Background: Nephrotic syndrome (NS) is a clinical syndrome consisting of massive proteinuria (more than 40 mg/m2 per hour), hypoalbuminemia (less than 30 g/L), hyperlipidemia, edema, and other complications. Childhood nephritis syndrome (NS) consists of proteinuria (≥40 mg/m2 /h or urine protein/creatinine ratio ≥200 mg/mL), hypoalbuminemia (<25g/L), and edema. Childhood NS is reported in 4.7 (range 1.15–16.9) per 100,000 children, with substantial variability across ethnicity and geographical location. The most useful function of Hx is heme scavenging at the systemic level, (double face of heme), which is essential for life but also highly toxic. The role of Hx in the nervous system. Hemopexin molecules cannot pass the blood–brain barrier, therefore the nervous tissue cannot utilize the plasma Hx and synthesizes its protein in situ. Furthermore, there is an importance of Hx in the immune system, as iron is one of the regulators of the immune response. Another Hx functions, not related to its heme-scavenging properties, are discussed. The mechanism of onset of relapse of MCNS caused by active Hx is unclear. Various isoforms of Hx are suggested to exist. In normal conditions, the circulating Hx is inactive. Under certain circumstances Hx becomes activated as a serine protease. MCNS in relapse demonstrates altered activity of plasma Hx. There was a decreased mean titer of plasma Hx in relapsed subjects as compared with remission