Efficacy Of Line Probe Assay In Detection Of Drug-Resistant Pulmonary Tuberculosis In Comparison With GeneXpert And Phenotypic Methods In Iran And Genetic Analysis Of Isolates By MIRU-VNTR

Hossein Kazemian; Jalil Kardan-Yamchi; Abbas Bahador; Shadi Khonsari; Mahshid Nasehi; Gholamreza Hamzehloo; Farzam Vaziri; Mohammad Reza Salehi; Mohammad Mehdi Feizabadi

doi:10.2147/IDR.S222905

Efficacy Of Line Probe Assay In Detection Of Drug-Resistant Pulmonary Tuberculosis In Comparison With GeneXpert And Phenotypic Methods In Iran And Genetic Analysis Of Isolates By MIRU-VNTR

Infect Drug Resist. 2019 Nov 15:12:3585-3593. doi: 10.2147/IDR.S222905. eCollection 2019.

Authors

Hossein Kazemian¹, Jalil Kardan-Yamchi², Abbas Bahador¹, Shadi Khonsari³, Mahshid Nasehi⁴, Gholamreza Hamzehloo⁵, Farzam Vaziri⁶, Mohammad Reza Salehi⁷, Mohammad Mehdi Feizabadi^{1

8}

Affiliations

¹ Department of Medical Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
² Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
³ Natural Science Department, School of Science and Technology, Middlesex University, London, UK.
⁴ Department of Epidemiology and Biostatistics, Iran University of Medical Sciences, Tehran, Iran.
⁵ Tehran Regional Reference Laboratory for Tuberculosis, Tehran, Iran.
⁶ Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran.
⁷ Department of Infectious Disease, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.
⁸ Thoracic Research Center, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.

Abstract

Background: Successful treatment of tuberculosis depends on early diagnosis and use of appropriate drug susceptibility testing in a timely manner. In the present study, LPA efficacy was assayed in detection and drug susceptibility testing of pulmonary tuberculosis in comparison to available methods in Iran and phylogenetic analyses of isolated cases carried out by MIRU-VNTR.

Methods: This study was conducted at the Tehran Regional Reference Laboratory for Tuberculosis. All sputum specimens were subjected to smear, culture, and drug susceptibility testing (DST), GeneXpert, and LPA. Finally, 15-locus-based MIRU-VNTR was used for molecular genotyping.

Results: From a total of 920 sputum specimens, 6.08% (n=56) were identified as MTBC by culture, 6.8% (n=63) by GeneXpert, and 6.5% (n=60) by LPA. Phenotype DST and LPA methods confirmed the resistance of 4 and 14 specimens to rifampin (RIF) and isoniazid (INH); two cases were considered as multidrug-resistant (MDR). Using GeneXpert, four cases were identified as RIF-resistant. Based on LPA results, inhA and katG mutations were detected in 100% and 21.4% of INH-resistant cases, respectively. All 56 culture positive Mycobacterium tuberculosis isolates were placed in 29 different clusters using MIRU-VNTR genotyping. Two MDR-TB, 2 RIF mono-resistant, and 12 INH mono-resistant cases were placed in different clusters.

Conclusion: LPA is an appropriate method for early detection and accurate diagnosis of TB and drug-resistant cases that makes it possible to distinguish INH mono-resistant cases from MDR cases in Iran.

Keywords: drug resistance; early diagnosis; line probe assay; mutation; tuberculosis.