MONITORAMENTO DE AEROCONTAMINAÇÃO POR ASPERGILLUS SPP. EM HOSPITAL TERCIÁRIO DE CAMPO GRANDE

Abstract

Aspergillus species are fungi that produce spores that are dispersed in the ambient air. Inhalation of these particles can lead from an allergic process, or a primary pulmonary infection until disseminated infection, commonly fatal in immunosuppressed patients. Aspergillus are responsible for the second highest occurrence of invasive fungal infections in tertiary hospitals. The objective of this study was to investigate aerocontamination by Aspergillus in conditioning air and indoor air of a tertiary hospital in Campo Grande- MS and to determine the antifungal susceptibility profile of the isolates. In the year 2021 air samples were collected at the Medical Clinic Unit (UCM), Intensive/Semi- Intensive Care Unit (UCIS), Urgent, and Emergency Unit (UUE) using an air sampler (volume of 100L/min for 1min) containing dichloran rose bengal agar plates. The plates were incubated for 72 h at 30°C. Aspergillus were identified at section level through their macro and microscopic characteristics and confirmed by PCR and DNA sequencing. Resistance to the antifungals itraconazole, voriconazole and posaconazole was determined by screening test as recommended by EUCAST, and resistance was confirmed with the broth microdilution methodology (EUCAST E.Def. 9.3.2). During one year of sampling total of 238 air samples were collected (ambient air= 184 and conditioning air=54). About 4.300 fungal colonies were isolated. Among these, 324 of Aspergillus spp. Through the phenotypic characteristics, the isolates were identified at the section level being 29.5% from the Fumigati section, 27.4% from the Nigri section, 22.5% from the Versicolores section, 11.7% from the Flavi section, 5.2 % from Nidulantes section, 3.1% from Terrei section, and in 0.6% it was not possible to identify the section. Aspergillus from de Fumigati section were more isolated in the winter and in the UCIS. The azole antifungal screening test was performed in 148/324 isolates. Of these, the broth microdilution test was performed with 16 (10.8%) isolates to confirm resistance. Four (12.5%) isolated from the A. fumigatus, 2 (3.7%) from the A. flavus, two (3.7%) from the Nigri, being one (1.85%) A. tubingensis and 8 (32%) from the Versicolores section, being five (20.0%) A. sydowii, which showed resistance to at least one antifungal. In the conditioning air and indoor air of hospital units, where critical patients are found, were isolated fungi of the Aspergillus genus that can cause invasive aspergillosis. Aspergillus fumigatus resistant on the ambient air may favor aspergillosis of difficult treatment. Air monitoring of hospital units with critical patients is essential as a subsidy for implementing improvements in hospital air quality minimizing the acquisition of pulmonary and invasive aspergillosis.