Serum OPG and RANKL Levels as Risk Factors for the Development of Cardiovascular Calcifications in End-Stage Renal Disease Patients in Hemodialysis.

Cardiovascular calcifications (CVC) are frequently observed in chronic kidney disease (CKD) patients and contribute to their cardiovascular mortality. The aim of the present study was to investigate the impact of osteoprotegerin (OPG)/Receptor Activator of NF-κΒ (RANK)/RANK ligand (RANKL) pathway in the development and evolution of CVCs in hemodialysis patients. In total, 80 hemodialysis patients were assessed for the presence of vascular (abdominal aorta and muscular arteries) calcifications and results were correlated to serum OPG and RANKL levels and the OPG/RANKL ratio. Traditional cardiovascular risk factors and mineral bone disease parameters were also estimated. The presence of VCs was also evaluated 5 years after the initiation of the study, and results were correlated to the initial serum OPG levels. Age, diabetes mellitus, coronary artery disease and OPG levels (p < 0.001) were associated with VCs, whereas RANKL levels were not. Multivariate analysis though revealed that only OPG levels were significantly associated with abdominal aorta calcifications (p = 0.026), but they were not correlated with the progression of VCs. Serum OPG levels are positively and independently associated with VCs in HD patients, but not with their progression. RANKL levels did not show any associations, whereas further studies are needed to establish the significance of OPG/RANKL ratio.

Impact of Τh1 and Τh2 cytokines in the progression of idiopathic nephrotic syndrome due to focal segmental glomerulosclerosis and minimal change disease.

BACKGROUND: Differential diagnosis between primary focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) is sometimes difficult as nephrotic syndrome is the main clinical symptom in both diseases. OBJECTIVES: This study has attempted to evaluate the urinary excretion of Th1 and Th2 cytokines as potential biomarkers in distinguishing the two types of nephrotic syndrome, and predicting outcome of renal function. PATIENTS AND METHODS: Thirty-six patients with FSGS (M/F 22/14, Age; 41.9 ± 17 years, SCr=1.7 ± 0.8 mg/dL, UProt=4.7 ± 5.5 g/24 h), and 21 with MCD (M/F 5/16, Age; 41.4 ± 15 years, SCr = 1 ± 0.4 mg/dL, UProt = 7.9 ± 9.3 g/24 h) were included in the study. Τh1 (IL-2, IL-12, GM-CSF, INF-γ, TNF-α) and Th2 cytokines (IL-4, IL-5, IL-10, IL-13) were measured by multiple cytokine assay, Luminex technology, in first morning urinary samples collected at the day of renal biopsy. RESULTS: No significant differences in urinary excretion of all cytokines were found between FSGS and MCD patients. In FSGS however, IL-12 urinary levels were independent factor correlated with both global sclerosis (R = 0.5, P = 0.009) and interstitial fibrosis (R = 0.5, P = 0.02). Th1 cytokines (IL-2 and GM-CSF) were significantly increased in FSGS patients who did not respond to treatment (P = 0.03 and P = 0.007, respectively). Th2 cytokines (IL-4, IL-5, IL-10, IL-13) were significantly increased in MCD patients with frequent relapses (P = 0.05, P = 0.001, P = 0.01, P = 0.03). CONCLUSIONS: Urinary excretion of Th1 and Th2 cytokines cannot discriminate FSGS from MCD. Th1 cytokines, especially IL-12, IL-2 and GM-CSF, may be involved in pathology and progression of FSGS, while Th2 cytokines are implicated in frequent relapses of nephrotic syndrome in MCD.

Up-regulation of urinary markers predict outcome in IgA nephropathy but their predictive value is influenced by treatment with steroids and azathioprine.

OBJECTIVE: Steroids and immunosuppressants can delay progression of renal function in IgAN, but their possible effect in local cytokines has not been studied. MATERIAL AND METHODS: Histology in 53 IgAN patients (M/F 35/18 age 40.5 years (17 - 65)) was evaluated using the Oxford classification system. IL-1ß, -2, -4, -5, -6, -10, -12 and -17, INF-γ and MCP-1 were measured subsequently by multiplex cytokine assay in first morning urine samples taken at the day of renal biopsy. After a 6-month course with RAASinhibitors + fish oils (FO), 35/53 patients, Group A, responded and continued on the same treatment, while in 18/53 who did not respond, Group B, steroids + azathiopine were added. RESULTS: The presence of endocapillary proliferation had significant correlation with the urinary excretion of pro-inflammatory and pro-fibrotic cytokines (IL-1ß, MCP-1, IL-17, INF-γ, IL-6 and IL-10). Serum creatinine at time of diagnosis had significant correlation with proteinuria (p = 0.02), urinary levels of IL-1ß (p = 0.03), IL-2 (p = 0.01) and MCP-1 (p = 0.03). GFR was reduced from 65 ± 29 to 57 ± 34 ml/min, p = 0.005 in Group A and remained stable in Group B patients (GFR from 63 ± 24 to 61 ± 30 ml/min, p = NS). Most of the measured cytokines in the urine predicted deterioration of renal function in Group A, but the urinary excretion of IL-6 seemed to predict renal function outcome in both groups of patients. CONCLUSION: Several cytokines are excreted in the urine of patients with IgAN, and their levels predict the outcome of the disease. Steroids + aza may exert their beneficial effect through suppression of the production or activation of most cytokines.

Steroids and azathioprine in the treatment of IgA nephropathy.

AIM: IgA nephropathy (IgAN) is a very common glomerulonephritis among young adults, but the best therapeutic approach has not been fully elucidated. This study evaluated the effect of two different treatment regimes in IgAN, steroids alone or in combination with azathioprine. METHODS: Among 122 patients with primary IgA nephropathy diagnosed in the 2000-2007 period, 22 fulfilled the inclusion criteria for the study: estimated glomerular filtration rate (eGRF) ≥30 ml/min/1.73 m(2), urine protein (Upr) ≥1 g/24 h, blood pressure (BP) <130/80 mmHg, and previous treatment with renin-angiotensin system inhibitors (RAASi) and polyunsaturated fatty acids (PFA) for at least 6 months. Patients were randomized to receive either methylprednisolone alone (MP group) or MP in combination with azathioprine (MP + Aza group) for 12 months, while treatment with RAASi + PFA continued unchanged in both groups. RESULTS: At the completion of the trial, renal function in the MP group remained stable, eGFR from 52 ± 26.7 to 53.6 ± 27.3 ml/min/1.73 m(2), p = NS, and Upr decreased from 2.4 ± 0.9 to 0.8 ± 0.5 g/24 h, p < 0.001. In the MP + Aza group, eGFR slightly increased from 57.4 ± 28.7 to 66 ± 31 ml/min/1.73 m(2), p = NS, and Upr decreased from 2.4 ± 1 to 0.7 ± 0.7 g/24 h, p < 0.001. Four patients from the MP group with partial remission at the end of the trial had a complete response when converted to Aza. Eleven patients (5 from the MP and 6 from the MP + Aza group) relapsed after stopping treatment and were restarted on lower doses. CONCLUSIONS: Both, steroid treatment alone and steroids in combination with azathioprine seem to be effective in reducing the severity of proteinuria and stabilizing renal function in IgAN. Patients who do not respond to steroids may have a better response with the combination of steroids and azathioprine.