Evaluation of three protocols for direct susceptibility testing for gram negative-Enterobacteriaceae from patient samples in Uganda with SMS reporting.

In Uganda, the challenge of generating and timely reporting essential antimicrobial resistance (AMR) data has led to overreliance on empirical antibiotic therapy, exacerbating the AMR crisis. To address this issue, this study aimed to adapt a one-step AMR testing protocol alongside an SMS (Short Message Service) result relay system (SRRS), with the potential to reduce the turnaround time for AMR testing and result communication from 4 days or more to 1 day in Ugandan clinical microbiology laboratories. Out of the 377 samples examined, 54 isolates were obtained. Notably, E. coli (61%) and K. pneumoniae (33%) were the most frequently identified, majority testing positive for ESBL. Evaluation of three AMR testing protocols revealed varying sensitivity and specificity, with Protocol A (ChromID ESBL-based) demonstrating high sensitivity (100%) but no calculable specificity, Protocol B (ceftazidime-based) showing high sensitivity (100%) and relatively low specificity (7.1%), and Protocol C (cefotaxime-based) exhibiting high sensitivity (97.8%) but no calculable specificity. ESBL positivity strongly correlated with resistance to specific antibiotics, including cefotaxime, ampicillin, and aztreonam (100%), cefuroxime (96%), ceftriaxone (93%), and trimethoprim sulfamethoxazole (87%). The potential of integrating an SRRS underscored the crucial role this could have in enabling efficient healthcare communication in AMR management. This study underscores the substantial potential of the tested protocols for accurately detecting ESBL production in clinical samples, potentially, providing a critical foundation for predicting and reporting AMR patterns. Although considerations related to specificity warrant careful assessment before widespread clinical adoption.

Adherence to malaria treatment guidelines among health care workers in private health facilities in Kampala's informal settlements, Uganda.

Poor adherence to malaria treatment guidelines among healthcare workers (HCWs) is a major contribution to diagnostic challenges, treatment failure, and non-rational use of antimalarial medicines. However, there is limited information about adherence to malaria treatment guidelines among HCWs in private health facilities in informal settlements in Uganda. This study therefore assessed the level of adherence to malaria treatment guidelines and associated factors among HCWs in private health facilities in Kampala's informal settlements. A cross-sectional study was conducted among 339 HCWs from private health facilities in slums of 4 selected divisions in Kampala, Uganda. Quantitative data was collected using a semi-structured questionnaire, cleaned in MS Excel 2016 and analyzed using STATA 15.0 statistical software. Bivariate and multivariate analysis were conducted using a generalized linear model of modified Poisson regression to obtain factors associated with adherence to malaria treatment guidelines. The study revealed that majority of respondents 71.1%(241/339) were aged 30 years and below, and 50.1%(170/339) of the were female. Almost all of the respondents 98.8%(335/339) reported that they had malaria diagnostic equipment (microscopy or rapid diagnostic tests) at their facilities, 47.5%(161/339) had non-recommended anti-malarial drugs present in stock and 36.0% reported that they did not refer severely ill patients to higher health facilities in the previous 3 months. Although 92.6%(314/339) of the respondents had heard about the national malaria treatment guidelines, 63.1%(214/339) of them adhered to these guidelines. Having a bachelors degree (APR 1.54, (CI: 1.13-2.10)P 0.006), and having high levels of knowledge (APR 1.44, (CI: 1.13-1.60)P 0.001) were positively associated with high adherence to malaria treatment guidelines. In conclusion, adherence to malaria treatment guidelines was suboptimal and less than the national target of 90%. Enforcement, supervision, trainings, and continuous medical education should be enhanced in private healthcare facilities to improve adherence to malaria treatment guidelines in informal settlements.

Isoniazid preventive therapy completion and factors associated with non-completion among patients on antiretroviral therapy at Kisenyi Health Centre IV, Kampala, Uganda.

BACKGROUND: Isoniazid preventive therapy (IPT) is given to HIV patients to reduce the risk of active tuberculosis (TB). However, treatment completion remains suboptimal among those that are initiated. This study aimed to determine the completion level of IPT and the factors associated with non-completion among patients on antiretroviral therapy (ART) at Kisenyi Health Center IV in Kampala, Uganda. METHODS: A mixed-methods facility-based retrospective cohort study utilizing routinely collected data from 341 randomly selected HIV patients initiated on IPT was conducted. Data extracted from the registers was used to determine IPT completion. Robust Poisson regression was conducted to determine the associated factors of IPT non-completion, while in-depth interviews were conducted to explore barriers to IPT completion from the patient's perspective. RESULTS: A total of 341 patients who started on isoniazid (INH) were retrospectively followed up, with 69% (236/341) being female. Overall IPT completion was 83%. Multivariate analysis revealed the prevalence of IPT non-completion among males was 2.24 times the prevalence among females (aPR 2.24, 95% CI: 1.40-3.58, p = 0.001). The prevalence of IPT non-completion among patients with a non-suppressed HIV viral load was 3.00 times the prevalence among those with a suppressed HIV viral load (aPR 3.00, 95% CI: 1.44-6.65, p = 0.007). The prevalence of IPT non-completion among patients who were married, or cohabiting was 0.31 times the prevalence among those who were single (aPR 0.31, 95% CI: 0.17-0.55, p<0.000). Lack of IPT-related health education, pill burden, distance to the health facility, and patient relocation were reported as barriers to IPT completion. CONCLUSION: IPT completion was found to be 83% among the cohort studied. However, lower completion levels persist among males and HIV-virally non-suppressed patients. Lack of IPT-related health education, pill burden, distance to the health facility, and patient relocation were reported as barriers to IPT completion. Interventions that target these groups of people need to be intensified.

Investigating the evolution and predicting the future outlook of antimicrobial resistance in sub-saharan Africa using phenotypic data for Klebsiella pneumoniae: a 12-year analysis.

BACKGROUND: Antimicrobial resistance (AMR) is a major public health challenge, particularly in sub-Saharan Africa (SSA). This study aimed to investigate the evolution and predict the future outlook of AMR in SSA over a 12-year period. By analysing the trends and patterns of AMR, the study sought to enhance our understanding of this pressing issue in the region and provide valuable insights for effective interventions and control measures to mitigate the impact of AMR on public health in SSA. RESULTS: The study found that general medicine patients had the highest proportion of samples with AMR. Different types of samples showed varying levels of AMR. Across the studied locations, the highest resistance was consistently observed against ceftaroline (ranging from 68 to 84%), while the lowest resistance was consistently observed against ceftazidime avibactam, imipenem, meropenem, and meropenem vaborbactam (ranging from 92 to 93%). Notably, the predictive analysis showed a significant increasing trend in resistance to amoxicillin-clavulanate, cefepime, ceftazidime, ceftaroline, imipenem, meropenem, piperacillin-tazobactam, and aztreonam over time. CONCLUSIONS: These findings suggest the need for coordinated efforts and interventions to control and prevent the spread of AMR in SSA. Targeted surveillance based on local resistance patterns, sample types, and patient populations is crucial for effective monitoring and control of AMR. The study also highlights the urgent need for action, including judicious use of antibiotics and the development of alternative treatment options to combat the growing problem of AMR in SSA.

Source-tracking ESBL-producing bacteria at the maternity ward of Mulago hospital, Uganda.

INTRODUCTION: Escherichia coli, Klebsiella pneumoniae and Enterobacter (EKE) are the leading cause of mortality and morbidity in neonates in Africa. The management of EKE infections remains challenging given the global emergence of carbapenem resistance in Gram-negative bacteria. This study aimed to investigate the source of EKE organisms for neonates in the maternity environment of a national referral hospital in Uganda, by examining the phenotypic and molecular characteristics of isolates from mothers, neonates, and maternity ward. METHODS: From August 2015 to August 2016, we conducted a cross-sectional study of pregnant women admitted for elective surgical delivery at Mulago hospital in Kampala, Uganda; we sampled (nose, armpit, groin) 137 pregnant women and their newborns (n = 137), as well as health workers (n = 67) and inanimate objects (n = 70 -beds, ventilator tubes, sinks, toilets, door-handles) in the maternity ward. Samples (swabs) were cultured for growth of EKE bacteria and isolates phenotypically/molecularly investigated for antibiotic sensitivity, as well as ß-lactamase and carbapenemase activity. To infer relationships among the EKE isolates, spatial cluster analysis of phenotypic and genotypic susceptibility characteristics was done using the Ridom server. RESULTS: Gram-negative bacteria were isolated from 21 mothers (15%), 15 neonates (11%), 2 health workers (3%), and 13 inanimate objects (19%); a total of 131 Gram-negative isolates were identified of which 104 were EKE bacteria i.e., 23 (22%) E. coli, 50 (48%) K. pneumoniae, and 31 (30%) Enterobacter. Carbapenems were the most effective antibiotics as 89% (93/104) of the isolates were susceptible to meropenem; however, multidrug resistance was prevalent i.e., 61% (63/104). Furthermore, carbapenemase production and carbapenemase gene prevalence were low; 10% (10/104) and 6% (6/104), respectively. Extended spectrum ß-lactamase (ESBL) production occurred in 37 (36%) isolates though 61 (59%) carried ESBL-encoding genes, mainly blaCTX-M (93%, 57/61) implying that blaCTX-M is the ideal gene for tracking ESBL-mediated resistance at Mulago. Additionally, spatial cluster analysis revealed isolates from mothers, new-borns, health workers, and environment with similar phenotypic/genotypic characteristics, suggesting transmission of multidrug-resistant EKE to new-borns. CONCLUSION: Our study shows evidence of transmission of drug resistant EKE bacteria in the maternity ward of Mulago hospital, and the dynamics in the ward are more likely to be responsible for transmission but not individual mother characteristics. The high prevalence of drug resistance genes highlights the need for more effective infection prevention/control measures and antimicrobial stewardship programs to reduce spread of drug-resistant bacteria in the hospital, and improve patient outcomes.

Medically important bacteria isolated from commercial herbal medicines in Kampala city indicate the need to enhance safety frameworks.

The high global bacterial infection burden has created need to investigate the neglected potential drivers of pathogenic bacteria, to inform disease prevention. Kampala is facing a proliferation of herbalists, selling herbal medicine (HM), of largely unregulated microbiological quality. We evaluated the bacterial contamination burden in HM sold in Kampala, to support evidence-based redress. The total viable loads (TVL), total coliform counts (TCC), E. coli counts, and prevalence of selected bacterial strains in 140 HM were examined using conventional culture, following the guidelines of World Health Organization (WHO), and Uganda National Drug Authority (NDA). Data were analyzed using D'Agostino-Pearson test, frequencies, proportions, Chi-square, and Mann-Whitney U test with STATA version-15.0. Fifty (35.7%), fifty-nine (42.1%), and twelve (8.6%) HM were unsafe for human use because they exceeded WHO's permissible limits for TVL, TCC, and E. coli counts respectively. Solids had significantly higher mean TVL than liquids. Violation of NDA's guidelines was significantly associated with high TVL. Fifty-nine bacteria, viz., Klebsiella pneumoniae (n = 34; 57.6%), Escherichia. coli (12; 20.3%), Staphylococcus aureus (7; 11.9%), Klebsiella oxytoca (3; 5.1%), Bacillus cereus, Pseudomonas aeruginosa, and Enterobacter spp. (1; 1.7% each), were isolated from 45 (32.1%) samples. These bacteria can cause severe clinical diseases, and promote deterioration of HM potency.

The need to improve antimicrobial susceptibility testing capacity in Ugandan health facilities: insights from a surveillance primer.

BACKGROUND: Lab-based surveillance (LBS) of antimicrobial resistance (AMR) is not systematically implemented in Uganda. We aimed to identify the gaps in establishing regular LBS of AMR in Uganda. METHODS: This was a retrospective records review. It was done at Mulago Hospital (MH) Microbiology Lab (MHL). It analyzed lab records on bacteria and their antimicrobial susceptibility profiles (ASPs) over 6 months. Since MH is the national referral hospital, we hypothesized that (1) MHL is the best resourced and that any limitations seen here are amplified in labs at regional referral hospitals (RRHs) and health centers (HCs); (2) data from MHL on LBS mirrors that from labs at RRHs and HCs; (3) the state of records from MHL show lab performance and the presence or absence of standard operating procedures (SOPs), as would be the case at RRHs and HCs. RESULTS: The lab got 1760 samples over the six months. The most common sample was urine (659, 37.4%). From the 1760 samples, data on 478 bacterial isolates were available. Urine gave the most isolates (159, 33.3%). Most of the isolates were gram-negative (267, 55.9%). Escherichia coli (100, 37%) was the most common gram-negative (of the Enterobacteriaceae). Pseudomonas aeruginosa (17, 6%) was the most common gram-negative (of the non-Enterobacteriaceae). The gram-negative bacteria were highly resistant to ß-lactams. These were highly sensitive to carbapenems. The Staphylococcus aureus were highly resistant to ß-lactams. The gram-positive bacteria were highly sensitive to vancomycin. ASPs for all bacterial categories were incomplete. CONCLUSIONS: The findings from MHL suggest that there is a need to improve antimicrobial susceptibility testing capacity. They also suggest that the situation at RRHs and HCs around the country could be worse. So, there is a need to extend the political will, which already exists, into operational and implementation action.

Antibiotic-resistance in medically important bacteria isolated from commercial herbal medicines in Africa from 2000 to 2021: a systematic review and meta-analysis.

BACKGROUND: Antimicrobial resistance is swiftly increasing all over the world. In Africa, it manifests more in pathogenic bacteria in form of antibiotic resistance (ABR). On this continent, bacterial contamination of commonly used herbal medicine (HM) is on the increase, but information about antimicrobial resistance in these contaminants is limited due to fragmented studies. Here, we analyzed research that characterized ABR in pathogenic bacteria isolated from HM in Africa since 2000; to generate a comprehensive understanding of the drug-resistant bacterial contamination burden in this region. METHODS: The study was conducted according to standards of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). We searched for articles from 12 databases. These were: PubMed, Science Direct, Scifinder scholar, Google scholar, HerbMed, Medline, EMBASE, Cochrane Library, International Pharmaceutical Abstracts, Commonwealth Agricultural Bureau Abstracts, African Journal Online, and Biological Abstracts. Prevalence and ABR traits of bacterial isolates, Cochran's Q test, and the I2 statistic for heterogeneity were evaluated using MedCalcs software. A random-effects model was used to determine the pooled prevalence of ABR traits. The potential sources of heterogeneity were examined through sensitivity analysis, subgroup analysis, and meta-regression at a 95% level of significance. FINDINGS: Eighteen studies met our inclusion criteria. The pooled prevalence of bacterial resistance to at least one conventional drug was 86.51% (95% CI = 61.247-99.357%). The studies were highly heterogeneous (I2 = 99.17%; p < 0.0001), with no evidence of publication bias. The most prevalent multidrug-resistant species was Escherichia coli (24.0%). The most highly resisted drug was Ceftazidime with a pooled prevalence of 95.10% (95% CI = 78.51-99.87%), while the drug-class was 3rd generation cephalosporins; 91.64% (95% CI = 78.64-96.73%). None of the eligible studies tested isolates for Carbapenem resistance. Extended Spectrum ß-lactamase genes were detected in 89 (37.2%) isolates, mostly Salmonella spp., Proteus vulgaris, and K. pneumonia. Resistance plasmids were found in 6 (5.8%) isolates; the heaviest plasmid weighed 23,130 Kilobases, and Proteus vulgaris harbored the majority (n = 5; 83.3%). CONCLUSIONS: Herbal medicines in Africa harbor bacterial contaminants which are highly resistant to conventional medicines. This points to a potential treatment failure when these contaminants are involved in diseases causation. More research on this subject is recommended, to fill the evidence gaps and support the formation of collaborative quality control mechanisms for the herbal medicine industry in Africa.

Transmission Dynamics of Antimicrobial Resistance at a National Referral Hospital in Uganda.

Reliable data on antimicrobial resistance (AMR) transmission dynamics in Uganda remains scarce; hence, we studied this area. Eighty-six index patients and "others" were recruited. Index patients were those who had been admitted to the orthopedic ward of Mulago National Referral Hospital during the study period; "others" included medical and non-medical caretakers of the index patients, and index patients' immediate admitted hospital neighbors. Others were recruited only when index patients became positive for carrying antimicrobial-resistant bacteria (ARB) during their hospital stay. A total of 149 samples, including those from the inanimate environment, were analyzed microbiologically for ARB, and ARB were analyzed for their antimicrobial susceptibility profiles and mechanisms underlying observed resistances. We describe the diagnostic accuracy of the extended-spectrum ß-lactamase (ESBL) production screening method, and AMR acquisition and transmission dynamics. Index patients were mostly carriers of ESBL-producing Enterobacteriaceae (PE) on admission, whereas non-ESBL-PE carriers on admission (61%) became carriers after 48 hours of admission (9%). The majority of ESBL-PE carriers on admission (56%) were referrals or transfers from other health-care facilities. Only 1 of 46 samples from the environment isolated an ESBL-PE. Marked resistance (> 90%) to ß-lactams and folate-pathway inhibitors were observed. The ESBL screening method's sensitivity, specificity, positive predictive value, and negative predictive value were 100%, 50%, 90%, and 100%, respectively. AMR acquisition and transmission occurs via human-human interfaces within and outside of health-care facilities compared with human-inanimate environment interfaces. However, this remains subject to further research.

Increasing Antimicrobial Resistance in Surgical Wards at Mulago National Referral Hospital, Uganda, from 2014 to 2018-Cause for Concern?

Antimicrobial Resistance (AMR) and Healthcare Associated Infections (HAIs) are major global public health challenges in our time. This study provides a broader and updated overview of AMR trends in surgical wards of Mulago National Referral Hospital (MNRH) between 2014 and 2018. Laboratory data on the antimicrobial susceptibility profiles of bacterial isolates from 428 patient samples were available. The most common samples were as follows: tracheal aspirates (36.5%), pus swabs (28.0%), and blood (20.6%). Klebsiella (21.7%), Acinetobacter (17.5%), and Staphylococcus species (12.4%) were the most common isolates. The resistance patterns for different antimicrobials were: penicillins (40-100%), cephalosporins (30-100%), ß-lactamase inhibitor combinations (70-100%), carbapenems (10-100%), polymyxin E (0-7%), aminoglycosides (50-100%), sulphonamides (80-100%), fluoroquinolones (40-70%), macrolides (40-100%), lincosamides (10-45%), phenicols (40-70%), nitrofurans (0-25%), and glycopeptide (0-20%). This study demonstrated a sustained increase in resistance among the most commonly used antibiotics in Uganda over the five-year study period. It implies ongoing hospital-based monitoring and surveillance of AMR patterns are needed to inform antibiotic prescribing, and to contribute to national and global AMR profiles. It also suggests continued emphasis on infection prevention and control practices (IPC), including antibiotic stewardship. Ultimately, laboratory capacity for timely bacteriological culture and sensitivity testing will provide a rational choice of antibiotics for HAI.

Gastrointestinal Tract Colonization Rate of Extended-Spectrum Beta-Lactamase-Producing Gram-Negative Bacteria and Associated Factors Among Orthopaedic Patients in a Tertiary Hospital in Tanzania: Implications for Infection Prevention.

BACKGROUND: The dual burden of road traffic accidents and antimicrobial resistance in orthopaedic infections is challenging already strained health-care systems. Limited information exists in Tanzania on antimicrobial resistance surveillance to delineate the potential sources of multi-drug-resistant bacteria for specific mitigation strategies among orthopaedic patients. METHODS: A longitudinal study was conducted at Bugando Medical Centre in Mwanza city between January and May 2020. It involved the collection of rectal swabs/stools, hand swabs, and environmental sampling to identify extended-spectrum beta-lactamase (ESBL)-producing gram-negative bacteria. Participants' data were collected using a structured questionnaire and analysed to determine factors associated with ESBL colonization among index orthopaedic patients and correlates with other ESBL sources using OR (95% CI) and a cut-off p-value of ≤0.05. RESULTS: We found that 47.2% (125/265) of index patients, 77.8% (14/18) of neighbouring patients, 8.3% (2/24) of health-care workers, 72.2% (13/18) of non-medical caregivers, and 31.4% (27/86) of samples taken from the hospital environment had ESBL producers. Escherichia coli and Klebsiella spp. predominated among participants and Acinetobacter spp. predominated in the environmental samples. Patients with open fractures had increased odds of being colonized with ESBL producers [OR (95% CI): 2.08 (1.16-3.75); p=0.015]. The floor below patients' beds was commonly contaminated; however, the odds of environmental contamination decreased on the third round of sampling [OR (95% CI: 0.16 (0.04-0.67); p=0.012], apparently as a result of parallel infection prevention and control responsive measures against coronavirus disease 2019 (COVID-19). CONCLUSION: We found a high occurrence of ESBL colonization among participants and in the environmentat this tertiary hospital. The importance of routine ESBL surveillance among orthopaedic patients with open fractures on admission and strengthened decontamination of health-care premises is reiterated.

Efficacy of Face Masks Used in Uganda: A Laboratory-Based Inquiry during the COVID-19 Pandemic.

With shortages of face masks being reported worldwide, it is critical to consider alternatives to commercially manufactured face masks. This study aimed to test and compare the efficacy of various makes of locally made or homemade cloth face masks obtained from face-mask vendors in Kampala, Uganda, during the COVID-19 pandemic. The testing was performed to assess the bacterial filtration efficiency (BFE), breathability, distance-dependent fitness, and reusability of the locally made or homemade cloth face masks, while considering the most commonly used non-published face-mask decontamination approaches in Uganda. During laboratory experimentation, modified protocols from various face-mask testing organizations were adopted. Ten different face-mask types were experimented upon; each face-mask type was tested four times for every single test, except for the decontamination protocols involving washing where KN95 and surgical face masks were not included. Among the locally made or homemade cloth face masks, the double-layered cloth face masks (described as F) had better BFE and distance-dependent fitness characteristics, they could be reused, and had good breathability, than the other locally made or homemade cloth face masks. Despite these good qualities, the certainty of these face masks protecting wearers against COVID-19 remains subject to viral filtration efficiency testing.

Genomics and bioinformatics capacity in Africa: no continent is left behind.

Despite the poor genomics research capacity in Africa, efforts have been made to empower African scientists to get involved in genomics research, particularly that involving African populations. As part of the Human Heredity and Health in Africa (H3Africa) Consortium, an initiative was set to make genomics research in Africa an African endeavor and was developed through funding from the United States' National Institutes of Health Common Fund and the Wellcome Trust. H3Africa is intended to encourage a contemporary research approach by African investigators and to stimulate the study of genomic and environmental determinants of common diseases. The goal of these endeavors is to improve the health of African populations. To build capacity for bioinformatics and genomics research, organizations such as the African Society for Bioinformatics and Computational Biology have been established. In this article, we discuss the current status of the bioinformatics infrastructure in Africa as well as the training challenges and opportunities.

Face-Masking, an Acceptable Protective Measure against COVID-19 in Ugandan High-Risk Groups.

Face-masking could reduce the risk of COVID-19 transmission. We assessed knowledge, attitudes, perceptions, and practices toward COVID-19 and face-mask use among 644 high-risk individuals in Kampala, Uganda. In data analysis, descriptive, bivariate, and multivariate logistic regression analyses with a 95% CI were considered. Adjusted odds ratios were used to determine the magnitude of associations. P-values < 0.05 were considered statistically significant. The majority, 99.7% and 87.3% of the participants, respectively, had heard about COVID-19 and believed that face-masks were protective against COVID-19, whereas 67.9% reported having received information on face-mask use. Food-market vendors and those with no formal education were 0.5 and 0.3 times less likely to have received information about face-mask use than hospital workers and those who had completed secondary school, respectively. Those who had received information on face-mask use were 2.9 and 1.8 times more likely to own face-masks and to perceive them as protective, respectively. Food-market vendors were 3.9 times more likely to reuse their face-masks than hospital workers. Our findings suggest that Ugandan high-risk groups have good knowledge, optimistic attitudes and perceptions, and relatively appropriate practices toward COVID-19.

Review of phenotypic assays for detection of extended-spectrum ß-lactamases and carbapenemases: a microbiology laboratory bench guide.

BACKGROUND: Infections caused by gram-negative antibiotic-resistant bacteria continue to increase. Despite recommendations by the Clinical Laboratory Standards Institute (CLSI) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) with regards to detection of antibiotic degrading enzymes secreted by these bacteria, the true prevalence of extended-spectrum ß-lactamase (ESBL) and carbapenemase producers remains a difficult task to resolve. Describing of previously designed phenotypic detection assays for ESBLs and carbapenemases in a single document avails a summary that allows for multiple testing which increases the sensitivity and specificity of detection. METHODS AND AIMS: This review, therefore, defined and classified ESBLs and carbapenemases, and also briefly described how the several previously designed phenotypic detection assays for the same should be performed. CONCLUSION: Extended-spectrum ß-lactamase and carbapenemase detection assays, once performed correctly, can precisely discriminate between bacteria producing these enzymes and those with other mechanisms of resistance to ß-lactam antibiotics.

blaVIM- and blaOXA-mediated carbapenem resistance among Acinetobacter baumannii and Pseudomonas aeruginosa isolates from the Mulago hospital intensive care unit in Kampala, Uganda.

BACKGROUND: Between January 2015 and July 2017, we investigated the frequency of carbapenem resistant Acinetobacter baumannii (CRAB) and carbapenem resistant Pseudomonas aeruginosa (CRPA) at the Mulago Hospital intensive care unit (ICU) in Kampala, Uganda. Carbapenemase production and carbapenemase gene carriage among CRAB and CRPA were determined; mobility potential of carbapenemase genes via horizontal gene transfer processes was also studied. METHODS: Clinical specimens from 9269 patients were processed for isolation of CRAB and CRPA. Drug susceptibility testing was performed with the disk diffusion method. Carriage of carbapenemase genes and class 1 integrons was determined by PCR. Conjugation experiments that involved blaVIM positive CRAB/CRPA (donors) and sodium azide resistant Escherichia coli J53 (recipient) were performed. RESULTS: The 9269 specimens processed yielded 1077 and 488 isolates of Acinetobacter baumannii and Pseudomonas aeruginosa, respectively. Of these, 2.7% (29/1077) and 7.4% (36/488) were confirmed to be CRAB and CRPA respectively, but 46 were available for analysis (21 CRAB and 25 CRPA). Majority of specimens yielding CRAB and CRPA were from the ICU (78%) while 20 and 2% were from the ENT (Ear Nose & Throat) Department and the Burns Unit, respectively. Carbapenemase assays performed with the MHT assay showed that 40 and 33% of CRPA and CRAB isolates respectively, were carbapenemase producers. Also, 72 and 48% of CRPA and CRAB isolates respectively, were metallo-beta-lactamase producers. All the carbapenemase producing isolates were multidrug resistant but susceptible to colistin. blaVIM was the most prevalent carbapenemase gene, and it was detected in all CRAB and CRPA isolates while blaOXA-23 and blaOXA-24 were detected in 29 and 24% of CRAB isolates, respectively. Co-carriage of blaOXA-23 and blaOXA-24 occurred in 14% of CRAB isolates. Moreover, 63% of the study isolates carried class 1 integrons; of these 31% successfully transferred blaVIM to E. coli J53. CONCLUSIONS: CRAB and CRPA prevalence at the Mulago Hospital ICU is relatively low but carbapenemase genes especially blaVIM and blaOXA-23 are prevalent among them. This requires strengthening of infection control practices to curb selection and transmission of these strains in the hospital.

Investigating colistin drug resistance: The role of high-throughput sequencing and bioinformatics.

Bacterial infections involving antibiotic-resistant gram-negative bacteria continue to increase and represent a major global public health concern. Resistance to antibiotics in these bacteria is mediated by chromosomal and/or acquired resistance mechanisms, these give rise to multi-drug resistant (MDR), extensive-drug resistant (XDR) or pan-drug resistant (PDR) bacterial strains. Most recently, plasmid-mediated resistance to colistin, an antibiotic that had been set apart as the last resort antibiotic in the treatment of infections involving MDR, XDR and PDR gram-negative bacteria has been reported. Plasmid-mediated colistin resistant gram-negative bacteria have been described to be PDR, implying a state devoid of alternative antibiotic therapeutic options. This review concisely describes the evolution of antibiotic resistance to plasmid-mediated colistin resistance and discusses the potential role of high-throughput sequencing technologies, genomics, and bioinformatics towards improving antibiotic resistance surveillance, the search for novel drug targets and precision antibiotic therapy focused at combating colistin resistance, and antibiotic resistance as a whole.