Turner syndrome complicating osteogenesis imperfecta, thyroiditis and ankylosing spondylitis: a case report

Abstract Background Turner syndrome (TS) is a chromosomal disorder characterized by monosomy of the X chromosome (45,X0) or structural aberrations in one of the X chromosomes in individuals with a female phenotype. Osteogenesis imperfecta (OI), commonly known as brittle bone disease, results from genetic abnormalities that lead to altered metabolism, reduced quantity, or structural defects in type I collagen, ultimately causing abnormal bone architecture, recurrent fractures, and progressive skeletal deformities. Case presentations We report a 27-year-old Chinese woman with TS (45,X0) and a history of osteoporosis and uveitis who presented with 11 years of low back pain and one month of bilateral ankle swelling. She had previously undergone spinal fixation and bilateral hip replacement. Examination revealed blue sclerae, height 132 cm, and weight 26 kg. Laboratory findings showed elevated erythrocyte sedimentation rate (ESR, 52 mm/hour) and C-reactive protein (CRP, 75.9 mg/L), positive HLA-B27, and elevated thyroid antibodies. Imaging revealed sacroiliitis on computed tomography and enthesitis on ankle magnetic resonance imaging (MRI). Genetic testing identified a heterozygous collagen type I α 1 chain (COL1A1) mutation and an Xp22.33-q28 deletion. She met the modified New York criteria for ankylosing spondylitis (AS). Treatment with adalimumab led to clinical improvement with decreased erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) after one month. Conclusions This case highlights the rare co-occurrence of TS, OI, and AS, emphasizing the importance of genetic and rheumatologic evaluation in complex presentations. We recommend annual clinical assessment for inflammatory back pain and, when clinically indicated, sacroiliac imaging (such as MRI or X-ray) to facilitate early diagnosis and management of concurrent rheumatologic conditions.