Biopsy is an important tool used to diagnose extra-pulmonary TB. It is the removal and examination of tissues from the living body to determine the existence or cause of a disease. It involves the microscopic examination of a small specimen of tissue extracted from the patient’s body. It is particularly useful for diagnosing extra-pulmonary TB in the lymph nodes and joints, as well as other affected organs. It can also be used to confirm pulmonary TB by sampling lung tissue in smear-negative suspects. Again, only doctors and clinicians are allowed to request this type of examination to diagnose TB.