Outcome of bacteremia and fungemia in paediatric oncology patients

OBJECTIVE:

To determine the outcome of paediatric oncology patients with positive blood cultures.

DESIGN:

Retrospective chart review.

SETTING:

Tertiary care hospital.

POPULATION STUDIED:

Oncology patients up to 17 years of age with positive blood cultures from January 1, 1994 to March 31, 1999.

MAIN RESULTS:

There were 121 episodes of positive blood cultures in 76 patients. Seventeen episodes were excluded because blood cultures were contaminated. Of the organisms grown from the remaining episodes, 63% were Gram-positive organisms, 23% were Gram-negative organisms, 3% were fungal and 11% were mixed. There were 13 episodes with pure or mixed isolates of Staphylococcus aureus, of which nine occurred within 14 days of the placement of a new central venous tunnelled catheter. Central venous tunnelled catheters were retained in 76 of the 102 episodes when they were present. There were two relapses, and four children were admitted to the intensive care unit with septic shock, but all survived.

CONCLUSIONS:

The outcome was excellent with the current management of possible bacteremia in paediatric oncology patients, but the high incidence of S aureus bacteremia suggests that empirical antibiotics should be altered if sepsis is suspected within 14 days of the placement of a central venous catheter.Key Words: Bacteremia, Empirical antibiotics, Fungemia, Oncology, PaediatricBacteremia and fungemia are common causes of morbidity in paediatric oncology patients. Mucositis of the gastrointestinal tract undoubtedly results in increased opportunities for bacteremia to occur. Impaired host defenses and the seeding of indwelling venous lines increase the chance that this bacteremia will be continuous rather than transient. Bacteremia also occurs following breaks in sterile technique during the manipulation of venous lines. The pathogenesis of fungemia in this patient population is not well delineated, but one likely source is from venous catheters being infected following transient fungemia from gut flora.It is standard practice to start empirical antibiotics in all febrile oncology patients who are neutropenic. The empirical antibiotic regimen used in paediatric oncology patients in our centre is tobramycin and piperacillin. Most non-neutropenic febrile oncology patients are also admitted and started on these same antibiotics, because there is evidence that their incidence of bacteremia may be at least as frequent as that of neutropenic patients (1). In our centre, venous catheters are removed in the face of suspected line infection only if the venous catheters are nontunnelled, permanent venous access is no longer required, the infecting organism is a yeast, bacteremia persists after several days of appropriate antibiotics or the patient has septic shock that is thought to be line-related. The purpose of the present study was to evaluate the outcome of patients by using this approach to suspected bacteremia or fungemia.