Transmitted Drug Resistance Research Articles

Deubiquitylation of Rab35 by USP32 promotes the transmission of imatinib resistance by enhancing exosome secretion in gastrointestinal stromal tumours.

Imatinib is a tyrosine kinase inhibitor that is widely used to combat gastrointestinal stromal tumours (GISTs). However, secondary resistance to imatinib is an important challenge in GIST treatment. Recent studies have demonstrated that cancer-derived nanosized exosomes play a key role in intercellular communication, but little is known about the roles of exosomes in imatinib-resistant GISTs. Here, we reveal that exosomes released from imatinib-resistant GISTs transmit drug resistance to imatinib-sensitive tumours. By using iTRAQ technology, we demonstrate that Ras-related protein Rab-35 (Rab35) is upregulated differentially in imatinib-resistant GISTs. Loss of Rab35 decreases exosome secretion, thereby hampering the transmission of imatinib resistance to sensitive tumours. Mechanistically, we showed that the ubiquitin‒proteasome system is involved in elevated Rab35 expression and that ubiquitin-specific protease 32 (USP32), a deubiquitylating enzyme, is bound to Rab35. Further experiments demonstrate that this protease protects Rab35 from proteasomal degradation by reducing Lys48 (K48)-ubiquitination. Additionally, we found that the transcription factor ETV1, which is a lineage survival factor in GISTs, promotes USP32 expression. Collectively, our results reveal that exosomes transmit imatinib resistance in GISTs and that deubiquitylation plays a key role in regulating the transmission process. The USP32-Rab35 axis provides a potential target for interventions to reduce the occurrence of imatinib resistance in GISTs.

Study of the molecular characteristics and homology of carbapenem-resistant Proteus mirabilis by whole genome sequencing.

Introduction. Proteus mirabilis is part of the family Enterobacteriaceae, and is naturally resistant to various antimicrobial drugs. In recent years, outbreaks of severe nosocomial infections caused by carbapenem-resistant P. mirabilis (CR-PMI) have been frequently reported. Few studies exist on the whole-genome molecular characteristics of this bacterium in China and elsewhere, which stimulated the implementation of this study.Hypothesis. CR-PMI strains contained the multiple drug resistance genes and exhibited a high resistance rate to commonly used antimicrobial drugs.Aim. Our goals here were to identify resistance mechanisms and homology of CR-PMI strains and provide a theoretical basis for clinical treatment and controlling nosocomial infections.Methodology. Bacterial species identification was carried out using matrix-assisted laser desorption/ionization time of flight MS (MALDI-TOF-MS). Antimicrobial susceptibility was determined using the VITEK 2 system and Kirby-Bauer (K-B) disc-diffusion method. Whole-genome sequencing (WGS) was conducted by the Illumina platform NovaSeq sequencer. Antibiotic resistance genes (ARGs) were identified using the NCBI database with Abricate. Plasmid replicon types were identified using PlasmidFinder, available at the Center for Genomic Epidemiology.Results. Five CR-PMI strains collected in our hospital from July 2019 to September 2021 were resistant to almost all antimicrobial agents except aztreonam (ATM), amikacin (AMK) and cefotetan (CTT). All CR-PMI strains contained the carbapenem resistance gene New Delhi metallo-β-lactamase 1 (bla NDM-1), and two strains harboured extended-spectrum β-lactamase (ESBL) genes bla PER-4 and bla CTX-M-65. The five CR-PMI strains contained 27, 18, 30, 25 and 24 drug-resistance genes, respectively. Most antimicrobial resistance genes were detected for aminoglycosides (n=14), followed by cephalosporins (n=7). The phylogenetic tree was divided into five evolutionary groups, and the five CR-PMI strains were in the four evolutionary groups B-E.Conclusion Overall, CR-PMI strains exhibited a high resistance rate to commonly used antimicrobial drugs, and contained the carbapenem resistance gene bla NDM-1. The CR-PMI strains showed a polyclonal trend in different wards at different times. Most importantly, all strains identified contained important antimicrobial resistance genes, which may lead to severe drug resistance transmission and fatal multiple resistant bacterial infections.

Changes in HIV-1 Subtypes/Sub-Subtypes, and Transmitted Drug Resistance Among ART-Naïve HIV-Infected Individuals - China, 2004-2022.

The efficacy of treatment and clinical outcomes may be jeopardized by factors such as transmitted drug resistance (TDR) and the genetic diversity of the human immunodeficiency virus type 1 (HIV-1). This comprehensive study aims to examine the alterations in HIV-1 subtypes or sub-subtypes and TDR among Chinese individuals, who have been diagnosed with HIV infection and are previously untreated with antiretroviral therapy (ART), across the span of 2004 to 2022. Sequences of the HIV-1 pol gene region were obtained from ART-naïve HIV-positive individuals across 31 provincial-level administrative divisions between 2004 and 2022. To predict susceptibility to 12 antiretroviral drugs, the research utilized the Stanford HIV Drug Resistance Database. The Cochran-Armitage trend test facilitated the analysis of changes in HIV-1 subtype/sub-subtype prevalence and TDR. This analysis was conducted in alignment with the progression of the National Free Antiretroviral Treatment Program's stages between 2004 and 2022. Among the 57,902 ART-naïve individuals infected with HIV, there was a notable decline in the prevalence of CRF01_AE, B, and C from 37.3%, 24.1%, and 1.3% respectively in 2004-2007 to 29.4%, 7.3%, and 0.2% respectively in 2020-2022. Simultaneously, a significant increase was observed in the proportions of CRF07_BC, CRF08_BC, CRF55_01B, other CRFs, and URFs, from 24.1%, 11.5%, 0.1%, 0.4%, and 0.9% respectively in 2004-2007 to 40.8%, 11.5%, 3.8%, 3.7%, and 2.8% respectively in 2020-2022 (all P<0.001 for trend). The prevalence of TDR to overall, non-nucleoside reverse transcriptase inhibitor (NNRTI), efavirenz, and nevirapine also significantly increased from 2.6%, 1.8%, 1.6%, and 1.8% respectively in 2004-2007 to 7.8%, 6.7%, 6.3%, and 6.7% respectively in 2020-2022 (all P<0.001 for trend). However, there were no meaningful changes in the TDR prevalence of nucleoside reverse transcriptase inhibitor and protease inhibitor. Notably, in 2020-2022, the overall TDR prevalence exceeded 15% in Xinjiang. The total prevalence of TDR in China has achieved a moderate level (7.8%) from 2020 to 2022, with NNRTI resistance standing prominently at 6.7%. Consequently, measures to curb TDR are urgently required, particularly among ART-naïve HIV-infected individuals in China.

New insights on tuberculosis transmission dynamics and drug susceptibility profiles among the prison population in Southern Brazil based on whole-genome sequencing.

The rate of tuberculosis (TB) infection among the prison population (PP) in Brazil is 28 times higher than that in the general population, and prison environment favors the spread of TB. To describe TB transmission dynamics and drug resistance profiles in PP using whole-genome sequencing (WGS). This was a retrospective study of Mycobacterium tuberculosis cultivated from people incarcerated in 55 prisons between 2016 and 2019; only one isolate per prisoner was included. Information about movement from one prison to another was tracked. Clinical information was collected, and WGS was performed on isolates obtained at the time of TB diagnosis. Among 134 prisoners included in the study, we detected 16 clusters with a total of 58 (43%) cases of M. tuberculosis. Clusters ranged from two to seven isolates with five or fewer single nucleotide polymorphism (SNP) differences, suggesting a recent transmission. Six (4.4%) isolates were resistant to at least one anti-TB drug. Two of these clustered together and showed resistance to rifampicin, isoniazid, and fluoroquinolones, with 100% concordance between WGS and phenotypic drug-susceptibility testing. Prisoners with clustered isolates had a high amount of movement between prisons (two to eight moves) during the study period. WGS demonstrated the recent transmission of TB within prisons in Brazil. The high movement among prisoners seems to be related to the transmission of the same M. tuberculosis strain within the prison system. Screening for TB before and after the movement of prisoners using rapid molecular tests could play a role in reducing transmission.

Screening for carriers of carbapenemase producing Enterobacteriaceae in critical care units

Background: The increasing cases of carbapenemase resistant Enterobacteriaceae (CRE) across the world is a cause of concern. Asymptomatic carriage of CRE in critical care units is a menace to infection control. Aims: This study determines the carriage rate of CRE in patients admitted to the intensive care units (ICU's) and evaluates the potential risk factors, leading to colonization in patients with CRE. Materials and Methods: Sixty rectal swabs from patients in the ICU's were screened for carriage of CRE. The samples were inoculated onto ChromID CARBA SMART bi-plate. The organisms showing color appearances as per the manufacturer's instructions were considered as CRE. Routine disk diffusion technique was also employed and CRE was defined as an organism belonging to the Enterobacteriaceae family which was resistant to either imipenem or meropenem. Results: The organisms isolated were identified and the percentage of carriage of carbapenem-resistant organisms was 12 (20%), of which Klebsiella pneumoniae was 4 (33.3%), Escherichia coli 6 (50%), Citrobacter freundii 1 (8.3%), and Enterobacter spp. 1 (8.3%). Out of these, 2 (3.3%) showed OXA 48 type resistance seen with K. pneumoniae and E. coli. Prior hospitalization, the use of high-end antibiotics and patients who have undergone surgeries were the most common potential risk factors for colonization with CRE. Conclusion: The prompt detection of CRE by routine screening using cost-effective methods and reduction of potential risk factors for gut colonization reduce the transmission of drug resistance in any hospital setting and pave the way for better antibiotic stewardship and appropriate contact isolation precautions.

Primary resistance to integrase inhibitors in Shenzhen.

In recent years, integrase strand transfer inhibitor (INSTI)-containing regimens have been increasingly adopted in treatment for HIV/AIDS and promoted as non-occupational post-exposure prophylaxis in China. This study aims to describe the prevalence of resistance to integrase and drug resistance mutations (DRMs) among ART-naive patients in Shenzhen, China. Serum samples and demographic information were collected from newly reported ART-naive patients in Shenzhen in 2020. The study sequenced the coding sequence of the HIV-1 integrase gene and determined the DRMs.​. In this study, 1682 newly reported cases were included and 1071 of them were successfully sequenced finally. The prevalence of primary drug resistance was 1.77%, with 19 samples showing varying degrees of resistance to INSTIs. The study detected six major DRMs in 16 individuals and eight accessory DRMs in 24 individuals. The prevalence of transmitted drug resistance (TDR) mutations was 1.21%, with five transmitted mutations detected in 13 individuals. The prevalence of drug resistance to raltegravir and elvitegravir was statistically higher than to bictegravir, cabotegravir and dolutegravir. The prevalence of INSTI resistance in Shenzhen in 2020 was relatively high. ​Continued surveillance for resistance to INSTIs is recommended and treatment regimens should be adopted based on the pattern of resistance to INSTIs. ​Dolutegravir or bictegravir is first recommended when considering INSTIs as treatment regimens.

Low rate of pre-exposure prophylaxis and post-exposure prophylaxis uptake and high prevalence of transmitted drug resistance among newly diagnosed primary HIV infections in Shenzhen, China: a real-world retrospective study.

Understanding the characteristics of newly diagnosed primary human deficiency virus-1 (HIV-1) infection in the context of the post-antiretroviral therapy era and HIV drug prophylaxis is essential for achieving the new target of 95-95-95-95 by 2025. This study reported the characteristics of newly diagnosed primary HIV-1 infection in Shenzhen. This is a real-world retrospective study. Eighty-seven newly diagnosed primary HIV-1-infected patients were recruited from January 2021 to March 2022 at the Third People's Hospital of Shenzhen. Demographic, epidemiological, diagnostic, drug resistance, and medical data were described and analyzed. Overall, 96.6% (84/87) of the newly identified primary HIV-1-infected patients were male, including 88.5% (77/87) men have sex with men (MSM), with a median age of 29.0 years (Q1-Q3: 24.0-34.0 years); of these, 85.1% (74/87) reported high-risk sexual behaviors with casual partners. The rate of condom usage was only 28.7% (25/87). The overall rate of pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP) was 8.0% (7/87, including 4 PrEP and 3 PEP cases) around the potential exposure, although 41.4% of the patients had prior awareness of such interventions. Moreover, only 19.5% (17/87) had previously used PrEP or PEP. Of those, 58.8% (10/17) of the patients obtained drugs from the internet, and only 35.3% (6/17) reported good compliance. A total of 54.0% (47/87) of subjects were diagnosed by the HIV nucleic acid test. Acute retroviral syndrome appeared in 54.0% (47/87) of patients. The prevalence of transmitted drug resistance (TDR) mutation was 33.9% (19/56), including 6 (10.7%) against nucleoside reverse transcriptase inhibitor (NRTI) plus non-nucleoside reverse transcriptase inhibitor (NNRTI), 8 (14.3%) against NNRTI, and 5 (8.9%) against protease inhibitor (PI) only. Owing to the low utilization rate and incorrect usage of PrEP and PEP, massive efforts are needed to promote HIV-preventive strategies in the MSM population. The extremely high prevalence of TDR mutation in this population implies the need for future pretreatment drug resistance surveillance.

Transmitted Drug Resistance to Integrase-Based First-Line Human Immunodeficiency Virus Antiretroviral Regimens in Mediterranean Europe.

We evaluated the prevalence of transmitted drug resistance (TDR) to integrase strand-transfer inhibitors (INSTIs) and nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) and of clinically relevant resistance (CRR) in newly diagnosed people with human immunodeficiency virus (HIV; PWH) naive to antiretroviral therapy (ART) in Europe. MeditRes is a consortium that includes ART-naive PWH newly diagnosed in France, Greece, Italy, Portugal, and Spain during 2018-2021. Reverse transcriptase and INSTI sequences were provided by participating centers. To evaluate the prevalence of surveillance drug resistance mutations (SDRM), we used the calibrated population resistance tools from the Stanford HIV website. To evaluate CRR, defined as any resistance level ≥3, we used the Stanford HIV Drug Resistance Database v.9.1 algorithm. We included 2705 PWH, 72% men, median age of 37 years (interquartile range, 30-48); 43.7% were infected by non-B subtypes. The prevalence of INSTI-SDRMs was 0.30% (T66I, T66A, E92Q, E138T, E138K, Y143R, S147G, R263K; all n=1) and the prevalence of NRTI-SDRMs was 5.77% (M184V: 0.85%; M184I: 0.18%; K65R/N: 0.11%; K70E: 0.07%; L74V/I: 0.18%; any thymidine analog mutations: 4.36%). INSTI-CRR was 2.33% (0.15% dolutegravir/bictegravir, 2.29% raltegravir/elvitegravir) and 1.74% to first-line NRTIs (0.89% tenofovir/tenofovir alafenamide, 1.74% abacavir, 1.07% lamivudine/emtricitabine). We present the most recent data on TDR to integrase-based first-line regimens in Europe. Given the low prevalence of CRR to second-generation integrase inhibitors and to first-line NRTIs during 2018-2021, it is unlikely that newly diagnosed PWH in MeditRes countries would present with baseline resistance to a first-line regimen based on second-generation integrase inhibitors.

2068. Molecular and Clinical Features of New HIV-1 diagnoses in Northern Dominican Republic

Abstract Background Surveillance of transmitted drug resistance (TDR) and molecular epidemiology of newly diagnosed persons with HIV can impact care and prevention and inform efforts towards ending the HIV epidemic. Both interventions are not routinely available in the Dominican Republic (DO). Methods During 10/2019-4/2021, we attempted to enroll all newly HIV-diagnosed antiretroviral naïve adults (≥18 years) presenting at the regional hospital in Santiago, DO. Demographic, clinical and laboratory data were collected, and blood samples obtained for partial pol genotyping. Subtyping and resistance interpretation were done with Stanford Database tools. Maximum likelihood phylogenies were inferred by RAxML and clusters were defined as clades with bootstrap support of ≥0.8. Extended phylogenetic analyses included ∼1,500 publicly available Caribbean sequences. Demographics and TDR were compared by cluster status using Fisher Exact or Wilcoxon rank sum tests. Results Of 100 HIV-diagnosed participants (mean age 40 years; 61% male; 84% heterosexual; 50% never tested prior), 56% were hospitalized, 48% tested via doctor advise and 28% for feeling sick. Available CD4 count was &amp;lt; 200 cells/µL in 49% (43/87) more prevalent (vs CD4 &amp;gt;200) in heterosexuals (93% vs 7% in gay/bisexuals; p=0.003). Genotyping from 68/100, were 29% HIV-1 subtype B, 69% B-containing recombinants and one HIV-1 subtype C. TDR was in 12% (95% CI: 5-22%), all to NNRTIs (K103N and Y188L most common; two with multiple mutations). Six identified clusters included 25% of participants, 92% from downtown Santiago. Individuals in the largest 6-member cluster met partners online and were gay/bisexual. Participants in clusters had higher TDR (24% vs 8%, p=0.100), were younger (34 vs 43 years, p=0.01), and were gay/bisexual (41% vs 8%, p=0.003). In extended phylogenetic analyses participant sequences clustered with other DO sequences, as well as some from Haiti. Conclusion In this snapshot of new HIV diagnoses in the DO, findings of high AIDS at diagnosis, particularly in heterosexuals, high TDR, more clustering in gay/bisexual younger individuals, and existing non-local-only transmission networks, should inform focused surveillance and prevention strategies to disrupt HIV transmission and improve care. Disclosures All Authors: No reported disclosures.

1257. Antiretroviral treatment failure in a prospective cohort of Persons Living with HIV in the Philippines

Abstract Background Widespread access to antiretrovirals has resulted in improved survival among PLHIV in resource-limited settings. In a previous study, ART failure in the Philippines after one year was found to be 10.3%. However, this was done as a cross-sectional study and did not capture dropouts or pre-existing drug resistance (PDR). Treatment failure, taking into account PDR, dropouts, and long-term viral suppression has not been studied. As part of a transmitted drug resistance (TDR) study, we prospectively followed patients and documented long-term viral suppression. Methods We enrolled 227 treatment-naïve PLHIV without TDR on Sanger-based sequencing and measured viral load (VL) every 6 months. VL “&amp;gt;”1000 copies/mL after initiation of treatment was considered treatment failure. An intention to treat analysis counting loss to follow-up as treatment failure was performed along with secondary analysis by subtype. Results Treatment failure at different time points are shown in Table 1. Of the 227 patients, 177 were subtype CRF01_AE, 30 were B, 14 were CRF01_AE/B recombinants, 2 were subtype CRF02_AG, 2 were CRF01_AE/B/F recombinants and one was an A1/D recombinant. Median VL was 295,000 copies/mL at baseline (range: 40 - 658,000 copies/mL). Seventeen PLHIV developed treatment failure over an observation time of up to 60 months, while 74 were lost to follow-up. Comparison between B and non-B subtypes showed a higher rate of failure among non-B subtypes (OR 2.868 95% CI 1.018 to 10.016 p=0.0380) at one year, but this was no longer significant at 24 months (p=0.1534) and 48 months (p=0.0716). Conclusion HIV viral suppression at one year of treatment is 65.6% in an intention to treat analysis. It is 63.4% at 24 months and 60.8% at 48 months. Excluding dropouts, viral suppression is 95.5%, 92.3%, and 89.0% at 12, 24, and 48 months, respectively. Non-B subtypes are more likely to fail than those with B subtypes in the first year of treatment. Loss to follow-up is a significant problem in the Philippines and needs to be addressed proactively in order to improve local efforts to reach the 90-90-90 thresholds of UNAIDS for control of HIV in the country. Disclosures Edsel Maurice Salvana, MD, MSD: Advisor/Consultant|MSD: Honoraria|Pfizer: Advisor/Consultant|Pfizer: Honoraria.

HIV-1 genetic diversity and transmitted drug resistance to integrase strand transfer inhibitors among recently diagnosed adults in Porto Alegre, South Brazil.

The HIV-1 genetic diversity and the presence of transmitted drug resistance mutations (TDRMs) against integrase strand transfer inhibitors (INSTIs) were assessed sequencing samples of antiretroviral (ARV)-naive HIV-1-infected individuals from South Brazil. Viral RNA from 42 ART-naive individuals was submitted to complete HIV-1 integrase gene amplification by RT-PCR and sequencing. Viral strains carrying TDRMs against INSTIs were not detected in the present study. However, the polymorphisms L74M and L74I were each observed in 4.8% of the individuals. These accessory mutations have been reported as putative causes of TDRMs in ART with raltegravir, but only when associated with additional major mutations. When submitted to HIV-1 subtyping, 50% were classified as subtype C, 21% as recombinant BC, 19% as subtype B, 4.8% as subtype F1 and 4.8% as recombinant CF1. All 42 ARV-naive individuals were apparently susceptible to INSTIs, included in the Brazilian therapeutic guideline since 2009. To the best of our knowledge, this is the first study to evaluate TDRMs against INSTIs in Brazil. The most prevalent HIV-1 subtypes were subtype C, followed by the recombinant BC and subtype B, which is in agreement with previous studies. However, the presence of subtype F1 and recombinant CF1 reported herein was not observed in previous studies.

Multidrug Resistance Tracing by Plasmid Profile Analysis and the Curing of Bacteria from Different Clinical Specimens

Human-pathogenic bacteria resistant to one or multiple antibiotics have dramatically increased worldwide in the past decades. These bacteria possess great danger, have become a global issue, and it is now impossible to avoid developing strategies for the restoration of treatment options against infections caused by them. This research aims at profiling plasmids of multidrug-resistant bacteria from various clinical specimens such as ear exudate, sputum, urethral swab, wound swab, urine from the catheter, urine, nasal swab, high vaginal swab, stool, eye swab, and blood at Chukwuemeka Odumegwu Ojukwu University Teaching Hospital, Awka, Anambra State, Nigeria. Our investigation used the agar diffusion method for susceptibility tests and identification of multidrug-resistant bacteria before plasmid extraction and gel electrophoresis. A plasmid curing test was performed with 10% sodium dodecyl sulphate. Of the 860 bacteria whose resistance profile was determined, only 42 were multidrug-resistant. These bacteria include Pseudomonas aeruginosa 16 (38.10%), Staphylococcus aureus 12 (28.57%), Escherichia coli 9 (21.43%), and Klebsiella pneumoniae 5(11.90%). The molecular weight of their plasmids ranges between 20.884 kbp and 187.50 kbp. As indicated by the plasmid bands, some bacteria had similar molecular weight while others had no plasmid. The bacterial pattern of the postcuring sensitivity test showed that the bacteria with plasmid bands were cured as they became susceptible to the drugs they were previously resistant to, while the bacteria without plasmid bands remained resistant to the antibiotics. This implies that the latter’s multidrug resistance is nonplasmid mediated. Our analyses highlight the relationship between plasmids and multidrug resistance as well as the role of plasmids in the transmission of drug resistance across bacteria. Thus, in order to lessen the burden that multidrug-resistant bacteria cause and to improve bacterial infections treatments, there should be continued surveillance and periodic research on antibiotic resistance patterns of bacteria from various clinical settings.

Low Prevalence of Transmitted HIV-1 Antiretroviral Resistance in Pregnant Women from Rio de Janeiro, Brazil

Background: HIV screening during antenatal care is being expanded in Brazil for early diagnosis of HIV-1 infection during pregnancy and prevention of vertical transmission. HIV genotyping in pregnant women is crucial to reduce the risk of vertical transmission in those carrying resistant strains and may also be used for Transmitted Drug Resistance (TDR) surveillance purpose. We evaluated prevalence and patterns of HIV-1 TDR and HIV subtype distribution in recently diagnosed ARV naïve pregnant women from Rio de Janeiro, Brazil. Methods: 299 blood samples of recently diagnosed HIV-1-infected pregnant women from four reference antenatal care public health units in Rio de Janeiro were consecutively collected and analyzed from 2005 to 2015.ViroseqTM (Abbott) and TrugeneTM HIV-1 Genotyping Systems (Siemens) were used for genotyping and the Standford Algorithm for Interpretation of HIV-1 Resistance for TDR and subtype identification. Results: The most prevalent HIV-1 subtype was the subtype B (77%), followed by subtype F (15%), BF recombinant forms (4%), subtype C (2%) and the recombinant forms: CRF02_AG, CRF31_BC and DF identified in one subject each. Overall, the TDR mutations was 11.7%, 2.7% associated to the Nucleoside Reverse Transcriptase Inhibitors (NRTIs) of the samples, 2.7% to Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) and 1% to Protease Inhibitors (PIs). Mutations associated with NRTI resistance were TAMs, F77L, M184V; associated with NNRTI resistance were K103N, Y188H and L100I and. mutations associated to PIs were D30N, M46I, and V82L. Conclusions: HIV-1 subtype B was the most prevalent subtype observed in our study. For the first time infections with the circulating recombinant forms CRF02_AG and CRF31_BC were described in a pregnant woman, suggesting the spread of African derived virus in Brazil and the introduction in Rio de Janeiro of the CRF31_BC coming from South Brazil. Our results strongly suggest the need of establishing a regular surveillance system for transmitted HIV-1 drug resistance in pregnant women in Brazil and its integration in antenatal care management policies for HIV-1 infected women should be considered.

The Effect of Pretreatment Potential Resistance to NNRTIs on Antiviral Therapy in Patients With HIV/AIDS

With the increasing coverage of antiretroviral therapy, concerns for the emergence and transmission of HIV drug resistance (HIVDR) are arising. HIVDR was divided into 5 levels: sensitive, potentially resistant, low resistant, intermediate resistant, and high resistant. Most of the articles on HIVDR involved low-level, intermediate-level, and high-level drug resistance to antiretroviral drug, and few articles deal with potential drug resistance. Treatment failure associated with the level of low-level, intermediate-level, and high-level resistance to antiretroviral drug has been reported. However, whether virological failure (VF) is related to potential resistance remains unclear. In this study, we aimed to describe the situation of potential resistance to antiretroviral drug and whether it is related to VF. We analyzed the demographic, behavioral information, medical history, and drug resistance-associated mutation data from subjects. Drug resistance mutations at baseline and time of failure in patients suffering VF were detected by using the Vela automated next-generation sequencing platform. The χ2 test or Fisher exact test and logistic regression were used to assess the risk factors that contribute to VF in the potential drug-resistant people. The prevalence of overall pretreatment drug resistance was 7.06% (233/3300), and the prevalence of pretreatment potential resistance was 8.79% (290/3300). All these patients with pretreatment potential first-line drugs resistance showed potential resistance to nonnucleoside reverse transcriptase inhibitors (NNRTIs), and some of them had potential drug resistance to NNRTIs and NRTIs or NNRTIs and PIs; among these patients, 94.71% (179/189) had V179 D/E mutations. The VF rate of first-line treatment for potentially resistant people is 17.99%. CD4+ T-cell count ≤200 cells/L at antiretroviral therapy initiation are risk factors for the failure of first-line treatment. The prevalence of potential drug resistance among individuals with HIV and the VF rate of first-line treatment for potential drug-resistant people were high. To better optimize clinical management, prevention, and control of HIV, attention should be devoted to the potential resistance of nonnucleoside drugs.

Prevalence of Drug Resistance and Genetic Transmission Networks Among Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome Patients with Antiretroviral Therapy Failure in Guangxi, China.

Prevalence of drug resistance (DR) challenges the epidemic control of human immunodeficiency virus (HIV)-1. However, little is known about DR among patients with antiretroviral therapy (ART) failure in Guangxi province, China. This cross-sectional study was aimed to investigate the prevalence of DR and the characteristics of DR sequences in the genetic transmission network among HIV-1 patients with ART failure in Guangxi. We enrolled 358 eligible patients between 2012 and 2018. Blood samples were subjected to reverse transcription polymerase chain reaction, followed by sequencing of the HIV-1 polymerase (pol) gene. An online subtyping tool and neighbor-joining phylogenetic tree were used to determine the genotype. HIV-TRACE tool was used to constructed transmission network with a pairwise genetic distance of 0.013. DR was analyzed using the Stanford University HIV Drug Resistance Database. We obtained 293 pol-sequences from participants; CRF01_AE (75.4%), CRF 08_BC (15.7%), and CRF07_BC (8.5%) were the main subtypes, and an A1 subtype was detected in Guangxi for the first time. The overall prevalence of DR was 32.4% (95/293). Among those with identified DR, 25.6% were against non-nucleoside analog reverse-transcriptase inhibitors (NNRTIs), 17.7% were against nucleoside analog reverse-transcriptase inhibitors (NRTIs), and 14.3% were against both NRTIs and NNRTIs. The common drug-resistant mutations were M184V (10.2%), K103N (10.6%) and V179D (6.1%). The patients located in the southern Guangxi [adjust odds ratio (AOR) = 10.87], or whose blood plasma were taken in 2017-2018 (AOR = 3.98) had an increased risk of DR. Of the CRF01_AE, CRF07_BC, and CRF08_BC sequences, 18.6%, 8.0%, and 13.0% fell into clusters, respectively. Nine (9.7%) sequences from patients with DR fell into three clusters. The largest cluster containing 11 individuals was the CRF01_AE subtype, 27.3% of whom were DR patients. Although the prevalence of DR among ART failure patients in Guangxi was at a low level, the continuous surveillance of DR in ART patients is necessary.

Profiles of Isoniazid and Rifampicin drug resistance conferring mutations in Mycobacterium tuberculosis among new and previously treated pulmonary tuberculosis cases from Kisumu County, Kenya

Mycobacterium tuberculosis infection is one of the leading causes of mortality and morbidity in developing countries and drug resistance remains a challenge. Drug resistance is hastened by point mutations in the bacilli genome and their frequencies vary geographically hence the need to understand regional specific patterns for early detection of mutant strains. In this cross sectional study, Sputum samples from pulmonary tuberculosis clinical suspects were collected to detect mutations in Mycobacterium tuberculosis that confers resistance to Isoniazid and rifampicin anti-anti tuberculosis drugs. Detection of mutations was done using GenoType MTBDRplus. Out of a sample of 256 from Tuberculosis clinical suspected cases, 145 were Mycobacterium tuberculosis bacilli confirmed out of which 32 (22%) were new Tuberculosis (TB) cases and 113(78%) retreatment. The total for isoniazid resistance was 9(6.2%), out of which 2(6.3%) were in new cases and 7(6.3%) in retreatment cases. Multi Drug Resistance (MDR) was 2(1.8%) and all in retreatment cases. Rifampicin resistance was 7(4.8%), 1 (3.1%) in new case and 6(5.3%) in retreatment. The MDR among Rifampicin Resistance(RR) was 28.6%. Low Isoniazid resilient strains had changes in the katG gene resulting to nucleotide change from A G C to A C C. Four rifampicin resistant isolates showed mutations at the rpoB gene with nucleotide change from C A C to T A C and a single isolate displayed mutation at the rpoB gene with nucleotide change from T C G to T T G. Same nucleotide change A G C to A C C from different patients in the same facility might be an indication of local transmission of drug resistance and greater variability of mutations observed in HIV positive and retreatment cases are possibilities of mutations acquired during treatment courses by repeated administration of the same anti-TB drugs.

Molecular Epidemiology of HIV-1 in Eastern Europe and Russia.

The HIV epidemic in Eastern Europe and Russia is large and not well-controlled. To describe the more recent molecular epidemiology of HIV-1, transmitted drug resistance, and the relationship between the epidemics in this region, we sequenced the protease and reverse transcriptase genes of HIV-1 from 812 people living with HIV from Ukraine (n = 191), Georgia (n = 201), and Russia (n = 420) before the initiation of antiretroviral therapy. In 190 Ukrainian patients, the integrase gene sequence was also determined. The most reported route of transmission was heterosexual contact, followed by intravenous drug use, and men having sex with men (MSM). Several pre-existing drug resistance mutations were found against non-nucleoside reverse transcriptase inhibitors (RTIs) (n = 103), protease inhibitors (n = 11), and nucleoside analogue RTIs (n = 12), mostly polymorphic mutations or revertants. In the integrase gene, four strains with accessory integrase strand transfer inhibitor mutations were identified. Sub-subtype A6 caused most of the infections (713/812; 87.8%) in all three countries, including in MSM. In contrast to earlier studies, no clear clusters related to the route of transmission were identified, indicating that, within the region, the exchange of viruses among the different risk groups may occur more often than earlier reported.

HIV-1 pretreatment drug resistance and genetic transmission network in the southwest border region of China

BackgroundHIV drug resistance increased with the widespread use of antiretroviral drugs, and posed great threat to antiretroviral therapy (ART). Pu’er Prefecture, lying in the southwest of Yunnan Province, China, borders Myanmar, Laos and Vietnam, is also the area where AIDS was discovered earlier, however, in which there has been no information on HIV drug resistance.MethodsA cross-sectional survey of pretreatment drug resistance (PDR) was conducted in Pu’er Prefecture in 2021. Partial pol gene sequences were obtained to analyze drug resistance and construct genetic transmission network. HIV drug resistance was analyzed using the Stanford University HIVdb algorithm.ResultsA total of 295 sequences were obtained, among which 11 HIV-1 strain types were detected and CRF08_BC (62.0%, 183/295) was the predominant one. Drug resistance mutations (DRMs) were detected in 42.4% (125/295) of the sequences. The prevalence of PDR to any antiretroviral drugs, nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs) were 10.8% (32/295), 9.5% (28/295), 1.0% (3/295) and 0.3% (1/295), respectively. The risk of PDR occurrence was higher among individuals with CRF01_AE strain types. HIV-1 molecular network was constructed, in which 56.0% (42/75) of links were transregional, and 54.7% (41/75) of links were associated with Lancang County. Among the sequences in the network, 36.8% (35/95) harbored DRMs, and 9.5% (9/95) were drug resistance strains. Furthermore, 8 clusters had shared DRM.ConclusionThe overall prevalence of PDR in this study was in a moderate level, but NNRTIs resistance was very approaching to the threshold of public response initiation. PDR was identified in the transmission network, and DRMs transmission was observed. These findings suggested that the consecutive PDR surveillance should be conducted in this region.

Men who have sex with men is the high-risk drug resistance population: A meta-analysis of HIV-1 drug resistance profiles and trends in China.

Except for the transmitted drug resistance (TDR)'s standard sampling and monitoring protocol, China's HIV-1 pretreatment drug resistance (PDR) and acquired drug resistance (ADR) results vary widely due to the studies' diverse background. This meta-analysis was conducted to comprehensively understand the drug resistance profiles of Chinese HIV/AIDS patients and compare the drug resistance differences among groups to provide a reference for the further improvement of treatment protocols. Data sources for this study were WANFANG, VIP, CNKI, SinoMed, PubMed and Web of Science databases from January 1, 2010 to January 13, 2022. Data extracted from the literature were analyzed by R and Stata to evaluate the profile and changing trend of drug resistance in Chinese HIV/AIDS patients. One hundred twenty-one literature were included. The combined PDR and ADR in the Chinese HIV/AIDS patients was 5.56% (95% CI: 4.77%-6.41%) and 51.33% (95% CI: 47.57%-55.38%), respectively. The time trend analysis shows the upward trend of PDR. There were significate differences in ADR among different sample sources, the ADR in the central region were higher than those in all other regions. The PDR in men who have sex with men (MSM) was lower the whole population, while the MSM's ADR was much higher than whole population. PDR in China showed an upward trend and exceeded the 5% warning line but is still at a low level worldwide. ADR is stable and below the middle level globally; the comprehensively promoted free ART in China still has lasting effects. MSM is the high-risk drug resistance population, targeted treatment strategies should be used.

Molecular Epidemiology and Trends in HIV-1 Transmitted Drug Resistance in Mozambique 1999-2018.

HIV drug resistance (HIVDR) can become a public health concern, especially in low- and middle-income countries where genotypic testing for people initiating antiretroviral therapy (ART) is not available. For first-line regimens to remain effective, levels of transmitted drug resistance (TDR) need to be monitored over time. To determine the temporal trends of TDR in Mozambique, a search for studies in PubMed and sequences in GenBank was performed. Only studies covering the pol region that described HIVDR and genetic diversity from treatment naïve patients were included. A dataset from seven published studies and one novel unpublished study conducted between 1999 and 2018 were included. The Calibrated Population Resistance tool (CPR) and REGA HIV-1 Subtyping Tool version 3 for sequences pooled by sampling year were used to determine resistance mutations and subtypes, respectively. The prevalence of HIVDR amongst treatment-naïve individuals increased over time, reaching 14.4% in 2018. The increase was most prominent for non-nucleoside reverse transcriptase inhibitors (NNRTIs), reaching 12.7% in 2018. Subtype C was predominant in all regions, but a higher genetic variability (19% non-subtype C) was observed in the north region of Mozambique. These findings confirm a higher diversity of HIV in the north of the country and an increased prevalence of NNRTI resistance among treatment naïve individuals over time.