Diversity of metallo-b-lactamase-encoding genes found in distinct species of Acinetobacter isolated from the Brazilian Amazon Region

BACKGROUND The multidrug resistance (MDR) phenotype is frequently observed in Acinetobacter baumannii, the most clinically relevant pathogenic species of its genus; recently, other species belonging to the A. calcoaceticus-A. baumannii complex have emerged as important MDR nosocomial pathogens. OBJECTIVES The present study aimed to verify the occurrence of metallo-β-lactamase genes among distinct Acinetobacter species in a hospital located in the Brazilian Amazon Region. METHODS Antimicrobial susceptibility profiles were determined by broth microdilution. The genetic relationships among these isolates were assessed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Pyrosequencing reads of plasmids carrying the bla NDM-1 gene were generated using the Ion Torrent™ platform sequencing. FINDINGS A total of six isolates carried bla NDM-1: A. baumannii (n = 2), A. nosocomialis (n = 3), and A. pittii (n = 1); three carried bla IMP-1: A. baumannii, A. nosocomialis, and A. bereziniae. Resistance to colistin was observed for an NDM-1-producing A. nosocomialis isolate. Diverse PFGE patterns and sequence types were found among A. nosocomialis and A. baumannii isolates. The bla NDM-1 sequence was inserted in a Tn125 transposon, while the bla IMP-1 was found as a gene cassette of the class 1 integron In86. MAIN CONCLUSIONS To the best of our knowledge, this is the first report describing the dissemination of bla NDM-1 among distinct Acinetobacter species recovered from the same hospital in South America.

Antibiogram of Acinetobacter Species Isolated from Various Clinical Specimens in A Tertiary Care Hospital from North India.

Background: Acinetobacter species are most common pathogen to cause nosocomial infection, especially to the immune compromised patients or patients who are admitted in Hospital. These species causes UTI, Pulmonary infection, Septicaemia, Wound and soft tissue infection. Methods: In this study, total samples collected were 2404 in which 1700 were positive where as 289 were non-lactose fermenter & 1411 were lactose fermenter. Results: Total 89 Acinetobacter species isolated from various clinical specimens. Ampicillin/Sulbactum (91.0%), Ciprofloxacin (90.0%) & Ceftriaxone (89.0%) were more resistance & Colistin (72.0%), Meropenem (66.0%) were more sensitive. These species transmitted by patient contact, bedding, clothing, fomites, etc. Conclusion: Our study sugests that disinfectant & sterilization more important in routine.

Antimicrobial Resistance among Acinetobacter species and Evaluation of Risk Factors.

Background: Acinetobacter has gained importance as an emerging multi drug resistant nosocomial pathogen among non fermenting aerobic gram negative bacteria, especially in intensive care units. This organism is contributing to increased morbidity and mortality with strong propensity to colonize and disseminate among humans and environmental sources. Materials and Methods: A retrospective observational study was conducted from February 2013 to December 2013. Various clinical specimens received in microbiology laboratory from inpatients and outpatients were studied including their antimicrobial resistance pattern. A total of 111 Acinetobacter species isolates were included in the study. Associated risk factors were recorded from the clinical data which included demographic characteristics of the patient along with the indoor department, period of stay in ICU and hospital, presence of indwelling devices, antimicrobial therapy, surgical interventions, focal or generalized infections and underlying chronic morbid diseases. Results: In current study maximum number of Acinetobacter was from urine specimen (57.66%) followed by blood (25.23%). Among inpatients highest percentage of isolates was recovered from general surgical ward (26.88%) followed by intensive care units (24.73%). The number of MDR & XDR isolates recovered was 21(18.92%) & 11(10%) respectively. Imipenem, Meropenem and Doxycycline remained efficacious drugs against Acinetobacter infections with resistance rates of 18.02%, 30.63% and 36.94% respectively. The study revealed focal/generalized infections, indwelling devices, duration of stay in ICU & hospital, mechanical ventilation as significant risk factors in decreasing order for acquisition of MDR and XDR Acinetobacter but according to the statistical analysis only Diabetes mellitus was found to be significant (p value 0.019) whereas all other factors remained insignificant ( p value > 0.05). Conclusion: Prolonged usage of indwelling devices & medical equipments in critically ill patients along with longer duration of hospitalization can facilitate colonization and infection with Acinetobacter which is otherwise a low virulence pathogen. Strict compliance of disinfection policy and infection control programme with rational use of antibiotics especially carbapenems in Acinetobacter infections shall help in curtailing drug resistant strains from further dissemination.

Study of Acinetobacter Species with Special Reference to Carbapenem Resistance.

Bacteria of genus acinetobacter, invariably susceptible to many antibiotics earlier have emerged as a multidrug resistant opportunistic pathogen in recent years. Unwarranted and unrestricted usage of an antibiotic is associated with drug resistance in thereat in infections by acinetobacter species. Rapid detection of Metallo – Betalactamase starins can be done to prevent their dissemtination. The present study is undertaken to know antibiotic sensitivity pattern of acinetobacter species and screen the imipenem resistant starins for Metallo Beta Lactamase (MBL) production by various phenotypic methods.