Hi i am Dr Ahmed Aly thanks for using healthcaremagic site , I had gone through your question and understand your concerns .. In my opinion with your friends case its according to the stage of disease and his physical condition in most of cases it is ok for PTB patients to undergo knee arthroscopy but that decision is determined by the anaseathologist and your treating doctor . Tuberculosis is a condition which is caused by bacteria Mycobacterium tuberculosis and this condition affects lungs. Most common symptoms of tuberculosis include chronic or persistent cough and sputum production (if sputum contains blood this means that condition has advanced), fatigue, lack of appetite, weight loss, fever and night sweats. When it comes to the treatment option, you will be prescribed three or four different kinds of antibiotics and unfortunately you will have to take them for at least six months. And you must follow the instructions given by your doctor because if treatment doesn’t work you can find yourself in really big trouble as it also may affect the bones in late stages . Please click and consider a 5 star rating with some positive feedback if the information was helpful. Wish you good health, Any further clarifications feel free to ask.