STREPTOCOCCUS VIRIDANS BACTEREMIA FOLLOWING AUTOLOGOUS PERIPHERAL-BLOOD STEM-CELL TRANSPLANTATION

A retrospective evaluation of 200 consecutive recipients of autologous peripheral blood stem cell transplantation was conducted to ascertain the incidence and outcome of Streptococcus viridans bacteremia as wel l as to determine the role of prophylactic ampicillin therapy in the p eri-transplant setting, Viridans streptococci were isolated from the b lood of 35 individuals at a median of 6 days (range 2-8 days) followin g stem cell infusion, The most common isolates were S. sanguis and S. mitis. All patients received ciprofloxacin orally during the peritrans plant period, Additionally, 79 patients received oral ampicillin proph ylactically against gram-positive cocci, Although none of the patients suffered a fatal outcome, three individuals developed respiratory com promise requiring mechanical ventilation, Female sex proved to be the only independent risk factor for viridans streptococcal bacteremia (P= 0.04), The shorter duration of neutropenia observed after stem cell tr ansplantation did not impact on the incidence of S, viridans infection s, Moreover, the prophylactic use of ampicillin failed to decrease the incidence of viridans sepsis and selected out organisms that were res istant to betalactam antibiotics.