High carriage of plasmid-mediated quinolone resistance (PMQR) genes by ESBL-producing and fluoroquinolone-resistant Escherichia coli recovered from animal waste dumps.

BACKGROUND: There has been a rise in the consumption of fluoroquinolones in human and veterinary medicine recently. This has contributed to the rising incidence of quinolone resistance in bacteria. This study aimed at the determination of the antibiotic resistance profile of ESBL-producing and fluoroquinolone-resistant E. coli (FQEC) isolated from animal waste obtained from the waste dumps of an agricultural farm and their carriage of genes encoding PMQR. METHODS AND RESULTS: Isolation of ESBL-producing E. coli from animal waste samples was done on CHROMagar ESBL, while presumptive isolates were purified, and identified via the detection of uidA gene. Susceptibility to a panel of ten antibiotics was done using the disc diffusion method, and detection of PMQR genes (qnrA, qnrB, qnrS, aac(6')-lb-cr, qepA and oqxAB) was done using monoplex and duplex PCR. Twenty-five ESBL-producing and FQEC were obtained from the cattle (6), piggery (7) and poultry (12) waste dumps of the farm. There was 100% resistance to cefpodoxime, cefotaxime, enrofloxacin, trimethoprim-sulfamethoxazole and penicillin by the isolates. The resistance to the other antibiotics was streptomycin (48%), ceftazidime (24%), while no isolate resisted amoxicillin-clavulanate and imipenem. The frequencies of PMQR genes detected were; qnrA (96%), oqxAB (96%), qnrB (92%), while  qnrS was detected in 88% (22) of the isolates. Aminoglycoside acetyltransferase (aac(6')-lb-cr) and quinolone efflux pump (qepA) were each detected in 20 (80%) of the isolates. CONCLUSIONS: This study showed that animal wastes disposed indiscriminately into dumps could be a budding 'hotspot' for multidrug resistant, ESBL-producing and fluoroquinolone-resistant E. coli carrying multiple genes encoding resistance to fluoroquinolone antibiotics.

Nigella sativa oil protects against cadmium-induced intestinal toxicity via promotion of anti-inflammatory mechanisms, mucin expression and microbiota integrity.

Objective: This study examined the protective effects of Nigella sativa oil (NSO) on cadmium (Cd)-induced alterations affecting gut morphology and microbiota composition, as well as the involvement of mucus glycoprotein (MUC2) and immuno-inflammatory markers (TNFα and IL-2) in the colon of rats. Materials and Methods: Male Wistar rats, randomized into four groups, were treated either with distilled water (control), CdCl2 (100 mg/kg), CdCl2+NSO (1 ml/kg) or NSO alone. After the experiments, faecal samples were processed for microbial culture on various selective media, while intestinal segments were prepared for histopathological examination and immunohistochemistry. The composition of NSO was analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). Results: Oral Cd administration provoked dramatic increases in faecal counts of potentially pathogenic bacteria (Staphylococci, Enterococci, Pseudomonas and Escherichia coli), while decreasing probiotic lactobacilli counts. Cadmium treatment caused down-regulation of colonic MUC2 (p=0.003) and IL-2 (p=0.03), but increased TNFα (p=0.034), along with reduced goblet cell counts and mucus production. Conversely, treatment with NSO significantly improved Lactobacilli counts (p=0.042), while reducing the levels of potentially pathogenic species. In addition, NSO significantly restored colonic expressions of MUC2 (p=0.001), TNFα (p=0.007) and IL-2 (p=0.025) to control levels. GC-MS analysis of NSO revealed the presence of the active ingredient, thymoquinone and a high content of unsaturated fatty acids, including trans-13-octadecenoic acid and oleic acid. Conclusion: This study highlights the intestinal mucus, microbiota and immuno-inflammatory system as important protective targets of NSO against Cd-induced intestinal toxicity.

High burden of ESBL- producing Klebsiella spp., Proteus mirabilis, Enterobacter cloacae and Pseudomonas aeruginosa in diagnosed cases of urinary tract infection in a Nigerian Teaching Hospital.

Infections of the urinary tract have been on the rise globally and these are also worsened by the increasing rate of antibiotic resistance in uropathogens. This study aimed to determine the susceptibility profile of extended spectrum ß-lactamase (ESBL)- producing uropathogens to selected antibiotics and their carriage of ESBL genes. Bacterial uropathogens were obtained from the urine bench of a Microbiology laboratory in a Teaching Hospital in South-West Nigeria. Susceptibility to antibiotics was tested using the disc diffusion method, while detection of ESBL production was done using the double disc synergy test (DDST). Detection of ESBL genes was performed by PCR. A total of 21 ESBL- producing uropathogens were obtained namely: Klebsiella pneumoniae (11), Klebsiella oxytoca (6), Proteus mirabilis (2), Enterobacter cloacae (1) and Pseudomonas aeruginosa (1). The resistance to antibiotics in the uropathogens was: imipenem (0%), gentamicin (38.1%), sulfamethoxazole-trimethoprim (52.4%), amoxicillin-clavulanate (61.9%), aztreonam (66.7%), ceftazidime (66.7%), tetracycline (90.5%), cefpodoxime (100%) and cefotaxime (100%). Altogether, 90.5% (19/21) of the isolates were multidrug resistant (MDR). Of the 21 uropathogens, 61.9% (13/21) carried bla CTX-M, 52.4% (11/21) carried bla TEM while bla SHV was detected in 47.6% (10/21) of the isolates. There was co-carriage of ESBL genes in 12 uropathogens. This study showed a high prevalence of multidrug resistance and a high carriage of ESBL genes in the ESBL- producing isolates obtained over the study period. There is a need for a review of antibiotic options in the treatment of UTI to clamp down on the ever-increasing tide of antibiotic resistance in uropathogens.

High carriage of plasmid-mediated quinolone resistance (PMQR) genes by cefotaxime-resistant Escherichia coli recovered from surface-leaking sanitary sewers.

There is a rapid rise in the incidence of quinolone resistant bacteria in Nigeria. Most studies in Nigeria have focused on isolates from the clinical settings, with few focusing on isolates of environmental origin. This study aimed to investigate the antibiogram and carriage of plasmid-mediated quinolone resistance (PMQR) genes by quinolone-resistant isolates obtained from a pool of cefotaxime-resistant Escherichia coli (E. coli) recovered from sewage leaking out of some surface-leaking sanitary sewers in a University community in Nigeria. Isolation of E. coli from the sewage samples was done on CHROMagar E. coli, after enrichment of the samples was done in Brain Heart Infusion broth amended with 6 µg/mL of cefotaxime. Identification of presumptive E. coli was done using molecular methods (detection of uidA gene), while susceptibility to antibiotics was carried out using the disc diffusion method. Detection of PMQR genes (qnrA, qnrB, qnrS, aac(6')-lb-cr, qepA and oqxAB) was carried out using primer-specific PCR. A total of 32 non-repetitive cefotaxime-resistant E. coli were obtained from the sewage, with 21 being quinolone-resistant. The quinolone-resistant isolates showed varying level of resistance to the tested antibiotics, with imipenem being the only exception with 0% resistance. The PMQR genes: aac(6')-lb-cr, qnrA, qnrB, qnrS and qepA and oqxAB were detected in 90.5%, 61.9%, 47.6%, 38.1%, 4.8% and 0% respectively of the isolates. The findings of this study showed a high level of resistance to antibiotics and carriage of PMQR genes by quinolone-resistant E. coli obtained from the leaking sanitary sewers, suggesting a potential environmental and public health concern.

Treated wastewater suitability for reuse in comparison to groundwater and surface water in a peri-urban area: Implications for water quality management.

The climate change and population growth led to a severe water shortage that limits fresh water availability in some areas of Togo. Thus, the farmers of Adjougba District have no other choice than using treated wastewater as an alternative for irrigated agriculture. The purpose of this study is to compare the suitability of three types of water for uses with identification of the reliable parameters in the assessment of water suitability for irrigation and domestic purposes. The raw water quality parameters, water quality indices (WQIs) and water suitability indicators for irrigation purpose (WSI-IPs) were applied for the comparison while statistical analysis and, with some experts' consensus were used to identify reliable parameters. The results suggested that the treated wastewater is more suitable than groundwater for irrigation purpose. Treated wastewater constitutes a viable fertilizer supply and is placed like surface water from permissible to excellent classes according to WSI-IPs values. The sodium absorption ratio (SAR), electrical conductivity (EC), residual sodium carbonate (RSC), Cl- and faecal coliforms (FC) are the most reliable parameters in the detection of water suitability for irrigation purpose. EC, DO, pH, turbidity or TSS, COD or CODMn, hardness, FC, NO3-, national sanitation foundation's water quality index (NSFWQI), and overall index of pollution (OPI) are the most reliable in the detection of water suitability for domestic use. The reliable parameters identified in this study are potential candidates for the development of a single water quality index for both irrigation and domestic uses in Adjougba District. However further study will be necessary for the identification of reliable parameters and the development of a water quality index at the country scale.

Antibiotic resistance pattern and frequency of cagA and vacA genes in Helicobacter pylori strains isolated from patients in Tabriz city, Iran.

OBJECTIVE: Helicobacter pylori is one of the most common causes of gastric infections in humans. It is estimated that approximately 50% of people around the world are infected with this bacterium. This study aimed to determine the antibiotic resistance pattern, as well as the frequency of cagA and vacA genes in H. pylori isolates obtained from patients in the clinical centers in Tabriz city, Iran. RESULTS: The culture method detected 100 (45.25%) H. pylori isolates from 221 biopsy samples during 3 years. The results showed that 63% and 81% of the isolates were positive for cagA and vacA genes, respectively. The highest resistance of isolates was seen against metronidazole (79%) and amoxicillin (36%), respectively. Also, the isolates showed the least resistance to tetracycline (8%).

Molecular characterization of ESBL- producing uropathogenic Escherichia coli recovered from urine samples of patients attending a University Teaching hospital in Nigeria.

Infection of the urinary tract ranks as one of the most common infections affecting people worldwide and its treatment is made complicated by the rising incidence of antibiotic resistance. This study aimed to detect extended spectrum beta-lactamase (ESBL) genes and antibiotic resistance profile of uropathogenic Escherichia coli (E. coli) recovered from patients attending a University Teaching hospital in Nigeria. Uropathogenic E. coli isolates were obtained from the culture collection of Department of Microbiology and Parasitology of the University Teaching hospital for a period of four months (October 2019-January, 2020). Antibiotic susceptibility testing was done using the disc diffusion method while phenotypic ESBL production was detected using double disc synergy test (DDST). Detection of ß-lactamase genes was done using Real-Time PCR. Forty-nine E. coli isolates were recovered from 120 urine samples, with 24 (49%) being ESBL positive. The resistance to antibiotics in the ESBL producers was: ciprofloxacin (100%), cefotaxime (100%), cefpodoxime (100%), tetracycline (95.7%), ceftazidime (56.7%), amoxicillin-clavulanate (50%), gentamicin (33.3%), and imipenem (0%). All the ESBL producers carried blaTEM, blaCTX-M-1 and blaCTX-M-9, 75% (18/24) carried blaSHV, while blaCTX-M-2, blaCTX-M-8 and blaCTX-M-25 groups were detected in 20.8% (5/24) of the isolates. There was co-occurrence of CTX-M, SHV and TEM ß-lactamases in 79.2% (19/24) isolates, while five isolates (20.8%) co-harbored blaCTX-M and blaTEM. This study showed a high level of multidrug resistance and ESBL gene carriage in uropathogenic E. coli obtained in this study, suggesting a likely review of therapeutic options in the treatment of UTI to clamp down on the rising cases of antibiotic resistance.