Overlap of nephrotic syndrome with nephritic syndrome and its relation to microscopic polyangiitis in a seventeen-year-old young female

The medical condition termed as nephrotic syndrome (NS) is defined by excessive excretion of proteins in the urine, called proteinuria, and lack of circulating albumin, called hypoalbuminemia. The value for proteinuria in NS is more than 40 mg/m^2 per hour, and the cut-off value for albumin is less than 30 g/L. A rare form of vasculitis, called microscopic polyangiitis mainly affects the kidneys and lungs. We have an instance of a seventeen-year-old girl with the involvement of the renal and central nervous systems as a manifestation of microscopic polyangiitis on the background of overlap. Renal biopsies and perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) suggested microscopic polyangiitis. After receiving cyclophosphamide and pulse steroids, the patient's symptoms resolved, and the patient was discharged. To help with early disease detection and treatment, this case emphasizes the importance of considering ANCA-associated vasculitis during diagnostic processes and highlights the concept of nephrotic-nephritic overlap.