›› 2012, Vol. 32 ›› Issue (11): 1482-.doi: 10.3969/j.issn.1674-8115.2012.11.018

• Original article (Clinical research) • Previous Articles     Next Articles

Clinical features of infective endocarditis with positive antineutrophil cytoplasmic antibodies

YAO Dong-ting1, YANG Cheng-de2, DING Hui-hua2, YING Chun-mei1   

  1. 1.Department of Clinical Laboratory, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200127, China;2.Department of Rheumatology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200001, China
  • Online:2012-11-28 Published:2012-11-30

Abstract:

Objective To investigate the clinical features of infective endocarditis (IE) with positive or negative antineutrophil cytoplasmic antibodies (ANCA). Methods Thirty-nine patients with IE were were divided into ANCA positive group and ANCA negative group according to the serum ANCA findings by ELISA. The clinical features of patients such as general conditions, susceptible factors, clinical manifestations, laboratory indexes and involved valves were retrospectively analysed, and the parameters were compared between two groups. Results ANCA was positive in 13 of the 39 patients (33.3%), and all were PR3-ANCA positive. Native valve endocarditis was diagnosed in 37 patients, and organic heart disease was present in 34 of them, while no basic heart disease was found in the other 3 patients. There was no significant difference in the prevalence of susceptible factors between ANCA-positive group and ANCA-negative group (P>0.05). The major clinical manifestations of patients included anemia (66.7%), splenomegaly (38.5%), nephropathy (28.2%), arthralgia (23.1%) and edema of lower extremity (17.9%). The prevalence of edema of lower extremity in ANCApositive group was significantly higher than that in ANCA-negative group (38.5% vs 7.7%)(P<0.05). As for laboratory findings, higher C-reactive protein (CRP) values were found in all the patients, higher erythrocyte sedimentation rate (ESR) occurred in 89.7% patients, while lower concentration of haemoglobin (Hb) was detected in 66.6% patients. Besides, 50.0% patients had hematuria, and 53.8% patients had proteinuria. However, there was no significant difference in all the laboratory indexes between two groups (P>0.05). Blood cultures were performed in 37 patients, and a causative microorganism was identified in 15 (40.5%) patients. The positive rate of blood culture in ANCA-positive group was significantly higher than that in ANCA-negative group (69.2% vs 25.0%)(P<0.05). Seventeen strains of pathogenic bacteria were isolated, among which 14 were Streptococcus. Three patients in ANCA-positive group died, among whom 2 were misdiagnosed as ANCA associated small vessel vasculitis (AAV). There was no case of death in ANCA-negative group. Conclusion There may exist cases of ANCA-positive IE, which may be misdiagnosed as AAV. ANCA-positive IE may be attached great importance in clinics.

Key words: antineutrophil cytoplasmic antibodies, infective endocarditis, vasculitis