[Clinical characteristics and related factors of rheumatoid arthritis complicated with tuberculosis infection]

To investigate the clinical characteristics and high risk factors of Rheumatoid arthritis (RA) complicated with tuberculosis infection.

Patients with rheumatoid arthritis diagnosed in the hospital of Sichuan Provincial People's Hospital from January 2007 to January 2017 was retrospectively collected, who were enrolled in the study group. A control group was randomly selected from the RA patients hospitalized in the same period without co-infection at a ratio of 1 :2. The general data, clinical data, laboratory test data, treatment plan, etc. of the two groups were collected in detail for single factor statistical analysis. Then multivariate Logistic regression was used to analyze the independent risk factors of RA complicated with tuberculosis infection with statistical significance in univariate analysis.

The clinical manifestations of fever (83.3%) were most common, followed by cough (69%) and body mass loss (45.2%). In the infected group, pulmonary tuberculosis accounted for 73.3%. In the infected group the chest CT showed two or more cases, accounting for 59%. There were 9 cases (33.3%) occurring in the typical tuberculosis occurrence site. Compared with the control group, the erythrocyte sedimentation rate (ESR), C-reaction protein (CRP) levels, and the daily average dose of glucocorticoid in 1 year in the infected group were higher than those in the control group. And those differences were statistically significant(P < 0.05). There were no significant differences in gender, age, disease duration, disease activity score, white blood cell (WBC), platelet (PLT), hemoglobin (Hb), immunoglobulin G (IgG), complement (C), Anti cyclic citrullinated peptide antibody (anti-CCP), CD4⁺T cell count, and immunosuppressant use (P > 0.05). Multivariate Logistic regression analysis showed that CRP levels(OR=1.016, 95%CI:1.002-1.031) and the daily average dose of glucocorticoid in 1 year(OR=1.229, 95%CI:1.066-1.418)were the independent risk factors of RA complica-ted with tuberculosis infection.

RA patients with tuberculosis infection are mainly phthisis. The clinical manifestations of RA combined with tuberculosis infection are lack of specificity, and the chest imaging features of pulmonary tuberculosis are diverse, which are easy to be misdiagnosed. CRP levels and the daily average dose level of glucocorticoid in 1 year were risk factors for RA and tuberculosis infection.