Potentially pathogenic bacteria isolated from neglected air and surfaces in hospitals

Hospital infections (HI) are a serious public health problem in many countries. Several studies have identified strains correlating to surgical site infections, many with multi-resistance. The goals of this study was to quantify, to identify and to verify the resistance profile of microorganisms collected at two hospitals settings, and to alert health professionals how environmental contamination can influence hospital infection rates. For air sampling in operating rooms, intensive care unit and materials sterilization center, the impaction method (Spin Air, IUL®) and passive sedimentation were used. For the isolation of bacteria on surfaces and uniforms contact plates (RODAC®) were used. Identification of the microorganisms was performed using Vitek® 2 Systems. The antibiograms were conducted according to the disk diffusion method recommended by CLSI. The surgical center of hospital B presented more than 500 CFU/m3 in aerial microbial load. In the aerial microbiota of the sampled areas of both hospitals, M. luteus, S. haemolyticus and S. hominis spp hominis were the prevalent microorganisms, with a percentage greater than 30%. On the surfaces and uniforms there was a prevalence of M. luteus (40%) and S. hominis spp hominis (20%) among others, and some of the resistant strains were isolated from environments with microbial load within the recommended limits.

Risks associated with pathogenic fungi isolated from surgical centers, intensive care units, and materials sterilization center in hospitals. Risks associated with pathogenic fungi isolated from critical hospital areas.

The hospital environment requires special attention to air quality, since it needs to be healthy for the protection of patients and health professionals in order to prevent them against hospital infections. The objective of this study was to isolate, identify and evaluate the susceptibility profile of isolated fungi from two hospitals. For air sampling the impaction (Spin Air, IUL®) and passive sedimentation methods were used. For the isolation of fungi from surfaces, contact plates (RODAC®) were used. The identification of the fungi was performed by observing the macroscopic and microscopic aspects of the colonies, whereas for better visualization of fruiting structures, the microculture technique was performed on slides. To evaluate the susceptibility profile, the broth microdilution test recommended by CLSI was performed. Thirty-five isolates were identified: Aspergillus flavus (12), Aspergillus fumigatus (11), Aspergillus niger (1), Aspergillus terreus (2), Penicillium spp. (7), and Fusarium spp. (2) in the hospitals evaluated. All isolates had a minimum inhibitory concentration (MIC) more than 128 µg/ml for fluconazole; 0.5 to 4.0 µg/ml for amphotericin B (hospital 1), and all isolates from haospital 2 had MIC ≥2.0 µg/ml. In hospital 1, MIC for posaconazole ranged from 0.25 µg/ml to ≥32 µg/ml, and hospital 2 ranged from 0.5 to 1.0 µg/ml. The monitoring and evaluation of air quality and surfaces are essential measures for prevention and control of hospital infections, as these microorganisms are becoming increasingly resistant to antimicrobial agents, thus making treatment difficult, especially in immunocompromised individuals.