Original article RETROSPECTIVE STUDY OF GRAM NEGATIVE BACILLI ISOLATES AMONG DIFFERENT CLINICAL SAMPLES FROM A DIAGNOSTIC CENTER OF KANPUR R.Sujatha 1,Nidhi Pal 2, Deepak S 3 1. Professor & Head, Department of Microbiology, Rama Medical college Hospital & research center, Kanpur 2. Ph.D. Scholar, Department of Microbiology, Rama Medical college Hospital & research center, Kanpur 3. PG students, Department of Microbiology, Rama Medical college Hospital & research center, Kanpur ABSTRACT Background: Gram negative bacilli with multiple drug resistance pose a greater risk for potentially untreatable infections with increased morbidity and mortality. Herein, this study was done to know the distribution of gram negative bacilli among different clinical samples and its antibiotic resistance pattern from a diagnostic center of Kanpur. Material &Methods: In this retrospective study, total 655 clinical samples details were taken from previous records of a diagnostic center of Kanpur Results: Among 655 clinical samples, 85.9% urine samples were received followed by pus(7.6%), sputum(3.2%), ear swab (2.2%) and semen (1.1%). E.coli was predominantly isolated from urine samples. K.pneumoniae, P.aeruginosa was commonly isolates from pus and sputum samples respectively. Imipenem and colistin was found to be the most sensitive drug for multidrug resistant gram negative bacilli. 32.1% of P.aeruginosa was found to be ESBL followed by K.pneumonieae (28.7%,), Citrobacter sp.(28.5%) and E.coli(24.5%). Conclusion: Hence to prevent the spread of the resistant bacteria, it is necessary to have antibiogram for hospitals to know the common organisms and their susceptibility patterns. Keywords: Gram negative bacilli, Antibiotic resistant pattern. INTRODUCTION There is numerous microorganism that cause increase morbidity. Among these microorganisms large number of gram negative bacilli belonging particularly to the members of the family Enterobacteriaceae and non-fermenting gram negative bacilli contributes to cause urinary tract infections, respiratory infections, bacteremia and nosocomial infections [1,2]. The major public health problem is increasing antimicrobial resistance among 1
gram negative bacilli, which limits the choice of antibiotics. Lack of local antibiotic policy in most of the setting is further exerting a selective antibiotic pressure for selecting out resistant strains [3]. This study was conducted to know distribution of gram negative bacilli among different clinical samples and antibiotic resistant pattern from a diagnostic center of Kanpur. MATERIAL AND METHODS This was a retrospective study, data was collected from a diagnostic center of Kanpur, over a period of six months (December 2016 to May 2017) sample details were recorded. Total 655 positive growth samples were noted. RESULT Among 655 clinical samples, 85.9% urine samples were received followed by pus and sputum. [Table 1] E.coli was the predominant gram negative bacilli followed by K.pneumoniae and P.aeruginosa.[Table 2] E.coli was commonly isolated from urine samples. In pus, K.pneumoniae was predominant isolates and P.aeruginosa was most commonly isolated from sputum samples. Other gram negative bacilli isolation from different samples was mentioned in [Table 3]. Antibiotic resistant pattern of isolated gram negative bacilli was showed in [Table 4]. 32.1% of P.aeruginosa was found to be extended spectrum β- lactamase followed by K.pneumineae, Citrobacter sp. and E.coli of 28.7%, 28.5% and 24.5% respectively [Table 5]. Table 1: Distribution of samples Samples No. of Percent samples (%) Urine 563 85.9 Pus 50 7.6 Sputum 21 3.2 Ear swabs 14 2.1 Semen 7 1.1 Total 655 Table 2: Distribution of Gram negative bacilli Organism No. of Percent samples (%) E.coli 534 81.5 K.pneumoniae 72 10.9 P.aeruginosa 28 4.2 K.oxytoca 14 2.1 Citrobacter 7 1.1 2
Table 3:Distribution of gram negative bacilli among different clinical samples Samples E.coli K.pneumoniae P.aeruginosa K.oxytoca Citrobacter Total Urine 513 29-14 7 563 Pus 14 29 7 - - 50 Sputum - 7 14 - - 21 Ear swabs - 7 - - - 14 Semen 7-7 - - 7 Total 534 72 28 14 7 655 Table 4: Antibiotic resistant pattern of gram negative bacilli Antibiotics E.coli N=534 K.pneumoniae N=72 P.aeruginosa N=28 K.oxytoca N=14 Citrobacter sp. N=7 AMP 70.79 69.44 67.86 64.29 71.43 CTX 72.55 72.22 71.43 78.57 71.43 CFS 62.70 40.28 60.71 50.00 57.14 AK 65.58 59.17 49.29 42.86 57.14 GEN 61.09 53.33 56.43 42.86 57.14 CIP 68.35 65.83 55.71 71.43 71.43 COT 72.47 76.39 70.71 71.43 71.43 NIT 46.25 47.22 100.00 35.71 42.86 IPM 34.42 38.06 42.14 21.43 42.86 PB 0 0 0 0 0 3
Table 5 ESBL producing Gram negative bacilli Microorganism Percent E.coli 24.5% K.pneumoniae 28.7% P.aeruginosa 32.1% Citrobacter sp. 28.5% DISCUSSION The microbial pathogens, as well as their antibiotic sensitivity patterns may change from time to time and place to place. Members of the family Enterobacteriaceae are among the most important bacterial human pathogens accounting for the majority of bacteria isolated from clinical samples [4]. In our study majority of the Gram negative isolates belonged to enterobacteriacea. Similar results were observed in a study by Balan K et al. [5] and only 4.2% of P.aeruginosa was isolated. In a study by Vipin Kumar et al. [6] 52 (58.42%) isolates of Escherichia coli were found to be the most common organisms followed by Klebsiella pneumoniae 18 (20.22%), Pseudomonas aeruginosa 11 (12.35%), Proteus vulgaris 3 (3.37%), Proteus mirabilis 2 (2.24%), Enterobacter aerogenes 2 (2.24%). Similar results were observed in our study but no Proteus species and Enterobacter aerogenes were isolated. That may be because of less sample population in this study and only diagnostic sample were included. In the present study Carbapenems were found to be most effective drugs against gram negative rods. This was comparable to a study conducted in India which showed the pattern as follows: E. coli (MRP; 95.45% and IMP; 98.45%), P. aeruginosa (MRP; 100% and IMP; 95.00%) [7]. In another study conducted in Iran.othe study showed 91.7% sensitivity against E.coli [8]. E. coli isolates were found to be imipenem (34.42%) resistant, P. aeruginosa (IMP; 42.14%) resistant, results are shown to be highly resistant in our study. K.pneumoniae show 38.06% of resistant for imipenem similarly a study in Saudi Arabia showed about higher resistant [9]. The rise in resistance of organisms to aminoglycosides and amoxicillin in this study may be due to increased consumption. The common form of resistance is mediated by lack of drug penetration (i.e., porin mutations and efflux pumps) and/or carbapenem-hydrolyzing - lactamases. In present study non lactose fermenting isolates, P.aeruginosa showed decreased 4
susceptibility to cefotaxime and ceftriazone were defined as extended spectrum β - lactamase (ESBL) phenotypes. Similarly, other gram negative bacilli i.e E.coli, K.pneumoniae and citrobacter species also show ESBL production (24.5%, 28.7% and 28.5% respectively ). No K.oxytoca was produced ESBL enzyme. Thus this study highlights the trends of multidrug resistance among gram negative isolates, therefore indicating an alarm of threat of emergence of drug resistant pathogens CONCLUSION Gram negative isolates are the most common cause of infections. High amount of antibiotic resistance is noted among the isolates. REFERENCES 1. Leng B, Meyers BR, Hirschman SZ, Keusch GT; Susceptibilities of gramnegative bacteria to combinations of antimicrobial agents in vitro.antimicrob. Agents Chemother., 1975; 8(2):164-71. 2. Lockhart SR, Abramson MA, Beekmann SE, Gallagher G, Riedel S, Diekema DJ et al.; Antimicrobial Resistance among Gram-Negative Bacilli Causing Infections in Intensive Care Unit Patients in the United States between 1993 and 2004. J Clin Microbiol., 2007; 45(10): 3352-3359. 3. Antibiogram of clinical isolates from a Healthcare Infection Control Practices Advisory Committee (HICPAC). Central for Disease Control and Prevention (CDC). Management of Multidrug-Resistant Organisms in Healthcare Settings; 2006. Available from http://www.cdc.gov/hicpac/pdf/mdr O/MDROGuideline2006.p df 4. Ekta G, Srujana M, Seema S, Benu D, Bimal KD, Arti K; Emerging resistance to carbapenems in a tertiary care hospital in north India. Indian J Med Res., 2006; 124(1): 95-98. 5. Balan K, Sujitha K, Vijayalakshmi TS; Antibiotic Susceptibility Pattern of Gram Negative Clinical Isolates in a Teaching Tertiary Care Hospital. Sch J App Med Sci., 2013; 1(2):76-79. 6. Vipin K, Rohit K M, Avantika C, Pramila G; Incidence of β-lactamase producing gram-negative clinical isolates and their antibiotic 5
susceptibility pattern: A case study in Allahabad. International Journal of Research in Pure and Applied Microbiology, 2011; 1(3): 36-39. 7. Devanand Prakash and Ramchandra Sahai Saxena. Distribution and Antimicrobial Susceptibility Pattern of Bacterial Pathogens Causing Urinary Tract Infection in Urban Community of Meerut City, India ISRN Microbiology. 2013:1-13. 8. Mohammadi MM, Feizabadi M. Antimicrobial resistance pattern of gram-negative bacilli isolated from patients at icus of army hospitals in Iran. Iranian journal of microbiology. 2011;3(1):36-40 9. A. J. Al-Zahran and N. Akhtar. Susceptibility patterns of extended spectrum beta-lactamase (ESBL)- producing Escherichia coli and Klebsiella pneumoniae isolated in a teaching hospital. Pakistan Journal of Medical Research,2005;44:64 67. CORRESPONDING AUTHOR: Dr. R.Sujatha Professor and Head of Department of Microbiology Rama Medical College Hospital& Research Centre,Mandhana, Kanpur, U.P. EmailID: drsujatha152@gmail.com 6