Avaliação da microbiota e perfil de citocinas extracelulares de pacientes com infecções intra-abdominais

Abstract

Intra-abdominal infections (IAI) include a diverse set of diseases whose complications lead to high morbidity and mortality, especially in intensive care units. These processes are most frequently polymicrobial, involving aerobic and anaerobic bacteria. However, an accurate microbiological diagnosis is not usually achieved. The aim of this study was to investigate the composition of IAI microbiota and its antimicrobial susceptibility profiles, including the anaerobic bacteria, and analyze the production of extracellular cytokines in the affected patients. Clinical specimens were obtained from patients seen in four health institutions in Belo Horizonte. Microorganisms were identified by the Vitek 2 bioMérieux System and Gram negative anaerobes were also subjected to polymerase chain reaction (PCR) and DNA sequencing, in confirmatory character. The minimum inhibitory concentration was determined by the agar dilution method for anaerobes and by the Vitek 2 for facultative bacteria. In the evaluation of extended spectrum -Lactamases (ESBL) producing the cefinase disks were used. The presence of the cytokines IL- 1, IL- 6, IL -8 and IL -10 and TNF was verified in serum and secretions of patients with IIA by flow cytometry using the BD - CBA Human Inflammatory Cytokines. Of the 51 patients evaluated, 34 were already using some antimicrobials at the time of collection. Microorganisms were recovered from 33 of 51 patients, anaerobic bacteria were present in 39.4 % (13 /33) of the positive specimens, with a predominance of the Bacteroides fragilis group. Phenotypic identification was confirmed by PCR in 14 (93.3%) of 15 samples of anaerobic BGN. Penicillin resistance was observed in 80.0% of anaerobes, of which 86.7 % were ESBL positive, 25.0 % were resistant to clindamycin and 12.5 % to cefoxitin. Half of the Enterobacteriaceae was resistant to five or more antibiotics of different classes, and 80.0 % of A. baumannii strains were resistant to imipenem. There was 81.8% of Staphylococcus spp. methicillin-resistant and all Enterococcus spp. strains to clindamycin. One sample of E. faecium was also resistant to vancomycin. The levels of cytokines, except for IL-10 were higher in the site of infection (IIA) than in the serum of patients. The hospital origin of the IIA and positive microbial culture were the only factors that influenced the level of cytokine production. Our data supports the need to study the prevalence and antimicrobial susceptibility profile in cases of IIA, taking into account the great diversity of microorganisms recovered and profile multidrug resistance part of them, especially among those involved in IIA of hospital origin.