Why is there an analytical culture in a medical laboratory?]

During a seven-year period (1998-94) 68 patients with infectious endocarditis were diagnosed at a university hospital. Staphylococcus aureus was the most common etiological agent (38%), followed by Streptococcus viridans (21%). In seven patients the diagnosis infectious endocarditis was first made during autopsy, all seven of them had the clinical diagnosis septicaemia. Surgery was performed on 41% of the patients. Case fatality was 34%. Case fatality was significantly higher for S aureus endocarditis than for S viridans endocarditis, 48% vs. 7% (p = 0.01). The advantages of transthoracic and transoesophageal echocardiography in the diagnosis and follow up of patients with infectious endocarditis is emphasized. In spite of these new diagnostic tools a definitive clinical diagnosis of infectious endocarditis was not made for 23% of the patients.