129: Gastric Flora in Gastrostomy Fed Children with Neurological Impairment on Acid Suppression Medication

Aspiration pneumonia (AP) is the most common cause of hospitalization and death in children with neurologic impairment (CNI). Yet, very little is known about the conditions that contribute to AP in CNI or how it should be treated. Furthermore, it is unclear if current routine interventions in CNI, including G-tubes and acid suppression medication (ASM), have altered previously held assumptions about the microbiological causes of AP in these children. (1) To describe the type, concentration and susceptibility profile of bacteria found in gastric aspirates of CNI with G-tubes; (2) to compare gastric flora of CNI in ambulatory settings to those admitted to hospital with AP; and (3) to explore predictors of bacterial colonization of the stomach. We recruited CNI who were G-tube fed and on regular ASM. Outpatients were recruited from routine clinic visits at a children's hospital in Canada; inpatients were admitted with a clinical diagnosis of AP. Excluded were immunocompromised patients and those on 24/7 home ventilation. Gastric aspirates were collected from the G-tube and sent for pH and microbial testing. All pathogenic bacteria were tested for antibiotic sensitivity. 42 patients (21 inpatients, 21 outpatients) have been recruited to date. Omeprazole was the most common ASM (N=38). Among inpatients, 50% had an underlying genetic syndrome, mean pH of gastric sample was 5.6±2.2 and mean bacterial growth was 2.17×108 CFU/mL. Among outpatients, 65% had an underlying diagnosis of cerebral palsy, mean gastric pH was 5.4±1.8 and mean bacterial growth was 2.85×108 CFU/mL. All inpatient and outpatient samples collected with pH2 (n=38) showed growth, with Streptococcus viridans (22.7%), Klebsiella pneumoniae (10.8%) and Pseudomonas aeruginosa (8.9%) being the most common organisms grown. There was no significant difference in the types of organisms found in gastric samples of inpatients vs. outpatients. Antibiotic sensitivity rates assessed in pathogenic bacteria were 96.6%, 96.6%, 93.5% for ciprofloxacin, gentamycin and tobramycin, respectively. Traditionally considered a sterile environment, a variety of microorganisms, many of which are common flora of the oropharyngeal tract, are being found in gastric aspirates of study participants. This may be related to increases in gastric pH secondary to ASM. Further studies will be needed to correlate organisms grown in gastric aspirates of CNIs on ASM to those causing APs as this may have implications for the optimal treatment of APs in this patient population.