Phenotypic characterization and susceptibility of gram negative bacteria from surgical site infections in a tertiary care hospital

Akhilesh P. S. Tomar, Anjali Kushwah


Background: Gram negative bacteria are the common isolates among the cases of Surgical Site Infections (SSI). Resistant and specially Multi Drug Resistant (MDR) Gram negative isolates are a serious challenge for the treatment to clinicians. Present study was undertaken for phenotypic characterization and susceptibility pattern of Gram negative bacterial isolates from cases of surgical site infections in a tertiary care institute.

Methods: This descriptive cross sectional hospital based study was conducted in a tertiary care teaching hospital over a period of one and half year from January 2012 to June 2013. Centers for disease control and prevention (CDC) SSI case definitions were used to label a case as SSI. Only culture proven cases, out of clinically suspected was included in the study for evaluation.

Results: During the study period a total of 5949 patients were operated and screened for SSI in the wards under surveillance. Out of which 556 were clinically suspected as a case of SSI. With 408 culture proven cases of SSI the rate of SSI in present study was (6.86%). Rates of SSI were more in dirty (22.54%) and contaminated (13.78%) type of wounds. Among Gram negative bacterial isolates (n=343) from SSI, E. coli (45.18%) was the commonest followed by Pseudomonas aeruginosa (16.03%) and Klebsiella pneumoniae (13.42%). Unpleasant trend in antimicrobial resistance observed during study is a serious concern.

Conclusions: The data presented in this study clearly indicate the continuous need of surveillance of SSI. This will clearly help health care personnel in curtailing down the incidences of SSI.


Klebsiella pneumoniae, Multi drug resiatant organism, Pseudomonas aeruginosa, Surgical site infections

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Burke JP. Infection control-a problem for patient safety. N Engl J Med. 2003;348:651-6.

World Health Organization. Report on the burden of endemic health care-associated infection worldwide: clean care is safer care. (WHO Document Production Services: Geneva, Switzerland, 2011).

Raka L. Prevention and control of hospital-related infections in low and middle-income countries. The Open Infectious Disease Journal. 2010;4:125-31.

Samuel, S et al. Nosocomial infections and the challenges of control in developing countries. Afr J Cln Exper microbial. 2010;11:102-10.

de Lissovoy G, Fraeman K, Hutchins V, Murphy D, Song D, Vaughn BB. Surgical site infection: incidence and impact on hospital utilization and treatment costs. Am J Infect Control. 2009 Jun 1;37(5):387-97.

World Health Organization. The evolving threat of antimicrobial resistance: options foraction. (WHO Library Cataloguing-in-Publication Data: Geneva, Switzerland, 2012).

Centre for Disease prevention and control. Types of health care-associated infections. (CDC 2012). Available at: types.html.

Yokoe DS, Anderson DJ, Berenholtz SM, Calfee DP, Dubberke ER, Ellingson KD, et al. A compendium of strategies to prevent healthcare-associated infections in acute care hospitals: 2014 updates. American journal of infection control. 2014 Aug 1;42(8):820-8.

Koneman EW, Allen S, Janda W, Schreckenberger P, Winn WC. Color Atlas and Text book of Diagnostic Microbiology, 6th Edn. New York: Lippincott; 2006.

Collee JG, Marmion BP, Fraser AG, Simmons A, Eds, Mackie & McCartney Practical Medical Microbiology, 14th Edition, Churchill Livingstone, New York, 11:245-258,4:151-177.

CLSI. Performance Standards for Antimicrobial Susceptibility Testing; Twentieth Informational Supplement. CLSI document M100-S20. Wayne, PA: Clinical and Laboratory Standards Institute; 2010.

Lilani SP, Jangle N, Chowdhary A, Daver GB. Surgical site infection in clean and clean-contaminated cases. Indian J of Med Microbiol. 2005;23:249-52.

National Nosocomial Infections Surveillance System. National Nosocomial Infections Surveillance (NNIS) System Report, data summary from January 1992-June 2001, issued August 2001. Am J Infect Control. 2001;29:404-21.

Tietjen L, Bossemeyer D, McIntosh N. Infection Prevention. Guidelines for Healthcare Facilities with Limited Resources. Baltimore, MD: JHPIEGO; 2003.

Weinstein R. Hospital-acquired infections. In: Kasper DL, Braunwald E, Fauci AS, Hauser SL, Longo DL, Jameson JL, Isselbacher KJ (eds.) Harrison's Principles of Internal Medicine. 16th Ed. New York: McGraw Hill; 2004.

Cheadle W. Risk factors for surgical site infection. Surg Infect (Larchmt). 2006;7:7-11.

Auerbach AD. Prevention of surgical site infections. In: Shojania KG, Duncan BW, McDonald KM, Wachter RM (eds). Making Health Care Safer A Critical Analysis of Patient Safety Practices. Evidence Report/Technology Assessment, No. 43. Rockville, MD: Agency for Healthcare Research and Quality; 2001.

National Noscomial Infections Surveillance. National Nosocomial Infections Surveillance (NNIS) System Report, data summary from January 1992 through June 2004, issued October 2004. Am J Infect Control. 2004;32:470-85.

Owens CD, Stoessel K. Surgical site infections: epidemiology, microbiology and prevention. J Hosp Infect. 2008;70:3-10.

Sikka R, Mann JK, Deep, Vashist MG, Chaudhary U, Deep A. Prevalence and Antibiotic Sensitivity Pattern of Bacteria Isolated from Nosocomial Infections in a Surgical Ward. Indian J of Clin Pract. 2012;22:519-25.

Raja NS, Singh NN. Antimicrobial susceptibility pattern of clinical isolates of Pseudomonas aeruginosa in tertiary care hospital. J Microbiol Imm Infect. 2007;40:45-9.

Weber SG, Miller RR, pereneevich EN, Tolentino J, Meltzer D, Pitrak D, et al. Prevalence of antimicrobial resistant bacteria isolated from older versus younger hospitalized adults: Results of a two centre study. J Antimicrob Chemother. 2009;64:1291-8.

Fadeyi A, Akanbi AA, Nwabuisi C, Onile BA. Antibiotic disc sensitivity pattern of Pseudomonas aeruginosa isolates obtained from clinical specimen in Ilorin, Nigeria. Afr J Med. 2005;34:303-6.

Gales AC, Jones RN, Turnidge J, Rennie R, Ramphal R. Characterization of Pseudomonas aeruginosa: occurrence rate, antimicrobial susceptibility pattern and molecular typing in the global sentry antimicrobial surveillance program 1997-1999. Clinic Infect Dis. 2001;32:146-55.

Van Eldere J. Multicentre surveillance of Pseudomonas aeruginosa susceptibility patterns in nosocomial infections. J Antimicrob Chemother. 2003;51:347-52.

Bradford PA. Extended-spectrum beta-lactamases in the 21st century: characterization, epidemiology, and detection of this important resistance threat. Clin. Microbiol. Rev. 2001;14:933-51.

Livermore DM. Woodford. The beta-lactamase threat in Enterobacteriaceae, Pseudomonas and Acinetobacter. Trends Microbiol. 2006;14:413-20.

Dhillon RH, Clark J. ESBLs: a clear and present danger?. Critical care research and practice. 2012;2012.

Thakuria B, Lahon K. The Beta Lactam Antibiotics as an Emperical Therapy in a Developing Country: An Update on Their Current Status and recommendations to Counter the Resistance against Them. J of Cli and Diag Resear. 2013;7:1207-14.

Gupta N, Limbago B, Patel JB, Kallen AJ. Carbapenem-Resistant Enterobacteriaceae: Epidemiology and Prevention. Clinical Infectious Disease. 2011;53:60-67.

Sievert DM, Ricks P, Edwards JR, Schneider A, Patel J, Srinivasan A, et al. Antimicrobial-resistant pathogens associated with healthcare-associated infections summary of data reported to the National Healthcare Safety Network at the Centers for Disease Control and Prevention, 2009-2010. Infection Control & Hospital Epidemiology. 2013 Jan;34(1):1-4.

Andrade SS, Jones RN, Gales AC, Sader HS. Increasing prevalence of antimicrobial resistance among Pseudomonas aeruginosa isolates in Latin American medical centres: 5 year report of the SENTRY Antimicrobial Surveillance Program (1997-2001). J Antimicrob Chemother. 2003;52:140-41.

Kallen AJ, Hidron AI, Patel J, Srinivasan A. Multidrug resistance among gram-negative pathogens that caused healthcare-associated infections reported to the National Healthcare Safety Network, 2006-2008. Infect Control Hosp Epidemiol. 2010;31:528-31.

Falagas ME, Koletsi PK, Bliziotis IA. The diversity of deļ¬nitions of multidrug-resistant (MDR) and pandrug-resistant (PDR) Acinetobacter baumannii and Pseudomonas aeruginosa. J Med Microbiol. 2006;55:1619-29.

Gould IM. The epidemiology of antibiotic resistance. Int J Antimicrob Agents. 2008;32:2-9.

Giske CG, Monnet DL, Cars O, Carmeli Y. Clinical and economic impact of common multidrug-resistant gram-negative bacilli. Antimicrobial agents and chemotherapy. 2008 Mar 1;52(3):813-21.