What test patterns are seen on ANA immunofluorescence and what is their clinical significance?

• A. ANA patterns include homogeneous, speckled, nucleolar, and centromere; a speckled pattern is common in SLE and overlap syndromes; centromere pattern suggests limited scleroderma.
• B. ANA patterns are not clinically informative.
• C. A homogeneous pattern is specific for Sjögren syndrome.
• D. A centromere pattern indicates rheumatoid arthritis.

Answer: (A)

ANA immunofluorescence patterns reflect the autoantibody specificities and help point toward certain connective tissue diseases. A homogeneous (diffuse) pattern is associated with anti-dsDNA antibodies and is classically seen in systemic lupus erythematosus. A speckled pattern is common and broad, reflecting antibodies such as Sm, RNP, SSA/Ro, and SSB/La, and it’s often seen in SLE and overlap syndromes. A nucleolar pattern suggests involvement of systemic sclerosis–related antibodies targeting nucleolar antigens. A centromere pattern strongly indicates limited cutaneous systemic sclerosis (the CREST variant). Thus, recognizing these patterns and their disease associations explains why the described pattern set and its clinical significance are correct.