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Year : 2014  |  Volume : 1  |  Issue : 3  |  Page : 31-33

Evaluation of in vitro sensitivity of Colistin to carbapenemase producing gram-negative bacilli

Department of Microbiology, Sri Aurobindo Institute of Medical Sciences, Indore, Madhya Pradesh, India

Date of Web Publication7-Aug-2014

Correspondence Address:
Gunjan Shrivastava
Department of Microbiology, Sri Aurobindo Institute of Medical Sciences Medical College, MR-10 Crossing, Indore-Ujjain Road, Indore - 453 555, Madhya Pradesh
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/2148-7731.138309

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Context: Increasing resistance in gram-negative bacteria presents a critical problem. Limited therapeutic option has forced infectious disease clinicians and microbiologists to reappraise the clinical application of Colistin. Aims: Emergency of resistance to multiple drugs leaves behind very few therapeutic options to fight out carbapenemase resistant gram-negative bacilli (GNB). Our objective was to study the in vitro sensitivity of Colistin to carbapenemase GNB. Settings and Design: This is the 6 months retrospective study. Materials and Methods: Present study was carried out in the Microbiology department in a tertiary care hospital and teaching institute, during the study period (June-November 2013). A total of 782 GNB were isolated. Out of 782, 172 were carbapenemase producer which were taken for present study. The entire testing was done under strict internal quality control using American type culture collection (ATCC) strains. Results: During the study period, 782 were examined. Out of 782 strains, 172 were found to produce carbapenemase activity. Out of 172 GNB strains, 164 (95.34%) were sensitive Colistin. Out of 164, 57 (34.75%) isolates sensitive to Colistin were found to be positive for extended spectrum beta-lactamase (ESBL) and carbapenemase production and 107 (65.24%) produced only carbapenemase. Among the resistant strains (08), 3 (37.5%) showed both carbapenemase and ESBL production and 5 (62.5%) were found to be positive only for carbapenemase production. Conclusions: Use of Colistin as therapeutic option can be increased by better understanding of the pharmacokinetics and pharmacodynamics of Colistin and its methanesulphate will allow the design of appropriate dosing regimens for maximizing efficacy while minimizing toxicity and the development of resistance.

Keywords: Carbapenemase, colistin, gram-negative bacilli, multi-drug resistant

How to cite this article:
Shrivastava G, Bhatambare GS, Patel K. Evaluation of in vitro sensitivity of Colistin to carbapenemase producing gram-negative bacilli. Sifa Med J 2014;1:31-3

How to cite this URL:
Shrivastava G, Bhatambare GS, Patel K. Evaluation of in vitro sensitivity of Colistin to carbapenemase producing gram-negative bacilli. Sifa Med J [serial online] 2014 [cited 2023 Mar 23];1:31-3. Available from: https://www.imjsu.org/text.asp?2014/1/3/31/138309

  Introduction Top

Colistin (Polymyxin E) is one of the polymyxin antibiotics produced by Bacillus colistinus. Polymyxins were discovered in 1947 and first reported by Koyama & coworkers and was originally thought to be distinct from Polymyxins, but was later proven to be identical to Polymyxin E. [1],[2],[3],[4] It has been available since 1959 for the treatment of infection caused by gram-negative bacteria. [5] However, when early clinical reports suggested a high incidence of toxicity, [6],[7] its use was reduced when the potentially less toxic aminoglycoside and other anti-pseudomonal agents became available. One of the greatest accomplishments of modern medicine has been the development of antibiotics for the treatment of potentially fatal infection. Unfortunately, the past two decades have seen a marked decline in the discovery and development of novel antibiotics and a remarkable increase in resistance to those currently available. [8] In particular, there is substantial concern worldwide with the mounting prevalence of infection caused by multi-drug resistant (MDR) gram-negative bacilli (GNB), especially Pseudomonas aeruginosa, Klebsiella pneumonia, Escherichia coli, Acinetobacter, for these species polymyxin are sometime the only available active antibiotics [9] since there has been no drug development for gram-negative infection. Therefore, clinicians and microbiologist have been forced to use Colistin as the remerging antibiotic for MDR gram-negative infection. In critically ill patients with such infections, Colistin is increasingly being used as salvage therapy. [10],[11] Although the Tigicycline has significant activity against MDR Acinetobacter, it is not active against Pseudomonas due to efflux by MexXY-Opr M. [12]

  Materials and Methods Top

Present study was carried out in the Microbiology department in a tertiary care hospital and teaching institute; during the study period (June-August 2013), a total of 782 GNB were isolated from routine samples. Out of those, 172 were carbapenemase producer which were used for the present study. The bacterial isolates were subjected to antibiotic susceptibility testing by standard Kirby Bauer Disc Diffusion methods. [13] Susceptibility patterns of the bacterial isolates were determined following panel of antimicrobial agents as recommended by Clinical laboratory standard Institute (CLSI). Antibiotic discs (10 μg Colistin) supplied by Hi Media, Mumbai, India and Escherichia coli ATCC25922 was used as control strain. Zone diameter was measured in mm, interpreted as per CLSI guidelines. The identification of bacterial isolates and their antimicrobial susceptibilities were also confirmed using VITEK-2 Compact (Bio mericux France). Carbapenemase production was screened by Modified Hodge and Hodge test and two disk diffusion methods were used for ESBL detection. [14] Isolates are examined for the expansion of the cefotaxime + claviulanic acid inhibition zone adjacent to disk containing cefotaxime alone. In the second method, a disk containing 30 mg of ceftazidime is placed adjacent to a combination disk containing ceftazidime 30 mg with clavulanic acid 10 mg on sterile Muller Hinton agar inoculated with ESBL positive and non-ESBL standard culture, an expansion of >5 mm indicate ESBL production. [14] The entire testing was done under strict internal quality control using ATCC (Escherichia coli ATCC 35218) strains. The present study has been approved by ethical committee of our institute.

  Results Top

During the study period, 782 isolates were obtained. Out of these 782 isolates, 172 showed carbapenemase production. Out of the 172 (21.99%) isolates, 60 (34.88%) were Klebsiella pneumoniae, 47 (27.32%) were Escherichia coli, 46(26.74%) were Pseudomonas aeruginosa, 11 (6.39%) were other member of enterobacteriace, and 8 (4.65%) were Acinetobacter spp., respectively [see [Table 1] for details]. Out of the 172 GNB, 164 (95.34%) were sensitive and 8 (4.65%) were resistant to Colistin. Out of 164, 57 (34.75%) were found to be positive for ESBL carbapenemase production and 107 (65.24%) produced only carbapenemase. Among the resistant strains (08), 3 (37.5%) showed both carbapenemase and ESBL production and 5 (62.5%) were found to be positive only for carbapenemase production.
Table 1: Showing the percentage of MDR, TDR, ESBL, and carbapenemase production

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  Discussion Top

The widespread resistance of microorganisms to antibiotics threatens to be a future medical disaster. Multi-resistance in GNB, including strains resistance to carbapenemase is also emerging as a global health issue. Gram-negative bacteria are very notorious for causing nosocomial infection, they are also well known for their MDR pattern. In a study by other workers, a total of 150 non-duplicate Acinetobacter clinical isolates were tested, including 89 Colistin sensitive and 61 Colistin-resistant isolates. [15] On the contrary, in our study, we have found 172 (21.99%) gram-negative isolates to produce carbapenemase and out of 172, 164 (95.34%) isolates were found sensitive to Colistin and 8 resistant. Out of 164 isolates, prevalence of carbapenemase and ESBL production was 37.5%, remaining isolates (65.24%) produced only carbapenemase. Our study also revealed that total drug resistance was high in Acinetobacter followed by Pseudomonas aeruginosa, Escherichia coli and Klebsilla pneuminiae. In this study, prevalence of MDR was found to be higher in Pseudomonas aeruginosa followed by Klebsiella pneuminae and Escherichia coli. Kwa et al., (2011) described 175 cases of non-cystic fibrosis (CF), patients who mostly had pneumonia and were given intravenous polymixin B (PMB) for infection caused by MDR GNB, with clinical response rates ranging from 47.3-50%. [16] Recently, a large cohort study by Falagas et al.,(2005) on intravenous Colistin showed that Colistin is a valuable antibiotic with acceptable nephrotoxicity and considerable effectiveness that depends on the daily dosage and infection site. [11] Garnacho-Montero et al., performed a preliminary evaluation of 35 cases of ventilator-associated pneumonia (VAP) caused by Acintobacter baumannii that were treated with intravenous Colistin or imipenem. [17] A clinical cure was reported in 57% of patients. These findings indicate that Polymyxins are as effective as carbapenems. Kallel et al., determined the efficacy and safety of Colistin in the treatment of VAP caused by pan-drug-resistant Acinetobacter baumanii or Pseudomonas aeruginosa. [18] Sixty patients included in this study were treated by Colistin intravenously. A favorable clinical response to antibiotic therapy for VAP occurred in 45 patients (75%). None of the patients developed renal failure in this study, and their results showed that Colistin can be a safe and effective option in the treatment of VAP caused by Pseudomonas aeruginosa or Acinetobacter baumanii. Recently, Cho et al., reported the effectiveness of Colistin in the treatment of major burn patients in South Korea. [19] López-Alvarez et al., (2009) [20] suggested that intraventricular administration of Colistin methane sulfonate (CMS) is effective for the treatment of ventriculitis caused by MDR Acinetobacter baumannii. In short, contemporary clinical studies have demonstrated that treatment with CMS could be a better option than no treatment. Present study also focuses mainly on in vitro sensitivity of Colistin against carbapenemase producer GNB. Hence, Colistin will be an important antimicrobial option against carbapenemase producer GNB in the recent scenario. Recommendation of Colistin for different patients to maximize the antibacterial activity and minimize the development and prevalence of resistance is observed. We believe that Colistin will be the "last line" therapeutic drug against MDR carbapenemase producer GNB in the coming year.

  Acknowledgement Top

The authors wish to thank the Chairperson and Dean of the institute for providing laboratory facilities and healthy working atmosphere during the study period. The authors are also thankful to the technical staff of the institute for providing necessary helping hand during the endeavor. Finally, the corresponding author would like to thank her husband Mr. Ankur Shrivastava and her parents for their love, encouragement and support. She dedicates all her success to each one of them.

  References Top

1.Ainsworth GC, Brown AM, Brownlee G. Aerosporin, an antibiotic produced by Bacillus aerosporus Greer. Nature 1947;159:263.  Back to cited text no. 1
2.Stansly PG, Shepherd RG, White HJ. Polymyxin: A new chemotherapeutic agent. Bull Johns Hopkins Hosp 1947;81:43-54.  Back to cited text no. 2
3.Koyama Y, Kurosasa A, Tsuchiya A, Takakuta K. A new antibiotic "colistin" produced by spore-forming soil bacteria. J Antibiot (Tokyo) 1950;3:457-8.  Back to cited text no. 3
4.Suzuki T, Hayashi K, Fujikawa K, Tsukamato K. The chemical structure of polymyxin E: The identities of polymyxin E1 with colistin A and polymyxin E2 with colistin B. J Biochem 1965;57:226-7.  Back to cited text no. 4
5.Ross S, Puig J, Zaremba EA. Colistin: Some preliminary laboratory and clinical observations in specific gastroenteritis in infants and children. Antibiot Annu 1959-1960;7:89-100.  Back to cited text no. 5
6.Ryan KJ, Schainuck LI, Hickman RO, Striker GE. Colistimethate toxicity. Report of a fatal case in a previously healthy child. JAMA 1969;207:2099-101.  Back to cited text no. 6
7.Koch-Weser J, Sidel VW, Federman EB, Kanarek P, Finer DC, Eaton AE. Adverse effects of sodium colistimethate. Manifestations and specific reaction rates during 317 courses of therapy. Ann Intern Med 1970;72:857-68.  Back to cited text no. 7
8.Infectious Diseases Society of America. Bad bugs, no drugs. [Last accessed on 2006 Jul 23].  Back to cited text no. 8
9.Li J, Nation RL, Milne RW, Turnidge JD, Coulthard K. Evaluation of colistin as an agent against multi-resistant Gram-negative bacteria. Int J Antimicrob Agents 2005;25:11-25.  Back to cited text no. 9
10.Karabinis A, Paramythiotou E, Mylona-Petropoulo D, Kalogeromitros A, Katsarelis N, Kontopidou F, et al. Colistin for Klebsiellapneumoniae-associated sepsis. Clin Infect Dis 2004;38:e7-9.  Back to cited text no. 10
11.Falagas ME, Kasiakou SK. Colistin: The revival of polymyxins for the management of multidrug-resistant gram-negative bacterial infections. Clin Infect Dis 2005;40:1333-41.  Back to cited text no. 11
12.Dean CR, Visalli MA, Projan SJ, Sum PE, Bradford PA. Efflux mediated resistance to tigecycline (GAR-936) in Pseudomonasaeruginosa PAO1. Antimicrob Agents Chemother 2003;47:972-8.  Back to cited text no. 12
13.Cheesbrough M. Medical Laboratories manual for tropical countries. Tropical Health Technology. Vol. 2. London: Butterworth; 2002. p. 479.  Back to cited text no. 13
14.Bacterial identification flow charts and schemes: A guide to part III. In: Forbes BA, Sahm DF, Weissfeld AS, editors. Bailey and Scott's Diagnostic Microbiology. 12 th ed. Missouri: Mosby Elsevier; 2007. p. 251-3.  Back to cited text no. 14
15.Arroyo LA, Mateos I, González V, Aznar J. In vitro activities of tigicycline, minocycline, and colistin- tigicyline combination against multi- and pandrug-resistant clinical isolates of acinetobacter baumannii group. Antimicrob Agents Chemother 2009;53:1295-6.  Back to cited text no. 15
16.Kwa AL, Falagas ME, Michalopoulos A, Tam VH. Benefits of aerosolized colistin for ventilator associated pneumonia: Absence of proof versus proof of absence. Clin Infect Dis 2011;52:1278-9.  Back to cited text no. 16
17.Garnacho-Montero J, Ortiz-Leyba C, Jimenez-Jimenez FJ, Barrero-Almodovar AE, Garcia-Garmendia JL, Bernabeu-Wittell M, et al. Treatment of multidrug-resistant Acinetobacterbaumannii ventilator-associated pneumonia (VAP) with intravenous colistin: A comparison with imipenem-susceptible VAP. Clin Infect Dis 2003;36:1111-8.  Back to cited text no. 17
18.Kallel H, Hergafi L, Bahloul M, Hakim A, Dammak H, Chelly H, et al. Safety and efficacy of colistin compared with imipenem in the treatment of ventilator-associated pneumonia: A matched case-control study. Intensive Care Med 2007;33:1162-7.  Back to cited text no. 18
19.Choi JY1, Park YS, Cho CH, Park YS, Shin SY, Song YG, et al. Synergic in-vitro activity of imipenem and sulbactam against Acinetobacterbaumannii. Clin Microbiol Infect 2004;10:1098-101.  Back to cited text no. 19
20.Lopez-Alvarez B, Martin-Laez R, Farinas MC, Paternina-Vidal B, García-Palomo JD, Vázquez-Barquero A. Multidrug-resistant Acinetobacter baumannii ventriculitis: Successful treatment with intraventricular colistin. Acta Neurochir (Wien) 2009;151:1465-72.  Back to cited text no. 20


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