Bacteriological Assessment of Pneumonia Caused by Gram-Negative Bacteria in Patients Hospitalized in Intensive Care Unit

Abstract

The article presents the results of 11-year study (2005-2015) of Gram-negative bacteria responsible for pneumonia in 2033 mechanically ventilated patients hospitalized in Intensive Care Unit. Of 8796 biological samples, consisting mainly of bronchial aspirate (97.9 %), 2056 bacterial strains were isolated and subjected to identification. VITEK 2 was used to determine drug susceptibility (classified according to the EUCAST criteria). ESBL, MBL and KPC-producing strains were identified by means of phenotypic methods using appropriate discs. The findings were that the predominant bacteria responsible for infections consisted of Enterobacteriaceae (42.0 %), Acinetobacter baumannii (37.2 %), Pseudomonas aeruginosa (16.1 %), and Stenotrophomonas maltophila (4.7 %). We observed a rise in the number of bacteria causing pneumonia throughout the study period, especially in S. maltophila and Enterobacteriaceae ESBL (+). Gram-negative bacilli were 100 % susceptible to colistin, apart from naturally resistant strains such as Proteus mirabilis, Serratia marcescens, whereas Enterobacteriaceae ESBL (+) were susceptible to imipenem and meropenem. Acinetobacter baumannii strains exhibited the lowest drug susceptibility. In conclusion, we report an increase in the prevalence of pneumonia associated with Gram-negative bacteria in mechanically ventilated intensive care patients. Colistin remains the most effective drug against the majority of Gram-negative bacteria. Therapeutic problems are common in the course of treatment of Acinetobacter baumannii infections.

The respiratory threat posed by multidrug resistant Gram‐negative bacteria

“…Several recent studies have reported an elevated prevalence of GNB in nosocomial pneumonia, ranging from 25% in Poland up to 85% in Europe and in the US (Table ). Different microorganisms have been described as the most frequent ones.…”

“…Other studies described a higher isolation of Enterobacteriaceae among patients with nosocomial pneumonia. Guzek et al . evaluated retrospectively more than 2000 patients with VAP and positive bacterial cultures in Poland and showed a high prevalence of Enterobacteriaceae (42%), with an incidence of ESBL of 26%.…”

“…Other studies described a higher isolation of Enterobacteriaceae among patients with nosocomial pneumonia. Guzek et al 41 evaluated retrospectively more than 2000 patients with VAP and positive bacterial cultures in Poland and showed a high prevalence of Enterobacteriaceae (42%), with an incidence of ESBL of 26%. In addition, Koulenti et al 42 described a prevalence of 51% for Enterobacteriaceae among 827 patients with HAP and VAP in a multicentre prospective study in Europe and Di Pasquale 47 showed that Enterobacteriaceae was responsible for 47% of ICU-acquired pneumonia in Spain.…”

Emergence of blaNDM-1 and blaVIM producing Gram-negative bacilli in ventilator-associated pneumonia at AMR Surveillance Regional Reference Laboratory in India

“…The etiology of VAP pathogens are changing over the past years, therefore early detection of pathogens and knowledge of sensitivity patterns are very crucial for better patient outcomes [ 5 ]. There is an increasing evidence of emergence of multidrug‑resistant (MDR) pathogens due to extended spectrum beta (β)-lactamases (ESBL), AmpC β-lactamases (AmpC) or metallo-β-lactamases (MBLs) [ 6 ].…”

Molecular Epidemiology of Multi-Drug Resistant Pseudomonas aeruginosa Isolates from Hospitalized Patients in Greece

“…In total, 34.15% of the CARB R isolates were characterized as VIM-2 producers which were identified exclusively from patients from Pneumology and ICUs in H2 (Table S1). The bacterium is known to colonize the lungs of patients with Cystic Fibrosis with highly resistant VIM-2 isolates [43], but it is also widespread in patients with other respiratory problems [44][45][46]. The isolation of MDR/VIM-2 strains from sputum and bronchial secretions during the present study was not surprising, although it was the first time that the P. aeruginosa population of H2 was tested for MBL production.…”