Iranian Journal of Kidney Diseases
Volume:7 Issue: 4, Jul 2013

Recently, the role of B cells in the pathogenesis of nephrotic syndrome is explained by some researchers. It has also been shown that the anti-CD20 antibody, rituximab, may be an option in the treatment of these patients. In this systematic review, we performed extensive search and identified studies on rituximab use in children with nephrotic syndrome. There are some case reports as well as larger series in this regard. The majority of these case reports and series have demonstrated the success of rituximab in the treatment of nephrotic syndrome, especially in pediatric patients with steroid-dependent and frequent-relapsing nephrotic syndrome. Nevertheless, the treatment strategies before and after rituximab infusion are not clear to date. On the other hand, it is believed that positive results on rituximab use in nephrotic syndrome are much more reported by researchers than the negative results and this is an important bias. Although most reports on rituximab use in pediatric patients have not recognized significant side effects, the long-term adverse events of rituximab are not known. Thus, controlled long-term studies are required to be done to assess the risk-benefit profile of rituximab in childhood nephrotic syndrome.

The recurrence rate of focal segmental glomerulosclerosis after kidney transplantation is ranging between 20% and 40%. Focal segmental glomerulosclerosis is associated with poor graft survival. In this review, the etiology, pathogenesis, clinicopathological features, risk factors of recurrence, and updated lines of management are discussed.

Hypercalciuria is the most common identifiable metabolic cause of calcium kidney calculus disease. Idiopathic hypercalciuria is defined as hypercalciuria with normal serum electrolytes levels in the absence of any known underlying disease responsible for increased urinary calcium excretion. The aim of the present survey was to study the prevalence of urinary tract signs and symptoms of idiopathic hypercalciuria in a healthy group of primary school children living in Rasht, a city in north of Iran. The prevalence of idiopathic hypercalciuria in our study was estimated to be 5.6%. This is a first report of idiopathic hypercalciuria in Guilan province.

The aim of this study was to determine the prevalence of albuminuria and its correlates and investigate disease management for patients with type 2 diabetes mellitus in Ahvaz. This was a cross-sectional study on the 350 patients with type 2 diabetes mellitus attending the Diabetes Clinic at Golestan Hospital, from October 2010 to September 2011. Demographic characteristics were recorded and height, weight, and blood pressure were measured. Blood urea nitrogen and serum levels of creatinine, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglyceride, and glycosylated hemoglobin A were measured in fasting blood samples. Spot urine and 24-hour urine collection were tested for albumin and kidney ultrasonography was done. A total of 72 of 350 patients (20.6%) had microalbuminuria and 18 (5.1%) had macroalbuminuria. Elevated serum creatinine was seen in 6.9% and azotemia in 6.0%. In multivariable analysis, blood urea nitrogen level, glycosylated hemoglobin A, and duration of diabetes mellitus were associated with urinary albumin excretion (P =. 04). A small proportion of the participants achieved optimal treatment goals for modifiable risk factors. Abnormal urinary albumin excretion is seen in one-quarter of type 2 diabetic patients and a small but important number of them have azotemia. Albuminuria was found to be associated with long-term duration of diabetes mellitus, poor glucose control (revealed by high glycosylated hemoglobin A levels), and high blood urea nitrogen. Poor glycemic control may have a significant role in the progression of diabetic nephropathy in these patients.

Adrenomedullin (AM) is a 52-amino acid peptide that causes vasodilatation by increased synthesis of nitric oxide. Its production by different cells such as cardiac myocytes, smooth muscle, endothelial, and oncogenic cells is stimulated by inflammatory processes. It has been shown that in the presence of inflammation in the urinary system, concentration of AM increases. In this study, we measured urinary AM in children with acute pyelonephritis before and after treatment and compared its level with that in healthy children. In a case-control study, 31 children with clinical and paraclinical documentation of pyelonephritis (case group) and 30 healthy children without pyelonephritis or other infections (control group) were studied. Urinary AM were measured on spot urine samples by high-performance liquid chromatography, and creatinine was measured by spectrophotometry to report the AM-creatinine ratio. Urinary AM- creatinine ratios were 61.3 ± 119.4 pg/mg and 4.26 ± 11.4 pg/mg, respectively, in the case and control groups (P =. 01). After treatment of pyelonephritis in the patients of the case group, this ratio decreased to 13.1 ± 21.9 (P =. 048). The coefficient correlation between urinary AM and leukocytes count was 0.252 (P =. 17). Urinary AM levels were 1896 ± 1748 pg/dL and 391 ± 477 pg/dL in the patients with 4+ versus negative C-reactive protein levels, respectively (P =. 008).

Obesity is a growing problem worldwide and is likely a major cause of the increased prevalence of high blood pressure in children. The aim of this study was to investigate the frequency of pediatric obesity and its association with hypertension in a sample of children and adolescents in Fars province (south of Iran). This cross-sectional study was carried out in Shiraz during a period from 2010 to 2011. A total of 2000 healthy students aged 11 to 17 years were included. Data on weight, height, systolic and diastolic blood pressure (measured 3 times with 5-minute intervals), and parental history of hypertension and educational level were obtained. The 95th percentile body mass index for age and sex was considered obesity. Overall, 7% and 11.8% of the students were obese and hypertensive, respectively. Blood pressure was associated with body mass index. Maternal education level was not associated with hypertension in the child. In this study, obesity was an important risk factor for hypertension. Our data showed that prevalence of obesity has not been changed in the recent 5 years in Iran, but that of hypertension has risen significantly. The high prevalence of hypertension in overweight and obese children emphasizes the need for prevention and control of childhood obesity and hypertension in early stages.

This study aimed to investigate the effects of Rosa canina L fruit extracts on histological damages, oxidative stress, and functional disturbances induced by bilateral renal ischemia and reperfusion. Ischemia and reperfusion were induced on the kidneys of anesthetized male Sprague-Dawley rats. The rats in the reperfusion and Rosa canina groups were administered extract solvent and Rosa canina extract, respectively. In addition, in the sham group, surgery was done without ischemia. In the last 6 hours of the reperfusion period, urine sample were collected using metabolic cage and at the end of this period, blood samples were taken from the descending aorta. The kidney tissues were collected and subjected to microscopic study for histological damages, while oxidative stress was measured by determining malondialdehyde and ferric reducing/antioxidant power levels. The comparison between the reperfusion and sham groups indicated reductions in creatinine clearance, absolute excretion of potassium, urine osmilarity, and increase in absolute excretion of sodium in the reperfusion group. These changes were less pronounced with Rosa canina fruit extract. In addition, blood creatinine and urea concentrations which increased in the reperfusion group, were significantly lower in the Rosa canina group. In this group, the degree of histological damages and the level of malondialdehyde were lower than the reperfusion group, while ferric reducing/antioxidant power level was significantly higher. The findings of this study showed that Rosa canina fruit extract possesses protective effects against kidney function disturbances, oxidative stress, and histological damages.

Heart disease is one of the most common reasons of death in beta-thalassemia major. A few studies have been done in children about blood pressure changes. The aim of this study was to assess hemodynamic changes by ambulatory blood pressure monitoring (ABPM). In this cross-sectional study, 30 patients with beta-thalassemia major aged 5 to 18 years old were evaluated with 24-hour ABPM. The exclusion criteria were an ejection Fraction less than 50% and a glomerular filtration rate less than 90 mL/min/1.73 m2. Hypertension was defined as a mean blood pressure index of 1 and greater with or without load blood pressure greater than 25%. Dipper status was defined as a 10% decrease in nighttime versus daytime mean arterial blood pressure. High blood pressure was detected in 16.7% of the patients. The whole-day ABPM showed hypertension in 6.7% of the children. During daytime measurements, systolic hypertension was seen in 3.3% (load 3.7%) and diastolic in 6.7% (load 3.3%). These figures for nighttime evaluation were 6.7% (load 3.3%) and 10.3% (load 6.9%), respectively. Nondipper status was detected in 56.7% of the children. There was no significant correlation between abnormal blood pressure and age, sex, body mass index, hemoglobin, number or rates of blood transfusion, or serum ferritin level. The ABPM may be a useful instrument for early detection of hemodynamic changes in children with beta-thalassemia major.

Protein-energy malnutrition and inflammation are common and overlapping conditions in hemodialysis patients, which are associated with increased risk of morbidity and mortality. Adiponectin is an adipocytokine exclusively produced by adipose tissue. The aim of this study was to further elucidate the association between serum adiponectin levels and the nutritional status of hemodialysis patients. Seventy-three patients on hemodialysis for at least 3 months, three times weekly, without any acute illness, were divided into 2 groups of well-nourished (n = 25) and malnourished (n = 48) based on their nutritional status, measured by the subjective global assessment. Serum levels of adiponectin, albumin, blood urea nitrogen, and creatinine; body mass index; and the malnutrition-inflammation score were measured in all patients. These values were compared between well-nourished and malnourished patients. The correlations of nutritional variables with serum levels of adiponectin were determined, as well. Except for the malnutrition-inflammation score, which was significantly higher in the malnourished patients compared to the well-nourished ones (11.1 ± 3.6 versus 4.2 ± 2.0, P <. 001), no other significant differences were found between the two groups. A weak but significant positive correlation was found between the serum levels of adiponectin and subjective global assessment scores (r = 0.25, P =. 03). The results of our study point to potential utility of serum adiponectin level as an indicator of nutritional status in hemodialysis patients. Further studies are needed to clarify the role of adiponectin in the pathogenesis of malnutrition in hemodialysis patients.

As an immunosuppressive treatment, cyclosporine carries a significant risk of nephrotoxicity. In this study, we assessed the safety and efficacy of sirolimus conversion in our kidney transplant recipients. Sirolimus conversion in 99 kidney transplant recipients was evaluated. Serum level of creatinine, glomerular filtration rate (GFR), and the occurrence of adverse effects of sirolimus were evaluated at conversion time and 1, 6, 12, 24, and 36 months after conversion. The major causes of conversion were chronic allograft nephropathy and cyclosporine nephrotoxicity. The median time to conversion and follow-up were 54.7 months and 24 months, respectively. Three patients died during the study period. The acute rejection rate was 4%. In 16.6% of the patients, sirolimus was discontinued because of refractory adverse effects. No significant changes in estimated GFR and incidence of adverse effects were observed between patients with baseline estimated GFR lower or higher than 40 mL/min. Patients with early sirolimus conversion (≤ 6 months after transplant) had improvement of their GFR (59.9 ± 22.3 mL/min to 68.0 ± 15.5 mL/min, P =. 02), while kidney recipients with late conversion did not show such an improvement. The difference between GFRs in these two groups reached significant level at 12 months and stayed significant until the end of the follow-up. This study emphasizes that conversion of cyclosporine to sirolimus could be associated with stable kidney allograft function. However, cyclosporine discontinuation should be considered early when it is indicated.

Castleman disease (CD) is a rare lymphoproliferative disorder, first described in 1956. This case report describes a 27-year-old man with hyaline vascular unicentric CD, first presented with edema and hypertension. On initial evaluation for edema, 24-hour urine collection revealed 8200 mg/24 h protein excretion. Pathologic examination of the kidney specimen showed diffuse mesangial lesions with segmental subepithelial deposition. On follow-up for nephrotic syndrome, the patient experienced a feeling of a mass in his pharynx and deterioration of previous snoring, documented by neck magnetic resonance imaging. Pathology report of the excisional biopsy showed CD. Treatment with corticosteroids and partial excision can be considered as an alternative to surgery for unresectable unicentric CD. The 5-year follow-up showed that this strategy could lead to remission.

We report a 16-year-old previously healthy boy who was admitted to hospital with fever, constitutional symptoms, purpura, additive arthritis, dysentery, rapid progressive renal failure, resembling Henoch- Schuenlein purpura, accompanied with retropharyngeal abscess. Kidney biopsy revealed rapid progressive glomerulonephritis with crescent formation, without immune deposition in immune fluorescent study. Serologic study revealed positive proteinase antineutrophil cytoplasmic antibody (ANCA). Intravenous methyl prednisolone plus and cyclophosphamide pulse were administered with a diagnosis of ANCA-associated vasculitis. Serum creatinine level reduced during the treatment and the patients was discharged with good clinical condition. This was the first case in which the ANCA-associated vasculitis was presented with retropharyngeal abscess. Other unusual findings were bloody diarrhea, raised purpura, and additive arthritis in an adolescence, which are more characteristic for Henoch-Schuenlein purpura.

Hypertension is very common in kidney transplant patients; however، severe and resistant cases should raise suspicion of secondary causes. Pheochromocytomas are rare but serious tumors because of their lethal hypertensive and possible malignant nature. The diagnosis is occasionally elusive، but prompt diagnosis and localization is essential for definitive surgical management. We report a case of a patient with benign pheochromocytoma presenting largely asymptomatically، but with severe resistant hypertension، 6 years after kidney transplantation. To the best of our knowledge، this is the first case report of this type of tumor after kidney transplantation.