title: Real-Time Assay as A Tool for Detecting lytA Gene in Streptococcus pneumoniae Isolates.
abstract: OBJECTIVE
  In-time diagnosis of Streptococcus pneumoniae (S. pneumonia) can play a significant role in decreasing morbidity and mortality rate. Applying molecular methods has gained popularity due to the existing limits of routine diagnostic methods. Examining the expression of different genes of this bacterium through different molecular methods suggests that lytA gene has a higher sensitivity and specificity in diagnosis of Streptococcus pneumoniae. The aim of this study was to evalutate lytA gene expression in diagnosis of invasive S. pneumonia in culture positive specimens by real-time polymerase chain reaction (PCR).
  
  
  METHODS
  IIn this a descriptive study, All received specimens were isolated to identify S. pneumoniae. DNA was then extracted and after optimizing the test and determining the detection limit, samples were tested by real-time PCR using lytA gene primers.
  
  
  RESULTS
  Twenty seven isolates were diagnosed as S. pneumoniae. In all, the extracted DNA was positive in real-time method. The electrophoresis of the products also confirmed the presence of single product b along with the 53 base pair fragment. The detection limit of the test was less 6 colony forming unit (CFU).
  
  
  CONCLUSIONS
  Real-Time PCR seems to provide reliable and rapid results. We suggest that this test should be conducted on the preliminary isolated specimens, since applying various biochemical tests need one extra working day.
authors.affiliation: Reference Health Laboratories Research Center, Ministry of Health & Medical Education, Tehran, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Hajia
authors.affiliation: Science and Research Branch, Islamic Azad University, Arak, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Farzanehkhah
authors.affiliation: Science and Research Branch, Islamic Azad University, Arak, Iran.
authors.forename: Bahareh
authors.initials: B
authors.lastname: Hajihashemi
authors.affiliation: Reference Health Laboratories Research Center, Ministry of Health & Medical Education, Tehran, Iran.
authors.forename: AliReza
authors.initials: A
authors.lastname: Dolatyar
authors.affiliation: Reference Health Laboratories Research Center, Ministry of Health & Medical Education, Tehran, Iran.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Imani
authors.affiliation: Reference Health Laboratories Research Center, Ministry of Health & Medical Education, Tehran, Iran.
authors.forename: Roghieh
authors.initials: R
authors.lastname: Saburian
authors.affiliation: Reference Health Laboratories Research Center, Ministry of Health & Medical Education, Tehran, Iran.
authors.forename: Marjan
authors.initials: M
authors.lastname: Rahnamaye Farzami
authors.affiliation: Reference Health Laboratories Research Center, Ministry of Health & Medical Education, Tehran, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Rahbar
keywords: Real Time PCR; Streptococcus pneumoniae; lytA Gene