Phenotypic and Genotypic Analysis of Anti-Tuberculosis Drug Resistance in Mycobacterium tuberculosis Isolates in Myanmar

BACKGROUND: Tuberculosis (TB) is one of the most serious health problems in Myanmar. Because TB drug resistance is associated with genetic mutation(s) relevant to responses to each drug, genotypic methods for detecting these mutations have been proposed to overcome the limitations of classic phenotypic drug susceptibility testing (DST). We explored the current estimates of drug-resistant TB and evaluated the usefulness of genotypic DST in Myanmar. METHODS: We determined the drug susceptibility of Mycobacterium tuberculosis isolated from sputum smear-positive patients with newly diagnosed pulmonary TB at two main TB centers in Myanmar during 2013 by using conventional phenotypic DST and the GenoType MTBDRplus assay (Hain Lifescience, Germany). Discrepant results were confirmed by sequencing the genes relevant to each type of resistance (rpoB for rifampicin; katG and inhA for isoniazid). RESULTS: Of 191 isolates, phenotypic DST showed that 27.7% (n=53) were resistant to at least one first-line drug and 20.9% (n=40) were resistant to two or more, including 18.3% (n=35) multidrug-resistant TB (MDR-TB) strains. Monoresistant strains accounted for 6.8% (n=13) of the samples. Genotypic assay of 189 isolates showed 17.5% (n=33) MDR-TB and 5.3% (n=10) isoniazid-monoresistant strains. Genotypic susceptibility results were 99.5% (n=188) concordant and agreed almost perfectly with phenotypic DST (kappa=0.99; 95% confidence interval 0.96-1.01). CONCLUSIONS: The results highlight the burden of TB drug resistance and prove the usefulness of the genotypic DST in Myanmar.

Current trends of antibiotic sensitivity pattern of bacterial pathogens isolated from dysentery cases from clinics

A cross-sectional descriptive clinic based study was carried out among 150 dysentery cases attending the three general practitioners clinics from February 1998 to June 1999. The cases comprised 62 percent males and 38 percent females. The age range was from six months to 72 years. The siolated bacterial pathogens were Enteropathogenic Escherichia coli (EPEC) (8 percent);Enterotoxigenic Escherichia coli (ETEC) (6.7 percent); Shigella species (6.7 percent),out of which were Shigella flexneri (50 percent), Shigella dysenteriae (40 percent)and Shigella sonnei (10 percent). The antibiotic susceptibility revealed that EPEC were sensitive to amikacin, augmentin, furazolidone, gentamicin, netilmicin, norfloxacin, nalidixic acid (83.3 percent) each, sisomycin and chloramphenicol (75 percent)each, cephalothin, streptomycin and neomycin (66.7 percent) each, and septrin (58.3 percent). They were resistant to ampicillin (66.7 percent), tetracycline (75 percent), and carbenicillin (66.7 percent). Shigella species were sensitive to netilmicin (100 percent), norfloxacin (100 percent), amikacin, augmentin, furazoli-done, gentamicin (80 percent) each, cephalothin, nalidixic acid, neomycin, septrin (70 percent)each. They were sesistant to streptomycin (100 percent),chloramphenicol (80 percent), tetracycline (80 percent), carbenicillin (70 percent)and ampicillin (60 percent).

Current trends of antibiotic susceptibility pattern of bacterial pathogens isolated from dysentery cases from clinics

A cross-sectional descriptive clinic based study was carried out among 150 dysentery case attending the three general practioners' clinic from February 1998 to June 1999.The cases comprised 62 patients males and 38 percent females.The age range was from six month to 72 years.The isolated bacterial pathogens were Enteropathogenic Escherichia Coli (EPEC) (8 percent); Enterotoxigenic Escherichia coli (ETEC) (6.7 percent); shigella species (6.7 percent), out of which were Shigella Flexneri (50 percent), shigella dysenteiae (40 percent) and shigella sonnei(10 percent).The antibiotics susceptibility revealed that EPEC were sensitive to amikacin, augmentin, furazolidone, gentamicin, netilmicin, norfloxacin, nalidixic acid (83.3 per cent ) each; sisomycin and chloramphenicol (75 per cent ) each, cephalothin, streptomycin and neomycin (66.7 percent) each, septrin (58.3 percent).They were resistant to ampicillin (66.7 percent), tetracycline (75 percent) and carbinicillin (66.7 percent).Shigella species were sensitive to netilmicin (100 percent), norfloxacin (100 percent), amikacin, augamentin, furazolidone, gentamicin (80 percent) each, cephalothin, nalidixic acid, neomycin, septrin (70 percent) each.They were resistant to streptomycin (100 percent), chloramphenicol (80 percent), tetracycline (80 percent), carbenicillin (70 percent) and ampicillin (60 percent).