Bacteraemia during the aplastic phase after allogeneic bone marrow transplantation is associated with early death from invasive fungal infection

Abstract

Episodes of bacteraemia during the aplastic phase were studied in 500 allogeneic bone marrow (BMT) recipients, regarding incidence, microbial aetiology, risk factors, mortality and causes of death. One hundred and sixty-four patients (33%) had at least one positive blood culture. Gram-positive cocci (α-streptococci and coagulase-negative staphylococci) were found in 146/164 cases (89%). Gram-negative bacteria were present in only seven cases. Receiving marrow from an unrelated donor was the only significant risk factor for bacteraemia in univariate regression analysis. Within 60 days after BMT, 69/500 patients died. The mortality rate was significantly higher among those with positive blood cultures during the aplastic phase, 44/164 (27%) than in those without bacteraemia, 25/336 (7%). Death directly caused by sepsis was unusual in patients with α-streptococci or CNS-bacteraemia (8/146, 5%). In contrast, three of seven patients with gram-negative bacteraemia died of the infection. However, in patients with bacteraemia, 21 of 44 deaths were attributable to invasive fungal infections (18 candida, three aspergillus; autopsy findings). Among patients with negative blood cultures during the aplastic phase, 6/25 died of invasive fungal infection (three candida, one saccaromyces and two aspergillus). This indicates that early bacteraemia is associated with death from invasive fungal infection. Therefore, efforts to shorten the neutropenic period after BMT, prevention, early detection of invasive fungal infections and adjustments of immnosuppressive regimens when marrow from an unrelated donor is used, may improve the outcome after BMT.