title: Urine PCR evaluation to diagnose pulmonary tuberculosis.
abstract: BACKGROUND
  Culture and specific staining (including Zeil-Nelson and fluorescent methods) are standard measures for the diagnosis of tuberculosis (TB). These methods are time-consuming and sometimes have a low level of accuracy. In addition, in some cases obtaining samples for smear and culture involves invasive procedures; while in other cases there is no suitable sample for evaluation. Therefore, there is a need for faster and more accurate diagnostic methods.
  
  
  OBJECTIVE
  The current study investigated the diagnostic value of tuberculosis-polymerase chain reaction (TB-PCR) of urine in the diagnosis of pulmonary tuberculosis (PTB).
  
  
  METHODS
  This case-control study included; 77 proven pulmonary tuberculosis cases (according to the national TB protocol), and 30 subjects who were completely healthy. The urine samples (50 mL) were mixed with 0.5 mL Ethylene diamine tetraacetic acid. DNA extraction and PCR testing were performed on all blood samples using SI 6110 primers. Mycobacterium tuberculosis was also cultivated in the sputum and urine samples of the patients.
  
  
  RESULTS
  Results of the current study indicated that 48 (62.3%) patients out of 77 had a positive sputum culture. Urine cultures and acid-fast smears were negative. Urine PCR-TB was positive in 48.0% (37/77) of the patients. The speciﬁc TBPCR complex was positive in 56.2% (27/48) of the positive cultures and 34.4% (10/29) of the negative culture PTB patients. The control group had negative urine PCR (sensitivity 56.2% and specificity 100%).
  
  
  CONCLUSIONS
  With regard to the ease of urine sample preparation and the 100% specificity the PCR method, performing urine PCR could be used as a diagnostic aid in PTB cases obtaining sputum samples is problematic.
authors.affiliation: Infectious Diseases Preventable by Vaccine Research Center, Mashhad, IR Iran.
authors.forename: Ali Akbar
authors.initials: AA
authors.lastname: Heydari
authors.affiliation: Infectious Diseases Department, Imam Reza Hospital, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors.forename: Masood Reza
authors.initials: MR
authors.lastname: Movahhede Danesh
authors.affiliation: Microbiology Department, Imam Reza Hospital, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors.forename: Kiarash
authors.initials: K
authors.lastname: Ghazvini
keywords: Mycobacterium tuberculosis; Polymerase Chain Reaction; Sensitivity and Specificity; Tuberculosis; Urine