Clinical significance of group A streptococcal infection in pediatric patients with enthesitis related arthritis / 中华风湿病学杂志

ABSTRACT

Objective:To demonstrate the clinical significance of group A streptococcal infection (GAS) in patients with enthesitis related arthritis (ERA).Methods:A retrospective study was conducted on ERA (136) and PolyRF-/Oligo juvenile idiopathic arthritis (JIA) (272) patients in Beijing Children's Hospital from 2016 to 2018. Anti-streptococcal hemolysin "O" (ASO) was tested and documented in all patients. The infection rate of GAS was compared between patients with ERA and PolyRF-/Oligo JIA. Patients with ERA were divided to two groups according to the result of ASO (ASO positive and ASO negative). All the clinical data were documented and compared within the two groups. The statistical methods used mainly include t test, rank sum test, chi-square test, and Spearman correlation analysis.Results:The GAS infection rate of patients with ERA was higher than patients with PolyRF-/Oligo JIA (17.6% vs 9.5%, χ2=5.52, P=0.019). In ERA patients, clinical data were analyzed, and a statistical significant difference was observed in the presence of human leukocyte antigen (HLA)-B27 between ASO positive and ASO negative group [75.0%(18/24) vs 49.1%(55/112), χ2=5.329, P=0.021]. Statistical differences were found in Patrick's sign positive rate between the two groups [100%(24/24) vs 67.0%(75/112), χ2=10.61, P=0.001]. There was statistically significant difference between the two groups regarding the radiogr-aphic grading at the sacroiliac joint. More patients with positive ASO had grade Ⅲ damage at the sacroiliac joint compare to patients with negative ASO [68.2%(15/22) vs 28.4%(29/102), χ2=12.49, P<0.001]. The logarithmic of the ASO was slightly correlated with the radiographic grade of sacroiliac joint ( r=0.26, P=0.005). Conclusion:Patients with ERA are prone to be infected by GAS. It's probably related to HLA-B27 postivity for antigen presentation. Patients who were infected by GAS fre-quently have sacroiliac joint involvement, and tend to be more sever. This indicates that GAS may play an important role in the pathogenesis of sacroiliac joint destruction.