Is selective digestive decontamination useful in controlling aerobic gram-negative bacilli producing extended spectrum beta-lactamases?

AIMS: To identify outbreak episodes of either carriage or infection due to extended spectrum beta-lactamases producing aerobic Gram-negative bacilli (AGNB-ESBL); to establish whether AGNB-ESBL, sensitive to tobramycin, become resistant over time; and to evaluate the impact of selective decontamination of the digestive tract (SDD) on abnormal carriage of AGNB-ESBL. DESIGN AND SETTING: All children admitted to the pediatric intensive care unit (PICU) over a 12-month period had biweekly surveillance cultures of throat and rectum and diagnostic cultures when clinically indicated. All AGNB were tested for ESBL, and the positive isolates were sent for molecular typing. The PICU uses SDD (parenteral cefotaxime and enteral polymyxin E/tobramycin) to control abnormal carriage. Patients who had at least one AGNB-ESBL were included in the study. RESULTS: During the study period, 1,101 children were admitted to the PICU. There were 39 patients (3.5%) with a total of 236 cultures positive for AGNB-ESBL. Twenty-eight patients (2.5%) were carriers, and 11 (1%) had proven infections. Organisms isolated from the first culture were 14 patients with Klebsiella pneumoniae, 8 with Enterobacter cloacae, 7 with Citrobacter freundii, 5 with Klebsiella oxytoca, and 5 with Escherichia coli. In the first sample, 59% of isolates showed tobramycin resistance. Molecular typing confirmed that there were five different strains of K. pneumoniae and that similar strains were not isolated in the same period. CONCLUSIONS: SDD is an effective measure to control AGNB-ESBL and to avoid outbreak episodes of either carriage or infection. When tobramycin resistance is found, replacing it with another aminoglycoside based on antibiogram may be more effective in achieving AGNB clearance.

Antibiotic-resistant bacteria and infection in children with cerebral palsy requiring mechanical ventilation.

INTRODUCTION: Severe and chronic illness can alter the bacterial flora carried in the oropharynx and gut. There are little data on the bacterial flora of children with chronic neurologic impairment. OBJECTIVES: To assess carriage of abnormal bacterial flora, antibiotic-resistant bacteria, infection, and mortality in children with cerebral palsy (CP) admitted for pediatric intensive care. DESIGN: Prospective observational single center cohort study. SETTING: Twenty-bed regional pediatric intensive care unit (PICU) in a university-affiliated tertiary referral children's hospital. PATIENTS: All children with an established diagnosis of CP admitted to PICU and ventilated for four or more days during a 6-yr period. MEASUREMENTS: Surveillance samples of throat and rectum were taken at admission to PICU and twice a week thereafter. Diagnostic samples were obtained on clinical indication. MAIN RESULTS: Fifty-three children with a total of 77 admissions were included. Most (90%) of the children with CP had moderate to severe functional limitations. Eighty-nine percent of the children with CP (47/53) carried abnormal bacterial flora/potential pathogens, most frequently Pseudomonas and Klebsiella species. Forty-seven percent (22/47) had antibiotic-resistant bacteria. Thirty-five children (66%) developed 86 infections during their PICU admission. Lower airways and blood were the two most commonly infected sites-Pseudomonas aeruginosa and coagulase-negative Staphylococci, the predominant infecting microorganisms. Sixty-five percent (56/86) of infections were primary endogenous infections, 21% (18/86) exogenous, and 9% (8/86) secondary endogenous. Carriage of abnormal bacterial flora, antibiotic-resistant bacteria, and infection rate was significantly higher than that of children of comparative age without CP ventilated for four or more days on PICU. Nine (17%) of the children with CP died in PICU and 4 of the deaths were infection related. CONCLUSIONS: In children with moderate to severe chronic neurologic impairment admitted to PICU, there is a high rate of carriage of abnormal bacteria/potential pathogens, antibiotic-resistant bacteria, and infection.