Why is isolation and identification of Mycobacterium tuberculosis so difficult? ?

Why is isolation and identification of Mycobacterium tuberculosis so difficult? ?


I looked for this in my micro book but I can't find anything about it. It just says that it is gram positive and tells about the PPD test. I also looked for this on the internet but can't really find what I need. Why is isolation and identification of Mycobacterium tuberculosis so difficult? ?
they are extremely hard to isolate and grow (fours weeks on an agar plate) which makes the use of diagnostic test almost impossible. here is a paper that may help.





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