Background
 Childhood nephrotic syndrome is a clinical entity characterized by massive loss of urinary protein (primarily albuminuria) leading to hypoproteinemia (hypoalbuminemia) and edema. The mechanism of development of childhood nephrotic syndrome is not yet clear. Kidney disease involves an interplay between inflammatory and biochemical changes with the development of innate immune response and accumulation and activation of leucocytes, particularly monocytes/macrophages in the kidney. The moncyte chemotactic protein-1 (MCP-1) is one of the CC chemokine family and it plays an important role in the recruitment of monocytes/macrophages into renal tubulointerstitium.
 
Aim of the Work
 The aim was to measure the urinary levels of MCP-1 in children with nephrotic syndrome and compare these levels in remission and relapse as well as in steroid sensitive and steroid resistant cases.  Patients and method
The study included 70 patients with nephrotic syndrome following up in Pediatric Nephrology Clinic, Ain Shams University diagnosed for at least one year and 20 age and sex matched healthy children as control group. Patients with renal impairment and secondary nephrotic syndrome were excluded from the study. Patients were divided into Group A: 35 patients in remission and Group B: 35 patients in relapse. Subgrouping according to the clinical type of nephrotic syndrome was done. Patients were subjected to thorough history taking and careful clinical examination. Routine laboratory investigations were done (s. albumin, s. creatinine, s. cholesterol, complete urialysis and urinary protein/creatinine ratio) together with quantitative determination of urinary monocyte chemotactic protein-1 in cases and controls. Results
We found a highly significant difference in urinary MCP-1 between group A, group B, and controls, the highest being group B. the levels in patients in remission still exceeded the controls significantly. However, in group B, no significant difference was found between clinical types of the disease in urinary MCP-1. The same was found in group A. no difference was found between males and females in group A as regards urinary MCP-1 levels yet females had significantly higher levels in group B. This difference was not seen in controls. We found no significant difference in MCP-1 levels in patients receiving different treatment modalities. Conclusion
 Urinary MCP-1 is a highly sensitive and specific biomarker in childhood nephrotic syndrome (98.5% and 100% respectively), being highly elevated in both remission and relapse, but is not a suitable prognostic biomarker being insignificantly different among different clinical types of nephrotic syndrome.