Increased incidence of bacteraemia due to viridans streptococci in an unselected population of patients with acute myeloid leukaemia.

The aetiology, clinical characteristics and outcome of bacteraemia in patients with acute myeloid leukaemia were studied. All positive blood cultures collected at a haematological ward during 2 7-y periods were evaluated. Altogether, 274 episodes of bacteraemia in 152 patients were recorded, 80 episodes during 1980-86 and 194 during 1990-96. During the 2 periods, trimethoprim-sulfamethoxazol in combination with amikacin was the first-line empirical therapy in patients with neutropaenia and fever. In 1990, antimicrobial prophylaxis with ciprofloxacin and fluconazole was introduced. The incidence of bacteraemia due to viridans streptococci or coagulase-negative staphylococci increased from the first period to the second, whereas the incidence of Enterobacteriaceae decreased. In granulocytopaenic patients during 1990-96, viridans streptococci accounted for 21% of the isolates and in patients treated prophylactically with fluoroquinolone, viridans streptococci accounted for 31%. All viridans streptococci were sensitive to penicillin. At the time of the positive blood cultures, the patients of the second period were granulocytopaenic in 83% of the episodes. The mortality related to septicaemia during the later period was 13% and only 1 of 33 (3%) of the patients with viridans streptococci died. Eight patients (9%) died in relation to septicaemia following curative antileukaemic therapy.