{
  "abstract": "Objectives Systemic lupus erythematosus (SLE) is a chronic autoimmune connective tissue disease closely associated with the presence of antinuclear antibodies (ANA). Once ANA positivity has been confirmed, repeated testing generally provides limited additional clinical information. The objective of this study was to assess the current practices of ANA test requests among patients with SLE at our hospital center.Methods We conducted a retrospective review of all ANA test requests processed at the Clinical Pathology laboratory of our center between 2022 and 2024. Patients who met the 2019 EULAR/ACR classification criteria for SLE and had continuous follow-up throughout the study period were included. For each patient, demographic, clinical, and laboratory data were collected. Each repeated ANA request was analyzed in relation to concurrent clinical manifestations and the emergence of new antibody specificities.Results A cohort of 30 patients was included, comprising 26 females (86.7%) and 4 males (13.3%), with a mean age of 51.2 years (range: 27–81). The mean disease duration was 11.9 years (range: 2–37). A total of 138 ANA test requests were identified, corresponding to a mean of 4.6 requests per patient (range: 2–14). Internists ordered 99 tests (71.7%) and nephrologists ordered 20 (14.5%).The most frequently observed ANA patterns were AC-4,5,31 nuclear speckled (n=56) and AC-1 nuclear homogeneous (n=51), whereas other patterns were considerably less represented.During follow-up, changes in ANA patterns were detected in 16 tests (11.6%). ANA patterns remained stable in 19 patients (63.3%). The most frequent transitions involved AC-1 to AC-4,5,31 and AC-8,9,10. Among patients showing a change in ANA pattern, 5 (45.5%) presented new clinical manifestations, and 3 (27.3%) exhibited changes in antibody specificity.Conclusions Frequent retesting of ANA in patients with SLE demonstrated limited clinical utility. These findings underscore the importance of optimizing testing practices by reinforcing the use of ANA primarily as a diagnostic rather than a monitoring tool. Enhancing clinical judgment and fostering effective communication with pathologists are crucial to ensure appropriate contextual interpretation of results, prevent unnecessary testing, and ultimately promote more cost-effective healthcare practices.",
  "authors": [
    {
      "affiliations": [
        "Unidade Local de Saúde Braga, Braga, Portugal"
      ],
      "name": "Sílvia Santos"
    },
    {
      "affiliations": [
        "Unidade Local de Saúde Braga, Braga, Portugal"
      ],
      "name": "Juliana Almeida"
    }
  ],
  "title": "PO:02:034 Antinuclear antibodies in systemic lupus erythematosus: are we over-testing?",
  "uid": "052a0c85-1fb9-5fd3-9225-5cd3b26cd978"
}