Aggregatibacter aphrophilus infective endocarditis confirmed by broad-range PCR diagnosis: A case report

Koji Hirano; Toshiya Tokui; Masahiro Inagaki; Taro Fujii; Yasumi Maze; Hirokazu Toyoshima

doi:10.1016/j.ijscr.2017.01.041

Aggregatibacter aphrophilus infective endocarditis confirmed by broad-range PCR diagnosis: A case report

Int J Surg Case Rep. 2017:31:150-153. doi: 10.1016/j.ijscr.2017.01.041. Epub 2017 Jan 19.

Authors

Koji Hirano¹, Toshiya Tokui², Masahiro Inagaki², Taro Fujii², Yasumi Maze², Hirokazu Toyoshima³

Affiliations

¹ Department of Thoracic and Cardiovascular Surgery, Japan Red Cross Ise Hospital, Ise, Japan. Electronic address: koji.hirano3@gmail.com.
² Department of Thoracic and Cardiovascular Surgery, Japan Red Cross Ise Hospital, Ise, Japan.
³ Department of Infectious Diseases, Japan Red Cross Ise Hospital, Ise, Japan.

Abstract

Introduction: Aggregatibacter aphrophilus is a rare cause of infective endocarditis. This pathogen is difficult to identify with common culture methods, which can lead to incorrect diagnosis and treatment.

Presentation of case: A 72-year-old woman was admitted to a community hospital with a persistent high fever and deteriorating renal function. Based on negative blood culture and positive serum proteinase 3 anti-neutrophil cytoplasmic antibody (PR3-ANCA), acute renal failure associated with ANCA-rerated vasculitis was initially suspected. However, the patient developed heart failure soon afterward; echocardiography showed mitral insufficiency with mobile vegetation attached to the mitral valve, indicating infective endocarditis. After transfer to our hospital, the patient underwent mitral valve repair. Broad-range polymerase chain reaction (br-PCR) and sequencing identified Aggregatibacter aphrophilus in the excised vegetation. The patient had a good postoperative course, with recovery of renal function.

Conclusion: A rare disease, Aggregatibacter aphrophilus infective endocarditis was successfully treated with surgical repair and appropriate antibiotic therapy. To avoid misdiagnosis, br-PCR testing should be performed in patients with blood culture-negative endocarditis.

Keywords: Aggregatibacter aphrophilus; Broad-range polymerase chain reaction; Case report; Culture-negative endocarditis; Infective endocarditis; Proteinase 3 anti-neutrophil cytoplasmic antibody.