Iraqi J Pharm Sci, Vol.20(2) 2011 Postoperative Wound Infections 59 Postoperative Wound Infections and the Antimicrobial Susceptibility in Baghdad Hospitals # Maysoon A. Merdaw* ,1 *Department of Clinical Laboratory Science ,College of Pharmacy,Baghdad University,Baghdad, Iraq. Abstract Nosocomial infections are one of the most important causes of mortality and morbidity in hospitals. These are major public health problems worldwide, but particularly in developing countries. The purpose of this research was to analyze the frequency of the microorganisms in the specimens taken from the surgical wounds, and to examine antimicrobial susceptibility for some isolates . Wound swabs were examined from June 2010 to January 2011. The isolates were identified by conventional methods, antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion method as per NCCLS guidelines.A total of 102 wound swabs were examined 22(21.56%) swabs were sterile and 80(78.43%) were positive for microorganisms. The results showed 27.2% positive for Pseudomonas aeruginosa, 25.0% positive for Coagulase positive Staphylococci, 20.0% positive for Enterococcus spp., 17.5% positive for Escherichia coli,15.0% positive for Klebsiella pneumonia,13.7% for Proteus mirabilis,and10.0% for Acinetobacter baumannii. Antimicrobial susceptibility testing showed that the rate of isolates of Imipenem Resistance Pseudomonas aeruginosa(IRPA) were 3.7% , 11.2% positive for Vancomycin Resistance Enterococci(VRE) ,13.7% positive for both Methicillin Resistance Staphylococcus aureus(MRSA)and Vancomycin Resistance Staphylococcus aureus(VRSA) ,and 11.2% positive for Vancomycin Intermediate Staphylococcus aureus(VISA). We found that postoperative wound infections increase with pre and post operative hospitalization that's mean the infections can be decrease by shortening the hospitalization time.Our results appear to be maintained with strategies for preventing nosocomial infection,permanent education, strong application of protocols and urging the implementation of strict infection control policy. Key words: nosocomial infection, surgical wound, antimicrobial susceptibility. الخالصة ْٔي يٍ انًشاكم انظحيح في األطاتاخ انًرعهمح تانًسرشفياخ ٔاحدج يٍ األسثاب انًًٓح نهًٕخ ٔاأليساضيح في انًسرشفياخ , انُاييح . انغسع يٍ ْرا انثحس ْٕ يعسفح األحياء انًجٓسيح في انًسحاخ انًأخٕذج يٍ جسٔح كم اَحاء انعانى ٔتاألخض في انثهداٌ انى كإٌَ انصاَي 0202ٔفحض انماتهيح انضد يايكسٔتيح نعدد يٍ انعزالخ. ذى جًع ٔفحض انًسحاخ نهفرسج يٍ حزيساٌ انعًهياخ , ٔجد يٍ )طسيمح األَرشاز تاسُعًال األلساص(. تأز -فكاٌ تطسيمح كيستيأيا فحض انماتهيح انضد يايكسٔتيح تانطسق انرمهيديح , 0200 كًا أظٓسخ انُرائج )يهٕشح( , %( يسحح يٕجثح30,87)02 )غيس يهٕشح( ٔ %( يسحح يعمًح:00,9)00, يسحح 020يجًٕع % coagulase positive Staph. ,02,2% نثكرسيا Pseudomonas aeruginosa ,09,2% يسحح يٕجثح نثكرسيا 03,0 % Klebsiella pneumonia ,07.3% نثكرسيا Escherichia coli,09.2نثكرسيا Enterococcus spp. ,03,9%نثكرسيا انماتهيح انضد يايكسٔتيح أظٓسخ َسة يٍ انعزالخ . Acinetobacter baumannii% نثكرسيا Proteus mirabilis ٔ02.2نثكرسيا % يٍ انعزالخ 00,0, ٔ %7,3ٔكاَد َسثرٓا Pseudomonas aeruginosa (IRPA)ايٍ تكرسي Imipenemانًمأيح نهًضاد MRSA(Methicillin% يٕجثح نكم يٍ تكرسيا Enterococcus ٔ07,3 (VRE)يٍ تكرسيا Vancomycinانًمأيح نهًضاد Resistance Staphylococcus aureus) ٔتكرسيا VRSA (Vancomycin Resistance Staphylococcus aureus) ٔ . اسرُرجُا يٍ تحصُا أٌ انرهٕز نجسٔح VISA(Vancomycin Intermediate Staphylococcus aureus) % نثكرسيا 00,0 ,ْٔرا يعُي أَّ يًكٍ ذمهيم َسثح األطاتاخ ترمهيم ) لثم ٔتعد اجساء انعًهياخ( ياتعد انعًهياخ يزداد تزيادج يدج انثماء في انًسرشفياخ طاتاخ انًسرشفياخ يسرٕجة انرصميف اندائى ٔانرطثيك انظازو نسياساخ انسيطسج عهى اطاتاخ أْرِ انًدج , نرا فأَّ نهحًايح يٍ انًسرشفياخ. Introduction Despite recent advances in the operative techniques and better understanding of the pathogenesis of the wound infections, postoperative wound infections continues to be a major source of morbidity and mortality for patients undergoing operative procedures. Surgical site infections (SSIs), as they are called today, accounted for 16% of all hospital-acquired infections, making them the third most frequent type of nosocomial infections in developed countries. The rates were higher in developing countries, and vary from 7% to 40% (1,2) . # Based on oral presentation in the eighth scientific conference of the College of Pharmacy /University of Baghdad held in 23-24 February 2011. 1 Corresponding author E- mail : maysoonmerdaw@yahoo.com Received : 6/2/2011 Accepted: 10/5/2011 Iraqi J Pharm Sci, Vol.20(2) 2011 Postoperative Wound Infections 60 The organisms causing most nosocomial infections usually come from the patient’s own body (endogenous flora). They also can come from contact with staff (cross-contamination), contaminated instruments and needles, and the environment (exogenous flora). Because patients are highly mobile and hospitalizations are becoming shorter, patients often are discharged before the infection becomes apparent. In fact, a large portion of nosocomial infections in hospitalized patients—and all from ambulatory care facilities—become apparent only after the patients are discharged. As a consequence, it is often difficult to determine whether the source of the organism causing the infection is endogenous or exogenous (3) ,it is very useful to explore the causes of these infections in order to timely detect and remove the causative agents (4,5) , with plentiful using of invasive technologies, severe and fatal nosocomial infections cause many damages every day (6) .These infections also contribute greatly to the economic costs of surgical procedures and the estimated range is 1.47-19.1 billion euro. This is a great problem, especially in resource of poor countries (7) , therefore ,knowledge about the frequency and distribution of nosocomial infections is important to improve infection control measures as well as to develop curative strategies which, in turn, will help us in decreasing incidence associated treatment cost (8) .In order to minimize the postoperative wound infections, it is important to create a safe environment by controlling four main sources of infection i.e. personnel, equipment , the environment and patient’s risk factors (9) .There are some indicators of the effects of infection control, most MRSA are hospital acquired and so this organism is a useful indicator. MRSA do not generally appear to be more virulent than sensitive strains but, because of their resistance patterns, they are more difficult to treat if infection occurs (10,11) .The rapid increase in enterococcal strains resistant to vancomycin (VRE) and other antibiotics and their ability to pass this trait on to other pathogens, i.e. Staphylococcus aureus, indicates an urgent and expanding clinical problem, VISA stands for S.aureus with intermediate resistance to vancomycin. VRSA stands for S. aureus with complete resistance to vancomycin. It is probable that S.aureus bacteria with intermediate or complete resistance to vancomycin would be resistant to most antibiotics commonly used for staphylococcal infections (12) . Pseudomonas aeruginosa is an important nosocomial pathogen with its ability to propagate on medical devices, hospital environment and even in disinfectants. It causes high morbidity and mortality in the services of oncology, hematology, surgery, burn and intensive care units (13,14) . The purpose of this research was to :  Know the incidence rate of nosocomial infection in surgical wards.  Study some factors influencing nosocomial infections in surgical wards.  Know the commonest organisms causing nosocomial infections.  Develop an effective antibiotic policy to deal with the common nosocomial infection. Materials and Methods Sampling The study was carried out on 102 patients admitted in the surgical wards of 4 hospitals in Baghdad city between June 2010 and January 2011.The age of patients was ranging from 12-79 years . Gender structure of patients was 54.90 % males and 45.09 % females. Surgical site infection was classified according to preoperative and post-operative hospitalization, type of the ward ,and types of bacterial organisms in each ward with examine the sensitivity of three isolated organisms .All laboratory testings were performed in the Kadhimyia Teaching Hospital . Media The media used for cultures were: Blood agar plates (containing blood agar base and 5% of human blood ) were used to facilitate the growth of fastidious microorganisms, particularly Gram positive bacteria . Mac Conkey agar was used for selective isolation of Enterobacteriacae. The plates were incubated for20-24 hrs. at 37c in bacteriological incubators. All isolates were identified by conventional biochemical testing according to the Medical Laboratory Manual 2004. Antimicrobial susceptibility testing was prepared by Kirby-Bauer disc diffusion method (15) on Muller-Hinton agar ( Difco), the following antibiotics were tested : Methicillin , Vancomycin, Imipenem, Gentamicin, Trimethoprim, Oxacillin, Penicillin, Piperacillin. Iraqi J Pharm Sci, Vol.20(2) 2011 Postoperative Wound Infections 61 Results and Discussion Nosocomial infections are a significant problem throughout the world and are increasing (16) . For example, nosocomial infection rates range from as low as 1% in a few countries in Europe and the Americas to more than 40% in parts of Asia, Latin America and sub-Saharan Africa (17) .The incidence of postoperative infections with bacterial growth was 78.43% from the 102 patients admitted and examined in our study, samples of wound swabs were examined: 80(78.43%) were positive and 22(21.56%) were negative ( Figure 1) , it was similar to the result of Maida Sisirak et al which was 83.7% in Bosnia (1) , and it was higher than incidence rates reported from developed countries in Western Europe, such as the United Kingdom (3.1%) and the Netherlands (4.3%) (18) . In Pakistan infection rate was 22.7% ( 19) , while in Nigeria 38.8% had Surgical Site Infections (20) , Figure 1: Review of examination samples and it was relatively higher in patients aged 12-29 years(88.2%), and in males 48(47.05%) than females 32(31.37%) (Table 1), it might be that most male patients had lower health care behaviors than female patients ,and this evidence supported the findings of previous studies (21,22) . These factors were not significant by multivariate analysis, the results supported the findings of previous studies, especially the studied variable as age. (23,24) Table 1: demographic data of patients with nosocomial infection (n=102) Age(Yrs) Examined samples No. % Incidence of infection No. % No. % Incidence of infection No. % 12-29 34 33.3% 30 88.2% (Male) 56 (54.90%) 48 (47.05%) 30- 39 23 22.5% 16 69.5% 40- 49 19 18.6% 16 84.2% 50- 59 10 9.8% 6 60.0% (Female) 46 (45.09%) 32 (31.37%) 60- 69 8 7.8% 6 75.0% 70- 79 8 7.8% 6 75.0% Total No. 102 80 We found 39.2% positive for abdominal wards which showed the highest positive (Table 2), this may be due to the types of operations in these wards, this finding is compatible to a previous study (25) . Table 2: Percentage of various nosocomial infections according to the type of surgical ward. %positive of Total No. No. of positive samples No. of samples Type of surgical ward 39.21 40 48 Abdominal 9.80 10 16 Gynecology 15.68 16 20 Orthopedics 13.72 14 18 Urology 78.43 80 102 Total Iraqi J Pharm Sci, Vol.20(2) 2011 Postoperative Wound Infections 62 The tables (3and 4 ) showed that postoperative wound infections increase with the hospitalization (pre and post operative) that's mean the infections can be decreased by shortening the hospitalization, and this findings are in agreement with a number of studies (1,25,26) . Antibiotic-susceptible microorganisms in body flora of the hospitalized patients can be replaced with antibiotic resistant strains which are present in hospital environment any time. Due to flora changes, prolonged hospitalization is a risk factor in all units and all types of nosocomial infections (19) . Table 3 : Surgical site infection according to pre-operative hospitalization Percentage% Infected Total Pre-op hospitalization 67.39 31 46 0-1 DAYS 78.94 15 19 2-3 DAYS 83.33 15 18 4-7 DAYS 100.0 19 19 >7 DAYS Table 4:Surgical site infection according to post operative hospitalization Percentage% Infected Total Post-op hospitalization 68.75 33 48 1-4 DAYS 78.94 15 19 5-10 DAYS 81.25 13 16 11-15 DAYS 100.0 19 19 >15 DAYS In the present study, Pseudomonas aeruginosa was the most frequent in the abdominal wards (23.3%) as in Table5 . Table 5: Showing organisms in Abdominal wards While in Gynecology wards we found that Coag-pos.Staph. (25.0%) was the most frequent (Table6). Table 6 : Showing organisms in Gynecology wards Percentage% No. of patients Culture 25.0 5 Coag- pos.Staph. 10.0 2 Escherichia coli 5.0 1 Pseudomonas aeroginosa 10.0 2 Klebsiella pneumoniae 0.0 _ Proteus mirabilis 0.0 _ Acinetobacter baumannii 20.0 4 Enterococcus spp. 30.0 6 Negative In Table 7 the most frequent reported microorganism in Orthopedics wards was Acinetobacter baumannii (27.2%) . Table 7: Showing organisms in Orthopedics wards In Urology wards(Table 8) ,the Escherichia coli was most common species(27.2%). Percentage% No. of patients Culture 18.1 4 Coag-pos.Staph. 9.0 2 Escherichia coli 18.1 4 Pseudomonas aeroginosa 0.0 _ Klebsiella pneumoniae 0.0 _ Proteus mirabilis 27.2 6 Acinetobacter baumannii 9.0 2 Enterococcus spp. 18.1 4 Negative Percentage% No. of patients Culture 10.0 6 Coag-pos.Staph. 6.6 4 Escherichia coli 23.3 14 Pseudomonas aeroginosa 16.6 10 Klebsiella pneumoniae 13.3 8 Proteus mirabilis 3.3 2 Acinetobacter baumannii 13.3 8 Enterococcus spp. 13.3 8 Negative Iraqi J Pharm Sci, Vol.20(2) 2011 Postoperative Wound Infections 63 Table8: Showing organisms in Urology wards Percentage% No. of patients Culture 22.7 5 Coag-pos.Staph. 27.2 6 Escherichia coli 9.0 2 Pseudomonas aeroginosa 0.0 _ Klebsiella pneumoniae 13.6 3 Proteus mirabilis 0.0 _ Acinetobacter baumannii 9.0 2 Enterococcus spp. 18.1 4 Negative The results showed 27.2% positive for Pseudomonas aeruginosa, 25.0% positive for Coagulase positive Staph., 20.0% positive for Enterococcus spp., 17.5% positive for Escherichia coli which were predominant to others as shown in (Table 9). Table 9 : Shows the most common isolates from wound swabs Percentage% No. Isolated microorganisms 25.0 20 Coag-pos.Staph. 17.5 14 Escherichia coli 27.2 21 Pseudomonas aeroginosa 15.0 12 Klebsiella pneumoniae 13.7 11 Proteus mirabilis 10.0 8 Acinetobacter baumannii 20.0 16 Enterococcus spp. The most frequently isolated microorganisms in the postoperative wound infections was Pseudomonas aeruginosa (27.2%) ,among these isolates, resistance rate for Imipenem were 3.7% . Because of increase of imipenem resistance, studies were done to determine the risk factors for IRPA infections, the isolates of IRPA were often multidrug resistant causing a difficulty in the treatment and control of these infections (13) .The genetic material that makes Vancomycin Resistant Enterococci(VRE) resistant to vancomycin, the vanA gene, can be transferred from the enterococci to other kinds of bacteria. If this vanA gene was to be transferred to MRSA bacteria, the end result would be S. aureus bacteria that are resistant to virtually all of our currently available antibiotics .(12,27) .The results showed 11.2% positive for VRE and13.7% positive for MRSA and VRSA and 11.2% positive for VISA (Figure 2). VISA/VRSA may spread from person-to-person in the same way as any S. aureus infection. S. aureus infections most often spread from person-to-person by direct contact. For example, in medical settings staphylococcal infections are often spread from patient to patient in unwashed health care workers' hands (1) . Figure 2: Percentage of MRSA , VRSA , VISA , VRE , IRPA in the Samples MRSA and VRSA on muller-hinton agar VISA on muller-hinton agar 13.7% 13.7% 11.2% 11.2% 3.7% 46.5% MRSA VRSA VISA VRE IRPA others Iraqi J Pharm Sci, Vol.20(2) 2011 Postoperative Wound Infections 64 Conclusions and Recommendations From this study, the following points emerged as priorities to be followed in the near future: definition of the antibiotic prophylaxis policy; reduction of preoperative length of hospitalization; increased follow up surveillance and setting up systematic surveillance; and reduction of the length of procedures through adequate training of the staff on proper surgical techniques and intra- operative infection control measures.Most of the postoperative infections can be prevented with readily available, relatively inexpensive strategies by:  adhering to recommended infection prevention practices, especially hand hygiene and wearing gloves.  paying attention to well-established processes for decontamination and cleaning of soiled instruments and other items, followed by either sterilization or high- level disinfection.  improving safety in operating rooms and other high-risk areas where the most serious and frequent injuries and exposures to infectious agents occur. Acknowledgements The author wish to thank the staff of the microbiology laboratory of Kadhimiyah Teaching Hospital especially Alia'a Jassim , Amira Abdullah, Ja’fer Abbas Hussein and we also wish to thank all the studied hospitals. References 1. Maida Š., Amra Z., Mirsada H. Methicillin-Resistant Staphylococcus Aureus (MRSA) As A Cause of Nosocomial wound Infections .Bosnian Journal of Basic Medical Sciences 2010; 10 (1): 32-37. 2. Ponce-de-Leon S. The needs of developing countries and the resources required. J Hosp Infect, 1991,18 (Suppl A): 376–381. 3. Simonsen L. Unsafe injections in the developing world and transmission of bloodborne pathogens: A review. Bull World Health Organ,1999, 77(10): 789– 800. 4. Martone W.J, Nichols R.I. Recognition, prevention, surveillance and management of surgical site infection: introduction to the problem and symposium overview. Clin. Infect. Dis. 2001;33(Suppl.2):567- 568. 5. Smyth E.T.M., Emmerson A.M. Surgical site infection surveillance. J. Hosp. Infect. 2000;45:173-184. 6. Payman S., Ali A. R., Masood Y. and Mohsen N., Neonatal Nosocomial Infections in Bahrami Children Hospital Indian J Pediatr 2006; 73 (3) : 197-20 . 7. Wenzel R.P. Global perspectives of infection control. In: Prevention and control of nosocomial infections ,2003, 4th ed. Philadelphia LWW. 14-33. 8. Leaper D.J., Van Goor H., Reilly J., Petrosillo N., Geiss H.K., Torres A.J., Berger A. Surgical site infection-European perspective of incidence and economis burden. Int. Wound J. 2004;1(4):247-273. 9. Damani N.N. Prevention of Surgical Site Infections. Manual of Infection Control Procedures. 2003:245-259. 10. Damani N.N. Methicillin-resistant Staphylococcus aureus. Manual of Infection Control Procedures. 2003; 121- 129. 11. Chaberny IF , Schwab F , Ziesing S, Suerbaum S, Gastmeier P. Impact of routine surgical ward and intensive care unit admission surveillance cultures on hospital-wide nosocomial methicillin- resistant Staphylococcus aureus infections in a university hospital: an interrupted time-series. analysis. J Antimicrob Chemother.2008Dec;62(6):1422-9. 12. Stefanie K., Markus H., Christian T., Johannes H. Enterococcal infections: host response, therapeutic, and prophylactic possibilities, Vaccine 22 , 2004; 822–830. 13. Fluit AC, Verhoef J, Schmitz FJ ,Imipenem-Resistant Pseudomonas aeruginosa : Risk Factors for Nosocomial Infections . Antimicrobial resistance in European isolates of Pseudomonas aeruginosa. European SENTRY Participants.Eur J Clin Microbiol Infect Dis 2000; 19: 370-4. 14. Zavascki AP, Cruz RP, Goldani LZ. Risk factors for imipenem-resistant Pseudomonas aeruginosa: a comparative analysis of two casecontrol studies in hospitalized analysis. J Antimicrob Chemother. 2008 Dec;62(6):1422-9. patients. J Hosp Infect 2005; 59: 96-101 15. Dr. M.K. Lalitha, Manual on Antimicrobial Susceptibility Testing ( under the auspices of Indian Association of medical Microbiologists ) last printed 21/9/2004 pp7-14. 16. Alvarado CJ . The Science of Hand Hygiene: A Self-Study Monograph University of Wisconsin Medical School and Sci - Health Communications ,2000. Iraqi J Pharm Sci, Vol.20(2) 2011 Postoperative Wound Infections 65 17. Gisselquist D . HIV infections in sub- Saharan Africa not explained by sexual or vertical transmission. Int J STD AIDS 2002; 13(10): 657–666. 18. Communicable Disease Surveillance Centre NINSS reports on surgical site infection and hospital acquired bacteremia.2000, 10: 213-216 . 19. Jan muhammad shaikh, bikha ram devrajani, syed zulfiquar ali shah, tauseefullah akhund, ishrat bibi., Frequency, pattern and etiology of nosocomial infection in intensive care unit: an experience at a tertiary care hospital , J Ayub Med Coll Abbottabad 2008 ; 20 (4) . 20. A. A. Oni, A. F. Ewete, A. T.Gbaja , A. F.Kolade, W. B . Mutiu , D. A. Adeyemo , Mini Review Nosocomial infections: surgical site infection in UCH Ibadan, Nigeria ,Nigerian Journal of surgical Research 2006: 8( 1) : 19-23. 21. Pipat L., Nattaya P., Varaporn P., Watchara K. , Nosocomial Surgical Site Infection among Photharam Hospital Patients with Surgery: Incidence, Risk Factors and Development of Risk Screening Form, J Med Assoc Thai , 2006; 89 ( 1) : 81-88 . 22. Danchaivijitr S, Tangtrakool T, Chokloikaew S. The Second Thai National Prevalence Study on Nosocomial Infections 1992.J Med Assoc Thai 1995;78 Suppl 2: S67-72. 23. Malone DL, Genuit T, Tracy JK, Gannon C,Napolitano LM. Surgical site infections: reanalysis of risk factors. J Surg Res 2002; 103: 89-95. 24. Pessaux P, Msika S, Atalla D, Hay JM, Flamant Y.Risk factors for postoperative infectious complications in noncolorectal abdominal surgery: a multivariate analysis based on a prospective multicenter study of 4718 patients. Arch Surg 2003; 138: 314-24. 25. Avdyl K., Faton H., Ruustem M., Gjyle M., Selvete K., Arsim K., Antigona D. Beqir N., Baton K. Dalip L., Ilir T., Surgical site infections in an abdominal surgical ward at Kosovo Teaching Hospital ,J Infect Developing Countries ,2007; 1(3):337-341. 26. Anderson Roger L, , Janice H, BS; Bond V Walter W, MS; Favero Martin S, Susceptibility of Vancomycin-Resistant Enterococci to Environmental Disinfectants. Infect. Control Hosp. Epidemiol. 1997; 18 ( 3): 195. 27. Gilmore MS, Coburn PS, Nallapareddy SR, Murray BE.Enterococcal virulence. The enterococci: pathogenesis, molecular biology, and antibiotic resistance. Washington, DC: ASM Press; 2002. p. 301–54.