{"doi":"10.58395/pipd.v48i1.29","title":"ISONIAZID - MONORESISTANT TUBERCULOSIS IN BULGARIA","abstract":"<jats:p>Background. Isoniazid is a common drug in the treatment regimens for TB infection. Monoisoniazid resistance reduces the probability of a successful treatment outcome and increases the risk of acquiring additional drug resistance.&#x0D;\nMaterial and methods. For the period 2015-2016 a total of 36 TB cases were confirmed in NRL TB, Sofia, as isoniazid-monoresistant Mycobacterium tuberculosis complex. Minimum inhibitory concentration testing for isoniazid was conducted with BАСТЕС MGIT 960 System in the following concentrations of the drug: 0.1 μg/ml, 0.15μg/ml, 0.2μg/ml, 0.3μg/ml, 0.4μg/ml. Molecular testing was performed with GenoType ® MTBDRplus in order to detect the most common mutations associated with resistance to isoniazid.&#x0D;\nResults. Only 25% of the tested M. tuberculosis complex isolates with phenotypic isoniazid monoresistance had the S315T1 mutation in katG; all isolates were with MIC over 0.4 μg/ml. C15T in the promoter region of inhA was detected in 22.22% of cases and only 1 of them showed MIC below 0.4 μg/ml. No mutations were detected in nearly half of the cases (n=19, 52.78%) and most of these isolates were with lower MIC values (n=12). Conclusion. The rapid testing with GenoType ® MTBDRplus can be used as a screening procedure indicating whether further examination of isoniazid MIC is relevant in resistant M. tuberculosis and whether higher doses could be considered.</jats:p>","journal":"PROBLEMS of Infectious and Parasitic Diseases","year":2020,"id":633419,"datarank":0.20794415416798362,"base_score":1.3862943611198906,"endowment":1.3862943611198906,"self_citation_contribution":0.20794415416798362,"citation_network_contribution":0.0,"self_endowment_contribution":0.20794415416798362,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":3,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1642239,"name":"Ana Baykova","orcid":null,"position":1,"is_corresponding":false},{"id":1642240,"name":"Yuliana Atanasova","orcid":null,"position":2,"is_corresponding":false},{"id":1642241,"name":"Yana Todorova","orcid":null,"position":3,"is_corresponding":false},{"id":1642242,"name":"Elizabeta Bachiyska","orcid":null,"position":4,"is_corresponding":false},{"id":1642238,"name":"Stanislava Yordanova","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"ISONIAZID - MONORESISTANT TUBERCULOSIS IN BULGARIA","abstract":"<jats:p>Background. Isoniazid is a common drug in the treatment regimens for TB infection. Monoisoniazid resistance reduces the probability of a successful treatment outcome and increases the risk of acquiring additional drug resistance.&#x0D;\nMaterial and methods. For the period 2015-2016 a total of 36 TB cases were confirmed in NRL TB, Sofia, as isoniazid-monoresistant Mycobacterium tuberculosis complex. Minimum inhibitory concentration testing for isoniazid was conducted with BАСТЕС MGIT 960 System in the following concentrations of the drug: 0.1 μg/ml, 0.15μg/ml, 0.2μg/ml, 0.3μg/ml, 0.4μg/ml. Molecular testing was performed with GenoType ® MTBDRplus in order to detect the most common mutations associated with resistance to isoniazid.&#x0D;\nResults. Only 25% of the tested M. tuberculosis complex isolates with phenotypic isoniazid monoresistance had the S315T1 mutation in katG; all isolates were with MIC over 0.4 μg/ml. C15T in the promoter region of inhA was detected in 22.22% of cases and only 1 of them showed MIC below 0.4 μg/ml. No mutations were detected in nearly half of the cases (n=19, 52.78%) and most of these isolates were with lower MIC values (n=12). Conclusion. The rapid testing with GenoType ® MTBDRplus can be used as a screening procedure indicating whether further examination of isoniazid MIC is relevant in resistant M. tuberculosis and whether higher doses could be considered.</jats:p>","is_dataset_classified":null,"base_score":1.3862943611198906,"endowment":1.3862943611198906,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"19767382","pmcid":null,"openalex_id":"https://openalex.org/W3043092866","authors":[],"funders":[],"total_grants":0,"fwci":0.0725,"citation_percentile":0.48989565,"influential_citations":0,"citation_trend":[{"year":2022,"count":3}],"oa_status":"gold","license":"cc-by","oa_locations":[{"url":"https://pipd.ncipd.org/index.php/pipd/article/download/29/48-1-3_isoniazid-monoresistant_tuberculosis_in_bulgaria","host_type":"journal"},{"url":"https://pipd.ncipd.org/index.php/pipd/article/download/29/48-1-3_isoniazid-monoresistant_tuberculosis_in_bulgaria","host_type":"publisher"},{"url":"https://doi.org/10.58395/pipd.v48i1.29","host_type":"journal"},{"url":"https://doaj.org/article/6755af1f3b6f47368b6aa10a23a1ffc0","host_type":"repository"},{"url":"https://pipd.ncipd.org/index.php/pipd/article/view/29","host_type":""}],"fields_of_study":["Tuberculosis Research and Epidemiology","Mycobacterium research and diagnosis","Diagnosis and treatment of tuberculosis"],"mesh_terms":[],"keywords":["Isoniazid","INHA","Tuberculosis","Mycobacterium tuberculosis","Genotype","Drug resistance","Minimum inhibitory concentration","Medicine","Microbiology","Virology","Biology","Antibiotics","Genetics","Pathology","Gene"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Good health and well-being"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-06T12:01:21.801772Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}