[McDuffie hypocomplementemic urticarial vasculitis associated with Sjögren's syndrome]

Area of Science:

• Rheumatology
• Nephrology
• Immunology

Background:

• Sjögren's syndrome is a chronic autoimmune disease primarily affecting exocrine glands.
• Hypocomplementemic urticarial vasculitis is a rare condition characterized by urticarial lesions and low complement levels.
• Renal involvement is a known complication of Sjögren's syndrome.

Observation:

• A 46-year-old female with Sjögren's syndrome presented with ascites, lymphadenopathy, angioedema, and urticarial skin lesions.
• Biopsy confirmed Sjögren's syndrome (stage IV) and laboratory tests revealed low C1q and high C1q antibodies.
• The patient later developed lower limb edema, proteinuria, and was diagnosed with membranous nephropathy.

Findings:

• The patient exhibited a rare presentation of Sjögren's syndrome with hypocomplementemic urticarial vasculitis and angioedema.
• Low C1q levels and high C1q antibodies indicated complement system activation.
• Renal biopsy confirmed membranous nephropathy, a significant complication.

Implications:

• This case highlights the complex and varied clinical manifestations of Sjögren's syndrome.
• Early recognition and management of vasculitis and renal complications are crucial for favorable outcomes.
• Understanding the immunological pathways involved may inform future therapeutic strategies for Sjögren's syndrome and its complications.