HANDOC - a handy score to determine the need for echocardiography in non-beta-hemolytic streptococcal bacteremia

Background: Non-beta-hemolytic streptococci (NBHS) are a common cause of infective endocarditis (IE). Echocardiography is used to diagnose IE, but it is not known which patients with NBHS bacteremia should undergo echocardiography.

Method: Medical records of patients with NBHS bacteremia in southern Sweden from 2012-2014 were studied retrospectively. The patients were divided into two cohorts. In the first, correlations between the reported data and IE were studied. These variables were used to construct the HANDOC score, which was then validated in the second cohort.

Results: 340 patients with NBHS bacteremia were included in the first cohort of whom 26 fulfilled the criteria for IE, and in 197 cases IE could be excluded. Several factors differed significantly between the patients with IE and those without. Amongst these variables, the presence of Heart murmur or valve disease, Aetiology with the groups of S. mutans, S. bovis, S. sanguinis or S. anginosus, Number of positive blood cultures ≥2, Duration of symptoms of 7 days or more, Only one species growing in blood cultures, and Community acquired infection were chosen to form the HANDOC score. With a cut-off between two and three points, HANDOC had a sensitivity of 100% and specificity of 73% in the first cohort. When tested in the validation cohort (n=399), the sensitivity was 100% and the specificity 76%.

Conclusion: HANDOC can be used in clinical decision making to identify patients with NBHS bacteremia who have a risk of IE so low that echocardiography can be omitted, therefore implementation might reduce the use of echocardiography.