Infective endocarditis in New Zealand: data from the International Collaboration on Endocarditis Prospective Cohort Study.

Aims: The International Collaboration on Endocarditis Prospective Cohort Study (ICE-PCS) collected worldwide data on the presentation, management and outcome of infective endocarditis (IE). We present data from patients with endocarditis enrolled from New Zealand.
Methods: Patients who fulfilled the Duke criteria for definite or probable endocarditis were enrolled from five district health boards: Auckland, Counties Manukau, Waitemata, Capital and Coast, and Canterbury, between June 2000 and September 2005.
Results: There were 336 New Zealand patients enrolled in the ICE-PCS. Prosthetic valve endocarditis occurred in 31%. Underlying medical conditions were present in 28% of patients, but only 4% of patients had rheumatic heart disease. Forty patients (12%) had healthcare-associated endocarditis. Viridans streptococci were the most common cause of IE (32%), followed by Staphylococcus aureus (24%). Patients with S. aureus IE were more likely to present within a week of symptom onset than those with viridans streptococcus IE (OR 4.18, 95% CI 2.36-7.42). Surgery was performed in 33% of patients. In total, 20 patients (6%) died in hospital. Those with endocarditis caused by coagulase-negative staphylococci had an increased risk of death compared with those viridans streptococcus endocarditis (RR 4.7, 95% CI 1.2-17). The risk of stroke was higher in those with endocarditis caused by S. aureus and coagulase-negative staphylococci (RR 2.7, 95% CI 1.2-6.05, and 4.9, 95% CI 1.9-13, respectively).
Conclusion: While viridans streptococci remain the predominant causative organisms of IE in New Zealand, many 'traditional' clinical and management aspects of this disease no longer apply. This paper provides a reference for local practitioners assessing and managing IE.