[Bacteremia in children with tumors or malignant diseases 1991-2000]

Ten to twelve children with tumors or malignant diseases are diagnosed annually in Iceland. Cancer treatment can cause severe immune suppression, which makes the patients susceptible to serious infections. The aim of the current study was to evaluate sepsis in children with tumors or haematological malignancies, describe the types of bacteria cultured and their antibiotic susceptibilities, and collect information on associated risk factors.

This was a retrospective study on all children 0-15 years of age in Iceland who were diagnosed with a tumor or malignant disease between 1991 and 2000. Information was gathered on diagnosis, treatment, blood cultures, blood tests, antibiotic use, presence of foreign bodies (such as CVC) and survival.

Hundred-and-eighteen children were diagnosed with cancer or benign central nervous system (CNS) tumors in Iceland during the period 1991-2000. Central nervous system tumors were most common (N=28, 23.7%), leukemia (N=21, 17.8%) and lymphoma (N=17, 14%) were the second and third. The mean age at diagnosis was 5.9 years. Sufficient data was found in the hospital records on 99 children who were included in the study. Five hundred and twenty two blood cultures were drawn from 51 of the 99 children during the period. The mean number of blood cultures per patient was 14.8 for children with leukemia, but 2.6 for children with solid tumors. Of all blood cultures, 63.6% were from a central venous catheter or a Port-A Catheter , 5% from a peripheral site, but 30% were undisclosed. Of the 522 blood cultures, 90 grew bacteria (17.2%). Coagulase-negative staphylococci were isolated from 53 blood cultures (60%) and Staphylococcus aureus from 12 (13%). Positive cultures were regarded as a definite or possible infection in 47 blood cultures (52%), contamination in 17 (18.9% ), but uncertain in 26 (27.7%). Over 60 percent of the blood cultures (N=302) were drawn when a child was neutropenic (ANC < or =1.0 *109/L). The mean length of neutropenic episodes was 9.0 days. The mean CRP level was 63.9 mg/L. The mean temperature was 38.8 degrees C. In 138 instances the child was receiving antibiotics at the time of culture (35.1%). Children with positive blood cultures had similar clinical and laboratory tests results as children with negative cultures.

Gram-positive bacteria, especially coagulase-negative staphylococci, are much more common in children undergoing cancer therapy than Gram-negative bacteria. Results of blood tests appear to have low predictive values for blood culture results. No child died of a proven bacterial sepsis during the study period. Empiric antibiotic treatment at the Children s Hospital Iceland for children with malignant diseases is still effective.