Hello and welcome to Healthcare Magic. Thanks for your query. I understand that the persistent fever has been causing you a lot of distress and suffering. You seem to be having a Fever of Unknown Origin(FUO) . Any fever which is persistent for more than 3 weeks and remains undiagnosed despite having multiple hospital visits and 1 week of all the basic tests is classified as FUO. Extrapulmonary tuberculosis is the most frequent cause of FUO, which is why your doctor must be suspecting the same. Now extra-pulmonary tubeculosis does not involve the lungs and so does not have the typical symptoms of cough, sputu, weight loss, etc. and the regular tests done to detect TB (like sputum tests for TB) will all be negative. In such cases, a special test like Interferon TB Gold may be applied to detect the presence of TB infection. In some cases, when all possible tests have been done, and there is a suspicion of TB, empirical treatment for TB can be started even without an established diagnosis. I can understand that it can be very frustrating to have persistent symptoms without a diagnosis. But unfortunately, the evaluation of FUO needs a systematic approach, ruling out all possibilities one by one, starting from the most common to the least common. So, please be patient and liaise with your GP regarding further evaluation and treatment. Wish you all the best. Regards, Dr. Jonas Sundarakumar