Comparative study between using Lowenstein Jensen and Bio-FM media in identification of Mycobacterium tuberculosis

Aim of the work: To evaluate the detection rate and time of Mycobacterium tuberculosis by using Bio-FM system in comparison with the Lowenstein Jensen medium. Patients and methods: A total of 50 smear AFB positive sputum samples were included in this study and received from three groups. Group I: Thirty four patients with fresh sputum smear +ve (new cases). Group II: Ten relapsed cases. Group III: Six treatment failure cases. All cases were exposed for thorough history taking, complete physical examination, routine laboratory tests including ESR, plain chest X-ray-PA and lateral view if needed, sputum smear for acid fast bacilli (Zeil Neelsen staining), tuberculin skin test using Mantoux technique, sputum culturing on Lowenstein Jensen medium and Bio-FM medium. Results: The shortest mean detection times on the two studied isolation media were for the cases with far advanced lesion on chest X-ray. On Lowenstein Jensen, it was 17.50 ± 6.802 days and on Bio-FM it was 10 ± 5.752 days. While the longest times were for the cases of minimal lesion, on Lowenstein Jensen, it was 24 days (±11.449) and on Bio-FM it was 15 days (±10.905). The mean detection times of moderately advanced cases on Lowenstein Jensen, it was 19.57 days (±9.086) and on Bio-FM was 12.65 days (±8.074). Conclusion: Bio-FM showed greater superiority in detection time over Lowenstein Jensen with no significant difference between the two media in detection rate