Surveillance of oral cultures for Enterobacteriaceae during bone marrow transplantation

Bone marrow-transplanted patients can suffer from severe life-threatening infections. Oral bacterial cultures were collected from a group of 40 patients prior to and following bone marrow transplantation every 3 days, following initial preparation and eradication of oral infections. The samples were grown on the Titertek-Enterobac kit specific for Enterobacteriaceae. In 426 oral cultures 30.5% grew gram-negative bacteria, 76.6% of them were Enterobacteriaceae, Young male patients had 8.3% positive cultures at the study start, a percentage which constantly increased during later periods. Older patients did not follow the same pattern. Also, the allogeneic transplantation group had a higher percentage of Enterobacteriaceae than the autologous group (49.0 versus 19.5%). In blood cultures 18 out of the 94 positive ones showed the presence of Enterobacteriaceae. The most commonly found microorganisms in oral cultures were Klebsiella oxytoca (23%), Enterobacter cloacae (18%) and Klebsiella pneumoniae (15%). The decrease in the positive oral cultures from 35.0% during the pretransplantation period to 5.4% close to the transplantation, demonstrates that the preparatory protocol used for the prevention of oral infections was highly effective.