Anti-nuclear antibodies in patients with suspicion of neuromyelitis optica spectrum disorder: Frequency and significance

Abstract

Background & Objectives: Neuromyelitis Optica spectrum disorder (NMOSD) is an autoimmune inflammatory disease involving optic nerves and spinal cord. The association of NMOSD with anti-nuclear antibodies and autoimmune disorders has been reported. This study was conducted to determine frequency of anti-nuclear antibodies (ANA) in patients with NMOSD and to observe for the development of symptoms related to autoimmune disorders on follow up.

Methodology: After approval from Institutional Review Board, this cross-sectional study was conducted at Immunology Department, Shifa International Hospital, Islamabad, Pakistan and after informed verbal consent from patients, serum samples were tested by indirect immunofluorescence for anti-aquaporin four antibodies (AQP-4) and ANA. Clinical data of patient was collected via a structured questionnaire. Follow-up of 6-12 months was conducted in patients who were positive for ANA.

Results: Total 248 patients were included in this study of which 32 were positive for AQP4- Antibodies (mean age 32.4 ± 14.1 years), out of which ANA was positive in 17 (53%) patients whereas in AQP-4 negative group, ANA was positive in 70 (32%) patients. At one year follow-up, in AQP-4 and ANA positive group, two patients were diagnosed with autoimmune thyroid disorders and one patient was diagnosed with Systemic Lupus Erythematosus.

Conclusion: In this study, we concluded that ANA were observed more frequently with AQP-4 antibody positivity. Considering this, detection of ANA in AQP-4 antibody positive patients may help in establishing early diagnosis of an accompanying autoimmune disease leading to early diagnosis and an overall favorable outcome in patients.