[C1q nephropathy. Report of one case]

Area of Science:

• Nephrology
• Immunology
• Pathology

Background:

• C1q nephropathy is a rare glomerulopathy defined by mesangial C1q deposition.
• Deposits may be isolated or co-occur with immunoglobulins or complement fractions.
• Diagnosis utilizes immunofluorescence, immunohistochemistry, and ultramicroscopy revealing dense mesangial deposits and podocyte alterations.

Observation:

• Clinically presents as nephrotic syndrome (NS) or urinalysis abnormalities (proteinuria, hematuria).
• Common in children and young adults.
• Histologically mimics minimal change disease (MCD), mesangial proliferative glomerulonephritis, or focal segmental glomerulosclerosis (FSGS).

Findings:

• Nephrotic syndrome in C1q nephropathy often becomes steroid-resistant or dependent.
• Treatment typically requires immunosuppressants for remission.
• This report details a 14-year-old male with NS and a 12-year treatment evolution.

Implications:

• Understanding C1q nephropathy's clinical and histological spectrum is crucial.
• Long-term management strategies for steroid-resistant NS are vital.
• This case highlights the complex therapeutic journey in pediatric C1q nephropathy.