Routine Surveillance for Bloodstream Infections in a Pediatric Hematopoietic Stem Cell Transplant (HSCT) Cohort: Do Patients Benefit?.

Background: HSCT recipients are at high risk of late bloodstream infection (BSI). Controversy exists regarding the benefit of surveillance blood cultures in this immunosuppressed population. Despite the common use of this practice, its practical value is not well established in non-neutropenic children following HSCT.

Methods: At the IWK Health Centre, a tertiary health care center serving 2.5 million in the three Maritime provinces of Canada, weekly surveillance blood cultures from central venous access lines (CVLs) are drawn from children following HSCT until CVL removal. We reviewed data from a prospectively collected CVL database in association with a health record review to determine the utility and cost of this practice. Eligible participants were non-neutropenic pediatric HSCT recipients with CVLs followed at the IWK between 1999 and 2005. Patients routinely received PCP and penicillin prophylaxis. Cultures were considered to be for surveillance if the child was afebrile without focus of infection. The cost of laboratory investigations, nursing time, hospital stay, and interventions for positive surveillance cultures was calculated.

Results: 43 HSCTs were performed in 41 patients of whom 21 were male (49%). The median age was 7 years (range 1–18). Donors were related in 15 cases (35%), unrelated in 18 (42%) and autologous in 10 cases (23%). The most common underlying illness leading to HSCT was leukemia (19/41; 46%) followed by solid tumour (7; 17%), inborn errors of metabolism and Fanconi Anemia (4 each; 10%) and other (4;10%). The median length of study eligibility, defined as the point at which the patient returned to the IWK from the transplant centre until the time of central line removal, was 70 days (range 7–176). There were 316 patient contacts for surveillance cultures (mean 7 per transplant) and 577 central line lumens sampled. Three patients had potentially clinically significant surveillance blood cultures that were positive (3/43; 7%). The bacteria isolated were Klebsiella pneumoniae (n=2) and Corynebacterium jeikium (n=1). Repeat cultures were done prior to initiation of antimicrobial therapy and all were sterile. Patients were admitted for antimicrobial therapy if they were not already hospitalized for HSCT care. Median hospitalization for treatment of the positive culture was 5 days. All three patients had an uncomplicated course. The estimated total cost of BSI surveillance and treatment of asymptomatic infection over 6 years was $27,989.

Conclusion: This study suggests that BSI surveillance in children post engraftment has a very low yield and significant cost. It is unclear that it contributes to improved patient outcomes.