Israel Medical Association Journal

Background: Idiopathic membranous nephropathy (IMN) is one of the most common causes of nephrotic syndrome (NS) in Caucasian adults. Most patients have good renal prognosis, but 30–40% may progress to end stage renal disease (ESRD). 

Objectives: To evaluate the efficacy and safety of immunosuppressive treatment (IST) in high-risk patients.

Methods: All IMN patients diagnosed by kidney biopsy from 2004–2010 were included. Clinical and laboratory data were collected at each follow-up visit. Risk assessment for renal progression classified patients as high risk if: 24 hour protein excretion > 6 g/day, estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2, and severe disabling or life-threatening clinical symptoms of NS were present.

Results: Among 290 biopsies, 37 patients (12.7%) were IMN. They were allocated to the high-risk IST group (n=16) or low-risk supportive treatment (ST) group (n=21) according to the likelihood of developing renal failure. Mean follow-up was 47 ± 17.3 months. Complete and partial remission rate was 68.7% for high-risk IST vs. 90.4% for low-risk ST. In the high-risk IST group, eGFR was significantly lower at 30 months (65.5 ± 28.6 vs. 85.3 ± 21.6 at baseline, P < 0.05). Four high-risk patients reached ESRD. In the low-risk ST group, eGFR remained stable at 30 and 60 months. 

Conclusions: This study showed a high remission rate for IMN. IST with prednisolone and cyclophosphamide provided favorable renal outcomes in most high-risk patients. The very high remission rate obtained in the low-risk patients confirms the adequacy of supportive treatment in this group.

Background: Both cigarette smoking and chronic kidney disease (CKD) are linked to cardiovascular morbidity and development of atherosclerosis. However, the relationship between cigarette smoking and renal function is not clearly understood. 

Objectives: To investigate the relationship between cigarette smoking and renal function, and determine whether the intensity of cigarette smoking influences renal function.

Methods: We conducted a retrospective analysis of subjects attending the screening center at the Rabin Medical Center. Subjects were classified as smokers, non-smokers and past smokers. Renal function was evaluated by means of the CKD-EPI equation for estimating glomerular filtration rate (eGFR). Multivariate and gender-based analyses were performed.

Results: The study population comprised 24,081 participants, of whom 3958 (17%) were classified current smokers, and 20,123 non-smokers of whom 4523 were classified as past smokers. Current smokers presented a higher eGFR compared to the non-smoking group (100.8 vs. 98.7, P < 0.001) as well as higher rates of proteinuria (15.3% vs. 9.3%, P < 0.001). The difference in eGFR between smokers and non-smokers was more significant in males than in females. Past smokers had the lowest eGFR of all groups, this difference remained significant after age adjustments (P = 0.005). 

Conclusions: Cigarette smoking is associated with higher eGFR compared to non-smoking. This difference was more pronounced in males than females, implying a gender-based difference. The higher prevalence of proteinuria in smokers suggests a mechanism of hyperfiltration, which might result in future progressive renal damage.

 

Background: Proteinuria and albuminuria are markers of kidney injury and function, serving as a screening test as well as a means of assessing the degree of kidney injury and risk for cardiovascular disease and death in both the diabetic and the non-diabetic general population.

Objectives: To evaluate the association between proteinuria below 300 mg/24 hours and albuminuria, as well as a possible association with kidney function in patients with diabetes mellitus (DM).

Methods: The medical files of patients with type 1 and type 2 DM with proteinuria below 300 mg/24 hours at three different visits to the Diabetic Nephropathy Clinic were screened. This involved 245 patient files and 723 visits. The data collected included demographics; protein, albumin and creatinine levels in urine collections; blood biochemistry; and clinical and treatment data. 

Results: The association between proteinuria and albuminuria is non-linear. However, proteinuria in the range of 162–300 mg/24 hours was found to be linearly and significantly correlated to albuminuria (P < 0.001, r = 0.58). Proteinuria cutoff, based on albuminuria cutoff of 30 mg/24 hours, was found to be 160.5 mg/24 hr. Body mass index (BMI) was the sole independent predictor of proteinuria above 160.5 mg/24 hr. Changes in albuminuria, but not proteinuria, were associated with changes in creatinine clearance. 

Conclusions: A new cutoff value of 160.5 mg/hr was set empirically, for the first time, for abnormal proteinuria in diabetic patients. It appears that proteinuria below 300 mg/24 hr is not sufficient as a sole prognostic factor for kidney failure. 

 

Background: The incidence of post-infectious glomerulonephritis (PIGN) has decreased over the last decades. As a result, recent epidemiological data from industrialized countries are scarce. 

Objectives: To evaluate patterns of PIGN in children and detect possible predictors of disease severity.

Methods: We collected clinical and laboratory data of patients with PIGN admitted to Schneider Children's Medical Center during 1994–2011. Diagnostic criteria included presence of hematuria with/without other features of nephritic syndrome along with hypocomplementemia and/or microbiological/serological evidence of streptococcal infection. Patients with other diseases (systemic lupus erythematosus, vasculitis, etc.) were excluded from the study. 

Results: A total of 125 patients with a mean age of 5.8 ± 3.3 years (range 1.5–17.6), of whom 16% were < 3 years, matched the study criteria. Presenting features included hypertension in 103 (82.4%) patients, azotemia in 87 (70.2%), fever in 49 (40%), and elevated C-reactive protein in 75 (81.5%). Isolated macrohematuria was found in 21 (16%). Full-blown nephritic syndrome was diagnosed in 51 patients (41.1%) and 28 (22.9%) had nephritic syndrome with nephrotic-range proteinuria. Depressed C3 complement levels were associated with the presence of nephritic syndrome (OR 0.73, 95%CI 0.60–0.88, P = 0.001) as well as older age (OR1.24, CI 1.08–1.43, P = 0.001). At last follow-up (mean 42 months) all examined patients (100 of 125) had normal renal function, 6 had hypertension, and 1 had proteinuria.

Conclusions: PIGN remains an important cause of glomerular disease in children and may affect very young patients. Nephrotic-range proteinuria with hypoalbuminemia seems to be more frequent than previously reported. Hypocomplementemia is associated with a more severe disease course, namely, azotemia and nephritic syndrome.