Nephrotic syndrome is a complex of clinical symptoms with various causes, which differ by age group. In children or adolescents, if it presents solely as significant proteinuria without elevated creatinine or hematuria, it is generally caused by minimal change disease. Since this type of kidney disease is sensitive to hormone treatment, it is usually possible to forego renal biopsy and start with corticosteroid therapy. For other nephrotic syndrome patients, it is advisable to first perform a renal biopsy to identify the pathological cause before considering appropriate treatment with hormones, immunosuppressants, and other medications.