Atlantoaxial synovitis as a rare presentation of post-gonococcal reactive arthritis

Abstract

BACKGROUNDReactive arthritis is a form of spondyloarthritis characterized by sterile synovitis induced by an extra-articular infection, usually of the genitourinary and/or gastrointestinal tract. The most common cause is Chlamydia trachomatis, but Neisseria gonorrhoeae and Ureaplasma urelyticum are also implicated. Axial involvement is frequent: half of the cases involve the lumbar spine, sacroiliitis is described in 15-30% and enthesitis in 30%. We will describe an unusual case of gonococcal-induced atlantoaxial synovitis. CASE REPORTFemale, 50 years old, previously healthy, hospitalized for 7 days of evolution characterized by excruciating neck pain, with stiffness and limited range of motion. Fourteen days ago, she treated profuse vaginal discharge with nitroimidazole. At no time she presented fever, urinary, gastrointestinal, ocular and/or cutaneous manifestations. Initial laboratory tests showed leukocytosis without deviation and increased acute phase reactants, both of which were rapidly increasing. Magnetic resonance imaging (MRI) showed synovitis in the lateral atlantoaxial joints and a thickening with enhancement in the capsuloligamentous structures. Due to the possibility of a reactional condition, but not being able to exclude an infectious process and considering the topography, oral corticosteroids and antibiotics were started concomitantly, with satisfactory results. Finally, PCR for N. gonorrhoeae in urine was positive, and HLA B27 was absent, with the remaining autoantibodies negative. CONCLUSIONThe occurrence of atlantoaxial synovitis can be considered a very rare presentation of postgonococcal reactive arthritis, probably one of the first reported cases. It is worth remembering that in the case above, the main differential diagnosis was gonococcal arthritis, but no manifestation of disseminated disease was present.