title: Urine-Based Nested PCR for the Diagnosis ofMycobacterium tuberculosis: A Comparative Study Between HIV-Positive and HIV-Negative Patients.
abstract: BACKGROUND
  While tuberculosis (TB) can be diagnosed by microscopy and culture, the sensitivity of Ziehl-Neelsen staining is variable and culture results require 4 - 8 weeks to be determined. Polymerase chain reaction (PCR) and its modifications, including nested PCR, might be promising methods for the rapid diagnosis of TB.
  
  
  OBJECTIVE
  This study aimed to evaluate the performance of nested PCR on urine samples of human immunodeficiency virus (HIV)-positive and -negative patients with different manifestations of clinical TB.
  
  
  METHODS
  In a prospective study, three early-morning urine samples from 100 patients with pulmonary TB (PTB) or extrapulmonary TB (EPTB) were evaluated using a molecular target with insertion element IS6110, specific to theMycobacterium tuberculosisgenome, and nested PCR was performed. The results were analyzed with SPSS version 22.
  
  
  RESULTS
  A total of 100 patients, including 74 (74%) with PTB and 26 (26%) with EPTB, were enrolled. Positive smears were seen in 38 patients (38%). Lymph nodes were the most commonly involved organ in 14 of the 26 (53.8%) EPTB patients (13.5%). Seven (23.1%) of the EPTB patients were HIV-positive. Urine PCR was positive in only 28 patients (28%). Seven HIV-positive patients with PTB showed positive urine PCR results. Moreover, PCR results were positive in only one of the seven HIV-positive subjects with EPTB. Positive PCR results were found in 20 of the 73 HIV-negative patients (27.4%) and in 8 of the 27 HIV-positive patients (29.6%). Therefore, there was no significant difference between the HIV-negative and HIV-positive patients for urine PCR (sensitivity 29.6%, specificity 72.6%; positive and negative predictive values 28% and 72%, respectively; P = 0.138).
  
  
  CONCLUSIONS
  Nested PCR showed the same sensitivity in HIV-positive and HIV-negative patients. It can be applied as a rapid technique for the diagnosis of TB.
authors: Antimicrobial Resistance Research Center, Iran University of Medical Sciences, Tehran, IR Iran.
authors: Mahin
authors: M
authors: Jamshidi Makiani
authors: Infectious Disease Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, IR Iran.
authors: Parivash
authors: P
authors: Davoodian
authors: Cellular & Molecular Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, IR Iran.
authors: Mahnaz
authors: M
authors: Baghershiroodi
authors: Infectious Disease Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, IR Iran; Cellular & Molecular Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, IR Iran.
authors: Abdol Azim
authors: AA
authors: Nejatizadeh
authors: Bandar Abbas Health Center, TB control center, Hormozagan University of Medical Sciences, Bandar Abbas, IR Iran.
authors: Farideh
authors: F
authors: Fakkhar
authors: Department of Infectious Disease, Tehran Medical Branch, Islamic Azad University, Tehran, IR Iran; Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, IR Iran.
authors: Mehrangiz
authors: M
authors: Zangeneh
authors: Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, IR Iran.
authors: Nadia
authors: N
authors: Jahangiri
keywords: HIV Seropositivity; Mycobacterium tuberculosis; Polymerase Chain Reaction; Urine Specimen Collection