Reasons for delayed diagnosis of ankylosing spondylitis in Chinese / 中华风湿病学杂志

ABSTRACT

Objective To investigate the reasons for delayed diagnosis of ankylosing spondylitis(AS) in a Chinese population.Methods Three hundred and eight patients fulfilled the 1984 Modified New York criteria of AS were enrolled.They were interviewed in person or by telephone by rheumatologists for 13 ques-tions.Results Of the 308 AS patients.238(75%)completed 13 questions.Among these 238 patients,male to female ratio was 6 to 1.The average age at AS onset was 22.1 years.Those aged under 15 years at disease onset Was 18.1%.and between 15 and 39 years was 79.0%while over 39 years was 2.9%.Of these 238 pa-tients.27(23.9%)had family history of AS.84.9% of the patients were HLA-B27 positive.The average dura-tion of delayed diagnosis in HLA-B27(+)and HLA-B27(-)were 70.1 and 88.1 months respectively,which was not significant statistically.Among those delayed over 10 vears,24 AS patients were HLA-B27(+)and 10 were HLA-B27(-),which was statistically significant(P=0.012).66.4% of 238 patients were misdiagnosed, of which 23.4%were diagnosed as arthritis associated with rheumatic fever,22.9% as fatigue and 20.3%as inter-vertebrate disc.45.0%were misdiagnosed by one physician while 2 1.4%were misdiagnosed for several times,and the average length of delay diagnosis was 72±68 months.Seven cases,although the diagnosisi was being delaved for more than 10 years the initial diagnosis was correct. Conclusion Delayed diagnosis of AS is common in China.The major reasons for delayed diagnosis are HLA-B27 negative and lack of X-ray changes of sacroiliac joint at the initial visit.