title: Nocardia isolation from clinical samples with the paraffin baiting technique.
abstract: BACKGROUND
  The genus Nocardia is a cause of infection in the lungs, skin, brain, cerebrospinal fluid, eyes, joints and kidneys. Nocardia isolation from polymicrobial specimens is difficult due to its slow growth. Several methods have been reported for Nocardia isolation from clinical samples. In the current study, we used three methods: paraffin baiting technique, paraffin agar, and conventional media for Nocardia isolation from various clinical specimens from Iranian patients.
  
  
  METHODS
  In this study, we examined 517 samples from various clinical specimens such as: sputum of patients with suspected tuberculosis, bronchoalveolar lavage, sputum of patients with cystic fibrosis, tracheal aspirate, cutaneous and subcutaneous abscesses, cerebrospinal fluid, dental abscess, mycetoma, wound, bone marrow biopsy, and gastric lavage. All collected specimens were cultured on carbon-free broth tubes (paraffin baiting technique), paraffin agar, Sabouraud dextrose agar, and Sabouraud dextrose agar with cycloheximide and were incubated at 35°C for one month.
  
  
  RESULTS
  Seven Nocardia spp. were isolated with paraffin baiting technique, compared with 5 positive results with the paraffin agar technique and 3 positive results with Sabouraud dextrose agar with and without cycloheximide. The prevalence of nocardial infections in our specimens was 5.28%.
  
  
  CONCLUSIONS
  In the present study, the use of the paraffin baiting technique appeared to be more effective than other methods for Nocardia isolation from various clinical specimens.
authors.affiliation: PhD, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi Fatahi
authors.initials: MF
authors.lastname: Bafghi
authors.affiliation: PhD, Department of Bacteriology and Virology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran.
authors.forename: Parvin
authors.initials: P
authors.lastname: Heidarieh
authors.affiliation: MD, Department of Infectious Diseases, Razi hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Tahereh
authors.initials: T
authors.lastname: Soori
authors.affiliation: MD, Department of Pulmonary Infection, Doctor Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Sasan
authors.initials: S
authors.lastname: Saber
authors.affiliation: PhD, Department of Community Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Alipasha
authors.initials: A
authors.lastname: Meysamie
authors.affiliation: BSc, Department of Pulmonary Infection, Doctor Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Khavar
authors.initials: K
authors.lastname: Gheitoli
authors.affiliation: PhD student, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shadi
authors.initials: S
authors.lastname: Habibnia
authors.affiliation: PhD student, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Rasouli Nasab
authors.affiliation: PhD, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Seyyed Saeed
authors.initials: SS
authors.lastname: Eshraghi
keywords: Nocardia; Sabouraud dextrose agar; paraffin agar; paraffin baiting technique