Searching For Calmette - Guérin Bacilli in Bone Marrow Specimens of Vaccinated Children: A Real-Time PCR
Author(s): Ebrahim Sadeghi, Amir Nasimfar, Abdolvahab Alborzi, Mohamad Rahim Kadivar, Anahita Sanai dashti, Bahman Poorabas, Gholamreza Pooladfar
The Bacillus Calmette - Guérin (BCG) vaccine is purported to be disseminated in the body after inoculation via a lymphohematogenous route, even in immunocompetent individuals. This study was aimed to investigate the presence of Bacillus Calmette - Guérin in the bone marrow specimens of BCG vaccinated children using a molecular method. In this cross-sectional study, a total of 70 bone marrow samples were collected randomly from the hospitalized patients in Namazi and Amir Hospitals of Shiraz, Iran between April 2013 and March 2014. Bone marrow specimens were examined using the AmpliSens MD-FRT PCR kit (InterLabService Ltd, Moscow, Russia), designed for qualitative detection and differentiation of mycobacterium tuberculosis complex (M. tuberculosis, M.bovis, M.bovis BCG, etc.). Of the 70 cases, 42 (60%) were male. Patients’ age ranged from 8 months to 6 years, with the most frequent age group being the 2-3 years (22.8%). Bone marrow aspirate smears showed no histopathological sign of granuloma/caseous granuloma. The bone marrow aspirate smears were also negative for acid-fast bacilli staining (i.e. Ziehl-Neelsen stain). Samples were all found to be negative for BCG based on real-time PCR results. Our study showed no evidence of bone-marrow involvement of BCG in a group of sick vaccinated children with no clinical presentation of disseminated BCG disease.