Search

The study determined the prevalence, antimicrobial resistant (AMR) determinants, and genetic characteristics of Escherichia coli and Klebsiella pneumoniae isolates from patients with diabetic foot infection (DFI) in a Tunisian hospital. A total of 26 Escherichia spp. and Klebsiella spp. isolates were recovered and identified by MALDI-TOF-MS. Antimicrobial susceptibility testing, the detection of AMR determinants and Shiga-like toxin genes, phylogenetic grouping, and molecular typing were performed. Twelve E. coli, 10 K. pneumoniae, 3 K. oxytoca, and 1 E. hermanii were isolated. A multidrug-resistant phenotype was detected in 65.4% of the isolates. About 30.8% of isolates were extended-spectrum β-lactamase (ESBL) producers and mainly carried blaCTX-M-15 and blaCTX-M-14 genes. One blaNDM-1-producing K. pneumoniae-ST1 strain was identified. Class 1 integrons were detected in 11 isolates and 5 gene cassette arrangements were noted: dfrA1+aadA1 (n = 1), dfrA12+aadA2 (n = 3), and dfrA17+aadA5 (n = 1). Other non-β-lactam resistance genes detected were as follows (number of isolates): aac(3')-II (3), aac(6')–Ib-cr(8), qnrB (2), qnrS (4), cmlA (2), floR (4), sul1 (11), sul2 (11), and sul3 (2). The phylogroup B1 was the most frequent (41.7%) among E. coli, and two ESBL-producing isolates corresponded to the ST131-B2 lineage. The ESBL- and carbapenemase-producing Enterobacteriaceae in DFIs are described for the first time in Tunisia. [ABSTRACT FROM AUTHOR]

Background. Pseudomonas aeruginosa is an invasive organism that frequently causes severe tissue damage in diabetic foot ulcers. Gap statement. The characterisation of P. aeruginosa strains isolated from diabetic foot infections has not been carried out in Tunisia. Purpose. The aim was to determine the prevalence of P. aeruginosa isolated from patients with diabetic foot infections (DFIs) in Tunisia and to characterize their resistance, virulence and molecular typing. Methods. Patients with DFIs admitted to the diabetes department of the International Hospital Centre of Tunisia, from September 2019 to April 2021, were included in this prospective study. P. aeruginosa were obtained from the wound swabs, aspiration and soft tissue biopsies during routine clinical care and were confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing, serotyping, integron and OprD characterization, virulence, biofilm production, pigment quantification, elastase activity and molecular typing were analysed in all recovered P. aeruginosa isolates by phenotypic tests, specific PCRs, sequencing, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. Results. Sixteen P. aeruginosa isolates (16.3 %) were recovered from 98 samples of 78 diabetic patients and were classified into 6 serotypes (O:11 the most frequent), 11 different PFGE patterns and 10 sequence types (three of them new ones). The high-risk clone ST235 was found in two isolates. The highest resistance percentages were observed to netilmicin (69 %) and cefepime (43.8 %). Four multidrug-resistant (MDR) isolates (25 %) were detected, three of them being carbapenem-resistant. The ST235-MDR strain harboured the In51 class 1 integron ( intI1 +aadA6+orfD+qacED1-sul1 ). According to the detection of 14 genes involved in virulence or quorum sensing, 5 virulotypes were observed, including 5 exoU -positive, 9 exoS -positive and 2 exoU/exoS -positive strains. The lasR gene was truncated by IS Ppu21 insertion sequence in one isolate, and a deletion of 64 bp in the rhlR gene was detected in the ST235-MDR strain. Low biofilm, pyoverdine and elastase production were detected in all P. aeruginosa ; however, the lasR -truncated strain showed a chronic infection phenotype characterized by loss of serotype-specific antigenicity, high production of phenazines and high biofilm formation. Conclusions. Our study demonstrated for the first time the prevalence and the molecular characterization of P. aeruginosa strains from DFIs in Tunisia, showing a high genetic diversity, moderate antimicrobial resistance, but a high number of virulence-related traits, highlighting their pathological importance.

Background: Good blood pressure control is one of the recommended targets in diabetic patient's management., Aim: To evaluate blood pressure (BP) control in hypertensive treated diabetic patients using ambulatory blood pressure measurement (ABPM)., Methods: Two hundred and six hypertensive treated diabetic patients were enrolled in this study (83 men and 123 women). Mean age were 60.3±9.6 years-old with mean diabetic duration of 9.1±8.2 years. All of them underwent 24 hours ABPM. Intervals between measurements were 20 minutes at diurnal period and 30 minutes at nocturnal period., Results: 28 patients (13.6%) only were at recommended target levels of blood pressure control (mean diurnal BP<130/80 mmHg and nocturnal BP<115/65 mmHg) and 137 patients were at the most bed control levels (mean diurnal BP ? 140/90 mmHg or nocturnal BP ? 125/75 mmHg). Bed controlled patients had mildly higher waist circumference (p=0.08). Poor BP control was associated with non dipper character (p<0.001), diabetic nephropathy (p<0.01) and diabetic retinopathy (p<0.01)., Conclusion: Our hypertensive treated diabetic patients were far from good blood pressure control. ABPM showed that the loss of nocturnal blood pressure fall was the most associated abnormality with poor BP control. Diabetic microangiopathy were more frequent in poor controlled patients.