Abstract
Seronegative spondyloarthritis (SpA) are variably associated with HLA-B∗27 antigen. HLA-B∗27 negative SpA has also been reported from different parts of the world. There is paucity of data on this entity from Indian subcontinent. We studied 100 consecutively diagnosed HLA-B27 negative spondyloarthritis patients from a tertiary care center in India. Modified New York Criteria for ankylosing spondylitis (AS) and ESSG criteria for SpA were used for diagnosing patients. HLA-B∗27 typing was done by an in-house PCR-SSP technique in SpA patients to exclude B∗27 positive patients and PCR-SSOP technique was used to type 100 B∗27 negative SpA patients and 100 controls from the same ethnicity. Frequency of B∗07 was significantly increased (B∗07: % PF 54 versus 18; OR 5.348; 95% CI 2.808-10.186; P value 1.14E - 07), whereas frequency of B∗40 was significantly decreased (B∗40: % PF 17 versus 32; OR 0.435; 95% CI 0.222-0.850; P value 0.013) when compared with B∗27 negative controls. Among 100 SpA patients, 47 were undifferentiated spondyloarthritis and 33 patients were reactive arthritis patients. 40% of the patients were suffering from polyarticular arthritis, 35% had pauciarticular arthritis with knee joint, hip joint, ankle joint, and SI joint involvement. We conclude that B∗07 was significantly associated with B27 negative spondyloarthropathy from Western India and majority of B∗27 negative patients were uSpA.