Background:

Pediatric oncology patients are at a higher risk of developing febrile neutropenia. Likewise an advanced age ≥65 years is one of the predictors of the development of neutropenic fever in adult oncology patients. We hypothesized that pediatric patients have higher rate of febrile neutropenia and bacteremia compared to adult patients. Hence, in this study we aimed to compare and analyze the incidence and type of bacteremia in pediatric and adult oncology patients during febrile neutropenic episodes.

Methods:

We retrospectively extracted medical records of hospitalized patients between January 2006 and January 2012 with a diagnosis of malignancy including leukemia and neutropenic fever at Hurley Medical Center using ICD‐9 codes. Pediatric patients were ≤ 18 years of age and adult patients’ ≥ 19 years of age. The Chi‐square, independent t‐test and One‐way ANOVA with LSD post hoc were used for statistical analysis.

Results:

Of a total of 251 patients who met the criteria, 178 (71%) were pediatric patients, while 73 (29%) were adults. Mean WBC count was 930 ± 1580 with a range of 0 to 19,800 and median of 500. Absolute neutrophil count ranged from 0 to 1372 with a mean of 230.9 ± 330.3 and median of 68. In our pediatric age group, 87% (155/178) had severe neutropenia (≤ 500/µL) compared to 75.3% (55/73) of adult patients (p<0.022). Mean length of stay was 7.7 ± 5.9 days for pediatric patients and 12.6 ± 9.3 days for adult patients (p<0.001). Fifty‐two percent (38/73) of adult patients had positive blood culture, while in pediatric patients, 15.7% (28/178) had positive blood cultures (p<0.001). There were a total of 73 organisms isolated, with 38% from pediatric (28/73) and 62% (45/73) from adult patients. Six patients had more than one organism in the blood culture. Pediatric patients had 54% (15/28) gram negative and 46% (13/28) gram positive, while adult patients had 56% (25/45) gram positive, 40% (18/45) gram negative and 4% (2/45) fungal isolates. In pediatric patients with positive blood cultures, 25% (7/28) had E coli, 10.7% (3/28) had Klebsiella, 7.1 % (2/28) had pseudomonas and 3.6% (1/28) had MRSA. In adult patients, 8.9 % (4/45) had MRSA, 8.9% (4/45) had E. coli, 8.9% (4/45) had Klebsiella, and 4.4% (2/45) had pseudomonas. A higher proportion of E.coli in positive blood cultures from 2006 to 2008 (25.7%) was found compared to 2009 to 2012 (6.7%) p=0.047. Forty‐nine percent (36/73) of adult patients had hematologic malignancy, while 81.5% (145/178) of pediatric patients had the same (p<0.001). Eighty‐seven percent (155/178) of pediatric patients had internal (port) catheter at the time of febrile neutropenia compared to 47% (34/73) in adult patients (p<0.001).

We found a positive correlation between age and WBC (r = 0.134, p<0.033) and between age and ANC (r = 0.255, p<0.001).During the period between 2006 and 2008, 81.1% of neutropenic oncology patients admitted to the hospital were pediatric compared to 18.9% of adults, while during the period between 2009 and 2012, 59.7% were pediatric compared to 40.3% adults who got admitted (p<0.001).

Conclusions:

We found that although our pediatric patients had more severe neutropenia and a higher percentage of patients had internal venous catheters (both risk factors for bacteremia), our adults had higher incidence of bacteremia. Severe neutropenia could be related to higher prevalence of hematologic malignancies in pediatric patients. Gram negative organisms were more prevalent in pediatric patients, while gram positives were more prevalent in adults.