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The aim of this study was to characterize the practice of routinely obtaining tracheal aspirate cultures in children with tracheostomy tubes and to analyze the appropriateness of using this information to guide antibiotic selection for treatment of subsequent lower respiratory infections.Pediatric otolaryngologists and pulmonologists were surveyed regarding surveillance culture practices. Records of children with tracheostomy tubes from January 1, 2003, through December 31, 2007, were reviewed. Consecutive cultures were compared for similarity of bacteria and antibiotic sensitivity when a clinic culture preceded a culture from when the child was ill and received antibiotics and when a hospital culture preceded a hospital culture from a separate hospitalization.Seventy-nine of 146 pulmonologists and five of 33 otolaryngologists obtained routine surveillance tracheal aspirate cultures (P.001); 97% of pulmonologists used these cultures to guide subsequent empiric therapy. There were 36 of 170 children with one or more eligible pairs of cultures. Nearly all children had a change in flora in their tracheal cultures. Limiting empiric antibiotic choices to those that would cover microbes isolated in the previous culture likely would not have been effective in covering one or more microbes isolated in the second culture in 56% of pairs with the first culture from hospitalization vs 30% with the first culture from an outpatient setting (P = .15).This study demonstrated that there are significant changes in bacteria or antibiotic sensitivity between consecutive tracheal cultures in children with tracheostomy tubes. Use of prior tracheal cultures from these children was of limited value for choosing empiric antibiotic therapy in treating acute lower respiratory exacerbations. Surveillance cultures, thus, are an unnecessary burden and expense of care.

There is currently no approved vaccine against Pseudomonas aeruginosa, the major cause of morbidity and mortality in cystic fibrosis (CF) patients and a major pathogen in ventilated and burn patients. In a previous study, we demonstrated the immunization of mice with OprF(311-341)-OprI-type A- and B-flagellin fusion proteins dramatically enhanced clearance of nonmucoid P. aeruginosa. The goal of the current study was to evaluate the ability of OprF(311-341)-OprI-flagellins to elicit the production of protective IgG in young (4-6 months old) African green monkeys. Intramuscular immunization of African green monkeys with 1, 3, 10, or 30mug of OprF(311-341)-OprI-flagellins generated robust antigen-specific IgG responses. In addition, immunization with OprF(311-341)-OprI-flagellins elicited high-affinity anti-flagellins, OprI, and OprF IgG that individually promoted extensive deposition of complement component C3 on P. aeruginosa and synergized to facilitate maximal C3 deposition. Passive immunization of mice with plasma from OprF(311-341)-OprI-flagellins immunized monkeys significantly reduced lung bacterial burden three days post-challenge compared to mice that received pre-immunization plasma. Based on our results, OprF(311-341)-OprI-A- and B-flagellin fusion proteins are highly effective in mice and nonhuman primates and thus merit additional development as a potential vaccine for use in humans.