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Emerging Infectious Diseases Feb 2021Multidrug resistance has been detected in the animal and zoonotic human pathogen Rhodococcus equi after mass macrolide/rifampin antibioprophylaxis in endemically...
Multidrug resistance has been detected in the animal and zoonotic human pathogen Rhodococcus equi after mass macrolide/rifampin antibioprophylaxis in endemically affected equine farms in the United States. Multidrug-resistant (MDR) R. equi emerged upon acquisition of pRERm46, a conjugative plasmid conferring resistance to macrolides, lincosamides, streptogramins, and, as we describe, tetracycline. Phylogenomic analyses indicate that the increasing prevalence of MDR R. equi since it was first documented in 2002 is caused by a clone, R. equi 2287, attributable to coselection of pRErm46 with a chromosomal rpoB mutation driven by macrolide/rifampin therapy. pRErm46 spillover to other R. equi genotypes has given rise to a novel MDR clone, G2016, associated with a distinct rpoB mutation. Our findings illustrate that overuse of antimicrobial prophylaxis in animals can generate MDR pathogens with zoonotic potential. MDR R. equi and pRErm46-mediated resistance are currently disseminating in the United States and are likely to spread internationally through horse movements.
Topics: Actinomycetales Infections; Animals; Anti-Bacterial Agents; Drug Resistance, Bacterial; Horse Diseases; Horses; Macrolides; Rhodococcus; Rhodococcus equi; United States
PubMed: 33496218
DOI: 10.3201/eid2702.203030 -
Antimicrobial Agents and Chemotherapy Apr 2022While the use of long-term macrolide therapy to prevent exacerbations in chronic respiratory diseases is widespread, its impact on the oropharyngeal microbiota and... (Randomized Controlled Trial)
Randomized Controlled Trial
Assessment of Long-Term Macrolide Exposure on the Oropharyngeal Microbiome and Macrolide Resistance in Healthy Adults and Consequences for Onward Transmission of Resistance.
While the use of long-term macrolide therapy to prevent exacerbations in chronic respiratory diseases is widespread, its impact on the oropharyngeal microbiota and macrolide resistance, and the potential for onward transmission of resistance to close contacts are poorly understood. We determined the effects of long-term exposure to azithromycin or erythromycin on phenotypic and genotypic macrolide resistance within the oropharyngeal microbiome of healthy adults and their close contacts in a randomized, single-blinded, parallel-group trial of 4 weeks of twice-daily oral 400 mg erythromycin ethylsuccinate or twice-daily oral 125 mg azithromycin. Using oropharyngeal swabs collected from 20 index healthy adults and 20 paired close contacts, the oropharyngeal microbial composition and macrolide resistance in streptococci were assessed by 16S rRNA sequencing and antibiotic susceptibility testing of oropharyngeal cultures, respectively, at baseline and weeks 4 and 8 (washout). Targeted quantitative PCR of antibiotic resistance genes was performed to evaluate paired changes in resistance gene levels in index patients and close contacts and to relate the potential transmission of antibiotic resistance. Neither azithromycin nor erythromycin altered oropharyngeal microbiota characteristics significantly. Proportional macrolide resistance in oropharyngeal streptococci increased with both erythromycin and azithromycin, remaining above baseline levels for the azithromycin group at washout. Levels of resistance genes increased significantly with azithromycin[(B) and ] and erythromycin (), returning to baseline levels at washout only for the erythromycin group. We found no evidence of onward transmission of resistance to close contacts, as indicated by the lack of concomitant changes in resistance gene levels detected in close contacts. (This study has been registered with the Australian and New Zealand Clinical Trials Registry under identifier ACTRN12617000278336.).
Topics: Adult; Anti-Bacterial Agents; Australia; Azithromycin; Drug Resistance, Bacterial; Erythromycin; Humans; Macrolides; Microbiota; RNA, Ribosomal, 16S; Streptococcus
PubMed: 35293783
DOI: 10.1128/aac.02246-21 -
Rheumatology International Dec 2022Colchicine is increasingly used as the number of potential indications expands. However, it also has a narrow therapeutic index that is associated with bothersome to...
Colchicine is increasingly used as the number of potential indications expands. However, it also has a narrow therapeutic index that is associated with bothersome to severe side effects. When concomitantly use with medications inhibiting its metabolism, higher plasma levels will result and increase likelihood of colchicine toxicity. We conducted a cohort study using electronic health records comparing encounters with colchicine plus a macrolide and colchicine with an antibiotic non-macrolide. We assessed the relationship between the two groups using adjusted multivariate logistic regression models and the risk of rhabdomyolysis, pancytopenia, muscular weakness, heart failure, acute hepatic failure and death. 12670 patients on colchicine plus an antibiotic non-macrolide were compared to 2199 patients exposed to colchicine plus a macrolide. Patients exposed to colchicine and a macrolide were majority men (n = 1329, 60.4%) and white (n = 1485, 67.5%) in their late sixties (mean age in years 68.4, SD 15.6). Heart failure was more frequent in the colchicine plus a macrolide cohort (n = 402, 18.3%) vs the colchicine non-macrolide one (n = 1153, 9.1%) (p < 0.0001) and also had a higher mortality rate [(85 (3.87%) vs 289 (2.28%), p < 0.0001 macrolides vs non-macrolides cohorts, respectively]. When the sample was limited to individuals exposed to either clarithromycin or erythromycin and colchicine, the adjusted OR for acute hepatic failure was 2.47 (95% CI 1.04-5.91) and 2.06 for death (95% CI 1.07-3.97). There is a significant increase in the risk of hepatic failure and mortality when colchicine is concomitantly administered with a macrolide. Colchicine should not be used concomitantly with these antibiotics or should be temporarily discontinued to avoid toxic levels of colchicine.
Topics: Anti-Bacterial Agents; Clarithromycin; Cohort Studies; Colchicine; Erythromycin; Humans; Macrolides; Male
PubMed: 36104598
DOI: 10.1007/s00296-022-05201-5 -
Bioscience Trends May 2020The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic that has developed in late 2019 and 2020 is a serious threat to human health. With no vaccines...
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic that has developed in late 2019 and 2020 is a serious threat to human health. With no vaccines or drugs approved for prevention and treatment until now, all efforts at drug design and/or clinical trials of already approved drugs are worthy and creditable. Using structure-based drug selection for identification of SARS-CoV-2 protease inhibitors, old drugs such as macrolides (MAC) were predicted to be effective for COVID-19. Lately, the anti-viral effects of macrolides have attracted considerable attention. Very recently, hydroxychloroquine in combination with azithromycin treatment was reported to be effective for COVID-19. We believe that treatments with macrolides alone or in combination with other drugs are promising and open the possibility of an international strategy to fight this emerging viral infection.
Topics: Antiviral Agents; Betacoronavirus; COVID-19; Coronavirus Infections; Humans; Macrolides; Pandemics; Pneumonia, Viral; Protease Inhibitors; SARS-CoV-2; Structure-Activity Relationship; COVID-19 Drug Treatment
PubMed: 32249257
DOI: 10.5582/bst.2020.03058 -
Nature Communications Mar 2021Pharmacological inhibition of vacuolar-type H-ATPase (V-ATPase) by its specific inhibitor can abrogate tumor metastasis, prevent autophagy, and reduce cellular signaling...
Pharmacological inhibition of vacuolar-type H-ATPase (V-ATPase) by its specific inhibitor can abrogate tumor metastasis, prevent autophagy, and reduce cellular signaling responses. Bafilomycin A1, a member of macrolide antibiotics and an autophagy inhibitor, serves as a specific and potent V-ATPases inhibitor. Although there are many V-ATPase structures reported, the molecular basis of specific inhibitors on V-ATPase remains unknown. Here, we report the cryo-EM structure of bafilomycin A1 bound intact bovine V-ATPase at an overall resolution of 3.6-Å. The structure reveals six bafilomycin A1 molecules bound to the c-ring. One bafilomycin A1 molecule engages with two c subunits and disrupts the interactions between the c-ring and subunit a, thereby preventing proton translocation. Structural and sequence analyses demonstrate that the bafilomycin A1-binding residues are conserved in yeast and mammalian species and the 7'-hydroxyl group of bafilomycin A1 acts as a unique feature recognized by subunit c.
Topics: Amino Acid Sequence; Animals; Binding Sites; Biocatalysis; Cattle; Cryoelectron Microscopy; Enzyme Inhibitors; Macrolides; Models, Molecular; Molecular Structure; Protein Binding; Protein Domains; Sequence Homology, Amino Acid; Vacuolar Proton-Translocating ATPases
PubMed: 33741963
DOI: 10.1038/s41467-021-22111-5 -
Microbial Genomics Sep 2023() is a leading vaccine-preventable cause of childhood invasive disease. Nigeria has the second highest pneumococcal disease burden globally, with an estimated...
() is a leading vaccine-preventable cause of childhood invasive disease. Nigeria has the second highest pneumococcal disease burden globally, with an estimated ~49 000 child deaths caused by pneumococcal infections each year. Ten-valent pneumococcal conjugate vaccine (GSK; PCV10) was introduced in December 2014 in a phased approach. However, few studies have characterized the disease-causing pneumococci from Nigeria. This study assessed the prevalence of serotypes, antibiotic susceptibility and genomic lineages using whole genome sequencing and identified lineages that could potentially escape PCV10 (GSK). We also investigated the potential differences in pneumococcal lineage features between children with and without sickle cell disease. A collection of 192 disease-causing pneumococcal isolates was obtained from Kano (=189) and Abuja (=3) states, Nigeria, between 1 January 2014 and 31 May 2018. The majority (99 %, 190/192) of specimens were recovered from children aged 5 years or under. Among them, 37 children had confirmed or traits of sickle cell disease. Our findings identified 25 serotypes expressed by 43 Global Pneumococcal Sequence Clusters (GPSCs) and 85 sequence types (STs). The most common serotypes were 14 (18 %, =35), 6B (16 %, =31), 1 (9 %, =17), 5 (9 %, =17) and 6A (9 %, =17); all except serotype 6A are included in PCV10 (GSK). PCV10 (SII; PNEUMOSIL) and PCV13 formulations include serotypes 6A and 19A which would increase the overall coverage from 67 % by PCV10 (GSK) to 78 and 82 %, respectively. The pneumococcal lineages were a mix of globally spreading and unique local lineages. Following the use of PCV10 (GSK), GPSC5 expressing serotype 6A, GPSC10 (19A), GPSC26 (12F and 46) and GPSC627 (9L) are non-vaccine type lineages that could persist and potentially expand under vaccine-selective pressure. Approximately half (52 %, 99/192) of the pneumococcal isolates were resistant to the first-line antibiotic penicillin and 44 % (85/192) were multidrug-resistant. Erythromycin resistance was very low (2 %, 3/192). There was no significant difference in clinical manifestation, serotype prevalence or antibiotic resistance between children with and without traits of or confirmed sickle cell disease. In summary, our findings show that a high percentage of the pneumococcal disease were caused by the serotypes that are covered by currently available vaccines. Given the low prevalence of resistance, macrolide antibiotics, such as erythromycin, should be considered as an option to treat pneumococcal disease in Nigeria. However, appropriate use of macrolide antibiotics should be vigilantly monitored to prevent the potential increase in macrolide resistance.
Topics: Humans; Child; Streptococcus pneumoniae; Nigeria; Anti-Bacterial Agents; Drug Resistance, Bacterial; Macrolides; Pneumococcal Infections; Erythromycin; Anemia, Sickle Cell; Protein Synthesis Inhibitors
PubMed: 37712828
DOI: 10.1099/mgen.0.001094 -
Scientific Reports Mar 2024This study aimed to investigate differences in clinical characteristics and laboratory findings between children infected with Macrolide-Sensitive Mycoplasma pneumoniae... (Observational Study)
Observational Study
This study aimed to investigate differences in clinical characteristics and laboratory findings between children infected with Macrolide-Sensitive Mycoplasma pneumoniae (MSMP) and Macrolide-Resistant Mycoplasma pneumoniae (MRMP). Additionally, the research sought to identify laboratory markers for rapidly distinguishing refractory Mycoplasma pneumoniae pneumonia (RMPP) from ordinary Mycoplasma pneumoniae pneumonia (OMPP). In total, 265 Mycoplasma pneumoniae (MP) patients were included, with MRMP identified by specific point mutations in domain V of the 23S rRNA gene. A retrospective analysis compared the clinical courses and laboratory data, revealing that MRMP patients experienced prolonged febrile days (P = 0.004), elevated CRP levels (P < 0.001), and higher MP DNA loads than MSMP patients (P = 0.037). Based on clinical symptoms, MRMP was divided into RMPP (n = 56) and OMPP (n = 70), with RMPP demonstrating significantly increased IL-18, community-acquired respiratory distress syndrome (CARDS) toxins in nasopharyngeal aspirate, and serum CRP levels (P < 0.001; P = 0.006; P < 0.001). In conclusion, timely recognition of RMPP is crucial for enhancing prognosis. The identification of MRMP, coupled with proinflammatory cytokines such as IL-18, CARDS toxins, and CRP, emerges as promising markers with the potential to contribute significantly to diagnostic accuracy and prognosis assessment.
Topics: Child; Humans; Anti-Bacterial Agents; China; Drug Resistance, Bacterial; Interleukin-18; Macrolides; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Respiratory Distress Syndrome; Retrospective Studies
PubMed: 38453960
DOI: 10.1038/s41598-024-55311-2 -
The Journal of Antimicrobial... Sep 2021Macrolides are widely prescribed antibiotics for many different indications. However, there are concerns about adverse effects such as ototoxicity.
BACKGROUND
Macrolides are widely prescribed antibiotics for many different indications. However, there are concerns about adverse effects such as ototoxicity.
OBJECTIVES
To investigate whether macrolide use is associated with tinnitus and hearing loss in the general population.
METHODS
Cross-sectional (n = 4286) and longitudinal (n = 636) analyses were performed within the population-based Rotterdam Study. We investigated with multivariable logistic regression models the association between macrolides and tinnitus, and with multivariable linear regression models the association between macrolides and two different hearing thresholds (both ears, averaged over 0.25, 0.5, 1, 2, 4 and 8 kHz and 2, 4 and 8 kHz). Both regression models were adjusted for age, sex, systolic blood pressure, alcohol, smoking, BMI, diabetes, education level, estimated glomerular filtration rate and other ototoxic or tinnitus-generating drugs. Cumulative exposure to macrolides was categorized according to the number of dispensed DDDs and duration of action.
RESULTS
In the fully adjusted model, ever use of macrolides was associated with a 25% higher likelihood of prevalent tinnitus (OR = 1.25; 95% CI 1.07-1.46). This association was more prominent in participants with a cumulative dose of more than 14 DDDs and among users of intermediate- or long-acting macrolides. Macrolide use in between both assessments was associated with more than a 2-fold increased risk on incident tinnitus. No general association between macrolides and hearing loss was observed. A borderline significant higher hearing threshold in very recent users (≤3 weeks) was found.
CONCLUSIONS
Macrolide use was significantly associated with both prevalent and incident tinnitus. Macrolide-associated tinnitus was likely cumulative dose-dependent.
Topics: Anti-Bacterial Agents; Cross-Sectional Studies; Hearing Loss; Humans; Longitudinal Studies; Macrolides; Tinnitus
PubMed: 34312676
DOI: 10.1093/jac/dkab232 -
Proceedings of the National Academy of... Dec 2022Although lacking an adaptive immune system and often living in habitats with dense and diverse bacterial populations, marine invertebrates thrive in the presence of...
Although lacking an adaptive immune system and often living in habitats with dense and diverse bacterial populations, marine invertebrates thrive in the presence of potentially challenging microbial pathogens. However, the mechanisms underlying this resistance remain largely unexplored and promise to reveal novel strategies of microbial resistance. Here, we provide evidence that a mud-dwelling clam, s, synthesizes, stores, and secretes the antibiotic erythromycin. Liquid chromatography coupled with mass spectrometry, immunocytochemistry, fluorescence in situ hybridization, RNA interference, and enzyme-linked immunosorbent assay revealed that this potent macrolide antimicrobial, thought to be synthesized only by microorganisms, is produced by specific mucus-rich cells beneath the clam's mantle epithelium, which interfaces directly with the bacteria-rich environment. The antibacterial activity was confirmed by bacteriostatic assay. Genetic, ontogenetic, phylogenetic and genomic evidence, including genotypic segregation ratios in a family of full siblings, gene expression in clam larvae, phylogenetic tree, and synteny conservation in the related genome region further revealed that the genes responsible for erythromycin production are of animal origin. The detection of this antibiotic in another clam species showed that the production of this macrolide is not exclusive to and may be a common strategy among marine invertebrates. The finding of erythromycin production by a marine invertebrate offers a striking example of convergent evolution in secondary metabolite synthesis between the animal and bacterial domains. These findings open the possibility of engineering-animal tissues for the localized production of an antibacterial secondary metabolite.
Topics: Animals; Erythromycin; Phylogeny; In Situ Hybridization, Fluorescence; Bivalvia; Anti-Bacterial Agents; Macrolides
PubMed: 36442100
DOI: 10.1073/pnas.2214150119 -
Clinical Reviews in Allergy & Immunology Jun 2022While fluoroquinolones, vancomycin, macrolides, and tetracyclines are generally safe antibiotics, they can induce both immediate and delayed hypersensitivity reactions... (Review)
Review
While fluoroquinolones, vancomycin, macrolides, and tetracyclines are generally safe antibiotics, they can induce both immediate and delayed hypersensitivity reactions (HSRs). Historically, less has been published on allergies to these antibiotics compared to beta lactams, but the prevalence of non-beta lactam HSRs is increasing. To fluoroquinolones, immediate HSRs are more common than delayed reactions. Both IgE and non-IgE mechanisms, such as the mast cell receptor Mas-related G protein-coupled receptor X2 (MRGPRX2), have been implicated in fluoroquinolone-induced anaphylaxis. Skin testing for fluoroquinolones is controversial, and the gold standard for diagnosis is a graded dose challenge. To vancomycin, the most common reaction is vancomycin infusion reaction (previously called "red man syndrome"), which is caused by infusion rate-dependent direct mast cell degranulation. Severity can range from flushing and pruritis to angioedema, bronchospasm, and hypotension that mimic type I HSRs. MRGPRX2 has been implicated in vancomycin infusion reactions. IgE-mediated HSRs to vancomycin are rare. Vancomycin skin testing yields high false positive rates. Thus, direct provocation challenge with slower infusion rate and/or antihistamine pre-treatment is preferred if symptoms are mild to moderate, and desensitization can be considered if symptoms are severe. To tetracyclines, non-IgE-mediated and delayed HSRs predominate with cutaneous reactions being the most common. There is no standardized skin testing for tetracyclines, and avoidance is generally recommended after a severe reaction because of the paucity of data for testing. Graded dose challenges and desensitizations can be considered for alternative or index tetracyclines if there are no alternatives. With macrolides, urticaria/angioedema is the most common immediate HSR, and rash is the most common delayed HSR. The predictive value for skin testing to macrolides is similarly poorly defined. In general, HSRs to fluroquinolones, vancomycin, macrolides, and tetracyclines are challenging to diagnose given the lack of validated skin testing and in vitro testing. Direct provocation challenge remains the gold standard for diagnosis, but the benefits of confirming an allergy may not outweigh the risk of a severe reaction. Skin testing, direct provocation challenge, and/or desensitization to the index non-beta lactam antibiotic or alternatives in its class may be reasonable approaches depending on the clinical context and patient preferences.
Topics: Angioedema; Anti-Bacterial Agents; Drug Hypersensitivity; Fluoroquinolones; Humans; Hypersensitivity, Immediate; Immunoglobulin E; Macrolides; Nerve Tissue Proteins; Receptors, G-Protein-Coupled; Receptors, Neuropeptide; Tetracyclines; Vancomycin
PubMed: 35092578
DOI: 10.1007/s12016-021-08919-5