Beyond hepatitis C: clinical spectrum and demographic characteristics of anti-rods and rings antibodies in a large ANA-positive cohort.

BACKGROUND

The anti-rods and rings (anti-RR) pattern (AC-23) is traditionally associated with Hepatitis C Virus (HCV) infection and interferon therapy. However, emerging evidence suggests a broader clinical spectrum. This study aims to characterize the clinical associations, demographic shifts, and pattern complexity of anti-RR antibodies in a single-center retrospective study.

METHODS

A retrospective analysis was conducted on anti-RR-positive individuals identified from both the clinical cohort and the routine health checkup cohort. Clinical data, including disease categories, age, gender, concurrent ANA patterns, and antibody titers, were systematically evaluated.

RESULTS

Our findings demonstrate a heterogeneous clinical distribution of the anti-RR (AC-23) pattern across disease categories. Within the infectious disease group, hepatitis B virus (HBV) accounted for the largest proportion (36.59%), followed by hepatitis C virus (HCV) (24.39%), with a male predominance (M:F = 2.4:1, p<0.05). Among systemic autoimmune diseases, rheumatoid arthritis (RA) was the most frequently observed condition (25.64%), followed by connective tissue diseases (CTD) and autoimmune liver diseases (AIH/PBC). A distinct age- and sex-related distribution was observed, with higher frequencies in females aged 19-45 years, whereas a higher frequency was observed in males aged >65 years within the clinical cohort (p=0.045). Overall, anti-RR antibodies were predominantly detected at low titers (1:100-1:320). In addition, multiple immunofluorescence patterns, particularly speckled patterns, were more frequently observed in patients with autoimmune diseases, whereas isolated anti-RR patterns were more commonly identified in the routine health checkup cohort.

CONCLUSION

Anti-RR represents a distinct ANA pattern associated with a broad clinical spectrum in the Chinese population, extending significantly beyond HCV to include HBV infection and various non-infectious conditions. The diverse clinical associations and the predominance of low-to-moderate titers suggest that anti-RR should be interpreted as a general indicator of systemic immune involvement rather than a specific disease marker. Clinical management should prioritize comprehensive evaluation based on the individual's context rather than relying on anti-RR for specific disease screening.