Objective: Acute kidney injury is common condition in the neonatal intensive care unit and it is associated with poor outcome. The incidence of neonatal AKI is the highest one followed by adults and children, depending on different factors such as the gestational age, birth weight, contributing conditions and the facilities of the neonatal intensive care unit. The aim of the study was to determine the incidence, risk factors and the outcome of the neonatal acute kidney injury.
Subjects and Methods: This was a clinical, prospective study that was performed in a referent NICU at the University Children′s Hospital in Skopje. All neonates admitted from January 2012 to December 20014 with documented acute kidney injury were included. The medical data records of the admitted neonates with AKI were analyzed. The material was statistically processed using methods of the descriptive statistics.
Results: During the study period 770 newborn infants were admitted to the NICU and 50 (6.5%) infants developed acute kidney injury. The male to female ratio was 2.1:1. Most of the neonates involved in the study were neonates born at term (62%). Oliguric AKI was found in 28 cases (56%) and no oliguric in 22 cases (44%). The prevalence of prerenal, renal and post renal AKI were 78.5%, 19.5% and 2.0% respectively. Perinatal asphyxia was the most common predisposing factor for AKI and was evaluated in 38% of the cases with predominance of term infants and male. The mortality rate was 32% and was significantly higher in the group of patients with congenital heart diseases.
Conclusion: AKI is a life threatening condition with still high mortality rate. Early recognition of the risk factors and the rapid effective treatment of the contributing conditions will reduce AKI in the neonatal period.
In the last two decades a great progress was observed in understanding of podocytes, their specific structure and function identifying many specific podocyte proteins, such as nephrin and podocalyxin. Podocytes form the final barrier to plasma proteins leakage. Nephrin as a main component of the filtration diaphragm forms a physical barrier while podocalyxin as sialoglycoprotein forms an electrostatic barrier. Podocyte damage, i.e. podocytopathies and their loss through urine-podocyturia, are crucial in pathogenesis and progression of nephropathies with proteinuria as main clinical manifestation. In podocytopathies, nephrin and podocalyxin appear in the urine before proteinuria and microalbuminuria which were previously considered as earliest markers of nephropathies. Nephrinuria and podocalyxuria indicate damage of the podocytes on glomerular level and/or presence of apoptotic and necrotic podocytes in urine. These urinary markers are also important in early diagnosis of secondary nephropathies such as diabetic, lupus and hypertensive nephropathy as the most common causes of end-stage renal failure (ESRF). These markers are also important in the prediction of preeclampsia, which is the most common complication in pregnancy. In this review we elaborate in dept the main structural and functional features of podocytes and their specific proteins, nephrin and podocalyxin, summarizing the recent literature data on their importance in the early diagnosis of the most common secondary nephropathies.
Distal renal tubular acidosis (dRTA) (MIM #267300, #602722 and #179800) is a rare inherited tubulopathy characterized by the inability of the distal tubule to acidify the urine with consecutive systemic acidosis. The clinical features include polyuria, polydipsia, poor appetite, failure to thrive, short stature and rickets. Prominent biochemical features are hypokalemia, hypercalciuria and hypocitraturia. There are reports on patients who presented with unusual biochemical features such as low molecular proteinuria, hypophosphatemia, hypouricemia, generalized hyperaminioaciduria, hyperoxaluria and other making diagnostic confusion to the clinicians. In this work, we report on a series of 8 children with clinically, biochemically and genetically proven dRTA who present with low molecular proteinuria at the disease onset. With metabolic compensation of the disease, there was complete resolution of the low molecular weight protenuria and other proximal tubular abnormalities in all children. Late recognition of the disease with long standing hypokalemia and acidosis may result in abnormal expression and function of the transporters in the proximal tubules. Sodium dodecyl sulphate polyacrylamide gel electrophoeresis is an accurate method for detection and follow up of patients with low molecular weight proteinuria.
Diabetic nephropathy (DN) is a leading cause of end-stage renal disease. Progressive damage and decline in the number of podocytes often occur in the early stages of DN. Thus, nephrin as a podocyte-specific protein may be regarded as a potential biomarker of early detection of DN. The aim of this study is to determine whether urinary nephrin is an earlier marker in DN than microalbuminuria and to test the significance of urinary nephrin as a marker for early detection of DN.
Our cross-sectional study included 90 patients with type 2 diabetes mellitus (T2DM), 30 patients with diagnosed DN and 60 patients without diagnosed DN. As a control group, we used 30 healthy subjects. All patients with T2DM were classified into three subgroups according to urinary microalbumin/creatinine ratio (UMCR): normoalbuminuric, microalbuminuric and macroalbuminuric patients. Nephrin in urine was measured by immunoenzyme assay, microalbumin with turbidimetric and creatinine with the photometric method. In blood sera, we measured a few standard biochemical parameters.
Nephrinuria was found to be present in 100% of patients with T2DM and macroalbuminuria, in 88% with microalbuminuria, as well as 82% of patients with T2DM and normoalbuminuria. A concentration of urinary nephrin was significantly increased in all groups of subjects with T2DM compared to the control group (p<0.05). Nephrinuria correlated statistically negative with eGFR (r=-0.54). ROC analysis showed that nephrin has a total predicted probability of 96% in patients with DN.
Urinary nephrin is earlier, more specific and sensitive marker than microalbumin in early detection of DN.
Introduction. Kidney disease is associated with many abnormalities in the oral health status as well as with alterations in salivary flow and composition. The aim of this study was to evaluate and to correlate oral clinical findings, salivary flow (SF) and salivary pH values in patients with chronic kidney disease (CKD) not yet on hemodyalisis treatment, those undergoing hemodialysis and in kidney transplant recipients.
Methods. In a cross-sectional study 90 patients were included. The cohort was composed of three groups: 30 patients with CKD (serum creatinine values under 120 μmol/L-group 1), 30 patients with CKD on hemodialysis (group 2) and 30 kidney transplanted patients (group 3). The control group consisted of 20 healthy individuals. Oral symptoms, signs and lesions: salivary volume, salivary pH and SF of stimulated and unstimulated saliva were evaluated.
Results. Among patients with CKD without dialysis treatment inverse relationship was found between uremic fetor, unpleasant taste and unstimulated SF and also between xerostomia and stimulated SF. Negative correlation between thirst and unstimulated salivary flow was found in both groups, patients with CKD on dialysis and kidney transplant group. Furthermore, in kidney-transplant patients a negative correlation was found between petechiae and SF, while in group of patients with CKD on hemodialysis the same negative correlation was registered between uremic fetor and stimulated SF.
Conclusions. Salivary flow was significantly lower in hemodialysis patients, while the highest was in the kidney-transplant recipients accompanied with improvement in the other oral clinical findings observed in our study.
Salt sensitive hypertension is known to be a contributing factor for the progression of kidney disease. This study was undertaken to investigate the role of excessive dietary salt on renal function and to evaluate the effect of valsartan and amlodipin given as a combination therapy on blood pressure and parameters specific to the renal function in salt loaded SHR rats. 48 male SHR rats at age of 20 weeks and body weight ranging between 270-350 g were used. SHR rats were divided into 3 groups: control group of rats -SHRC (n = 16) given tab water ad libitum and two salt treated groups in which tab water was replaced with a solution of NaCl (1%) from age of 8 weeks given ad libitum: SHRVAL+AMLO group (n = 16) where investigated drugs were administered at a dose of 10 mg/kg/ b.w. (valsartan) and 5 mg/kg/ b.w. (amlodipin) by gavage and SHR NaCl group (n = 16) that received saline in the same volume and the same time intervals as the SHRVAL+AMLO group. For a period of 12 weeks we have investigated the effect of the VAL+AMLO drug combination on systolic blood pressure (SBP), body weight and renal function tests. Salt loading with 1% solution in the SHR NaCl group has lead to significant increase of blood pressure, proteinuria and decrease in creatinine clearance. Combined treatment with АТ1-receptor blocker and calcium antagonist has managed to control blood pressure and ameliorated renal damage.
Introduction: Podocyte injury has been reported as an early feature of DN therefore, the assessment of podocyte injury can be accomplished by estimation of podocalyxin in urine. This study aimed to estimate the urinary podocalyxin levels and to determine the sensitivity and specificity of this biomarker for early detection of DN.
Materials and methods: A total of 90 patients with type 2 diabetes mellitus (T2DM) were included in this cross-sectional study. Sixty of them were without diagnosed DN, and 30 with diagnosed DN. A control group consisted of 30 healthy subjects. All patients with T2DM were divided into three subgroups according to urinary microalbumin/creatinine ratio (UM/CR): normoalbuminuric, microalbuminuric and macroalbuminuric patients. Urine samples, were used for measurement of podocalyxin by ELISA, creatinine and microalbumin. Fasting venous blood samples was collected for biochemical analyses.
Results: The levels of urinary podocalyxin (u-PDX) were higher in patients with T2DM compared to control subjects and a statistically significant difference among studied subgroups regarding u-PDX was found (p < 0.05). Levels of u-PDX are increasing gradually with the degree of DN (p < 0.029). u-PDX levels were positively correlated with UM/CR (r =0.227, p=0.002). A cut-off level of 43.8 ng/ml u-PDX showed 73.3% sensitivity and 93.3% specificity to detect DN in early stage. A cut-off level of 30 mg/g UM/CR showed 41.5% sensitivity and 90% specifity in predicting DN. u-PDX was elevated in 48,2% of normoalbuminuric patients.
Conclusion: Urinary podocalyxin be useful and more sensitive and specific marker in early detection of DN than microalbuminuria.