Nosocomial colonization, septicemia, and Hickman/Broviac catheter-related infections in bone marrow transplant recipients - A 5-year prospective study

In this 5-year prospective study of 242 bone marrow transplantation (BMT) recipients from whom dally blood cultures via the indwelling Broviac/Hickman catheter were obtained, there was a median of 35 catheter- days during hospitalization, mean of 40 days, and total of 9,667 catheter- days which were divided almost equally between neutropenic (4,771) and non- neutropenic (4,896) days. One hundred twenty (50%) patients had a total of 161 episodes of nosocomial bacterial or candidal infections. Overall, 81 (33%) patients experienced 100 episodes of catheter-related infections and 90 (37%) patients experienced 112 episodes of septicemia, including 51 episodes of catheter-related septicemia. There was an incidence of 11.59 septicemia episodes, including 5.28 catheter-related septicemia episodes, 2.48 colonization only (without subsequent septicemia), and 2.59 exit site infections only, per 1,000 catheter-days. Over a period of a total of 6,593 afebrile days, 34 (14%) patients developed 40 episodes of colonization, a rate of 6.07 per 1,000 afebrile days, of which 16 developed into septicemia. Twenty-five patients had 1 episode each of exit site infection without bacteremia. There were 10 (4%) septicemia-related deaths, 4 of which were catheter-related; 50% of all deaths involved Pseudomonas aeruginosa. The mortality due to catheter-related septicemic episodes was not greater than that of the non-catheter-related episodes. Neutropenia was found to be a significant risk factor in our study: 76% of the septicemia episodes (85/112) and 65% of the catheter-related infectious episodes (65/100) occurred during neutropenia. There was a higher incidence of septicemic episodes during neutropenia than during non-neutropenic periods, 17.82 versus 5.51 per 1,000 days (p < 0.0001), and a higher rate of catheter-related infections during the neutropenic period, 13.62 versus 7.15 during non-neutropenic days per 1,000 days (p = 0.001). Fourteen of 16 colonization episodes developed into septicemia during neutropenia versus 2/24 during non-neutropenic periods, a rate of 5.47 versus 0.47 per 1,000 afebrile days, respectively (p < 0.0001), and 9/10 deaths occurred during neutropenia. Age ≤18 years (p = 0.003) and veno-occlusive disease (p = 0.028) were identified as risk factors for septicemia, but not for catheter-related infections, using Cox regression. The central venous catheter as a risk factor for septicemia could not be evaluated as it was present in all our study patients. Gram-negative isolates of both septicemia episodes and of catheter-related infections slightly exceeded the number of Gram-positive. The most frequent pathogens isolated were coagulase-negative staphylococcus, Escherichia coil, Klebsiella pneumoniae, P. aeruginosa, Streptococcus viridans and Enterococcus faecalis. Our findings indicate that nosocomial infections cause high morbidity with relatively low mortality during hospitalization for the BMT procedure. Based on the 6% incidence of our BMT recipients having had colonization which developed into septicemia during the neutropenic period, we suggest that it would be prudent for daily blood cultures via the central vein catheter be drawn during the neutropenic period, even on days when patients are afebrile, so as to enable early detection and treatment of pathogens causing colonization which may develop to septicemia.