Infectious diseases have been major cause of morbidity and mortality all over the globe. The ability of bacterial pathogens to adapt and to overcome the antibiotic treatment has been challenging. We are now faced with a growing population of antibiotic resistant bacteria that threaten the effective patient management especially for patients with surgical site infections [1].
Surgical site infection (SSI) is defined as a proliferation of pathogenic microorganisms which develops in an incision site either within the skin and subcutaneous fat (superficial) and musculofascial layers (deep) in an organ or cavity, if opened during surgery [2].
Hospital acquired surgical site infections (HAIs) are one of the major health problems throughout the globe and are a serious complication affecting patients [3, 4]. Pathogens that are capable of surviving in the hospital environment for extended period and resist against disinfection are mainly more important for HAIs [3]. SSIs account for a high proportion of the total amount of HAIs and have an enormous impact on patients health care expenditure, morbidity, and mortality universally [4, 5]. SSIs account for 20–25% of all hospital acquired infections globally [6]. Globally, surgical site infection rates have been reported to range from 2.5–41.9% [6]. The possibility of acquiring hospital infection on hospitalized patients in relation to operation is high, since about 77% of death of patients with hospital acquired infections was reported to be associated with postoperative infections [4]. The rate of HAIs is noticeably higher in several developing countries [3, 4]. The amount of surgical patients in developing countries is also rising but surgical care given to the patients is deprived [4].
The majorities of post-operative wound infections are hospital acquired, and fluctuate from one hospital to the other and are associated with complications, increased morbidity and mortality [7, 8]. The emergence of bacterial antimicrobial resistance has made the selection of empirical treatment more complicated and costly [9]. Wound infections by resistant bacteria have further deteriorated the condition in this regard [10]. Fast spread of resistant microorganisms affected the effectiveness of antimicrobials and created world-wide crisis [11]. The situation is serious in developing countries owing to unreasonable prescriptions of antimicrobial agents [12].
Infection in wound constitutes a major obstacle to healing and can have an adverse impact on the patient’s quality of life as well as on the healing rate of the wound. Infected wounds are probably to be more painful, oversensitive and odorous, resulting in increased discomfort and inconvenience for the patient [13].
The common organisms that have been associated with wound infection consist of Staphylococcus aureus (S. aureus) which from a variety of studies have been found to account for 20–40% and Pseudomonas aeruginosa (P. aeruginosa) 5–15% of the nosocomial infection, with infection mainly following surgery and burns. Other pathogens such as Enterococci and members of the Enterobacteriaceae have been implicated, mainly in immune compromised patients and following abdominal surgery [14].
P.aeruginosa is one of the opportunistic nosocomial pathogens, which causes a wide spectrum of infections and leads to significant morbidity especially in immune compromised patients. Due to its high drug resistance nature to many antibacterial agents, the mortality rate is extensive [15, 16]. Specific treatment options to patients with post surgical wound infections are mainly dependent on recent data from antimicrobial susceptibility test results generated by clinical laboratories or properly surveyed epidemiological information collected from ongoing nosocomial infection surveillance [17]. However, recently updated summarized data on isolated P.aeruginosa from hospitalized patients and their antimicrobial susceptibility status to guide post operative wound infection in the country is scarce. Understanding the current levels of antimicrobial resistance throughout the country could improve clinical practice by guiding empirical antibiotic choice [18]. To overcome this challenge, we reviewed the available evidences reported on the burden of antimicrobial resistance among P.aeruginosa isolates from wound infection in Ethiopia in order to inform current clinical practice and future research interventions to address antibiotic resistance.
Thus, this systematic review aimed at determining the current antimicrobial resistance profile of Pseudomonas aeruginosa islolated from patients with wound infection in Ethiopia.
1.1. Antimicrobial resistance patterns in wound isolates, especially P.aeruginosa
Pseudomonas aeruginosa is one of the most common gram negative bacterial pathogens associated with nosocomial infections [19, 20]. In addition to this, it is also widely spread in community acquired infections. Resistance to different anti-Pseudomonal agents is increasing from time to time, which challenges the choice of suitable treatment. The carbapenems are commonly considered as the most reliable agents for treating P. aeruginosa infections. The appearance of multidrug resistant P. aeruginosa remains concern of public health practitioners globally [20, 23]. Patients with P. aeruginosa wound infections have greater need for debridement and they frequently require re-grafting due to loss of skin grafts or allograft [21]. Skin and soft tissue infections caused by P. aeruginosa are also associated with prolonged hospital stay and increased mortality [22]. The mortality and morbidity associated with P. aeruginosa are mostly endorsed to insufficient empirical therapy and/ or delay in the beginning of appropriate therapy [19, 20].
Emergence of multi-drug resistance in P. aeruginosa is being reported globally, due to the blanket use of antibiotics [24]. The raise in occurrence of multidrug resistant strains is caused by a permanent selective pressure of frequently used antibiotics. This selective antibiotic pressure leads to expansion of bacterial resistance by favoring quick evolution of the bacterial genome [25]. Treatment of infections caused by this pathogen is becoming complicated, because of the increased rate of drug resistance. Knowledge on the resistance pattern of the local microbial flora is necessary for choice of appropriate antibiotic therapy. In this study, increased resistance to gentamicin, ciprofloxacin, ceftazidime, cefoperazone-sulbactam and meropenem was observed among the in-patients during the first study period. Several studies have reported such high rates of antibiotic resistance in P. aeruginosa isolated from hospitalized patients [26–28].
According to a study conducted on Antimicrobial Susceptibility Patterns of the Bacterial Isolates in Post-Operative Wound Infections in a Tertiary Care Hospital, Kathmandu, Nepal, 100% of the Pseudomonas aeruginosa isolates were resistant to Cephalexin and Cotrimoxazole. The resistance status for Ceftriaxone and Ciprofloxacin were 50%. In this study all the Pseudomonas aeruginosa isolates were 100% sensitive to Amikacin, Gentamicin, Norfloxacin and Ofloxacin [29].
Clinico-microbiological study of Pseudomonas aeruginosa in wound infections and the detection of metallo-β-lactamase production conducted in India indicate that out of the 224 Pseudomonas aeruginosa isolates 38% showed resistance to gentamicin followed by ceftazidime (31⋅69%) and meropenem (33⋅03). In this report of the isolates, 100% were susceptible to polymyxin B and colistin, 92⋅8% were sensitive to imipenem [30].
A study on Antibiotics Susceptibility Pattern of Pseudomonas aeruginosa Isolated from Wounds in Patients Attending Ahmadu Bello University Teaching Hospital, Zaria, Nigeria indicates that strong resistance to cotrimoxazole (90.9%), amoxicillin (90.9%), tetracycline (81.8%) and augmentin (81.8%) [31].
Another study in the same country also shows that, resistance to different antibiotics against P. aeruginosa isolated from various samples was Ceftazidime (100%), Piperacillin-Tazobactum (99%), Amoxicillin Clavulanic Acid (91%), Amikacin (82%) and Ciprofloxacin (70%). In this study, over 65% of isolates were sensitive to Imipencem and 35% showed resistance to imepenem [32].
In Ethiopia a study conducted Prevalence of Multidrug Resistant Bacteria in Postoperative Wound Infections at Tikur Anbessa Specialized Hospital; Addis Ababa, Ethiopia of the 8 Pseudomonas aeruginosa isolated the resitance pattern were amoxicillin (100%), Amoxicillin-Clavulanic Acid and Sulphamethoxazole-Trimethoprim (87.5%) [32].
The antimicrobial resistance rates of P. aeruginosa are known to fluctuate extensively in different settings and period. Active inspection of trends in antibiotic resistance of P. aeruginosa is essential for the selection of suitable antimicrobial agent for empirical therapy. The objectives of this review were to assess the rates of antibiotic resistance and multidrug resistance among P. aeruginosa isolates from patients with wound infection.