الفهرس 
Chapter 1 : Nephrotic SyndromeOnly 14 pages are availabe for public view
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Abstract
The aim of this study:-
1-To detect the serum leptin in children with nephrotic syndrome.
2-To detect the relationship between serum leptin and degree of proteinuria.
3-To find out if it has a prognostic value or significance as regard the respond to treatment especially steroid.The first recorded description of NS dates to the15thcentury.Pediatric nephrotic syndrome, also known as nephrosis, is defined by the presence of nephrotic-range proteinuria, edema, hyperlipidemia, and hypoalbuminemia. Nephrotic range proteinuria is defined as proteinuria exceeding 1000 mg/m² per day or spot (random) urinary protein-to- creatinine ratio exceeding 2 mg/mg. The proteinuria in childhood nephrotic syndrome is relatively selective, constituted primarily by albumin (Hogg et al., 2000).
Incidence and Epdemiolgy:- Annual incidence of NS range from 2-7 per 100,000 children, and prevalence from 12-16 per 100,000 (Eddy et al., 2003).A study from New Zealand found the incidence of NS to be almost 20 cases per million children under age 15 years (Wong et al., 2007).In specific populations, such as those of Finnish or Mennonite origin, congenital nephrotic syndrome may occur in 1 in 10,000 or 1 in 500 births, respectively (Niaudet et al., 2004).ome studies have suggested a change in the histology of idiopathic nephrotic syndrome (INS) over the past few decades, although the overall incidence of INS has remained stable. The frequency of focal segmental glomeruloscleroses (FSGS) associated with INS appears to be increasing. A review of the literature suggested a 2-fold increase in the incidence of FSGS in recent decades (Borges et al., 2007).In children younger than 8 years at onset, the ratio of males to females varies from 2:1 to 3:2 in various studies. In older children, adolescents, and adults, the male-to-female prevalence is approximately equal.International study of kidney diseases in children (ISKDC) data indicate that 66% of patients with either minimal changes nephrotic syndrome (MCNS) or FSGS are male, whereas 65% of individuals with membranoproliferative glomerulonepheritis (MPGN) are female (Borges et al., 2007). Patients with MCNS, 70% are younger than 5 years. Only 20-30% of adolescents with INS have MCNS on biopsy findings. In the first year of life, genetic forms of INS and secondary nephrotic syndrome due to congenital infection predominate (Eddy et al., 2003) of glomerular capillary wall by degrading heparan sulphate glucosaminoglycans.The degradation of these anionic glycans has long been hypothesized as a cause of increased glomerular permeability to recently showed dysregulated heparanas synthesis in children with steroid-sensitive NS (Holt et al., 2005).The association of allergic responses with NS also illustrates the role of the immune system in INS. NS has been reported to occur after allergic reactions to bee stings, fungi, poison ivy, ragweed, house dust, jellyfish stings and cat fur. Food allergy might play a role in relapses of INS; a reduced-antigenic diet was associated with improved proteinuria and complete remission in one study (Coleman et al., 1996).Additionally, INS is 3-4 times more likely in children with human leukocyte antigen (HLA)-DR7. Steroid sensitive INS has also been associated with HLA-B8 and the DQB1 gene of HAL-DQW2. A greater incidence of INS is also observed in children with atopy and HLA-B12 (Niaudet et al., 2004)Leptin circulating levels directly correlate with the amount of adipose tissue mass in the body (Baumann et al., 1996).The weight-regulating effects of leptin are mediated through the full-length form of the obese reseptorsOB-R (OB-Rb) in the hypothalamus& lymphocytes (Martin et al., 2000). The biological activity of leptin is modulated by sOB-R, which is its main binding protein in serum (Lammerta et al., 2001).Leptin makes a complex with sOB-R in a molecular ratio of 1:1The biologically active form of leptin is determined by thefree leptin index (FLI), and the ratio between leptin and sOB-R levels (Schroth et al., 2001)There is a diurnal rhythm of serum leptin concentrations, the values being 20 to 40 percent higher in the middle of the night as compared with daytime( Mantzoros et al., 2001).
The kidneys play a significant role in the plasma removal of leptin. Given its size (16,000 Daltons), leptin is freely filtered by the glomerulus. However, while leptin is freely filtered, little or no leptin cleared by the kidneys appears in the urine (Meyer et al., 1997). Renal processing of leptin appears to occur through renal tubular uptake and cellular degradation (Landt et al., 1998). It was previously reported the presence of significant decrease in the prednisolone response of peripheral blood mononuclear cells (PBMCs) derived from patients with chronic renal failure, compared to the PBMCs of healthy subjects and nephrotic syndrome (NS) patients as leptin is a small peptide, it is principally cleared by the kidneys, urinary excretion of leptin in proteinuric NS patients is significantly higher, compared with healthy subjects (Kayo et al., 2008) Multiple studies revealed that the decrease in glomerular filtration rate leads to the accumulation of leptin (Menon et al., 2004).