Original Article

Anaerobic infections in patients admitted in various surgical units of a tertiary care hospital of north India: neglected but important

Abstract

Background and Objectives: Anaerobic infections are usually caused by the host’s endogenous flora due to a breach in the anatomical barriers and Bacteroides spp. are the most notorious organisms associated with anaerobic infections. The identification of anaerobes has been a challenge since times. MALDI-TOF-MS is a boon for aiding the rapid detection of anaerobic organisms and has helped us to enlist the distribution of various anaerobic pathogens.
Materials and Methods: This retrospective analysis (January 2018 to December 2019) was carried out in a tertiary care hospital in North India, in which the anaerobic microbiological profile of all patients admitted to surgical wards, ICU, and OPD of various departments (Orthopedics, Surgery, Gynecology, and Obstetrics) was reviewed. Samples received were immediately processed aerobically (5% sheep blood agar and Mac Conkeyagar) as well as anaerobically (RCM and freshly prepared sheep blood agar) as per the laboratory protocols.
Results: Bacteroides fragilis (19.12%) was the most common anaerobe whereas among aerobes Escherichia coli (30.2%) followed by Klebsiella pneumoniae (10.34%) were most commonly isolated. The majority of patients were males (56%) and the most common presentation was with abscesses (21.4%). Polymicrobial infections (69.51%) outnumbered monomicrobial ones (30.48%).
Conclusion: There is a paucity of literature on anaerobe isolation from surgical infections from our country which motivated us to study anaerobic infections and the high sample size in our institute enabled us to study surgical infections from an anaerobic perspective. This will add to the knowledge of microbiologists and clinicians. MALDI-TOF MS helped in rapid and accurate identification and hence we could report a wider spectrum of organisms in our study.

1. Murphy EC FI. Gram-positive anaerobic cocci - commensals and opportunistic pathogens. FEMS Microbiol Rev 2013; 37:520-553.
2. Shenoy PA, Vishwanath S, Gawda A, Shetty S, Anegundi R, Varma M, et al. Anaerobic bacteria in clinical specimens – frequent, but a neglected lot: A five year experience at a tertiary care hospital. J Clin Diagn Res 2017; 11:DC44-DC48.
3. Cohen-Poradosu R KD (2015). Anaerobic Infections: General concepts. In: Bennet JE, Dolin R, Blaser MJ Eds. Mandell, Douglas and Bennett’s Principles and Practice of Infectious Diseases. 8th ed. Elsevier health(Saunders). Philadelphia: US, pp. 2736-2743.
4. Edmiston CE, Krepel CJ, Seabrook GR, Jochimsen WG. Anaerobic infections in the surgical patient: microbial etiology and therapy. Clin Infect Dis 2002; 35(Suppl 1):S112-118.
5. Senne JE, McCarthy LR. Evaluation of a metronidazole disk test for the presumptive identification of anaerobes. Am J Med Technol 1982; 48:613-616.
6. Mandell GL, Bennett JE, Dolin R E (2005). Mandell, Douglas, and Bennett’s Principles and practice of infectious diseases. 6th ed. Elsevier health (Saunders). Philadelphia: US. pp. 3083-3089.
7. Japanese Society of Chemotherapy Committee on guidelines for treatment of anaerobic infections; Japanese Association for Anaerobic Infections Research. Chapter 1-1. Anaerobic infections (General): epidemiology of anaerobic infections. J Infect Chemother 2011; 17 Suppl 1:4-12.
8. Antony B, Justin S, Raveendran R, Shetty AK, Kuruvilla TS, Boloor R. Spectrum of anaerobes encountered in surgical infections in a tertiary care hospital in Mangalore, coastal Karnataka: A prospective study. Muller J Med Sci Res 2016; 7:40-43.
9. Ananth-shenoy P, Vishwanath S, Targain R, Shetty S, Rodrigues GS, Chiranjay Mukhopadhyay C, et al. Anaerobic infections in surgical wards: a two year study. Iran J Microbiol 2016; 8:181-186.
10. Kaur S, Rajagopalan S, Kaur N, Shafiq N, Bhalla A, Pandhi P, et al. Drug utilization study in medical emergency unit of a tertiary care hospital in north India. Emerg Med Int 2014; 2014:973578.
11. Brook I. Bacteroides infections in children. J Med Microbiol 1995; 43:92-98.
12. Park Y, Choi JY, Yong D, Lee K, Kim JM. Clinical features and prognostic factors of anaerobic infections: a 7-year retrospective study. Korean J Intern Med 2009; 24:13-18.
13. Boyanova L, Kolarov R, Mitov I. Recent evolution of antibiotic resistance in the anaerobes as compared to previous decades. Anaerobe 2015; 31:4-10.
14. Wren MWD. The culture of clinical specimens for anaerobic bacteria: A comparison of three regimens. J Med Microbiol 1977; 10:195-201.
15. Saini S, Gupta N, Aparna, Lokveer, Griwan MS. Surgical infections: a microbiological study. Braz J Infect Dis 2004; 8:118-125.
16. Summanen PH, Talan DA, Strong C, McTeague M, Bennion R, Thompson JE, et al. Bacteriology of skin and soft-tissue infections: comparison of infections in intravenous drug users and individuals with no history of intravenous drug use. Clin Infect Dis 1995; 20 Suppl 2:S279-282.
17. Sethi S, Shukla R, Bala K, Gautam V, Angrup A, Ray P. Emerging metronidazole resistance in Bacteroides spp. and its association with the nim gene: a study from North India. J Glob Antimicrob Resist 2019; 16:210-214.
18. Brazier JS, Stubbs SL DB. Metronidazole resistance among clinical isolates belonging to the Bacteroides fragilis group: Time to be concerned? J Antimicrob Chemother 1999; 44:580-581.
19. Choudhry R, Mathur P, Dhawan B KL. Emergence of metronidazole resistant Bacteroides fragilis, India. Emerg Infect Dis 2001; 7:485-486.
20. Kirchner M, Mafura M, Hunt T, Card R, Anjum MF. Antibiotic resistance gene profiling of faecal and oral anaerobes collected during an antibiotic challenge trial. Anaerobe 2013; 23:20-22.
21. Wexler HM. Bacteroides: the good, the bad, and the nitty-gritty. Clin Microbiol Rev 2007; 20:593-561.
22. Salyers AA, Gupta AWY. Human intestinal bacteria as reservoirs for antibiotic resistance genes. Trends
Microbiol 2004; 12:412-416.
23. Shoemaker NB, Wang GRSA. Evidence for natural transfer of a tetracycline resistance gene between bacteria from the human colon and bacteria from the bovine rumen. Appl Environ Microbiol 1992; 58:1313-1320.
24. Shoemaker NB, Vlamakis H, Hayes K SA. Evidence for extensive resistance gene transfer among Bacteroides spp. and among Bacteroides and other genera in the human colon. Appl Environ Microbiol 2001; 67:561-568.
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IssueVol 13 No 3 (2021) QRcode
SectionOriginal Article(s)
DOI https://doi.org/10.18502/ijm.v13i3.6387
Keywords
Anaerobic bacteria; Metronidazole; Resistance; Bacteroides fragilis; Matrix assisted laser desorption/ionization- time of flight mass spectrometry; Oxidation-reduction potential

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How to Cite
1.
Singh C, Sood A, Bala K, Tandup C, Ray P, Angrup A. Anaerobic infections in patients admitted in various surgical units of a tertiary care hospital of north India: neglected but important. Iran J Microbiol. 2021;13(3):274-281.