Antimicrobial resistance among bacteria isolated from urinary tract infections in females in Namibia, 2016-2017

Novel Fabrication of Bio-polymeric Nanogel Loaded with Nalidixic Acid Formulations for the Effective Prevention of Bacterial Pathogens Leading Urinary Tract Infection and Its Biosafety Evaluation

Management of urinary tract infections (UTI) is a highly challenging process due to the biofilm-forming ability of human-pathogenic bacteria. Here, we designed to fabricate an effective nanogel with a combination of chitosan bio-polymer and nalidixic acid to prevent biofilm-forming bacterial pathogens. Chitosan-coated nalidixic acid nanogel (NA@CS) exhibits outstanding inhibition potential against bacterial strains. In vitro, anti-bacterial analysis methods (well diffusion, colony-forming assay, and anti-biofilm assay) were performed to study the bacterial inhibition potential of prepared nanogel, which reveals that NA@CS nanogel have greater inhibition potential against selected pathogens. The combination of nalidixic acid with chitosan biopolymer decreases the virulence and pathogenicity of biofilm-forming pathogens due to their ability to membrane phospholipids penetration. Furthermore, the fabricated NA@CS nanogel showed reliable in vitro bio-compatibility on L929 fibroblast cells and in vivo compatibility with Artemia salina animal model. Overall, the results demonstrate that NA@CS nanogel could be an effective therapeutic for treating urinary tract infections and urine bladder wound healing.

The Importance of Carbapenemase-Producing Enterobacterales in African Countries: Evolution and Current Burden

Antimicrobial resistance (AMR) is a worldwide healthcare problem. Multidrug-resistant organisms (MDROs) can spread quickly owing to their resistance mechanisms. Although colonized individuals are crucial for MDRO dissemination, colonizing microbes can lead to symptomatic infections in carriers. Carbapenemase-producing Enterobacterales (CPE) are among the most important MDROs involved in colonizations and infections with severe outcomes. This review aimed to track down the first reports of CPE in Africa, describe their dissemination throughout African countries and summarize the current status of CRE and CPE data, highlighting current knowledge and limitations of reported data. Two database queries were undertaken using Medical Subject Headings (MeSH), employing relevant keywords to identify articles that had as their topics beta-lactamases, carbapenemases and carbapenem resistance pertaining to Africa or African regions and countries. The first information on CPE could be traced back to the mid-2000s, but data for many African countries were established after 2015-2018. Information is presented chronologically for each country. Although no clear conclusions could be drawn for some countries, it was observed that CPE infections and colonizations are present in most African countries and that carbapenem-resistance levels are rising. The most common CPE involved are Klebsiella pneumoniae and Escherichia coli, and the most prevalent carbapenemases are NDM-type and OXA-48-type enzymes. Prophylactic measures, such as screening, are required to combat this phenomenon.

A Case of Urinary Tract Infection Caused by Multidrug Resistant Streptococcus mitis/oralis

S. mitis/oralis has been previously reported in isolated cases of bacterial endocarditis and liver abscesses. Its presence in urine is generally considered a contaminant. A 66-year-old male patient was admitted to the hospital due to recurrent chest tightness and four-year history of exertional dyspnea. On the second day of admission, the patient presented with urgent and frequent urination, as well as dysuria. Both initial and subsequent urine cultures showed S. mitis/oralis infection, with polymorphonuclear leukocyte phagocytosis observed in the second sample. MALDI-TOF results confirmed the isolated strain as S. mitis/oralis. Drug susceptibility testing revealed multidrug resistance to penicillin, ceftriaxone, cefepime, levofloxacin, ofloxacin, and tetracycline, but sensitivity to quinupristin/dalfopristin, vancomycin, and linezolid. The clinician then prescribed vancomycin for anti-infective treatment, which proved effective. Keywords: S. mitis/oralis, UTI, MDR, phagocytosis.

Antimicrobial resistance prevalence of Escherichia coli and Staphylococcus aureus amongst bacteremic patients in Africa: a systematic review

OBJECTIVES

Antimicrobial resistance (AMR) is a global concern among infectious diseases. Bloodstream infections can potentially become life-threatening if they become untreatable with conventional antimicrobials. This review aims to provide an understanding of the AMR prevalence and trends of common bacteremic pathogens, namely Escherichia coli and Staphylococcus aureus in the World Health Organization (WHO) Africa region.

METHODS

PubMed and Google Scholar were searched using relevant keywords for published human studies (excluding case reports and reviews) reporting bacteremic AMR data on the pathogens of interest between 2008 and 2019. Two reviewers independently screened the articles against a pre-defined eligibility criterion. Data extraction and analysis were achieved with different platforms: Covidence, Excel, R version 3.6.3, and QGIS v3.4.5. The pooled prevalence, 95% confidence intervals, and I² index (a measure of heterogeneity) were calculated for the various pathogen-antibiotic combinations.

RESULTS

Five hundred sixty-two papers were retrieved, with 27 papers included in the final analysis. Only 23.4% (11/47) of member states of the WHO African region had reports on AMR in bacteremia. The Clinical and Laboratory Standards Institute (CLSI) (78.5%) was the most common standard used in the region. For E. coli, the pooled resistance was: cefotaxime (42%), imipenem (4%), meropenem (0%), and colistin (0%). For S. aureus, the calculated pooled resistance was cloxacillin (34%), oxacillin (12%), and vancomycin (0%). There was a high degree of variation across studies (I² > 90%).

CONCLUSION

The pooled resistance rates indicate a concerning degree of methicillin-resistant and Extended Spectrum-ß-lactamase-producing pathogens. The paucity of AMR data also presents challenges for a comprehensive understanding of the situation in the region. Continent-wide and standardized surveillance efforts therefore need strengthening.

Isolation and drug susceptibility pattern of uropathogens in Saudi diabetic and non-diabetic patients with urinary tract infection

Urinary tract infection (UTI), contribute substantially to healthcare burden. Diabetes predispose to UTI with high glycosuria being fertile medium for bacterial growth. With changing bacterial drug resistance patterns; the problem needs to be studied periodically to ensure a rational therapy, minimize adverse effects, and cost. Therefore, it is of interest to compare the profile and susceptibility pattern of uropathogens isolated from diabetic and non-diabetic patients with UTI. Mid-stream urine samples of 1100 patients (diabetic and non-diabetic), presenting with UTI symptoms were aseptically collected and inoculated into CLED medium. Colony counts of 105cfu/ml or 104cfu/ml and >5 pus cells per high power microscopic field were regarded as significant bacteriuria. Colonies from CLED were sub-cultured onto sheep blood agar and MacConkey agar. Bacterial identification was performed on the basis of colony morphology, gram staining, and series of biochemical tests though Analytical Profile Index (API) test strips. Drug susceptibility was done by standard Kirby-Bauer disk diffusion. Data was analyzed by SPSS ver. 25.Clinically significant bacteriuria was 32.8% and 19.2% in diabetics and non-diabetics respectively. The frequency of male and female patients was 153 and 208 in diabetic group; and 69 and 142 respectively in non-diabetic group. Diabetics were twice at risk of UTI; [Odds ratio; 2.04 (CI: 1.68-2.48, p<0.05)]. .Escherichia coli and klebsiella were most common gram-negative, while Staphylococcus aureus and Coagulase-negative staphylococci (CoNS) were most common gram-positive bacteria in both the groups. Most effective antibiotics against gram-negative bacteria were carbapenems, amikacin, colistin, and piperacillin/tazobactam; while ampicillin/amoxicillin, fluoroquinolones and cephalexin were least effective. For gram-positives, vancomycin, linezolid and tigecycline were most effective. No significant difference in bacterial profile and susceptibility pattern was found between diabetics and non-diabetics. However, diabetics were twice at risk of UTI compared to non-diabetics.

Analysis of policies for use of medically important antibiotics in animals in Namibia: implications for antimicrobial stewardship

BACKGROUND

In Namibia, overuse of medically important antibiotics in animals is common and is a considerable driver of antimicrobial resistance. The study aims to analyze policies, resistance patterns and consumption of these antibiotics used in animals in Namibia.

RESEARCH DESIGN AND METHODS

A scoping review and retrospective descriptive analysis of policies, resistance patterns and use of these antibiotics in Namibia was conducted, and assessed against the AWaRe (Access, Watch and Reserve) antimicrobial use guidance.

RESULTS

Of the forty-five antibiotic products registered for use in animals, 77.8% are Access antibiotics, 68.9% are broad-spectrum and 60% are over-the-counter antibiotics- mainly tetracyclines, penicillins and sulfonamides. There is misalignment of antibiotic use policies for animals and humans and no guideline for antibiotic use in animals. Most medically important antibiotics are indicated for control of gastrointestinal (77.7%), musculoskeletal (71.1%) and respiratory (46.7%) infections, and for growth promotion (4.4%). There is high resistance to AWaRe Access antibiotics- sulfonamides (19.5%-100%), tetracyclines (56%-100%) and penicillin (13.5%-100%).

CONCLUSION

Whilst Namibia banned the use of antibiotics in farming, current policy frameworks are inconsistent across sectors, and promote overuse of broad-spectrum important antibiotics in animals. A multi-sectoral one health approach is required to harmonize antibiotic use policies and reduce resistance.