DOI: http://dx.doi.org/10.18203/2320-6012.ijrms20160524

Ease with VITEK 2 systems, biomerieux in identification of non-lactose fermenting bacteria including their antibiotic drug susceptibility: our experience

Susmitha Simgamsetty, Padmaja Yarlagadda, Bindu Madhav Yenigalla, Ramesh Babu Myneni

Abstract


Background: Nonfermenters are being isolated from various clinical specimens. Although frequently considered as contaminants, the pathogenic potential has been proved beyond doubt by their frequent isolation from clinical material and their association with disease. In the recent years due to the liberal and empirical use of antibiotics, Non Fermenting Gram Negative Bacilli (NFGNB) have emerged as important health care associated pathogens. Several automated systems are available for the identification and susceptibility of the clinically important bacteria. In this study we have evaluated the ease of the VITEK-2 Compact in identifying the NFGNB along with its antibiotic sensitivity.

Methods: A total of 186 strains which grew in culture from various clinical specimens isolated at the Clinical Microbiology Laboratory, NRI General Hospital, Chinakakani, Guntur District, A.P. during the period from January 2015 to June 2015 were included in the study. The Vitek-2 Compact machine was validated using the standard strains as per the manufacturer’s instructions. The isolates were processed as per the Manufacturer’s instructions for Identification and Antimicrobial Sensitivity Testing (AST).

Results: Out of the 186 strains, 50 strains were isolated from tracheal aspirate, 47 from pus/wound infections, 43 from blood cultures, 25 from urine, 20 from sputum and one from central line tip. The VITEK-2 compact system identified all the strains with a level of 95-99% probability. Most of the strains were identified as Pseudomonas aeruginosa followed by Acientobacter baumannii. Pseudomonas aeruginosa strains were most susceptible to Meropenem (72%) and least susceptible to Cefuroxime and Trimethoprim/Sulfamethoxazole (0%) while Sphingomonas paucimobilis showed resistance to all the antibiotics tested.

Conclusions: Care in detection, evaluation of effective antibiotic options, and judicious use of antibiotics by instituting antibiotic policy for combination therapy and rigorous infection control measures will help us to fight against these multidrug resistant NFGNB during the effective management of patients.

 


Keywords


NFGNB, VITEK-2 Compact, Drug resistance, Identification

Full Text:

PDF

References


Gokale SK, Metgud SC. Characterization and antibiotic sensitivity pattern of nonfermenting gram negative bacilli from various clinical samples in a teritiary care hospital, BELGAUM-JPBMS. 2012;17(14).

Aliga L, Mediavilla JD, Cobo F. A clinical index predicting mortality with pseudomonas aeruginosa bacteremia. J Med Microbiol. 2002;51(7):615-9.

Rit K, Nag F, Raj HJ, Maity PK. Prevalence and susceptibility profiles of Nonfermentative Gram-negative Bacilli infection in a Tertiary care Hospital of Eastern India. Indian Journal of Clinical practice. 2013;24(5).

Patel PH. Prevalence of non-fermenting gram negative bacilli infection in tertiary care Hospital in Ahmedabad, Gujarat. Indian journal of Basic Applied Medical Research. 2013;2(6):608-13.

Kirthilaxmi K, Benachinmardi. Prevalence of nonfermenting Gram negative bacilli and their in vitro susceptibility pattern at a teritiary care teaching Hospital. Journal of scientific society. 2014;41(3).

Bergogne - Berezin E, Towner KJ. Acinetobacer spp as Nosocomial pathogens: Microbiological, Clinical and Epidemiological features. Clin Microbial Rev. 1996;9(2):148-65.

Stager CE, Davis JR. Automated Systems for identification of microorganisms. Clin Microbiolol. 1992:302-27.

David H. Pincus Biomerieux, inc Hazelwood, Mo, USA; Microbial identification using the Biomerieux VITEK- 2 System.

Joyanes P, del Carmen Conejo M, Martinez-Martinez L, Perea EJ. Evaluation of the VITEK 2 system for the identification and susceptibility testing of three species of nonfermenting gram-negative rods frequently isolated from clinical samples. J Clin Microbiol. 2001;39:3247-53.

Biomeriux VITEK-2 Compact ref Manual – Ref-414532.

National Committee for Clinical Laboratory Standards. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically. Approved Standard M7 A5. Normal committee for clinical laboratory standards. Wayne, Pa. 2000.

Bruno D, Nishano MK, Prior WN, Remus PR, Do Cormo AA. Prevalence of Gram negative nonfermenters Patients in proto Alegre – RS. Journal Brasileiro de Patologia e Medina Laboratorial. 2011;47:529-34.

Funke G, Monnet D, deBernardis C, von Graevenitz A, Freney J Evaluation of the VITEK 2 system for rapid identification of medically relevant gram-negative rods. J Clin Microbiol. 1998;36:1948-52.

Taneja N, Maharwal S, Sharma M. Imipenem resistance in nonfermenters causing nosocomial urinary tract infections. Indian J Med Sci. 2003;57(7):294-9.

Kumari HB, Nagaratna S, Chandramukhi A. Antimicrobial resistance pattern among aerobic gram negative bacilli of lower respiratory tract specimens of intensive care unit patients in a neuro centre. Indian J Chest Dis Allied Sci. 2007;49(1):19-22.

Gilardi GL. Antimicrobial susceptibility as a diagnostic aid in the identification of nonfermenting gram negative bacteria. Appl Microbial. 1971;22(5):821-3.

Von Gravenitz A. Clinical Microbiology of unusual pseudomonas species. Prog Clin pathol. 1973;5:185-218.