Table of Contents
ISRN Pulmonology
Volume 2013, Article ID 256148, 8 pages
Clinical Study

Blood Cells and Interferon-Gamma Levels Correlation in Latent Tuberculosis Infection

1Advanced Laboratory of Public Health, Oswaldo Cruz Foundation, Gonçalo Moniz Research Center, 40296 710 Salvador, BA, Brazil
2Bahia School of Medicine and Public Health, 40290 000 Salvador, BA, Brazil
3Hospital Especializado Octávio Mangabeira, Secretariat of Health of Bahia State, 40320 350 Salvador, BA, Brazil
4Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, CA 94720, USA

Received 20 November 2012; Accepted 12 December 2012

Academic Editors: A. Altraja and N. P. Juffermans

Copyright © 2013 Iukary Takenami et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The Mycobacterium tuberculosis (M. tb) infection is largely spread in world's population. Most infected individuals develop latent tuberculosis infection (LTBI). Tuberculin skin test (TST) and interferon-gamma release assays (IGRAs) are the available tests to detect the infection. It has been reported that some individuals take a longer period of time to develop the infection than others with the same exposure level. It is suggested that the innate immunity, in which neutrophils have an important protective role, is responsible for this. Many hematologic abnormalities have been described as common findings during severe disease. To investigate if these changes are related to LTBI development and if they interfere in TST and IFN-γ production, we recruited 88 household contacts of tuberculosis (TB) pulmonary patients and compared blood cell counts with these tests' results. There were no statistically significant changes in hemoglobin, hematocrit, platelets, global leukocyte, neutrophils, basophils, eosinophils, typical lymphocytes, atypical lymphocytes, and monocytes counts between infected and noninfected individuals. Also, there was no correlation between TST or IGRA and blood cell counts. These results suggest that blood cell counts are not LTBI markers and do not interfere in TST results or IFN-γ levels obtained by IGRA.