The aetiology and incidence of infective endocarditis in people living with rheumatic heart disease in tropical Australia

Eur J Clin Microbiol Infect Dis. 2023 Sep;42(9):1115-1123. doi: 10.1007/s10096-023-04641-6. Epub 2023 Jul 20.

Abstract

Purpose: To define the incidence and microbiological aetiology of infective endocarditis (IE) in patients with rheumatic heart disease (RHD) in tropical Australia.

Methods: A retrospective study that examined all episodes of IE between January 1998 and June 2021 among individuals on the RHD register in Far North Queensland, Australia.

Results: There were 1135 individuals with a diagnosis of RHD on the register during the study period, representing 10962 patient-years at risk. Overall, there were 18 episodes of definite IE occurring in 16 individuals, although only 7 episodes occurred in native valves (11 occurred in prosthetic valves) equating to 0.7 episodes of native valve IE/1000 patient-years. No patient with mild RHD - and only one child with RHD - developed IE during the study period. Despite the study's tropical location, the causative organism was usually typical skin or oral flora. Among individuals with an indication for benzathine penicillin G (BPG) prophylaxis, only 1/6 episodes of IE due to a penicillin-susceptible organism received BPG in the month before presentation.

Conclusion: Although RHD predisposes individuals to IE, the absolute risk of IE in native valve disease in tropical Australia is low and might be reduced further by improved adherence to secondary BPG prophylaxis.

Keywords: Bacterial sepsis; Dental health; Infective endocarditis; Rheumatic heart disease; Skin health; Tropical medicine.

MeSH terms

  • Australia / epidemiology
  • Child
  • Endocarditis* / epidemiology
  • Endocarditis, Bacterial* / diagnosis
  • Humans
  • Incidence
  • Penicillin G Benzathine / therapeutic use
  • Retrospective Studies
  • Rheumatic Heart Disease* / complications
  • Rheumatic Heart Disease* / drug therapy
  • Rheumatic Heart Disease* / epidemiology

Substances

  • Penicillin G Benzathine