Background: Seronegative spondyloarthritis is characterized by the presence of subcutaneous nodules, asymmetrical peripheral arthritis, sacroileitis with or without spondylitis, and rheumatoid-factor negativity. Other common clinical manifestations include oral ulcers, conjunctivitis, and cutaneous lesions such as psoriasis. Familial aggregation has also been described. According to the 1986 classification, corresponding clinical entities include ankylosing spondylitis, psoriatic arthritis, Reiter’s syndrome, arthritis associated with inflammatory bowel disease (IBD), and undifferentiated spondyloarthritis. The disease is also frequently associated with the HLA B27 antigen. From the clinical point of view, there are often incomplete forms of spondyloarthritis, such as reactive arthritis triggered by asymptomatic infections, psoriatic arthritis without psoriasis itself, initial phases of specific forms of spondyloarthritis or the phase of ankylosing spondylitis characterized by sacroiliac lesions, and all forms that remain undifferentiated for long periods of time. Moreover, there are close relations between arthropathy and IBDs, such as Crohn’s disease, ulcerative colitis, and Whipple’s syndrome. Recently, microscopic inflammatory bowel lesions and psoriatic arthritis have been described. Case report: A 30-year-old man (HLA B27-negative) who had been vaccinated against TBC and HBV presented with a 6-year history of recurrent episodes of predominantly left-sided sciatica. The pain was worse at night and during rest. He was suffering from bilateral sacroileitis without spondylitis. Three to five times a day, usually after eating, he passed watery feces containing mucous and small amounts of bright red blood. Colonoscopy revealed pancolitis with histological evidence of chronic inflammation interspersed with areas of acute inflammation, edema, hyperemia, and glandular distortion. One year later, the clinical manifestations and histological findings were essentially unchanged: glandular distortions, chronic and acute inflammation of the lamina propria and crypt microabscesses. There were no granulomas and no evidence of uveitis. The inflammatory index was positive; FR, ENA, ANA titers were negative. He began therapy with adalimumab (loading dose 80 mg followed by 40 mg every 15 days) and mesalazine (2.4 g per os), and the clinical manifestations of the disease improved significantly.
Understanding the Pathogenesis of Spondyloarthritis