I presume that the diagnosis of TB has been made by the doctor based on the history and clinical presentation and corroborated by radiological and laboratory investigations.
Red discolouration of urine for this patient could be explained. She has been commenced on anti-TB drugs. Rifampicin is a key anti-TB drug, which is known to cause reddish/orange discolouration of urine and various body secretions, including tears.
Your wife needs to be reassured that it is not blood that is giving the colour to the urine.