The Association Between Hyponatremia and Reflux-Related Renal Injury in Acute Pyelonephritis

Introduction: The kidney regulates sodium balance and is the principal site of sodium excretion. Sodium is unique among electrolytes because water balance, not sodium balance, usually determines its concentration. Although water balance is usually regulated by osmolality, volume depletion stimulates thirst, renal protection of water and ADH secretion. Volume reduction has priority over osmolality; volume depletion stimulates ADH secretion, even if a patient has hyponatremia. The aim of this study was to consider scar nephropathy in children with UTI and hyponatremia and compare it with children without hyponatremia.Material and Methods: 200 children with pyelonephritis were included in this case–control study as case and control groups, respectively. Subjects were selected from children referred to the pediatric clinic of our hospital in Arak, Iran. Case group included children with hyponatremia and UTI (with VUR) and control group included children with UTI (With VUR) and normal serum sodium. Data was analyzed using SPSS ver.18Results: Among 200 (100%) children in both groups, 5 children (5%) had normal sodium and reflux nephropathy and 23 children had hyponatremia and reflux nephropathy.Conclusions: Hyponatremia in children with reflux nephropathy was significantly more common than children without reflux nephropathy. The observed correlation between reflux-related injury and hyponatremia necessitates evaluation of electrolytes in children with pyelonephritis.Keywords: Pyelonephritis; Child; Hyponatremia; Vesico-Ureteral Reflux

Mean Platelet Volume as a Predictive Marker for Poor Prognosis of Acute Renal Failure in children

Introduction: Acute renal failure (ARF) is a clinical syndrome in which a sudden deterioration in renal function results in the inability of the kidneys to maintain fluid and electrolyte homeostasis. A classification system has been proposed to standardize the definition of acute kidney injury in adults. These criteria of risk, injury, failure, loss and end-stage renal disease were given the acronym of RIFLE. Our goal was to study the mean platelet volume (MPV) as a prognostic predictor of ARF in children. Mean platelet volume (MPV) is a machine-calculated measurement of the average size of platelets in blood and typically included in blood tests as part of CBC (Complete Blood Count). Since the average platelet size is larger when the body is producing increased numbers of platelets, MPV can be used to make inferences about platelet production in bone marrow or platelet destruction problems.Material and Methods: The records of 200 patients with ARF were investigated prospectively. Complete blood count including MPV, erythrocyte sedimentation rate, serum C-reactive protein and electrolytes of patients were measured and compared.Results: MPV values were low in loss (p=0.0012) and failure (p<0.005). The sensitivity and specificity of MPV for the diagnosis of loss and failure were higher than those of the other inflammation markers. MPV<8.2 fL was significantly associated with poor prognosis in renal functions.Conclusions: MPV is a fast and reliable measurement with considerable predictive value for prediction of prognosis in acute renal failure.Keywords: Acute Kidney Injury; Mean Platelet Volume; Blood Platelets; Acute Kidney Injury; Prognosis