Table 3.

Immunological manifestations and useful autoantibodies in the patients with chronic hepatitis C virus infection

Clinical symptoms	Useful autoantibodies	Differential diagnosis
Polyarthritis/polyarthralgia	RF, anti-CCP	RA
Sicca (dry eye/dry mouth)	Anti-SSA/SSB	SS
Purpura	Cryoglobulin	Cryoglobulinemic vasculitis
Leg ulcer	ANCA, Cryoglobulin	Systemic vasculitis
Glomerulonephritis	ANCA, Anti-dsDNA	SLE, systemic vasculitis
Cytopenia	Anti-dsDNA	SLE
Hepatitis	Anti-SM, Anti-LKM1	Autoimmune hepatitis
Thrombosis	Anti-CL IgG/M	APS
Depression/fatigue	Anti-thyroglobulin, Anti-TPO	Autoimmune thyroiditis

RF: Rheumatoid factor; Anti-CCP: Anti-cyclic citrullinated peptide; ANCA: Anti-neutrophil cytoplasmic antibody; Anti-dsDNA: Anti-double strand DNA; Anti-SM: Anti-smooth muscle; Anti-LKM1: Anti-liver kidney microsomal type 1; Anti-CL: Anti-cardiolipin; Anti-TPO: Anti-thyroid peroxidase; RA: Rheumatoid arthritis; SS: Sjögren syndrome; SLE: Systemic lupus erythematosus; APS: Antiphospholipid antibody syndrome.