PCR stands for Polymerase Chain Reaction, which is tested in urine during diagnosis of various diseases. The test comes handy in the diagnosis of pulmonary tuberculosis. Culture and specific staining, which include fluorescent and Zeil-Nelson methods, are standard measures that help in the diagnosis of tuberculosis or PTB (pulmonary tuberculosis). These are time-consuming methods and can also suffer from low-level of accuracy. Collection of samples for smear and culture also involves some invasive procedures. At times, more accurate diagnostic methods may also be required. Often, suitable samples for evaluation are not obtained which creates hassles for the treatment process.