RESUMO
BACKGROUND: Post cardiac surgery mediastinitis is the major infectious complication, despite the development of surgical techniques and the application of strict preventive measures. The Haemophilus influenzae mediastinitis is very rare. The mediastinitis caused by the association between Haemophilus influenzae and Aggregatibacter aphrophilus has never been described to our knowledge. CASE PRESENTATION: We report the case of an exceptional combination of Haemophilus influenzae and Aggregatibacter aphrophilus in a patient operated for single bypass which is complicated by mediastinitis the 10th day after the surgical act. CONCLUSION: The conclusion to be drawn from this work is to think in unusual seeds in case of mediastinitis post cardiac surgery for the elaboration of recommendations for antibiotic prophylaxis.