Comparing Resistant Microorganisms Isolated from Patients and Environment in an Intensive Care Unit

Background: Recently, the probable involvement of surfaces from the hospital environment as a disseminating source of resistant bacteria has been highlighted. The aim of the study was to compare resistant microorganisms isolated from inanimate surfaces, equipments and patient blood culture samples in an Intensive Care Unit from Belo Horizonte, Brazil. Methods: A cross-sectional study was performed from July to October 2009. Data sources were microbiologic samples from environment and patient blood culture. Duplicate samples were obtained by swabs from up to seven different touch sites around two different patients in four different days. Jointly with the environmental samples, bacterial isolates from an adult ICU patients’ routine blood cultures were obtained from hospital laboratory. The samples were identified, tested for sensitivity and compared by rep-PCR test to verify similarity. Results: Difference among the averages of Colony Forming Units was found within the environment samples (p < 0.004). In the environment were identified antibiotic resistant microorganisms such as Vancomycin resistant Enterococcus faecalis, imipenem and ciprofloxacin Pseudomonas aeruginosa and multidrug-resistant Acinetobacter baumannii. Similarities (60% -80%) were established among environmental and blood culture samples. Conclusion: The environmental sampling showed different averages of contamination of the surfaces and equipment. The similarity among the bacterial isolates of patients’ blood cultures and environmental samples reinforces the hypothesis of the horizontal transference of pathogens.

Epidemiological Characteristics, Resistance Patterns and Spread of Gram-Negative Bacteria Related to Colonization of Patients in Intensive Care Units

Our aim was to determine the epidemiological characteristics, the resistance patterns and the spread of Gram negative bacteria related to colonization of patients in adult Intensive Care Units. Methods: A prospective cohort of patients colonized and/or infected with Gram negative bacteria was conducted at two adult ICUs from hospitals in Brazil (April 2012 to February 2013). Nasal, groin and perineum swabs were performed. Samples were incubated on MacConkey and cetrimide agar (48 h at 37℃) and identification tests (Vitek-BioMérieux), antibiogram (Bauer-Kirby method), Carba NP test, Polymerase Chain Reaction (PCR) and sequencing were performed. The patterns of resistant microorganisms were compared by rep-PCR (Diversilab). Results: There were 53 cases of colonization. In these cases, we identified imipenem-resistant Acinetobacter baumannii (51%), Pseudomonas aeruginosa (32%), Klebsiella pneumoniae ESBL (38%) or imipenem resistant (5.6%). The use of antimicrobials and medical devices were related to colonization (p The resistance patterns expressed by Klebsiella pneumoniae were ESBL (CTX-M, SHV e TEM) and KPC2. A verified profile of Acinetobacter baumannii was related to OXA-23 and OXA-253 (OXA-143 variant). The profiles ESBL and KPC2 expressed by Klebsiella pneumoniae were distributed between the both ICUs. The distribution of OXA-23 and OXA-253 was verified only in one ICU. The similarity of strains ranged from 80% to 95%, highlighting the horizontal transference of these microorganisms.