Abstract
Background: To explore the infection characteristics of patients with rheumatoid arthritis(RA) and related risk factors for infection. Methods: A retrospective analysis of the clinical data of 648 hospitalized patients with RA, including related risk factors that may cause infection and infection sites, pathogens, and drug resistance. Chi-square test 、Mann-Whitney U test and binary Logistic-regression analysis were used to identify risk factors.Results: 648 patients with RA were 182 cases of infection, the infection rate 28.09%. Common infection were pneumonia(19.60%), urinary tract infection(5.25%), upper respiratory tract infection(5.09%). Gram-negative bacteria ranked first in the pathogen composition (67.57%), the main pathogenic bacteria were Pseudomonas aeruginosa and Escherichia coli; Staphylococcus aureus was the main pathogenic bacteria among the Gram-positive bacteria . In addition, there were 7 strains of fungi, 3 strains each of Mycobacterium tuberculosis and herpes virus. The proportion of resistant strains was relatively high, and the gram-negative bacteria had a relatively high sensitivity to penicillins/cephalosporins+β-lactamase inhibitors, aminoglycosides, and carbopenems. The risk scores included higher age (P=0.020), long disesses duration (P=0.004), smoking (P=0.016), hypoproteinemia (P=0.010), use of corticosteroids (P<0.01).Use of nonbiologic DMARDs was negatively with infection(P= 0.006).Conclusions: Our results indicate that the common infection sites in patients with RA are the respiratory and urinary tract. Gram-negative bacteria are common pathogens. RA patients with higher age, long diseases duration, smoking, hypoproteinemia, and long-term use of corticosteroids are prone to infection. Nonbiologic DMARDs is significantly associated with a decreased risk for infection. The proportion of drug-resistant patients with RA co-infection is relatively high.