Magnitude of Biofilm Formation and Antimicrobial Resistance Pattern of Bacteria Isolated from Urinary Catheterized Inpatients of Jimma University Medical Center, Southwest Ethiopia

Medical Device-Associated Biofilm Infections and Multidrug-Resistant Pathogens

Medical devices such as venous catheters (VCs) and urinary catheters (UCs) are widely used in the hospital setting. However, the implantation of these devices is often accompanied by complications. About 60 to 70% of nosocomial infections (NIs) are linked to biofilms. The main complication is the ability of microorganisms to adhere to surfaces and form biofilms which protect them and help them to persist in the host. Indeed, by crossing the skin barrier, the insertion of VC inevitably allows skin flora or accidental environmental contaminants to access the underlying tissues and cause fatal complications like bloodstream infections (BSIs). In fact, 80,000 central venous catheters-BSIs (CVC-BSIs)-mainly occur in intensive care units (ICUs) with a death rate of 12 to 25%. Similarly, catheter-associated urinary tract infections (CA-UTIs) are the most commonlyhospital-acquired infections (HAIs) worldwide.These infections represent up to 40% of NIs.In this review, we present a summary of biofilm formation steps. We provide an overview of two main and important infections in clinical settings linked to medical devices, namely the catheter-asociated bloodstream infections (CA-BSIs) and catheter-associated urinary tract infections (CA-UTIs), and highlight also the most multidrug resistant bacteria implicated in these infections. Furthermore, we draw attention toseveral useful prevention strategies, and advanced antimicrobial and antifouling approaches developed to reduce bacterial colonization on catheter surfaces and the incidence of the catheter-related infections.

Incidence of catheter-associated urinary tract infections by Gram-negative bacilli and their ESBL and carbapenemase production in specialized hospitals of Bahir Dar, northwest Ethiopia

BACKGROUND

Catheter-associated urinary tract infections (CAUTIs) due to multidrug-resistant Gram-negative bacilli (GNB) is a common concern globally. Investigating the incidence of CAUTI and associated antibiotic resistance has paramount importance from the health care associated infections perspective. This study therefore assessed the incidence of CAUTIs due to GNB and the production of extended-spectrum beta-lactamase (ESBL) and carbapenemase among inpatients in specialized hospitals of Northwest, Ethiopia.

METHODS

A total of 363 patients with indwelling urinary catheters who were admitted in the hospital for > 48 h were consecutively enrolled and followed from 3 to 18 days. Data were collected through interviewing and review of medical records. Patients who developed at least one of the following: fever (> 38 OC), suprapubic tenderness, or costovertebral angle pain, coupled with a GNB positive urine culture of ≥ 103 CFU/mL with no more than two bacterial species were defined as CAUTI. The ESBL and carbapenemase production were detected and identified by chromogenic medium. Logistic regression analysis was done to identify associated factors.

RESULTS

From 363 patients followed, the incidence rate of CAUTI was 27.8 per 1000 catheter days. Catheterization for ≥ 8 days (AOR = 10.6, 95%CI:1.8-62.1) and hospitalization for > 10 days (AOR = 8.1, 95%CI: 2.4-27.2) were the factors significantly associated with CAUTIs. E. coli (n = 18, 34.6%), Proteus species (n = 7, 13.5%), and P. aeruginosa (n = 6, 11.5%) were the most frequent GNB. Isolates revealed high rates of resistance to amoxicillin-clavulanic acid (100%), cefazolin (n = 51, 98%), ceftazidime (n = 47, 90%) and cefotaxime (n = 46, 88%). Most of the GNB isolates (86.5%) were multidrug-resistant. Overall, 19.2% and 5.8% of GNB isolates were ESBL and carbapenemase producers, respectively.

CONCLUSIONS

Incidence of CAUTI with Gram-negative bacilli is high. As most of the GNB isolates are MDR and showed a super high rate of resistance to amoxicillin-clavulanic and third-generation cephalosporins, empirical treatment with these substances is virtually ineffective in patients with suspected GNB infection in Ethiopia. The expression of ESBL and carbapenemase among GNB isolates is also a concern. Therefore, improved infection prevention and control measures, careful use of catheters and third generation of cephalosporins are needed to improve patient outcomes and reduce the burden of CAUTIs and the spreading of antimicrobial resistance.

Antimicrobial resistance profiles of bacterial isolates from clinical specimens referred to Ethiopian Public Health Institute: analysis of 5-year data

BACKGROUND

Antimicrobial resistance is one of the common global public health problems. The emergence of antimicrobial resistance is multifactorial, and tackling its development is challenging. Consequently, infections caused by resistant bacteria are unresponsive to conventional drugs, resulting in prolonged and severe illnesses, higher mortality rates, and considerable healthcare costs. Therefore, understanding the antimicrobial resistance profiles of bacterial pathogens is essential to optimize treatments and reduce the risks associated with infections. This study aimed to determine the antimicrobial resistance patterns of bacterial isolates from different clinical specimens at the Ethiopian Public Health Institute (EPHI).

MATERIALS AND METHODS

The retrospective cross-sectional study was conducted on the bacterial culture and antibiotic susceptibility reports of different clinical specimens referred to the Bacteriology Laboratory of EPHI from September 2015 to August 2019. Standard bacteriological techniques were used for the isolation and identification of the bacteria. Data were extracted from 840 patients' records, which included the type of clinical sample cultured, the name of the bacteria, the representations of the antibiotics used for susceptibility testing, and the susceptibility results. Descriptive statistics were used to describe the bacterial isolates and the antimicrobial resistance profiles.

RESULTS

Eight types of clinical specimens were analyzed for bacterial isolates and urine specimens were the most analyzed. Ten different genera of bacteria were identified by culture. Almost all the isolates were gram-negative bacteria, while only one species of gram-positive (Staphylococcus aureus) was reported. Antibiotic sensitivity patterns were tested on 840 culture isolates. Escherichia coli strains revealed more than 57% resistance to seventeen antibiotics. Klebsiella pneumoniae showed nearly 70% or greater resistance rates for 17 of the antibiotics used. The overall detected multidrug resistance (MDR) was 64.29%. The highest MDR was reported in Acinetobacter strains (84%) followed by K. pneumoniae (80%).

CONCLUSIONS

The multidrug resistance rates found in this study were alarming. Strengthening antimicrobial resistance surveillance at the national level is mandatory, and antimicrobial sensitivity testing should be accessible at local diagnostic centers.

Antimicrobial resistance pattern of Klebsiella isolated from various clinical samples in Ethiopia: a systematic review and meta-analysis

BACKGROUND

The burden of Klebsiella drug resistance to antimicrobials is a major public health concern worldwide; particularly the problem is severe in developing countries including Ethiopia. Therefore, the aim of this systematic review and meta-analysis is to establish the pooled estimate of Klebsiella drug resistance; and antimicrobial-specific resistance pattern among Klebsiella clinical isoaltes in Ethiopia.

METHODS

Articles were searched from PubMed, Google Scholar, and Science direct and grey literature from 2009 to 2019. Four authors have independently extracted data on the prevalence and antimicrobial resistance pattern of the isolates. Statistical analysis was conducted by using Open meta-analyst (version 3.13) and Comprehensive meta-analysis (version 3.3). The main outcome measures were the overall Klebsiella resistance; and drug-specific resistance patterns. A random-effects model was used to determine the pooled resistance prevalence with 95% confidence interval (CI), and significant heterogeneity was considered at p < 0.1; and I2 > 50% using DerSimonian and Laird method. In addition, subgroup analyses were conducted to improve the outcome.

RESULT

We obtained 174 potentially relevant studies through searching electronic databases, and finally, 35 eligible studies were included for meta-analysis. A total of 13,269 study samples participated, from which 1017 Klebsiella species were isolated. The overall Klebsiella resistance in Ethiopia was found to stand at 53.75% (95% CI: 48.35-58.94%). Based on the subgroup analyses; the highest (64.39%); and lowest (46.16%) values were seen in Southern Nations, Nationalities, and Peoples of Ethiopia; and Tigray regions respectively; and the highest Klebsiella resistance was reported to ampicillin (90.56%), followed by amoxicillin (76.01%) and trimethoprim-sulfamethoxazole (66.91%). A relatively low level of resistance rate was observed to amikacin (16.74%) and cefoxitin (29.73%).

CONCLUSION

The pooled Klebsiella resistance was found to be considerably high (53.75%) to most of the essential antibiotics in Ethiopia. Klebsiella was highly resistant to ampicillin and amoxicillin but relatively lower to amikacin. Therefore, appropriate interventional strategies need to be taken to address the emerging resistance of Klebsiella species.

Hospital-Based Air-Borne and Surface-Borne Bacterial Pathogens and Their Antimicrobial Profiles in Wolaita Sodo, Southern Ethiopia

Background. It is well documented that hospital environments are the niche/reservoir of many clinically important microorganisms, including multidrug-resistant air-borne and surface-borne pathogens. This problem is the most pressing public health concern, particularly in developing countries like Ethiopia, due to its poor infection management system. This study was planned to detect air-borne and surface-borne bacterial pathogens and their antimicrobial resistance patterns in Wolaita Sodo University Comprehensive Hospital, Southern Ethiopia. Method. A laboratory-based cross-sectional study was conducted from May to July 2021. Swabbing and open-plate sample collection methods were used to collect specimens. Standard bacteriological techniques were used to isolate and identify bacterial pathogens. The Mueller-Hinton agar was used to detect the drug susceptibility pattern of bacteria by using the Kirby-Bauer disc diffusion method. Result. From a total of 323 samples tested, 118 (36.5%) showed the growth of bacteria. The detection rate of bacterial pathogens in the intensive care unit (35.4%) was higher than in operation theater. From the total of 118 bacterial isolates, 39.8%, 27.9%, 20.3%, and 11.5% of S. aureus, P. aeruginosa, Klebsiella pneumoniae, and E. coli, respectively, were surface-borne. Whereas 37%, 25%, 20.83, and 16.6% of S. aureus, P. aeruginosa, Klebsiella species, and E. coli, respectively, were air-borne. S. aureus showed a 19.04 to 80.9% range of antimicrobial resistance to different classes of antibiotics from surface specimens. A 12.5–100% range of antibiotic resistance levels was detected for all Gram-negative surface-borne bacterial pathogens. P. aeruginosa was 66.7%, 73.3%, and 73.3% resistant to gentamicin, chloramphenicol, and ceftriaxone, respectively. K. pneumoniae showed 75% and 87.5% resistance to ceftriaxone and ciprofloxacin, respectively, and a completely ampicillin-resistant E. coli was detected. From a total of 48 bacterial pathogens identified from surfaces in the intensive care unit, 34 (70.8%) developed multidrug resistance. Conclusion. A significant prevalence of surface-borne bacterial pathogens was detected. This study revealed that S. aureus, P. aeruginosa, K. pneumoniae, and E. coli were nosocomial infection concerns of the hospital, and this could be the reason for different types of hospital acquired infections in the study area. A high prevalence of MDR was detected in the most surface-borne bacterial isolates.

Evaluation of Biofilm Formation and Virulence Genes and Association with Antibiotic Resistance Patterns of Uropathogenic Escherichia coli Strains in Southwestern Iran

Background: Uropathogenic Escherichia coli (UPEC) strains, encoding superficial and secretory virulence factors, can lead to colonization and facilitation of bacterial growth in the host urinary tract, causing Urinary Tract Infection (UTI). Objectives: This study determined the ability of biofilm formation by the Congo red agar method, the presence of virulence genes using the multiplex polymerase chain reaction (PCR) method, and the relationship between biofilm formation and antibiotic resistance patterns and virulence genes in E. coli clinical isolates in Yasuj. Methods: This cross-sectional study was performed on 144 UPEC isolates collected in 2017. Biofilm formation was detected by the Congo red agar phenotypic assay and virulence factors by the multiplex PCR method. Antibiotic resistance tests were performed by the Kirby-Bauer method. Results: Out of 144 isolates of E. coli, 22 (19.4%) isolates showed to be strong biofilm producers, 27 (23.8%) moderate biofilm producers, and 64 (56.3%) weak biofilm producers. A significant relationship was observed between biofilm-producing strains and resistance to ampicillin (P = 0.020) and cotrimoxazole (P = 0.038). The virulence genes in strong biofilm producers included iutA (95%), FimH (93%), ompT (90%), PAI (90%), and TraT (81%) genes. The phylogroup B2 carried the most virulence genes. A significant correlation was observed between E. coli phylogenetic groups and aer (P = 0.019), iroN (P = 0.042), and ompT (P = 0.032) virulence genes. Conclusions: The results of this study showed a high prevalence of virulence genes, and antibiotic-resistant E. coli strains capable of biofilm formation. The results of this study may help elucidate the pathogenesis of UPEC and facilitate better treatment strategies for patients with UTIs in this geographic area.

Catheter-Associated Urinary Tract Infection: Incidence, Associated Factors and Drug Resistance Patterns of Bacterial Isolates in Southern Ethiopia

Introduction

Catheter-associated urinary tract infections (CAUTIs) are the most common nosocomial infection and a leading cause of morbidity. The aim of this study was to determine the prevalence, associated factors and antibiogram of the bacterial isolates among CAUTIs patients.

Methods

A facility-based, cross-sectional study was conducted from March to December 2019 at Arba Minch General Hospital, Southern Ethiopia. Clinical and socio-demographic data were obtained using a questionnaire. Clean catch midstream urine samples were collected and inoculated onto blood agar, MacConkey agar, and cysteine lactose electrolyte deficient agar (CLED). The inoculated culture media were incubated in an aerobic atmosphere at 37°C for 24 h. After overnight incubation, the bacterial growth on the respective media was inspected visually and graded for the presence of significant bacteriuria. A significant bacteriuria was considered, if pure culture at a concentration of ≥10⁵ colony forming unit (CFU)/mL. All isolates were further identified using colony morphology and biochemical tests. Antimicrobial sensitivity was determined by modified Kirby–Bauer disc diffusion method. Data were analyzed using SPSS version 25. P-value less than 0.05 was used as statistical significance.

Results

The overall incidence of symptomatic CAUTIs was 39/231 (16.8%). Independent predictors of CAUTIs were prolonged (≥7 days) catheterization (AOR = 3.6, 95% CI = 1.0–12.2), diabetes mellitus (AOR = 5.3, 95% CI = 1.4–19.6) and insertion of catheter in surgical ward (AOR = 3.6, 95% CI = 1.08–12.28). The most common bacterial isolates were E. coli 17/42 (40.5%), Klebsiella species 9/42 (21.4%) and Enterococcus species 5/42 (11.9%). High (>80%) drug resistance was observed against cotrimoxazole, cefoxitin and tetracycline. Ciprofloxacin and nitrofurantoin were the most active drugs. The overall prevalence of MDR among isolates was 37/42 (88.1%). Most bacterial isolates 30/42 (71.4%) were biofilm producers.

Conclusion

High levels of drug resistance were observed to commonly used antibiotics. In our study, biofilm-producing bacterial isolates were the predominant cause of CAUTIs. Therefore, continuous surveillance of antimicrobial resistance patterns is necessary to help physicians in treatment and management of CAUTIs.

Prevalence of multidrug-resistant bacteria in Ethiopia: a systematic review and meta-analysis

OBJECTIVES

Multidrug-resistant (MDR) bacteria are a significant public-health threat worldwide, especially in low- and middle-income countries. Comprehensive data are important to understand the magnitude of multidrug resistance (MDR), however these are not available in Ethiopia.

METHODS

Five electronic databases and grey literature of Addis Ababa University Repository were searched for data regarding the prevalence of MDR bacteria in Ethiopia. OpenMetaAnalyst R1.3 was used for analysis using a random-effects model to determine the effect size. Heterogeneity among articles was checked using the inconsistency index (I²). Funnel plot was used to check for publication bias. The quality of each article was checked using the Newcastle-Ottawa checklist adapted for cross-sectional studies.

RESULTS

Through database searching, 2094 articles were identified, of which 37 fulfilled the study inclusion criteria. This review comprises 6856 bacteria, of which 4949 isolates were MDR. The overall pooled prevalence of MDR was 70.5% (95% CI 64.9-76.1%), with considerable heterogeneity (I² = 97.48%, P < 0.001). Funnel plot revealed no publication bias. Sidama (81.7%) had the highest MDR and Tigray (51.1%) the lowest. The greatest source of MDR was from multiple sites of infection (MSI) (76.8%); the least was from bloodstream infections (62.9%). MDR was higher in studies conducted on hospital-acquired infections (72.1%) compared with both hospital- and community-acquired infections (69.8%).

CONCLUSION

Our study indicates a high prevalence of MDR in Ethiopia. Sidama region, MSI and hospital-acquired infections showed the highest MDR in subgroup analysis. Regional hospitals should implement infection prevention and proper use of antibiotics in the community.

Bacterial profile and antimicrobial susceptibility patterns of isolates among patients diagnosed with surgical site infection at a tertiary teaching hospital in Ethiopia: a prospective cohort study

BACKGROUND

Globally, surgical site infections are the most reported healthcare-associated infection and common surgical complication. In developing countries such as Ethiopia, there is a paucity of published reports on the microbiologic profile and resistance patterns of an isolates.

OBJECTIVE

This study aimed at assessing the bacterial profile and antimicrobial susceptibility patterns of isolates among patients diagnosed with surgical site infection at Jimma Medical Center in Ethiopia.

METHODS

A prospective cohort study was employed among adult patients who underwent either elective or emergency surgical procedures. All the eligible patients were followed for 30 days for the occurrence of surgical site infection (SSI). From those who developed SSI, infected wound specimens were collected and studied bacteriologically.

RESULTS

Of 251 study participants, 126 (50.2%) of them were females. The mean ± SD age of the patients was 38 ± 16.30 years. The overall postoperative surgical site infection rate was 21.1% and of these 71.7% (38/53) were culture positive. On gram stain analysis, 78% of them were Gram-negative, 11.5% were Gram-positive and 10.5% were a mixture of two microbial growths. Escherichia coli accounted for (21.43%), followed by Pseudomonas aeruginosa (19.05%), Proteus species (spp.) 14.29%), Staphylococcus aureus (11.90%), Klebsiella species (11.90%), Citrobacter spp. (9.5%), streptococcal spp. (7.14%), Coagulase-negative S. aureus (CoNS) (2.38%) CONCLUSION: Gram-negative bacteria were the most dominant isolates from surgical sites in the study area. Among the Gram-negative bacilli, Escherichia coli were the most common bacteria causing surgical site infection. As there is high antibiotic resistance observed in the current study, it is necessary for routine microbial analysis of samples and their antibiogram.

Glabridin Averts Biofilms Formation in Methicillin-Resistant Staphylococcus aureus by Modulation of the Surfaceome

Staphylococcus aureus is an opportunistic bacterium of the human body and a leading cause of nosocomial infections. Methicillin resistant S. aureus (MRSA) infections involving biofilm lead to higher mortality and morbidity in patients. Biofilm causes serious clinical issues, as it mitigates entry of antimicrobials to reach the etiological agents. It plays an important role in resilient chronic infections which place an unnecessary burden on antibiotics and the associated costs. To combat drug-resistant infection involving biofilm, there is a need to discover potential anti-biofilm agents. In this study, activity of polyphenolic flavonoid glabridin against biofilm formation of methicillin resistant clinical isolates of S. aureus is being reported for the first time. Crystal violet assay and scanning electron microscopy evidences shows that glabridin prevents formation of cells clusters and attachment of methicillin resistant clinical isolate (MRSA 4423) of S. aureus to the surface in a dose dependent manner. Gel free proteomic analysis of biofilm matrix by LC-ESI-QTOF confirmed the existence of several proteins known to be involved in cells adhesion. Furthermore, expression analysis of cell surface proteins revealed that glabridin significantly down regulates an abundance of several surface-associated adhesins including fibronectin binding proteins (FnbA, FnbB), serine-aspartate repeat-containing protein D (SdrD), immunoglobulin-binding protein G (Sbi), and other virulence factors which were induced by extracellular glucose in MRSA 4423. In addition, several moonlighting proteins (proteins with multiple functions) such as translation elongation factors (EF-Tu, EF-G), chaperone protein (DnaK), glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and pyruvate kinase (PK) were detected on the cell surface wherein their abundance was inversely proportional to surface-associated adhesins. This study clearly suggests that glabridin prevents biofilm formation in S. aureus through modulation of the cell surface proteins.

Ultra-efficient Antibacterial System Based on Photodynamic Therapy and CO Gas Therapy for Synergistic Antibacterial and Ablation Biofilms

In recent years, with the emergence of various kinds of drug-resistant bacteria, existing antibiotics have become inefficient in killing these bacteria, and the formation of biofilms has further weakened the therapeutic effect. More problematically, the massive use and abuse of antibiotics have caused severe side effects. Thus, the development of ultra-efficient and safe antibacterial systems is urgently needed. Herein, a photodynamic therapy (PDT)-driven CO-controlled delivery system (Ce6&CO@FADP) is developed for synergistic antibacterial and ablation biofilms. Ce6&CO@FADP is constructed using a fluorinated amphiphilic dendritic peptide (FADP) and physically loaded with Ce6 and CORM-401. After efficiently entering the bacteria, Ce6&CO@FADP can rapidly release CO intracellularly by the massive consumption of the H₂O₂ generated during the PDT process, without affecting the generation of singlet oxygen (¹O₂). As such, the combination of CO and ¹O₂ exerts notable synergistic antibacterial and biofilm ablation effects both in vitro and in vivo (including subcutaneous bacterial infection and biofilm catheter models) experiments. More importantly, all biosafety assessments suggest the good biocompatibility of Ce6&CO@FADP. Together, these results reveal that Ce6&CO@FADP is an efficient and safe antibacterial system, which has essential application prospects for the treatment of bacterial infections and ablation of biofilms in vivo.