N10. MDRO-GNR/emerging resistant bacterial pathogens
Oral Abstract Submission
Background : Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) were described first in relation to hospital acquired infections. However, infections by these organisms acquired in the community have become a public health problem. There are no well known risk factors for acquisition of these bacteria in the community. Surface waters and sanitation conditions may serve as reservoir and transmission.
We conducted a retrospective study over 12 months of patients who had positive cultures with ESBL-PE in our laboratory. We excluded patients with hospitalization in the previous 3 months, those in skilled nursing facilities, and those whose culture was taken 3 or more days after hospitalization. Geographic Information System analysis was performed based on patient’s residence, population and sewer overflow public data.
Among 485 patients with cultures positive for ESBL-PE in 2018, 64 were included in the study. Mean age was 54, and 68.7% were females. Organisms isolated were E.coli (78.2%) and K.pneumoniae ESBL (21.8%). These were isolated from urine 47 (73.4%), blood 5 (7.8%), abscess 6 (9.3%), ulcers 5 (7.8%), and sputum 1 (1.5%). Antibiotic exposure in the preceding 3 months was noted in 12 patients (18.7%). Spatial distribution of patients in the community was not random based on nearest neighbor analysis (Z score = -2.6). Kernel density estimation showed clustering of cases. Infection rates were calculated per census tracts. There was poor correlation between infection rate and mean family income (R2=0.18, p=0.017). Analysis of Kernel density estimations showed that sewer overflow distribution explained over 50% of the variance of distribution of cases with ESBL-PE (R2=0.51, p<0.001).
Conclusion : Patients presenting with infections due to ESBL-PE acquired in the community did not have a random spatial distribution. Other factors besides prior antibiotic use and financial status should be investigated. Proximity to sanitary sewer overflows may be a contributing factor. Location of residence within a community may aid in identifying patients at risk for acquisition of ESBL-PE.