Age-wise Distribution of Antinuclear Antibody (ANA) Patterns by Indirect Immunofluorescence Assay (IFA): A Cross-Sectional Study at a Tertiary Care Hospital in Central India

Abstract

Background: Antinuclear antibody (ANA) testing using indirect immunofluorescence assay (IFA) plays a pivotal role in the early diagnosis and classification of autoimmune disorders. Age-related variations in ANA patterns have been observed, influencing clinical interpretations and subsequent management.

Objective: This study aimed to investigate the distribution of ANA patterns among various age groups in patients from a tertiary care center in Central India, utilizing the IFA technique on HEp-2 cells.

Methods: A cross-sectional observational study was conducted at SAIMS Medical College and PG Institute, Indore, from January 1, 2025, to May 15, 2025. ANA-positive serum samples (n=211) were analyzed. The fluorescent patterns were categorized according to the International Consensus on ANA Patterns (ICAP) and stratified by age groups: 0–20, 21–40, 41–60, and over 60 years.

Results: The most frequent pattern was nucleoplasm speckled (30.3%), followed by cytoplasmic homogenous (25.6%). The 21–60 years age groups demonstrated the highest pattern diversity. Rare patterns like few nuclear dots and cell nucleoli peripheral were seen in isolated cases.

Conclusion: There is a notable age-dependent variation in ANA patterns. Recognizing these patterns can improve diagnostic precision and guide further clinical investigation.