الفهرس | Only 14 pages are availabe for public view |
Abstract This thesis focused on evaluation of two low-cost phenotypic methods; the microscopic observation drug susceptibility (MODS) assay and the nitrate reductase (NRA) as alternatives for the rapid and accurate detection of TB and its susceptibility pattern to the first-line anti-tuberculosis drugs. All collected 62 smear positive sputum specimens were subjected to grading by ZN stain, mycobacterial cultures (on Lowenstein-Jensen (LJ) &radiometric BACTEC 460 TB system) and direct simultaneous culture &sensitivity test for the first line anti-TB drugs; streptomycine (STR), isoniazid (INH), rifampicin (RIF) and ethambutol (ETH) by microscopic observation drug susceptibility (MODS) assay. All LJ positive TB cultures (43) were subjected to indirect antimycobacterial susceptibility test (AST) for the same drugs by proportion method (PM) and indirect NRA. BACTEC 460 system was taken as a reference standard culture method while indirect PM on LJ was taken as a reference standard for AST. The agreement between MODS assay and LJ PM was good for (low &high conc. of INH, STR, low ETH conc.), moderate for high conc. Of ETH and excellent for low &high conc of RIF. There were an excellent agreement between indirect NRA and indirect LJ PM for INH, RIF &STR (kappa=0.85, 0.86 &0.81 respectively) and a moderate agreement for ETH (kappa=0.53). |