Dear Sir, your child is of two years age, and in this age group, one has to be sure of TB, before giving drugs, simply because, the treatment continues for a period of almost 1 year in bone TB, Second thing is regarding confirmation, you have gone for a biopsy, but you fail to mention what are her ESR and CRP levels, as they have a great significance if we think of TB, moreover, the culture for AFB does not need pus, any tissue can be given, but i suspect now that we would be having any tissue left. There is one another investigation that can be done from blood which can be done its called TB gold. Based on all these we have to start drugs, Moreover I would like to mention here, since TB is endemic in our country, many physicians start it on trial basis,this was quite acceptable in the past when we had no sophesticated methods of diagnosis, but now a days this is not practiced any more

In tuberculosis of bone..many a times there is no pus for culture..so even if stain is done it shows negative as the bacteria may be present in another field.. The tests which are done in case of tuberculosis of bone are mri which has already been done..along with that mantoux test and complete blood count. A sample can also be sent for PCR of TB which is polymerase chain reaction where a segment of the infected bone is taken and amplified in a dish to check. If it shows mycobacteria then she needs to be started on medications.. It is not necessary to specifically see a mycobacteria tuberculosis as there are 100 sub species of atypical mycobacteria.. Hope she gets well soon..