Antibiotic point prevalence survey and antimicrobial resistance in hospitalized patients across Peruvian reference hospitals

BACKGROUND

Peru reports higher levels than other countries in Latin America of resistance to antimicrobials among Gram-positive and Gram-negative bacteria, however data on antibiotic use in Peru are scarce. This study aims to estimate the prevalence and quality of antibiotic prescription in hospitalized patients and to determine the antibiotic susceptibility rates of bacteria causing key bacterial infections.

METHODS

We carried out a point prevalence survey of antibiotic prescription at ten public hospitals in nine regions of Peru. Data was collected from patients hospitalized during a 3-week period, with details about antibiotic use, patient information, and antimicrobial susceptibility.

RESULTS

1620 patient charts were reviewed; in 924 cases antibiotics were prescribed (57.0 %, range 45.9-78.9 %). Most of the antibiotics (74.2 %) were prescribed as empirical treatment, only 4.4 % as targeted treatment. For 9.5 % of cases the reason for antibiotic use was unknown. Cephalosporins were the most prescribed (30.0 %), followed by carbapenems (11.3 %). Ninety-four blood cultures were positive for bacterial growth, 48.8 % of the Staphylococcus aureus were methicillin-resistant, among Escherichia coli and Klebsiella pneumoniae, 51.7 % and 72.7 % were resistant to third-generation cephalosporins (3GC), 3.4 % and 18.2 % were resistant to carbapenems, respectively. Among bacteria isolated from urine cultures (n = 639), 43.9 % of E. coli and 49.2 % of K. pneumoniae were resistant to 3GC, and 0.9 % of E. coli and 3.2 % of K. pneumoniae were resistant to meropenem.

CONCLUSIONS

The overall proportion of hospitalized patients receiving antibiotics in hospitals from different regions in Peru was high, with only a small proportion receiving targeted treatment. Cephalosporins and carbapenems were the most frequently prescribed antibiotics, reflecting high resistance rates against 3GC and carbapenems in Enterobacterales isolated from blood and urine.

Methicillin-Resistant Staphylococcus aureus Bloodstream Infections in Hospitalized Patients in Peru

There is a knowledge gap in the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) causing bloodstream infections (BSIs) in Peru. Through a surveillance study in 13 hospitals of 10 Peruvian regions (2017-2019), we assessed the proportion of MRSA among S. aureus BSIs as well as the molecular typing of the isolates. A total of 166 S. aureus isolates were collected, and 36.1% of them were MRSA. Of note, MRSA isolates with phenotypic and genetic characteristics of the hospital-associated Chilean-Cordobes clone (multidrug-resistant SCCmec I, non-Panton-Valentine leukocidin [PVL] producers) were most commonly found (70%), five isolates with genetic characteristics of community-associated MRSA (CA-MRSA)-SCCmec IV, PVL-producer-(8.3%) were seen in three separate regions. These results demonstrate that hospital-associated MRSA is the most frequent MRSA found in patients with BSIs in Peru. They also show the emergence of S. aureus with genetic characteristics of CA-MRSA. Further studies are needed to evaluate the extension of CA-MRSA dissemination in Peru.

Prevalence of Antimicrobial Resistance in Gram-Negative Bacteria Bloodstream Infections in Peru and Associated Outcomes: VIRAPERU Study

Surveillance of antimicrobial resistance among gram-negative bacteria (GNB) is of critical importance, but data for Peru are not available. To fill this gap, a non-interventional hospital-based surveillance study was conducted in 15 hospitals across Peru from July 2017 to October 2019. Consecutive unique blood culture isolates of key GNB (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter spp.) recovered from hospitalized patients were collected for centralized antimicrobial susceptibility testing, along with linked epidemiological and clinical data. A total of 449 isolates were included in the analysis. Resistance to third-generation cephalosporins (3GCs) was present in 266 (59.2%) GNB isolates. Among E. coli (n = 199), 68.3% showed 3GC resistance (i.e., above the median ratio for low- and middle-income countries in 2020 for this sustainable development goal indicator). Carbapenem resistance was present in 74 (16.5%) GNB isolates, with wide variation among species (0% in E. coli, 11.0% in K. pneumoniae, 37.0% in P. aeruginosa, and 60.8% in Acinetobacter spp. isolates). Co-resistance to carbapenems and colistin was found in seven (1.6%) GNB isolates. Empiric treatment covered the causative GNB in 63.3% of 215 cases. The in-hospital case fatality ratio was 33.3% (92/276). Pseudomonas aeruginosa species and carbapenem resistance were associated with higher risk of in-hospital death. In conclusion, an important proportion of bloodstream infections in Peru are caused by highly resistant GNB and are associated with high in-hospital mortality.

The burden of antimicrobial resistance in the Americas in 2019: a cross-country systematic analysis

Background

Antimicrobial resistance (AMR) is an urgent global health challenge and a critical threat to modern health care. Quantifying its burden in the WHO Region of the Americas has been elusive-despite the region's long history of resistance surveillance. This study provides comprehensive estimates of AMR burden in the Americas to assess this growing health threat.

Methods

We estimated deaths and disability-adjusted life-years (DALYs) attributable to and associated with AMR for 23 bacterial pathogens and 88 pathogen-drug combinations for countries in the WHO Region of the Americas in 2019. We obtained data from mortality registries, surveillance systems, hospital systems, systematic literature reviews, and other sources, and applied predictive statistical modelling to produce estimates of AMR burden for all countries in the Americas. Five broad components were the backbone of our approach: the number of deaths where infection had a role, the proportion of infectious deaths attributable to a given infectious syndrome, the proportion of infectious syndrome deaths attributable to a given pathogen, the percentage of pathogens resistant to an antibiotic class, and the excess risk of mortality (or duration of an infection) associated with this resistance. We then used these components to estimate the disease burden by applying two counterfactual scenarios: deaths attributable to AMR (compared to an alternative scenario where resistant infections are replaced with susceptible ones), and deaths associated with AMR (compared to an alternative scenario where resistant infections would not occur at all). We generated 95% uncertainty intervals (UIs) for final estimates as the 25th and 975th ordered values across 1000 posterior draws, and models were cross-validated for out-of-sample predictive validity.

Findings

We estimated 569,000 deaths (95% UI 406,000-771,000) associated with bacterial AMR and 141,000 deaths (99,900-196,000) attributable to bacterial AMR among the 35 countries in the WHO Region of the Americas in 2019. Lower respiratory and thorax infections, as a syndrome, were responsible for the largest fatal burden of AMR in the region, with 189,000 deaths (149,000-241,000) associated with resistance, followed by bloodstream infections (169,000 deaths [94,200-278,000]) and peritoneal/intra-abdominal infections (118,000 deaths [78,600-168,000]). The six leading pathogens (by order of number of deaths associated with resistance) were Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. Together, these pathogens were responsible for 452,000 deaths (326,000-608,000) associated with AMR. Methicillin-resistant S. aureus predominated as the leading pathogen-drug combination in 34 countries for deaths attributable to AMR, while aminopenicillin-resistant E. coli was the leading pathogen-drug combination in 15 countries for deaths associated with AMR.

Interpretation

Given the burden across different countries, infectious syndromes, and pathogen-drug combinations, AMR represents a substantial health threat in the Americas. Countries with low access to antibiotics and basic health-care services often face the largest age-standardised mortality rates associated with and attributable to AMR in the region, implicating specific policy interventions. Evidence from this study can guide mitigation efforts that are tailored to the needs of each country in the region while informing decisions regarding funding and resource allocation. Multisectoral and joint cooperative efforts among countries will be a key to success in tackling AMR in the Americas.

Funding

Bill & Melinda Gates Foundation, Wellcome Trust, and Department of Health and Social Care using UK aid funding managed by the Fleming Fund.

Estimating mortality and disability in Peru before the COVID-19 pandemic: a systematic analysis from the Global Burden of the Disease Study 2019

Background

Estimating and analyzing trends and patterns of health loss are essential to promote efficient resource allocation and improve Peru's healthcare system performance.

Methods

Using estimates from the Global Burden of Disease (GBD), Injuries, and Risk Factors Study (2019), we assessed mortality and disability in Peru from 1990 to 2019. We report demographic and epidemiologic trends in terms of population, life expectancy at birth (LE), mortality, incidence, prevalence, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) caused by the major diseases and risk factors in Peru. Finally, we compared Peru with 16 countries in the Latin American (LA) region.

Results

The Peruvian population reached 33.9 million inhabitants (49.9% women) in 2019. From 1990 to 2019, LE at birth increased from 69.2 (95% uncertainty interval 67.8-70.3) to 80.3 (77.2-83.2) years. This increase was driven by the decline in under-5 mortality (-80.7%) and mortality from infectious diseases in older age groups (+60 years old). The number of DALYs in 1990 was 9.2 million (8.5-10.1) and reached 7.5 million (6.1-9.0) in 2019. The proportion of DALYs due to non-communicable diseases (NCDs) increased from 38.2% in 1990 to 67.9% in 2019. The all-ages and age-standardized DALYs rates and YLLs rates decreased, but YLDs rates remained constant. In 2019, the leading causes of DALYs were neonatal disorders, lower respiratory infections (LRIs), ischemic heart disease, road injuries, and low back pain. The leading risk factors associated with DALYs in 2019 were undernutrition, high body mass index, high fasting plasma glucose, and air pollution. Before the COVID-19 pandemic, Peru experienced one of the highest LRIs-DALYs rates in the LA region.

Conclusion

In the last three decades, Peru experienced significant improvements in LE and child survival and an increase in the burden of NCDs and associated disability. The Peruvian healthcare system must be redesigned to respond to this epidemiological transition. The new design should aim to reduce premature deaths and maintain healthy longevity, focusing on effective coverage and treatment of NCDs and reducing and managing the related disability.

151. Molecular diversity and resistance mechanisms of Klebsiella pneumoniae bloodstream infections in Peru

Background

Klebsiella pneumoniae, a leading pathogen for mortality associated with antimicrobial resistance (AMR), was responsible for > 250,000 deaths in 2019. Genomic surveillance can guide the development of vaccines and new antibiotics against this pathogen. While AMR disproportionally affects low-and middle-income countries, limited genomic data are available from these countries. To close this gap, this study provides genomic characterization of K. pneumoniae blood isolates recovered in Peru.

Methods

Consecutive non-duplicate K. pneumoniae blood culture isolates were collected during an AMR surveillance study (VIRAPERU) from Jul 2017 to Oct 2019, from 15 tertiary hospitals from 13 regions of Peru. DNA extraction (GeneJET, Thermo Fisher Scientific), DNA library (Nextera XT, Illumina) and genome sequencing (MiSeq 500bp-V2, Illumina) were conducted. De novo assembling (SPAdes v3.13.1), quality assessment and annotation (Nullarbor v2.0), and identification of species, ST group, K/O loci, AMR (Kleborate v2.0.1) were conducted. Phylogenetic trees were built with Microreact v.192.

Results

From 119 K. pneumoniae isolates, 114 were recovered and confirmed to belong to the Klebsiella taxon. Six species were identified, the most prevalent being K. pneumoniae (106), followed by K. quasipneumoniae (3). Among carbapenem-resistant isolates (n=13), 10 (77%) carried the bla_NDM-1 gene, while other three carried bla_KPC-2 (1), bla_IMP-16 (1) or no carbapenemase (1). Phenotypic co-resistance to colistin was present in 2 isolates, both negative for mcr-1 gene. The most common mechanisms of resistance to 3^rd generation cephalosporins, quinolones and to aminoglycosides were CTX-M-15 (74.4%), qnrB (63.6%), aac(6')-Ib-cr (87.5%), respectively. Many other AMR genetic determinants were identified (Fig. 1). Sixty ST groups were identified, but only 6 ST groups carried a carbapenemase gene (Fig. 2). A wide diversity of K and O locus was also identified (54 distinct K-loci and 14 distinct O-loci). Figure 1.

Genomic surveillance for multidrug-resistant or hypervirulent Klebsiella pneumoniae among United States bloodstream isolates

BACKGROUND

Klebsiella pneumoniae strains have been divided into two major categories: classical K. pneumoniae, which are frequently multidrug-resistant and cause hospital-acquired infections in patients with impaired defenses, and hypervirulent K. pneumoniae, which cause severe community-acquired and disseminated infections in normal hosts. Both types of infections may lead to bacteremia and are associated with significant morbidity and mortality. The relative burden of these two types of K. pneumoniae among bloodstream isolates within the United States is not well understood.

METHODS

We evaluated consecutive K. pneumoniae isolates cultured from the blood of hospitalized patients at Northwestern Memorial Hospital (NMH) in Chicago, Illinois between April 2015 and April 2017. Bloodstream isolates underwent whole genome sequencing, and sequence types (STs), capsule loci (KLs), virulence genes, and antimicrobial resistance genes were identified in the genomes using the bioinformatic tools Kleborate and Kaptive. Patient demographic, comorbidity, and infection information, as well as the phenotypic antimicrobial resistance of the isolates were extracted from the electronic health record. Candidate hypervirulent isolates were tested in a murine model of pneumonia, and their plasmids were characterized using long-read sequencing. We also extracted STs, KLs, and virulence and antimicrobial resistance genes from the genomes of bloodstream isolates submitted from 33 United States institutions between 2007 and 2021 to the National Center for Biotechnology Information (NCBI) database.

RESULTS

Consecutive K. pneumoniae bloodstream isolates (n = 104, one per patient) from NMH consisted of 75 distinct STs and 51 unique capsule loci. The majority of these isolates (n = 58, 55.8%) were susceptible to all tested antibiotics except ampicillin, but 17 (16.3%) were multidrug-resistant. A total of 32 (30.8%) of these isolates were STs of known high-risk clones, including ST258 and ST45. In particular, 18 (17.3%) were resistant to ceftriaxone (of which 17 harbored extended-spectrum beta-lactamase genes) and 9 (8.7%) were resistant to meropenem (all of which harbored a carbapenemase genes). Four (3.8%) of the 104 isolates were hypervirulent K. pneumoniae, as evidenced by hypermucoviscous phenotypes, high levels of virulence in a murine model of pneumonia, and the presence of large plasmids similar to characterized hypervirulence plasmids. These isolates were cultured from patients who had not recently traveled to Asia. Two of these hypervirulent isolates belonged to the well characterized ST23 lineage and one to the re-emerging ST66 lineage. Of particular concern, two of these isolates contained plasmids with tra conjugation loci suggesting the potential for transmission. We also analyzed 963 publicly available genomes of K. pneumoniae bloodstream isolates from locations within the United States. Of these, 465 (48.3%) and 760 (78.9%) contained extended-spectrum beta-lactamase genes or carbapenemase genes, respectively, suggesting a bias towards submission of antibiotic-resistant isolates. The known multidrug-resistant high-risk clones ST258 and ST307 were the predominant sequence types. A total of 32 (3.3%) of these isolates contained aerobactin biosynthesis genes and 26 (2.7%) contained at least two genetic features of hvKP strains, suggesting elevated levels of virulence. We identified 6 (0.6%) isolates that were STs associated with hvKP: ST23 (n = 4), ST380 (n = 1), and ST65 (n = 1).

CONCLUSIONS

Examination of consecutive isolates from a single center demonstrated that multidrug-resistant high-risk clones are indeed common, but a small number of hypervirulent K. pneumoniae isolates were also observed in patients with no recent travel history to Asia, suggesting that these isolates are undergoing community spread in the United States. A larger collection of publicly available bloodstream isolate genomes also suggested that hypervirulent K. pneumoniae strains are present but rare in the USA; however, this collection appears to be heavily biased towards highly antibiotic-resistant isolates (and correspondingly away from hypervirulent isolates).

Global burden of bacterial antimicrobial resistance in 2019: a systematic analysis

BACKGROUND

Antimicrobial resistance (AMR) poses a major threat to human health around the world. Previous publications have estimated the effect of AMR on incidence, deaths, hospital length of stay, and health-care costs for specific pathogen-drug combinations in select locations. To our knowledge, this study presents the most comprehensive estimates of AMR burden to date.

METHODS

We estimated deaths and disability-adjusted life-years (DALYs) attributable to and associated with bacterial AMR for 23 pathogens and 88 pathogen-drug combinations in 204 countries and territories in 2019. We obtained data from systematic literature reviews, hospital systems, surveillance systems, and other sources, covering 471 million individual records or isolates and 7585 study-location-years. We used predictive statistical modelling to produce estimates of AMR burden for all locations, including for locations with no data. Our approach can be divided into five broad components: number of deaths where infection played a role, proportion of infectious deaths attributable to a given infectious syndrome, proportion of infectious syndrome deaths attributable to a given pathogen, the percentage of a given pathogen resistant to an antibiotic of interest, and the excess risk of death or duration of an infection associated with this resistance. Using these components, we estimated disease burden based on two counterfactuals: deaths attributable to AMR (based on an alternative scenario in which all drug-resistant infections were replaced by drug-susceptible infections), and deaths associated with AMR (based on an alternative scenario in which all drug-resistant infections were replaced by no infection). We generated 95% uncertainty intervals (UIs) for final estimates as the 25th and 975th ordered values across 1000 posterior draws, and models were cross-validated for out-of-sample predictive validity. We present final estimates aggregated to the global and regional level.

FINDINGS

On the basis of our predictive statistical models, there were an estimated 4·95 million (3·62-6·57) deaths associated with bacterial AMR in 2019, including 1·27 million (95% UI 0·911-1·71) deaths attributable to bacterial AMR. At the regional level, we estimated the all-age death rate attributable to resistance to be highest in western sub-Saharan Africa, at 27·3 deaths per 100 000 (20·9-35·3), and lowest in Australasia, at 6·5 deaths (4·3-9·4) per 100 000. Lower respiratory infections accounted for more than 1·5 million deaths associated with resistance in 2019, making it the most burdensome infectious syndrome. The six leading pathogens for deaths associated with resistance (Escherichia coli, followed by Staphylococcus aureus, Klebsiella pneumoniae, Streptococcus pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa) were responsible for 929 000 (660 000-1 270 000) deaths attributable to AMR and 3·57 million (2·62-4·78) deaths associated with AMR in 2019. One pathogen-drug combination, meticillin-resistant S aureus, caused more than 100 000 deaths attributable to AMR in 2019, while six more each caused 50 000-100 000 deaths: multidrug-resistant excluding extensively drug-resistant tuberculosis, third-generation cephalosporin-resistant E coli, carbapenem-resistant A baumannii, fluoroquinolone-resistant E coli, carbapenem-resistant K pneumoniae, and third-generation cephalosporin-resistant K pneumoniae.

INTERPRETATION

To our knowledge, this study provides the first comprehensive assessment of the global burden of AMR, as well as an evaluation of the availability of data. AMR is a leading cause of death around the world, with the highest burdens in low-resource settings. Understanding the burden of AMR and the leading pathogen-drug combinations contributing to it is crucial to making informed and location-specific policy decisions, particularly about infection prevention and control programmes, access to essential antibiotics, and research and development of new vaccines and antibiotics. There are serious data gaps in many low-income settings, emphasising the need to expand microbiology laboratory capacity and data collection systems to improve our understanding of this important human health threat.

FUNDING

Bill & Melinda Gates Foundation, Wellcome Trust, and Department of Health and Social Care using UK aid funding managed by the Fleming Fund.

Underutilization and Quality Gaps in Blood Culture Processing in Public Hospitals of Peru

Correct processing of blood cultures may impact individual patient management, antibiotic stewardship, and scaling up of antimicrobial resistance surveillance. To assess the quality of blood culture processing, we conducted four assessments at 16 public hospitals across different regions of Peru. We assessed the following standardized quality indicators: 1) positivity and contamination rates, 2) compliance with recommended number of bottles/sets and volume of blood sampled, 3) blood culture utilization, and 4) possible barriers for compliance with recommendations. Suboptimal performance was found, with a median contamination rate of 4.2% (range 0-15.1%), with only one third of the participating hospitals meeting the target value of < 3%; and a median positivity rate of 4.9% (range 1-8.1%), with only 6 out of the 15 surveilled hospitals meeting the target of 6-12%. None of the assessed hospitals met both targets. The median frequency of solitary blood cultures was 71.9% and only 8.9% (N = 59) of the surveyed adult bottles met the target blood volume of 8 - 12 mL, whereas 90.5% (N = 602) were underfilled. A high frequency of missed opportunities for ordering blood cultures was found (69.9%, 221/316) among patients with clinical indications for blood culture sampling. This multicenter study demonstrates important shortcomings in the quality of blood culture processing in public hospitals of Peru. It provides a national benchmark of blood culture utilization and quality indicators that can be used to monitor future quality improvement studies and diagnostic stewardship policies.

Association between convalescent plasma treatment and mortality in COVID-19: a collaborative systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ).

METHODS

In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence.

RESULTS

A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis.

CONCLUSIONS

Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care.

Aminoglycoside-resistance gene signatures are predictive of aminoglycoside MICs for carbapenem-resistant Klebsiella pneumoniae

BACKGROUND

Aminoglycoside-containing regimens may be an effective treatment option for infections caused by carbapenem-resistant Klebsiella pneumoniae (CR-Kp), but aminoglycoside-resistance genes are common in these strains. The relationship between the aminoglycoside-resistance genes and aminoglycoside MICs remains poorly defined.

OBJECTIVES

To identify genotypic signatures capable of predicting aminoglycoside MICs for CR-Kp.

METHODS

Clinical CR-Kp isolates (n = 158) underwent WGS to detect aminoglycoside-resistance genes. MICs of amikacin, gentamicin, plazomicin and tobramycin were determined by broth microdilution (BMD). Principal component analysis was used to initially separate isolates based on genotype. Multiple linear regression was then used to generate models that predict aminoglycoside MICs based on the aminoglycoside-resistance genes. Last, the performance of the predictive models was tested against a validation cohort of 29 CR-Kp isolates.

RESULTS

Among the original 158 CR-Kp isolates, 91.77% (145/158) had at least one clinically relevant aminoglycoside-resistance gene. As a group, 99.37%, 84.81%, 82.28% and 10.76% of the CR-Kp isolates were susceptible to plazomicin, amikacin, gentamicin and tobramycin, respectively. The first two principal components explained 72.23% of the total variance in aminoglycoside MICs and separated isolates into four groups with aac(6')-Ib, aac(6')-Ib', aac(6')-Ib+aac(6')-Ib' or no clinically relevant aminoglycoside-resistance genes. Regression models predicted aminoglycoside MICs with adjusted R2 values of 56%-99%. Within the validation cohort, the categorical agreement when comparing the observed BMD MICs with the predicated MICs was 96.55%, 89.66%, 86.21% and 82.76% for plazomicin, gentamicin, amikacin and tobramycin, respectively.

CONCLUSIONS

Susceptibility to each aminoglycoside varies in CR-Kp. Detection of aminoglycoside-resistance genes may be useful to predict aminoglycoside MICs for CR-Kp.

Optimizing aminoglycoside selection for KPC-producing Klebsiella pneumoniae with the aminoglycoside-modifying enzyme (AME) gene aac(6')-Ib

OBJECTIVES

KPC-producing Klebsiella pneumoniae (KPC-Kp) isolates commonly co-harbour the aminoglycoside-modifying enzyme (AME) gene aac(6')-Ib, which encodes an AME that can confer resistance to some of the commercially available aminoglycosides. We sought to determine the influence of AAC(6')-Ib in KPC-Kp on the pharmacodynamic activity of aminoglycosides.

METHODS

Six KPC-Kp clinical isolates, three with and three without aac(6')-Ib, were analysed. Using these isolates, the bacterial killing of amikacin, gentamicin and tobramycin was assessed in static time-kill experiments. The pharmacodynamic activity of the aminoglycosides was then assessed in a dynamic one-compartment infection model over 72 h using simulated human pharmacokinetics of once-daily dosing with amikacin (15 mg/kg), gentamicin (5 mg/kg) and tobramycin (5 mg/kg).

RESULTS

At clinically relevant aminoglycoside concentrations in time-kill experiments and the dynamic one-compartment model, gentamicin was more active than amikacin or tobramycin against the isolates harbouring aac(6')-Ib. Amikacin, gentamicin and tobramycin all showed progressively reduced bacterial killing with exposure to repeated doses against most isolates in the dynamic one-compartment model. MIC values were generally not a good predictor of gentamicin pharmacodynamic activity against KPC-Kp, but were more reliable for amikacin and tobramycin.

CONCLUSIONS

Gentamicin may be preferred over amikacin or tobramycin for treatment of KPC-Kp infections. However, gentamicin MICs are not a consistent predictor of its pharmacodynamic activity and unexpected treatment failures are possible.

Randomized clinical trial to evaluate safety and efficacy of convalescent plasma use among hospitalized patients with COVID-19 (PERUCONPLASMA): a structured summary of a study protocol for a randomized controlled trial

Objectives

The general objective of this study is to test the hypothesis that administration of convalescent plasma from donors with previous diagnosis of severe COVID-19 pneumonia is safe and associated with a decrease in all-cause in-hospital mortality among hospitalized patients with COVID-19 at 30 days in comparison with standard treatment alone.

The secondary objectives are as follows: (1) to assess the efficacy of convalescent plasma to reduce the length of hospitalization, (2) to assess the efficacy of convalescent plasma to reduce the length of ICU stay, and (3) to assess the efficacy of convalescent plasma on reducing the requirement of invasive mechanical ventilation or ICU stay.

Trial design

PERUCONPLASMA is a IIb phase open label, randomized, superiority clinical trial with 1:1 allocation taking place in real life routine clinical practice at public hospitals in Lima, Peru. Participants will be randomized to receive convalescent plasma along with local standard treatment or local standard treatment alone. After allocation, all participants will be followed for a total of 30 days or until hospital discharge, whichever occurs first.

Participants

The population for the study are patients with severe disease with a confirmed laboratory test for SARS-CoV-2 infection hospitalized in 3 tertiary-care hospitals in Lima, Peru.

Subjects are eligible for the trial if they meet all of the following inclusion criteria:

Age 18 or older

Hospitalization due to COVID-19 with laboratory confirmation (either with serologic, molecular, or antigen test along with a compatible clinical presentation)

Severe or critical COVID-19 disease

Severe illness was defined by 2 or more of the following:

Respiratory rate of 22 or more

Hypoxemia with oxygen saturation equal or less than 93%

Abnormal blood gas analysis (PaO₂ < 60 mmHg, PaCO₂ > 50 mmHg, or Pa/FiO₂ < 300)

Critical disease was defined by either:

Mechanical ventilation requirement less than 72 h.

Shock.

4.

Capacity to provide informed consent (patient or patient’s direct relative)

5.

Availability of convalescent plasma units compatible with ABO blood type of the subject.

Exclusion criteria:

Subjects are not eligible for the trial if they meet any of the following criteria:

Contraindication for transfusion (e.g., prior anaphylaxis, congestive heart failure)

Hemodynamic instability (PA < 60 mmHg refractory to vasopressors)

Uncontrolled concomitant infections\

Stupor or coma

Platelets < 50,000/μL or disseminated intravascular coagulation

Serum creatinine > 3.5 mg/dL or dialysis requirement

Total bilirubin > 6 mg/dL or jaundice of unknown etiology

Myocardial infarction or acute coronary syndrome

Active or recent (< 7 days) intracranial hemorrhage

Pregnancy

Donors:

The donors have to meet the following criteria: male between 30 and 60 years with a previous diagnosis of severe COVID-19-associated pneumonia within the last 3 months, with resolution of symptoms of at least 28 days. The rationale for including donors with severe disease is to maximize the probability of collecting convalescent plasma units with high titer of neutralizing antibodies, as the technology to measure this specific type of antibodies is not routinely available in Peru. Aliquots of plasma will be stored for future quantification of neutralizing antibodies.

Intervention and comparator

Convalescent plasma from donors with previous severe COVID-19 is the investigational medical product.

The experimental group will receive 1 to 2 units of 200 to 250 ml of convalescent plasma along with local standard treatment. The control group will receive local standard treatment alone. The participants randomized to plasma will have evaluations at 6 h and 24 h to specifically evaluate possible post transfusion events. All the participants will be evaluated at day 3, day 7, and day 30 after enrolment.

Main outcomes

Safety outcome:

Incidence of serious adverse reactions related to convalescent plasma transfusion within 24 h after convalescent plasma administration.

Efficacy outcomes:

Mortality from any cause during hospitalization at 30 days post randomization.

Length of hospitalization at 30 days post randomization or until hospital discharge.

Duration of mechanical ventilation at 30 days post randomization or until hospital discharge.

Length of hospitalization in an intensive care unit at 30 days post randomization or until hospital discharge.

Exploratory:

Oxygen requirement evolution at days 3 and 7.

Score Sequential Organ Failure Assessment (SOFA) evolution at days 3 and 7.

Dynamics of inflammatory marker (lymphocyte, C-reactive protein (CRP), D-dimer, lactate dehydrogenase (LDH)) evolution at days 3 and 7.

Proportion of patients progressing to multi-organ failure at 30 days post randomization or until hospital discharge.

Proportion of transfusion related adverse reactions at 30 days post randomization or until hospital discharge.

Randomization

Randomization will be carried out within the electronic case report form (eCRF) in 1:1 ratio (receive plasma/control) in a randomization process established by blocks of size 2, 4, and 6. Allocation to the treatment arm of an individual patient will not be available to the investigators before completion of the whole randomization process. Randomization blocks will be performed with “ralloc”, Stata’s randomization process v.16.0. Randomization through the eCRF will be available 24 h every day.

Blinding (masking)

Both the participants and study staff will be aware of the allocated intervention.

Blinded statistical analysis will be performed.

Numbers to be randomized (sample size)

The sample size was calculated using the Fleiss formula with continuity correction to detect a mortality reduction from 50 to 20% between the two treatment arms with a confidence level of 95% and a power of 80%. Based on this information, a total of 45 patients per arm would be needed. After adjustment for a drop-out rate of 10% after enrolment, a total of 50 patients per arm (100 patients in total) will be enrolled.

Trial status

Current protocol version: 5.0 dated January 04, 2021.

Recruitment started on September 21, 2020, and is expected to finish by the end of March 2021.

Trial registration

Peruvian Register of Clinical Trials (REPEC) ID: PER-016-20, registered on June 27, 2020.

Clinicaltrials.gov ID: NCT04497324, registered on August 4, 2020.

Full protocol

The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this letter serves as a summary of the key elements of the full protocol.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05189-6.

1189. A Comprehensive Characterization of the Emerging Carbapenem-Resistant Klebsiella pneumoniae Clinical Isolates From a Public Hospital in Lima, Peru

Background

In contrast with other countries in Latin America, Peru had been notoriously spared by the global dissemination of carbapenem-resistant Klebsiella pneumoniae (CR-Kp), until recently. Even though, isolated cases of KPC-producing K. pneumoniae had been reported since 2013, it was not until 2016 that the first outbreak of NDM- producing K. pneumoniae was described in Peru. By 2017, rapid emergence of CR-Kp took place in Hospital Cayetano Heredia (HCH), a tertiary care hospital in Lima. Here, we provide a description of clinical, microbiological and molecular characteristics of CR-Kp isolates recovered at HCH.

Methods

Retrospective review of all CR-Kp clinical isolates recovered at HCH until December 2017. Antibiotic susceptibility data were obtained during routine care (Vitek or disc diffusion) and was assessed using CLSI breakpoints. DNA extraction was performed by heat shock, and PCR was performed to assess carriage of blaNDM gene. String test was performed to detect hypermucoviscosity.

Results

The first case of CR-Kp in HCH dated from July 2015. Since then, a total of 69 CR-Kp clinical isolates, from 60 patients have been recovered until December 2017. A significant increase in the number of cases was observed during 2017 (Figure 1). The average age of patients was 55. Urinary, and respiratory sources of infection or colonization were the most common ones (35% and 30%, respectively), followed by blood stream (17%) and intraabdominal (10%) infections. Isolate recovery and DNA extraction was achieved in 40 cases. Of these, 15 (38%) had a positive PCR for blaNDM carbapenemase gene (Figure 2). Antibiotic susceptibility testing revealed that amikacin was the most effective antimicrobial with the rest of antimicrobials having extremely high rates of resistance (Figure 3). String test was positive in two of these isolates, suggesting that hypervirulent CR-KP might be emerging in this region.

Conclusion

An epidemic of CR-Kp has established in our hospital, representing the first one reported in Peru. The different mechanisms of carbapenem resistance found suggest a polyclonal expansion. Amikacin remains the only active antimicrobial within the routinely tested antibiotics, highlighting the need to add other antimicrobials to the routine panel.

Disclosures

All authors: No reported disclosures.

Case Report of an Extensively Drug-Resistant Klebsiella pneumoniae Infection With Genomic Characterization of the Strain and Review of Similar Cases in the United States

Reports of extensively drug-resistant and pan-drug-resistant Klebsiella pneumoniae (XDR-KP and PDR-KP) cases are increasing worldwide. Here, we report a case of XDR-KP with an in-depth molecular characterization of resistance genes using whole-genome sequencing, and we review all cases of XDR-KP and PDR-KP reported in the United States to date.

Geographic predictors of primary multidrug-resistant tuberculosis cases in an endemic area of Lima, Peru

SETTING

Peru reports among the highest multidrug-resistant tuberculosis (MDR-TB) rates in the Americas, with a growing proportion in previously untreated tuberculosis (TB) cases. The identification of clusters of primary MDR-TB compared with drug-susceptible TB (DS-TB) could help prioritize interventions.

OBJECTIVE

To examine the clustering of primary MDR-TB case residences and their proximity to high-risk locations in San Juan de Lurigancho District, Lima, Peru.

DESIGN

Enrolled primary MDR-TB and primary DS-TB cases were interviewed and their primary residence was recorded using handheld Global Positioning System devices. Kuldorff's spatial scan statistic was used for cluster detection (SaTScan(TM), v. 9.1.1). Identified clusters were visualized in Quantum Geographic Information Systems software (v1.8.0). The following cluster centers were tested: a health centre with the highest TB and MDR-TB rates (Clinic X), a hospital and two prisons. Using regression analyses, we examined predictors of primary MDR-TB cases.

RESULTS

A statistically significant cluster of primary MDR-TB cases was identified within a 2.29 km radius around Clinic X. Proximity to Clinic X remained a significant predictor of primary MDR-TB in adjusted regression analyses.

CONCLUSION

We identified a hotspot of primary MDR-TB cases around Clinic X in a TB-endemic area. Causes of this clustering require investigation; targeted interventions for this high-risk area should be considered.

Public transportation and tuberculosis transmission in a high incidence setting

Background

Tuberculosis (TB) transmission may occur with exposure to an infectious contact often in the setting of household environments, but extra-domiciliary transmission also may happen. We evaluated if using buses and/or minibuses as public transportation was associated with acquiring TB in a high incidence urban district in Lima, Peru.

Methods

Newly diagnosed TB cases with no history of previous treatment and community controls were recruited from August to December 2008 for a case-control study. Crude and adjusted odd ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression to study the association between bus/minibus use and TB risk.

Results

One hundred forty TB cases and 80 controls were included. The overall use of buses/minibuses was 44.9%; 53.3% (72/135) among cases and 30.4% (24/79) among controls [OR: 3.50, (95% CI: 1.60–7.64)]. In the TB group, 25.7% (36/140) of subjects reported having had a recent household TB contact, and 13% (18/139) reported having had a workplace TB contact; corresponding figures for controls were 3.8% (3/80) and 4.1% (3/73), respectively[OR: 8.88 (95% CI: 2.64–29.92), and OR: 3.89 (95% CI: 1.10–13.70)]. In multivariate analyses, age, household income, household contact and using buses/minibuses to commute to work were independently associated with TB [OR for bus/minibus use: 11.8 (95% CI: 1.45–96.07)].

Conclusions

Bus/minibus use to commute to work is associated with TB risk in this high-incidence, urban population in Lima, Peru. Measures should be implemented to prevent TB transmission through this exposure.

High prevalence of primary multidrug resistant tuberculosis in persons with no known risk factors

Introduction

In high multidrug resistant (MDR) tuberculosis (TB) prevalence areas, drug susceptibility testing (DST) at diagnosis is recommended for patients with risk factors for MDR. However, this approach might miss a substantial proportion of MDR-TB in the general population. We studied primary MDR in patients considered to be at low risk of MDR-TB in Lima, Peru.

Methods

We enrolled new sputum smear-positive TB patients who did not report any MDR-TB risk factor: known exposure to a TB patient whose treatment failed or who died or who was known to have MDR-TB; immunosuppressive co-morbidities, ex prison inmates; prison and health care workers; and alcohol or drug abuse. A structured questionnaire was applied to all enrolled participants to confirm the absence of these factors and thus minimize underreporting. Sputum from all participants was cultured on Löwenstein-Jensen media and DST for first line drugs was performed using the 7H10 agar method.

Results

Of 875 participants with complete data, 23.2% (203) had risk factors for MDR-TB elicited after enrolment. Among the group with no reported risk factors who had a positive culture, we found a 6.3% (95%CI 4.4–8.3) (37/584) rate of MDR-TB. In this group no epidemiological characteristics were associated with MDR-TB. Thus, in this group, multidrug resistance occurred in patients with no identifiable risk factors.

Conclusions

We found a high rate of primary MDR-TB in a general population with no identifiable risk factors for MDR-TB. This suggests that in a high endemic area targeting patients for MDR-TB based on the presence of risk factors is an insufficient intervention.

Self-reported risks for multiple-drug resistance among new tuberculosis cases: implications for drug susceptibility screening and treatment

BACKGROUND

Multiple drug-resistance in new tuberculosis (TB) cases accounts for the majority of all multiple drug-resistant TB (MDR-TB) worldwide. Effective control requires determining which new TB patients should be tested for MDR disease, yet the effectiveness of global screening recommendations of high-risk groups is unknown.

METHODS

Sixty MDR-TB cases with no history of previous TB treatment, 80 drug-sensitive TB and 80 community-based controls were recruited in Lima, Peru between August and December, 2008 to investigate whether recommended screening practices identify individuals presenting with MDR-TB. Odd ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression to study the association of potential risk factors with case/control variables.

RESULTS

MDR-TB cases did not differ from drug-sensitive TB and community controls in rates of human immunodeficiency virus infection, reported hospital or prison visits in the 3 years prior to diagnosis. MDR-TB cases were more likely than drug-sensitive TB controls to have had a recent MDR-TB household contact (OR 4.66, (95% CI 1.56-13.87)); however, only 15 cases (28.3%) reported this exposure. In multivariate modeling, recent TB household contact, but not contact with an MDR-TB case, remained predictive of MDR-TB, OR 7.47, (95% CI 1.91-29.3). Living with a partner rather than parents was associated with a lower risk of MDR-TB, OR 0.15, (95% CI 0.04-0.51).

CONCLUSION

Targeted drug susceptibility testing (DST) linked to reported MDR-TB contact or other high-risk exposures does not identify the majority of new TB cases with MDR disease in Lima where it is endemic. All new TB cases should be screened with DST to identify MDR patients. These findings are likely applicable to other regions with endemic MDR-TB.

Rapid molecular detection of tuberculosis and rifampin resistance

BACKGROUND

Global control of tuberculosis is hampered by slow, insensitive diagnostic methods, particularly for the detection of drug-resistant forms and in patients with human immunodeficiency virus infection. Early detection is essential to reduce the death rate and interrupt transmission, but the complexity and infrastructure needs of sensitive methods limit their accessibility and effect.

METHODS

We assessed the performance of Xpert MTB/RIF, an automated molecular test for Mycobacterium tuberculosis (MTB) and resistance to rifampin (RIF), with fully integrated sample processing in 1730 patients with suspected drug-sensitive or multidrug-resistant pulmonary tuberculosis. Eligible patients in Peru, Azerbaijan, South Africa, and India provided three sputum specimens each. Two specimens were processed with N-acetyl-L-cysteine and sodium hydroxide before microscopy, solid and liquid culture, and the MTB/RIF test, and one specimen was used for direct testing with microscopy and the MTB/RIF test.

RESULTS

Among culture-positive patients, a single, direct MTB/RIF test identified 551 of 561 patients with smear-positive tuberculosis (98.2%) and 124 of 171 with smear-negative tuberculosis (72.5%). The test was specific in 604 of 609 patients without tuberculosis (99.2%). Among patients with smear-negative, culture-positive tuberculosis, the addition of a second MTB/RIF test increased sensitivity by 12.6 percentage points and a third by 5.1 percentage points, to a total of 90.2%. As compared with phenotypic drug-susceptibility testing, MTB/RIF testing correctly identified 200 of 205 patients (97.6%) with rifampin-resistant bacteria and 504 of 514 (98.1%) with rifampin-sensitive bacteria. Sequencing resolved all but two cases in favor of the MTB/RIF assay.

CONCLUSIONS

The MTB/RIF test provided sensitive detection of tuberculosis and rifampin resistance directly from untreated sputum in less than 2 hours with minimal hands-on time. (Funded by the Foundation for Innovative New Diagnostics.)

Accounting for autocorrelation in multi-drug resistant tuberculosis predictors using a set of parsimonious orthogonal eigenvectors aggregated in geographic space

Spatial autocorrelation is problematic for classical hierarchical cluster detection tests commonly used in multi-drug resistant tuberculosis (MDR-TB) analyses as considerable random error can occur. Therefore, when MDRTB clusters are spatially autocorrelated the assumption that the clusters are independently random is invalid. In this research, a product moment correlation coefficient (i.e., the Moran's coefficient) was used to quantify local spatial variation in multiple clinical and environmental predictor variables sampled in San Juan de Lurigancho, Lima, Peru. Initially, QuickBird 0.61 m data, encompassing visible bands and the near infra-red bands, were selected to synthesize images of land cover attributes of the study site. Data of residential addresses of individual patients with smear-positive MDR-TB were geocoded, prevalence rates calculated and then digitally overlaid onto the satellite data within a 2 km buffer of 31 georeferenced health centers, using a 10 m2 grid-based algorithm. Geographical information system (GIS)-gridded measurements of each health center were generated based on preliminary base maps of the georeferenced data aggregated to block groups and census tracts within each buffered area. A three-dimensional model of the study site was constructed based on a digital elevation model (DEM) to determine terrain covariates associated with the sampled MDR-TB covariates. Pearson's correlation was used to evaluate the linear relationship between the DEM and the sampled MDR-TB data. A SAS/GIS(R) module was then used to calculate univariate statistics and to perform linear and non-linear regression analyses using the sampled predictor variables. The estimates generated from a global autocorrelation analyses were then spatially decomposed into empirical orthogonal bases using a negative binomial regression with a non-homogeneous mean. Results of the DEM analyses indicated a statistically non-significant, linear relationship between georeferenced health centers and the sampled covariate elevation. The data exhibited positive spatial autocorrelation and the decomposition of Moran's coefficient into uncorrelated, orthogonal map pattern components revealed global spatial heterogeneities necessary to capture latent autocorrelation in the MDR-TB model. It was thus shown that Poisson regression analyses and spatial eigenvector mapping can elucidate the mechanics of MDR-TB transmission by prioritizing clinical and environmental-sampled predictor variables for identifying high risk populations.

Bodyweight gain to predict treatment outcome in patients with pulmonary tuberculosis in Peru

SETTING

Tuberculosis control programmes of two health care centres in the central rainforest of Peru.

OBJECTIVE

To evaluate if bodyweight gain (BWG) predicts treatment outcome in patients with pulmonary tuberculosis (PTB).

DESIGN

Retrospective cohort study of adults with PTB diagnosed between 1995 and 2004. BWG was assessed after month 1 of treatment, after the initial phase and at the end of treatment. Patients were stratified into two BWG categories, < or = 5% and >5%. Failures and relapses were grouped together as unsuccessful treatment outcome.

RESULTS

A total of 650 patients were included: 7.2% (n = 47) had an unsuccessful outcome. Unsuccessful outcome was associated with BWG < or = 5% at the end of treatment (RR 2.05, 95%CI 1.10-3.80), but not at the completion of month 1 (RR 0.99, 95%CI 0.52-1.88) or at completion of the initial phase (RR 1.46, 95%CI 0.82-2.57). Median BWG at completion of the initial phase was higher in cured patients (P = 0.007). BWG < or = 5% at end of treatment (RR 2.35, 95%CI 1.17-4.72), initial sputum smear 2+ (RR 2.48, 95%CI 1.14-5.31) and positive smear microscopy at month 2 (RR 4.0, 95%CI 1.30-12.31) were independent predictors of unsuccessful treatment outcome.

CONCLUSION

BWG < or = 5% at the end of treatment, high bacterial load and lack of sputum conversion correlate with unsuccessful treatment outcome in this setting. New discriminative cut-offs for BWG are proposed.