Purpose: IS6110 restriction fragment length polymorphism (RFLP) analysis is widely used for molecular epidemiological studies of tuberculosis. Role of spoligotyping and Fluorescent Amplified Fragment Length Polymorphism (FAFLP) was studied in low-copy number IS6110 strains of Mycobacterium tuberculosis complex (Mtbc).
Methods: The study isolates included 70 strains of Mtbc collected from different regions of India.
The predominant strains from India belong to Central-Asian (CAS) and the East-African-Indian (EAI) clade of Mycobacterium tuberculosis. The two clades have also been shown to be geographically partitioned. The study of such strains may help to understand the characteristics that make M.
View Article and Find Full Text PDFMicroscopy is the mainstay of laboratory diagnosis of tuberculosis especially in resource poor countries. The World Health Organization has also recommended microscopy as the mainstay of diagnosis for directly observed treatment, short course. Using DNA extracts from Ziehl-Neelsen (ZN)-stained sputum smears, a single-tube nested polymerase chain reaction was optimized to confirm Mycobacterium tuberculosis complex and detect rifampin (RIF) resistance by sequencing, using a combination of novel (rpoB47 and rpoB158) and previously described (rpoB105 and rpoB293) primers.
View Article and Find Full Text PDFSpoligotyping was performed on 540 Mycobacterium tuberculosis isolates in order to evaluate the genetic biodiversity of tubercle bacilli in India. One hundred and forty seven patterns were unique and 393 were grouped in 48 clusters. Comparison with an international spoligotype database showed that the most predominant clades among tuberculosis (TB) isolates were Central Asian (CAS) and East-African Indian (EAI) with shared-types (ST) ST26 and ST11 alone being responsible for 34% of all TB cases.
View Article and Find Full Text PDFFever of unknown origin (FUO) poses a diagnostic challenge to the clinicians, with a differential diagnosis as varied as neoplastic and infectious diseases. In developing countries, the infectious causes are responsible for more cases of FUO, with tuberculosis as one of the main causes of classic FUO. Disseminated tuberculosis with negative pulmonary findings is a diagnostic problem.
View Article and Find Full Text PDFSpoligotyping was applied to old (5-11 years) Ziehl-Neelsen (ZN)-stained smears for strain identification and differentiation and to predict the utility of the technique in epidemiological studies. Among 57 DNA samples extracted from ZN slides lying stored at room temperature, 93% (53) amplification was achieved for mpt64 gene. Spoligopatterns were generated from 77.
View Article and Find Full Text PDFDrug resistance in tuberculosis is a significant problem in countries endemic for tuberculosis. A sensitive, specific, and high-throughput reverse line blot assay (RLBA) for the detection of genotypic resistance to rifampicin (RIF) was designed and evaluated. DNA sequencing done for 72 resistant isolates from Delhi, for baseline data, showed mutations within the rpoB core region in all RIF-resistant strains.
View Article and Find Full Text PDFMulti drug-resistant Mycobacterium tuberculosis (MDR TB) has been well studied in outbreaks in settings of low endemicity in developed countries. However, the characteristics of MDR TB in the community with high endemicity such as India have not been well investigated. Mutations in the 81-bp rifampicin resistance-determining region of the rpoB gene were analyzed by DNA sequencing of 187 M.
View Article and Find Full Text PDFHistopathological and mycobacteriological examinations have limited utility in the diagnosis of genital tuberculosis. In this double-blind study, 61 samples, consisting of endometrial aspirates (EAs), endometrial biopsies (EBs) and fluid from the pouch of Douglas (POD), from 25 women suffering from infertility were investigated for the presence of the mpt64 gene of Mycobacterium tuberculosis by PCR and correlated with laparoscopic findings. PCR demonstrated M.
View Article and Find Full Text PDFOne hundred five Mycobacterium tuberculosis clinical isolates from the Delhi area were typed by spoligotyping; 45 patterns were identified. Comparison with an international spoligotype database showed type 26, Delhi type (22%), type 54 (12%), and type 1, Beijing type (8%), as the most common. Eighteen spoligotypes did not match any existing database pattern.
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