephropathy, diabetic children are at risk of urinary tract infections, renal papillary necrosis, and various forms of glomerulonephritis. The role of the pediatric nephrologist in the care of the child with diabetes might include advising on the administration and interpretation of screening for UAE and the measurement and interpretation of glomerular filtration rate, and blood pressure. Children with evidence of renal dysfunction should be evaluated and treated by the pediatric nephrologist. Frequently, renal biopsy will be necessary in these patients. Future research may allow the detection of diabetic kidney disease earlier in childhood, further expanding the role of the pediatric nephrologist. In particular, early renal biopsy may eventually be used to select those patients at risk of diabetic nephropathy for specific treatment alterations.     

Dipyridamole reduces urinary albumin excretion in diabetic patients with normo- or microalbuminuria

The effect of 150 mg/day dipyridamole p.o. on urinary albumin excretion (UAE) was studied in 48 patients with diabetes mellitus without clinically discernible nephropathy. In 42 patients who were followed at an outpatient clinic, albumin/creatinine ratio (Ualb/Ucreat: mg/mmol) of untimed urine obtained from the same subjects repetitively was employed as an index of UAE. In 6 hospitalized patients, albumin excretion rate (AER) (micrograms/min) of 24-h-collected urine was determined. When followed without dipyridamole for 10.8 (the mean) months (N = 27, outpatients), the mean Ualb/Ucreat increased from 8.1 to 20.5. Of these, 11 patients with Ualb/Ucreat greater than 1.0 at the end of the observation period subsequently received dipyridamole for 4.2 months, and the ratio decreased from 49.0 to 7.3. When treated with dipyridamole for 9.0 months without a pre-treatment observation period (N = 15, outpatients), the ratio decreased from 9.8 to 5.6. AER of hospitalized patients who received dipyridamole for 10.0 days reduced from 68.0 to 21.9. All of these changes were statistically significant. Urinary beta 2 MG, blood pressure, serum creatinine and glycemic control were unaffected by the dipyridamole treatment. We conclude that dipyridamole reduces UAE in diabetic patients with subclinical level of albuminuria.     

Effect of dilazep dihydrochloride on urinary albumin excretion in patients with autosomal dominant polycystic kidney disease

Proteinuria and microalbuminuria occur with a highly variable severity and are associated with progression of autosomal dominant polycystic kidney disease (ADPKD). Dilazep dihydrochloride, an antiplatelet drug, is effective in patients with immunoglobulin A nephropathy or diabetic nephropathy. We studied whether dilazep dihydrochloride affects the urinary albumin excretion (UAE) in normotensive and hypertensive patients with ADPKD. Twelve normotensive ADPKD patients with microalbuminuria were randomly assigned to two groups: a dilazep (300 mg/day) treatment group (n = 6, group A) and a placebo group (n = 6, group B). In addition, 10 hypertensive ADPKD patients with microalbuminuria were randomly assigned to two groups: a dilazep (300 mg/day) treatment group (n = 5, group C) and a placebo group (n = 5, group D). Treatment with dilazep was continued for a period of 6 months, at the end of which the UAE was reduced form 130 +/- 52 to 46 +/- 26 microg/min (p < 0.01) in group A. There was no reduction in group C. There were no changes in UAE in placebo groups B and D. These results suggest that dilazep dihydrochloride may be effective in reducing UAE in normotensive ADPKD patients with microalbuminuria.     

Urinary N-acetyl B glucosaminidase as an earlier marker of diabetic nephropathy and influence of low-dose perindopril/indapamide combination

INTRODUCTION: Tubulointerstitial injury is both a key feature of diabetic nephropathy and an important predictor of renal dysfunction. N-Acetyl B glucosaminidase (NAG) is derived from proximal tubular cells and is widely used to evaluate tubular renal function. OBJECTIVE: The objective of this study is whether NAG can be used as an early marker of diabetic nephropathy by comparing the urinary NAG levels between healthy controls and diabetic patients and determining changes in urinary NAG excretion after treatment with low-dose combination perindopril (2 mg)/ indapamide (0.625 mg)/o.d. MATERIALS AND METHODS: A total of 50 patients (29 female) with type II diabetes mellitus applying to our diabetes outpatient clinics for the first time were included in our study (Group 1). Diabetic patients were classified into three subgroups on the basis of their duration of diabetes: Group 1A (n = 15) < or = 3 years, Group 1B (n = 19) 3 to 5 years, and Group 1c (n = 16) > 5 years. The inclusion criteria were no prior use of antihypertensive agents; blood pressure < 130/85 mmHg; urinary albumin excretion < 30 mg/day; and absence of renal failure, diabetietes, and hypertensive retinopathy. A total of 30 healthy individuals (16 female) (Group 2) were assessed as the control group. Systolic and diastolic blood pressures, HbA1c, body mass index, 24-h microalbuminuria (MAU), and NAG measurements in urine samples were performed by using colorimetric assay method in an analyzer (Roche Cobas Mira). The assay defined as fragmentation of 3-cresolsulfonphthaleinyl-N-acetyl-beta-D-glucosaminide molecule by NAG to 3-cresolsulphonphthalein and N-acetylglucosamine molecules and serum creatinine were measured in all groups. Type II diabetic patients were administered perindopril (2 mg)/indapamide (0.625 mg) combination once daily for 4 months, and urinary NAG levels were measured at the end of treatment. RESULTS: Statistically significant differences were observed between the groups 1 and 2 with respect to the levels of NAG and HbA1c (p < 0.05). In the treatment group, NAG levels decreased significantly (p < 0.05), whereas blood pressure and HbA1c levels did not change significantly (p > 0.05). In diabetic patients, pretreatment NAG were lowest in Group 1A and highest in Group 1c, although the difference between the treatment subgroups was not statistically significant (p > 0.05). CONCLUSION: Urinary NAG excretion is elevated in type II diabetic patients as compared with the healthy individuals. Perindopril/indapamide administration is effective in reducing urinary NAG excretion in these patients, and this effect seems to be independent from blood pressure and glycemia control. Presence of tubular proteinuria may be an early indicator of diabetic renal disease in patients without microalbuminuria. Perindopril (2 mg)/ indapamide (0.625 mg)/o.d. treatment may have beneficial effect on the tubulointerstitial damage in diabetic kidney disease.     

替米沙坦对糖尿病肾脏疾病患者尿足细胞排泄的影响

目的 探讨糖尿病肾脏疾病（diabetic kidney disease,DKD）患者尿足细胞排泄特征并研究替米沙坦对其干预作用.方法 前瞻性研究入选72例2型DKD患者,依据尿白蛋白与尿肌酐比值（albumin to creatinine ratio,ACR）将其分为2组.DKD 1组,30 μg/mg≤ACR＜300 μg/mg; DKD2组,ACR≥300 μg/mg,分别给予替米沙坦40 mg/d,治疗12周.选取20名健康志愿者作为正常对照组.采用免疫酶细胞化学镜检法检测单克隆抗体podocalyxin标记的尿足细胞,比较替米沙坦治疗前、后DKD患者与健康人群尿足细胞数的变化.结果 2组DKD患者收缩压、舒张压、空腹血糖、糖化血红蛋白、血肌酐、ACR和尿足细胞数差异均显著高于正常对照组（P＜0.05）,且DKD 2组患者血肌酐、ACR和尿足细胞数高于DKD 1组（P＜0.05）.替米沙坦治疗12周后,DKD 1组患者ACR下降,尿足细胞数减少;DKD 2组患者ACR和尿足细胞数无明显变化.结论 尿足细胞检测可预测早期DKD,替米沙坦可能通过保护足细胞延缓DKD进展.     

Urinary excretion of type IV collagen as a specific indicator of the progression of diabetic nephropathy

AIMS AND METHODS: This study was carried out to clarify whether the urinary excretion of type IV collagen (u-IV collagen) detected by specific radioimmunoassay, can be used as an indicator for the progression of diabetic nephropathy. RESULTS: u-IV collagen was higher in diabetic subjects with microalbuminuria and overt proteinuria than those with normoalbuminuria, IgA nephropathy, membranoproliferative glomerulonephritis, membranous nephropathy, or control normal subjects. u-IV collagen was positively correlated with serum and urinary beta(2)-microglobulin and negatively with creatinine clearance only in diabetic patients, but not in patients with other glomerular diseases. The serum type IV collagen was not different between all the groups, and not correlated with its urinary excretion. In the advanced diabetic nephropathy, immunoreactive type IV collagen was detected in glomerular basement membrane (GBM), tubular basement membrane and Bowman's capsule much more than that in the normal kidney. CONCLUSION: These findings indicated increased production and degeneration of type IV collagen in diabetic nephropathy. It is suggested that augmented turnover of type IV collagen in GBM and tubular basement membrane results in increased concentrations of free u-IV collagen. Therefore, measurement of u-IV collagen may be a useful, specific indicator of the progression of diabetic nephropathy.     

Cardiac hyperfunction in insulin-dependent diabetic patients developing microvascular complications

Cardiac function was studied by echocardiography in 80 insulin-dependent diabetic patients with no signs of ischemic heart disease and in 40 healthy control subjects. Echocardiographic findings were related to the urinary albumin excretion rate (UAE). In the diabetes group, fractional shortening of the left ventricle (FS) was 37.3% versus 34.3% (P less than .01) in the control group, whereas indices of preload and afterload were at the same levels as in control subjects. In diabetic patients with preclinical nephropathy (UAE 20-200 micrograms/min), FS was 41.1% compared to 37.0% (P less than .002) in patients with no signs of nephropathy (UAE less than 20 micrograms/min) and 34.8% (P less than .001) in patients with clinical nephropathy (UAE less than 200 micrograms/min). Furthermore, in patients with preclinical nephropathy, afterload was significantly decreased, whereas preload was at the same level as in the other two groups of UAE. In conclusion, a condition of cardiac hyperfunction has been found in diabetic patients with no signs of ischemic heart disease and seems pronounced in diabetic patients developing microvascular disease (patients with preclinical nephropathy), probably secondarily to a condition of hyperperfusion in these patients.     

Non-albuminuric renal disease among subjects with advanced stages of chronic kidney failure related to type 2 diabetes mellitus

Urinary albumin excretion has been consistently found to be normal in a significant number of subjects with early stages of diabetic kidney disease. This study was aimed to estimate the prevalence and characteristics of non-albuminuric chronic kidney disease associated with type 2 diabetes mellitus among subjects who reach advanced stages of renal failure. Study population was composed of incident patients with advanced chronic kidney disease (glomerular filtration rate <30?mL/min) related to type 2 diabetes in a tertiary hospital from Gran Canaria (Spain) during a period of 2 years. Subjects were classified as normoalbuminuric (urinary albumin-to-creatine ratio [UACR] <30?mg/g), microalbuminuric (UACR ≥30 and <300?mg/g), or proteinuric (UACR ≥300?mg/g). Of 78 eligible patients, 21.8% had normoalbuminuria, 20.5% had microalbuminuria, and 57.7% had proteinuria. Individuals with normoalbuminuria were mostly women and had a lower prevalence of smoking and polyneuropathy than subjects with microalbuminuria or proteinuria. They also presented greater measures of body mass index and waist circumference, higher values of total and LDL cholesterol, and lower values of HbA_1c and serum creatinine than subjects with microalbuminuria or proteinuria. Multivariate analysis demonstrated that female sex (positively) and HbA_1c and polyneuropathy (negatively) were independently associated with absence of albuminuria. In conclusion, around 20% of subjects with diabetes-related advanced chronic kidney disease, characteristically women, have normal urinary albumin excretion. HbA_1c and polyneuropathy are inversely related to this non-albuminuric form of nephropathy.     

Efficacy and safety of lisinopril for mild childhood IgA nephropathy: a pilot study

Even in children with mild immunoglobulin (Ig)A nephropathy (IgA-N) showing minimal/focal mesangial proliferation, persistent proteinuria seems to be a risk factor for progression of the disease, indicating the need for an effective and safe treatment even in such cases. Studies carried out to date have indicated that angiotensin-converting enzyme inhibitors (ACEIs) reduce urinary protein excretion and preserve renal function in adult IgA-N. However, no prospective study of ACEI only for childhood IgA-N has yet been carried out. In this prospective single-arm pilot trial, we administered lisinopril (0.4 mg/kg per day) as therapeutic treatment to 40 children with mild IgA-N with proteinuria [morning urinary protein/creatinine ratio (uP/Cr) ≥ 0.2 g/g]. Thirty-three patients reached the primary endpoint (uP/Cr < 0.2) during the 2-year treatment period. The cumulative disappearance rate of proteinuria determined by the Kaplan–Meier method was 80.9%. Mean uP excretion was reduced from 0.40 to 0.18 g/m²/day (p < 0.0001). Of the 40 patients treated, five (12.5%) showed dizziness, and four of these five needed the lisinopril dose reduced. However, lisinopril therapy was continued in all patients during the 2-year treatment period. No other side effect, such as cough, was observed. We conclude that the efficacy and safety of lisinopril is seemingly acceptable for the treatment of children with mild IgA-N. The participants in the Japanese Pediatric IgA Nephropathy Treatment Study Group are listed in the Appendix.     

Urinary N-Acetyl B Glucosaminidase as an Earlier Marker of Diabetic Nephropathy and Influence of Low-Dose Perindopril/Indapamide Combination

Introduction. Tubulointerstitial injury is both a key feature of diabetic nephropathy and an important predictor of renal dysfunction. N-Acetyl B glucosaminidase (NAG) is derived from proximal tubular cells and is widely used to evaluate tubular renal function. Objective. The objective of this study is whether NAG can be used as an early marker of diabetic nephropathy by comparing the urinary NAG levels between healthy controls and diabetic patients and determining changes in urinary NAG excretion after treatment with low-dose combination perindopril (2 mg)/indapamide (0.625 mg)/o.d. Materials and Methods. A total of 50 patients (29 female) with type II diabetes mellitus applying to our diabetes outpatient clinics for the first time were included in our study (Group 1). Diabetic patients were classified into three subgroups on the basis of their duration of diabetes: Group 1_A (n = 15) ≤3 years, Group 1_B (n = 19) 3 to 5 years, and Group 1_C (n = 16) >5 years. The inclusion criteria were no prior use of antihypertensive agents; blood pressure <130/85 mmHg; urinary albumin excretion <30 mg/day; and absence of renal failure, diabetietes, and hypertensive retinopathy. A total of 30 healthy individuals (16 female) (Group 2) were assessed as the control group. Systolic and diastolic blood pressures, HbA1c, body mass index, 24-h microalbuminuria (MAU), and NAG measurements in urine samples were performed by using colorimetric assay method in an analyzer (Roche Cobas Mira). The assay defined as fragmentation of 3-cresolsulfonphthaleinyl-N-acetyl-β-D-glucosaminide molecule by NAG to 3-cresolsulphonphthalein and N-acetylglucosamine molecules and serum creatinine were measured in all groups. Type II diabetic patients were administered perindopril (2 mg)/indapamide (0.625 mg) combination once daily for 4 months, and urinary NAG levels were measured at the end of treatment. Results. Statistically significant differences were observed between the groups 1 and 2 with respect to the levels of NAG and HbA1c (p < 0.05). In the treatment group, NAG levels decreased significantly (p < 0.05), whereas blood pressure and HbA1c levels did not change significantly (p > 0.05). In diabetic patients, pretreatment NAG were lowest in Group 1_A and highest in Group 1_C, although the difference between the treatment subgroups was not statistically significant (p > 0.05). Conclusion. Urinary NAG excretion is elevated in type II diabetic patients as compared with the healthy individuals. Perindopril/indapamide administration is effective in reducing urinary NAG excretion in these patients, and this effect seems to be independent from blood pressure and glycemia control. Presence of tubular proteinuria may be an early indicator of diabetic renal disease in patients without microalbuminuria. Perindopril (2 mg)/indapamide (0.625 mg)/o.d. treatment may have beneficial effect on the tubulointerstitial damage in diabetic kidney disease.     

Urinary transforming growth factor beta-1 as a marker of renal dysfunction in sickle cell disease

Renal dysfunction affects 5–18% of patients with sickle cell disease (SCD). To date, no studies have described urinary levels of transforming growth factor β-1 (TGF-β1), a marker of fibrosis, and neutrophil gelatinase-associated lipocalin (NGAL), a marker of acute/chronic kidney disease, as biomarkers in identifying patients at risk of developing renal disease in SCD. We hypothesized that SCD subjects will have increased urinary excretion of TGF-β1 and NGAL compared with healthy controls (CTR). We examined 51 SCD subjects: 42 HbSS, 8 HbSC, and 1 HbSD. Sixteen out of 42 patients with HbSS were on hydroxyurea (HU). Urinary excretion of TGF-β1 was 26.4 ± 1.5 pg/mgCr in SCD subjects vs 15.0 ± 2.4 pg/mgCr in CTR (p < 0.00001). SCD patients with hemoglobin < 9 g/dl had higher urinary TGF-β1 than patients with milder anemia (p = 0.002). Urinary TGF-β1 trended lower in HbSS patients treated with HU (23.61 ± 2.6 pg/mgCr), vs patients not on HU (27.69 ± 1.8 pg/mgCr; p = 0.055). There was no correlation between urinary TGF-β1 and microalbuminuria or estimated glomerular function. There was no difference in urinary NGAL in SCD patients vs CTR. We suggest that urinary TGF-β1 may serve as a marker of early renal injury in SCD.