Evaluation of the implementation of the objective structured clinical examination in health sciences education from a low-income context in Tunisia: A cross-sectional study

Background

Objective structured clinical examination (OSCE) is well-established and designed to evaluate students' clinical competence and practical skills in a standardized and objective manner. While OSCEs are widespread in higher-income countries, their implementation in low-resource settings presents unique challenges that warrant further investigation.

Aim

This study aims to evaluate the perception of the health sciences students and their educators regarding deploying OSCEs within the School of Health Sciences and Techniques of Sousse (SHSTS) in Tunisia and their efficacity in healthcare education compared to traditional practical examination methods.

Methods

This cross-sectional study was conducted in June 2022, focusing on final-year Health Sciences students at the SHSTS in Tunisia. The study participants were students and their educators involved in the OSCEs from June 6th to June 11th, 2022. Anonymous paper-based 5-point Likert scale satisfaction surveys were distributed to the students and their educators, with a separate set of questions for each. Spearman, Mann-Whitney U and Krusakll-Wallis tests were utilized to test the differences in satisfaction with the OSCEs among the students and educators. The Wilcoxon Rank test was utilized to examine the differences in students' assessment scores in the OSCEs and the traditional practical examination methods.

Results

The satisfaction scores were high among health sciences educators and above average for students, with means of 3.82 ± 1.29 and 3.15 ± 0.56, respectively. The bivariate and multivariate analyzes indicated a significant difference in the satisfaction between the students' specialities. Further, a significant difference in their assessment scores distribution in the practical examinations and OSCEs was also demonstrated, with better performance in the OSCEs.

Conclusion

Our study provides evidence of the relatively high level of satisfaction with the OSCEs and better performance compared to the traditional practical examinations. These findings advocate for the efficacy of OSCEs in low-income countries and the need to sustain them.

Staphylococcus aureus Ventilator-Associated Pneumonia: A Study of Bacterio-Epidemiological Profile and Virulence Factors

Ventilator-associated pneumonia (VAP) represents a major cause of nosocomial infections in the intensive care units in which Staphylococcus aureus is frequently involved. Better knowledge of this pathogen is required in order to enhance the patient’s treatment and care. In this article, we studied the bacteriological profile and virulence factors of S. aureus-related VAP on a 3-year period. We included a collection of S. aureus strains (n = 35) isolated from respiratory samples from patients diagnosed with VAP in the intensive care units. We studied the bacteriological aspects and we searched for the presence of virulence factors (SpA, FnbpA, Hla, and PVL genes) in the strains, and we also studied the clinical and biological aspects of the infections. The average age of our patients was of 36 years and they were predominantly males (sex ratio = 3.37). A severe head trauma or a history of coma was noted in 73.43% of the patients. The average duration of ventilation was 29 days. Among the studied strains, five were Methicillin-resistant S. aureus of which three expressed the mecA gene. Overall, the Hla gene was detected in 85.7% of the strains and it was more prevalent in Methicillin-susceptible than Methicillin-resistant strains (93.3% versus 40%; P = 0.014). FnbpA, Spa, and PVL genes were detected, respectively, in 80%, 45.7%, and 20% of the strains. Therefore, our studied strains were essentially associated with the production of Hla and FnbpA genes. It is, however, important to elucidate their expression in order to establish their role in the VAP pathogenesis.

Evolution of antimicrobial resistance in departments with high risk of cross infections in Tunisia

Background

Antimicrobial resistance is actually a real and ever-changing public health problem. The microbiology laboratory plays a key role to achieve collaboration with clinical services and the prevention and control of infection team.

Objective

Describe the bacterial ecology of departments with high risk of Health care associated infections and analyze the evolution of antimicrobial resistance.

Methods

A descriptive and retrospective study was carried out in the university hospital Sahloul. It concerned all strains isolated in departments with high risk of Health care associated infections. The study period was spread over 7 years from January 1st, 2010 to December 31th, 2016.

Results

A total of 6108 non-redundant bacterial strains were isolated. Isolated pathogens were mainly from the urology departement (n-2651, 43.4%).The most frequent isolated pathogens were Escherichia coli (n = 1329, 21,8%), K. pneumoniae (n = 992, 16,2%), and Acinetobacter baumannii (n = 763, 12,5%). Concerning these main isolated species, significant statistical differences were noticed in bacterial resistance evolution over the years. With E. coli, the evolution was essentially represented by an increase of amoxicillin, amoxicillin clavulanic, cefotaxime, gentamicin, and fluoroquinolones resistance. With K. pneumoniae, cefotaxime resistance was stable, however resistance to imipenem and gentamicin was increasing. There was also a significant increase in fluoroquinolone and aminoside resistance. With S. Aureus, an increase in methicillin resistance was detected from 11.1% in 2010 to 20% in 2016.

Conclusions

Antibacterial Drug Resistance is a dynamic and rapidly evolving phenomenon in our hospital. The most common MDR bacteria studied were enterobacteriaceae producing carbapenemase. The emergence of glycopeptid resistance in enterococci must be controlled in order to prevent its spread to the community and the transfer of staphylococcus resistance genes.

Key messages

Antibacterial Drug Resistance is a dynamic and rapidly evolving phenomenon in our hospital. The most common multi drug resistant bacteria studied were enterobacteriaceae producing carbapenemase.

Results of screening for emergent highly resistant bacteria in Tunisian intensive care units

Background

The infections caused by emergent highly resistant bacteria (eHBR) that develop in intensive care units (ICUs) may result in significant patient illnesses and deaths, extend the duration of hospital stays and generate added costs. Facing this problem, the screening that emphasizes early identification of colonized patients, reduces the prevalence and incidence of infection, improves patient outcomes and reduces healthcare costs. In this context, we have implemented a screening for eHBR in ICUs of Sahloul university hospital of Sousse (Tunisia), which we report in this study the first six-months outcomes.

Methods

Rectal swab cultures were collected to detect Vancomycin resistant enterococcus (VRE) and Carbapenemase producing Enterobacteriaceae (CPE) among patients admitted in six ICUs of Sahloul university hospital of Sousse (Tunisia) and more than three times, at least one week apart, between 1 June and 31 December 2018.

Results

During the study period 174 patients were screened. Of them, 69.5% were male and 73.6% were admitted in surgical ICU. In total, 161 and 152 samples were realized respectively for the detection of CPE and VRE. These samples were positive in 15% and 8.5% respectively for CPE and VRE. Klebsiella pneumoniae OXA 48 was the most isolated CPE (80%).

Conclusions

Our screening program helped us in infection control by early identification of patients, thereby facilitating an informed decision about infection prevention interventions. Moreover, these results encouraged us to improve and generalize this program throughout the hospital.

Key messages

eHRB screening becomes an important axis in the prevention of eHRB infections in our facilities. eHRB screening allows the reinforcement of the basic infection prevention and control measures.

The emerging extensively drug resistant bacteria in a university hospital in Tunisia in 2019

Background

The discovery of antibiotics revolutionized medicine in the 20th century, however the emergence of extensively drug-resistant bacteria constitute a growing problem in our hospitals in Tunisia and across the world. This study aims to evaluate a screening program for Carbapenemase Producing Enterobacteriaceae (CPE) and vancomycin-resistant enterococci (VRE) undertaken by the Microbiology Laboratory of Sahloul University Hospital.

Methods

A descrptive and retrospective study was carried out between 01st April 2018 and 31th December 2019 in the university hospital Sahloul, in East Coast of Tunisia. The screening was based on rectal swabs; it concerned Medical Intensive Care Units, the postoperative unit, the paediatric and the nephrology departments. The rectal swabs were seeded on the chromID CARBASMART and chromID VRE agars(biomerieux, France)in search of CPE and VRE respectively. The identification and the antibiotic susceptibilities testing were performed using the Vitek2 System (biomerieux,France)

Results

In total, 191 patients were screened. Among them, 56% were admitted in Intensive Care Units, 9.95% in postoperative unit, 30.9% in paediatric department and 3.14% in the nephrology department. A total of 38 extensively drug-resistant bacteria were isolated: 20 CPE and 18 VRE. Among isolated CPE, 17 were identified as Klebsiella pneumonia: The ConfirmationKPC/MBLkit (RoscoDiagnostica, Denmark) supplemented with a disc of Temocillin showed that 7 strains produced metallo-carbapenemase and 10 strains produced OXA 48 carbapenemase. The other isoloted CPE were OXA-48 producers. All VRE were identified as Enterococcus faecium, Their Vancomycin and Teicoplanine MICs were greater than 32 mg/L.

Conclusions

Mastering the spread of extensively drug-resistant bacteria involves a multidisciplinary preventive strategy. It must include strict application of hygiene measures, early detection and isolation of carriers and rationalization of antibiotic use.

Key messages

the emergence of extensively drug-resistant bacteria constitute a growing problem that`s why Carbapenemase Producing Enterobacteriaceae and vancomycin-resistant enterococci screening is crucial. Anti microbial agents use must be rationalized.

Genomic analysis of in vivo acquired resistance to colistin and rifampicin in Acinetobacter baumannii

Acinetobacter baumannii is an opportunistic pathogen in healthcare facilities responsible for nosocomial infections mostly in immunocompromised patients. Colistin resistance is increasingly reported worldwide in A. baumannii. Here we describe the in vivo selection of colistin and rifampicin resistance in carbapenem-resistant A. baumannii. Antimicrobial susceptibility testing, plasmid analysis and whole-genome sequencing (WGS) were performed to fully characterise the resistome of two clinical isolates (AbS1 and AbS2) selected during treatment. Clinical isolate AbS1 remained susceptible to colistin, rifampicin and tigecycline, whilst AbS2 was susceptible only to tigecycline. PCR analysis revealed the presence of a bla_OXA-23-like carbapenemase gene. Kieser extraction revealed an ca. 74 kb plasmid harbouring bla_OXA-23. WGS revealed genomes of 3.8 Mbp in size with a G + C content of 38.9%, and both belonged to ST281 according to the Oxford MLST scheme and ST641 according to the Institut Pasteur scheme. The resistome was also composed of naturally occurring β-lactamases, i.e. ADC-25 cephalosporinase and OXA-82 oxacillinase, aminoglycoside resistance genes [aac(3)-Ia, aadA1 and aph(3')-VIa (aphA6)], and mutations in DNA gyrases explaining fluoroquinolone resistance. Single nucleotide polymorphism analysis revealed that both isolates were identical except for a 30-nucleotide duplication within the pmrB gene and a point mutation in the rpoB gene resulting in colistin and rifampicin resistance, respectively. This study highlights the genomic plasticity of A. baumannii under antibiotic pressure. The 10-amino acid duplication in PmrB affects colistin susceptibility by regulating lipopolysaccharide modification through the PmrAB two-component system. These findings provide further information on the molecular mechanisms leading to colistin resistance in A. baumannii.

Nosocomial urinary tract infections caused by extended-spectrum beta-lactamase uropathogens: Prevalence, pathogens, risk factors, and strategies for infection control

INTRODUCTION

Our goal was to investigate the prevalence and antibiogram pattern of extended spectrum beta-lactamase (ESBL) production among uropathogens using isolates from urine samples collected at the Department of Urology in the Sahloul Hospital, Tunisia We also aimed to identify the risk factors for nosocomial urinary tract infections (UTIs) in patients who underwent transurethral resection of the prostate (TURP) and the measures for infection control.

METHODS

Laboratory records of a five-year period from January 2004 to December 2008 were submitted for retrospective analysis to determine the incidence of ESBL infections. A total of 276 isolates were collected. A case-control study involving comparisons between two groups of patients who underwent TURP was performed to determine the risk factors for ESBL infection. Group 1, designated case subjects, included 51 patients with nosocomial UTI after TURP. Group 2, designated control subjects, consisted of 58 randomly selected patients who underwent TURP without nosocomial UTI in the same period. Factors suspected to be implicated in the emergence of ESBL infection were compared between the two groups in order to identify risk factors for infection. A univariate regression analysis was performed, followed by a multivariate one.

RESULTS

The annual prevalence of ESBL infection ranged from 1.3-2.5%. After performing univariate and multivariate regression analysis, the main risk factors for ESBL infections were identified as: use of antibiotics the year preceding the admission, duration of catheter use, and bladder washout (p=0.012, p=0.019, and p<0.001.

CONCLUSIONS

Urologists have to perform a good hemostasis, especially in endoscopic resections, in order to avoid bladder irrigation and bladder washout and to reduce the time of bladder catheterization, which is a strong risk factor of nosocomial UTIs.

Emergence of SHV-2a extended-spectrum beta-lactamases in clinical isolates of Pseudomonas aeruginosa in a university hospital in Tunisia

Extended-spectrum beta-lactamases (ESBLs) in Pseudomonas aeruginosa are increasingly reported worldwide. In our study, a total of 70 clinical isolates of multidrug-resistant P. aeruginosa were studied. Isoelectric focusing electrophoresis, PCR, and PCR product sequencing were designed to characterize the contained ESBLs. The Double Disk Synergy Test in Cloxacillin (250 microg/ml)-containing Mueller-Hinton agar plates with a 20 mm distance between disks was the most reliable ESBL-screening method. Seven out of 70 multidrug-resistant P. aeruginosa clinical isolates were positive for ESBL and have the bla(SHV-2a) ESBL gene. The bla(SHV-2a)-positive isolates were clonally related according to Enterobacterial Repetetive Intergenic Consensus-PCR (ERIC-PCR) results. The bla(SHV-2a) gene was found to be chromosomally located, and the flanking IS26 sequence in the immediate upstream region of the bla(SHV-2a) gene was detected in all SHV-2a-producing isolates. This is the first report of SHV-2a-producing P. aeruginosa isolates from Tunisia.

Dissemination of OXA-23-producing and carbapenem-resistant Acinetobacter baumannii in a University Hospital in Tunisia

Ninety-nine carbapenem-resistant Acinetobacter baumannii isolates were obtained from patients hospitalized between October 2005 and January 2007 at the University Hospital Sahloul, Sousse, Tunisia. Thirteen of those isolates produced the carbapenem-hydrolyzing oxacillinase OXA-23. All the OXA-23-positive isolates were clonally related, and the bla(OXA-23) gene was found to be chromosomally located and associated with an upstream-located insertion sequence ISAba1. This study further highlights the worldwide emergence of OXA-23-producing A. baumannii isolates.

[Clinical and epidemiological characterization of infections due to imipenem resistant Acinetobacter baumannii at the university hospital Sahloul, Tunisia]

OBJECTIVE

to characterize epidemiological and clinical features related to the multi-drug Acinetobacter baumannii infections in the university hospital Sahloul in Tunisia.

MATERIAL AND METHODS

retrospective study including twenty-four imipenem resistant Acinetobacter baumannii isolated from twenty patients hospitalized in different wards of the hospital. Study of clinical features related to the infection by multi-drug Acinetobacter baumannii, bacterial identification by classical identification scheme, antibiotic susceptibilities were determined by the disk diffusion method; genotyping was performed by arbitrarily-primed PCR.

RESULTS

the most incriminated ward was the intensive care unit with a high prevalence of septicaemia. All studied strains were multi-drug to all beta-lactams tested. Genotyping has shown the clonality of studied strains. Features incriminated in the acquisition of infection were essentially immunodeficiency, invasive manoeuvring and antibiotherapy.

CONCLUSION

multidrug Acinetobacter baumannii is increasingly isolated in our hospital. Rational use of antibiotics and rigorous application of hygienic rules could contribute to limit dissemination of such strains.

Résistance aux antibiotiques de Staphylococcus aureus résistant à la méticilline : détection des premières souches de sensibilité diminuée aux glycopeptides en Tunisie

The adaptation of Staphylococcus aureus to the hospital environment led to the acquisition of resistance to all antibiotics available in clinical practice. The aim of this study was to investigate the methicillin-resistant Staphylococcus aureus (MRSA) strains isolated in the F. Bourguiba hospital of Monastir (Tunisia). We determined the antibiotype of all Staphylococcus aureus strains identified. Susceptibility rates to fosfomycin, chloramphenicol, rifampicin and pristinamycin were 7%, 3%, 2% and 0%, respectively. The prevalence of MRSA was 15.5% (96 strains); their susceptible to gentamicin progressively increased. The minimum inhibitory concentration (MICs) of oxacillin, vancomycin and teicoplanin were evaluated for the 96 MRSA strains. We identified two MRSA strains (M4 and M41) showing reduced glycopeptides susceptibility. Further analysis revealed that M4 and M41 harbor the gene encoding the class S and class F proteins specific for the Panton-Valentine Leukocidin (PVL). The mecA gene was detected only in strain M41 which harbors the Staphylococcal Cassette Chromosome (SCCmec) type III. This is the first reported MRSA showing reduced susceptibility to glycopeptides in Tunisia. Regulatory surveillance of susceptibility to antibiotics is needed to reduce the morbidity and the mortality rates as well as societal costs of S. aureus infections.

[Epidemiologic markers in Haemophilus influenzae]

Twenty-six strains of Haemophilus influenzae, isolated from diverse pathological products in two different hospitals in the center of Tunisia (Sousse-Monastir) have been compared with two different genotypic techniques: AP-PCR and pulsed-field gel electrophoresis. These two techniques showed a high discriminating power. The combination of the results of both techniques were complementary and have individualized twenty-five heterogeneous patterns among the twenty-six strains. Among the strains of respiratory origin, only two were identical, they have been isolated from two patients hospitalized in the same period and the same hospital. Excepted the two above mentioned cases, this study showed a high genetical heterogeneity of the strains.

Group A streptococci in children with acute pharyngitis in Sousse, Tunisia

A 1-year prospective study in 2 paediatric outpatient clinics in Sousse, Tunisia, aimed to determine the presence of group A streptococci in acute pharyngitis cases and carriers, and the distribution of the serotypes and biotypes. Group A streptococci were found in 9.0% of throat swabs from 155 controls and 17.7% from 474 patients [P < 0.05]. Of 43 strains isolated from patients and submitted for typing, 15 different types were identified, the most common being M75 [14 strains; 32.5%], M9 [6 strains; 14.0%], M76 [5 strains; 11.6%] and M12 [4 strains; 9.3%]. Three strains were non-typeable [7.0%]. Biotyping of the strains showed 3 predominant biotypes:biotype 3 [n = 14], biotype 2 [n = 11], and biotype 1 [n = 7]