Late diagnosis and TCD8 immune response profile of cutaneous tuberculosis: A case report

Introduction: Cutaneous tuberculosis (CTB) is a rare form of extra-pulmonary tuberculosis that, when associated with late diagnosis, worsen the quality of life of the sick individuals. This report presents a case of late diagnosis of CTB. Unusual clinical manifestations retarded the correct tuberculosis diagnosis for more than a year. The immune response elicited by this type of tuberculosis as well as the factors that might contribute to the delay in diagnosis was evaluated and discussed. Methodology: Clinical evaluation and flow cytometric analyses of PBMC were realized for a case of CTB and a healthy individual as a control. Results: M. tuberculosis specific TCD8+ cell response was analyzed by flow cytometry and revealed positive cells for IL-17, IL-10, TGF-β and IDO. The CTB patient presented higher percentage of those cells when compared to a healthy donor. However, TCD8 cells positive for the important protective cytokine, IFN-γ was decreased in the CTB patient. Conclusion. The assessment of the M. tuberculosis specific TCD8+ immune response showed a regulatory/modulatory phenotype with a reduced IFN-γ response when compared to the healthy control that could have contributed to the CTB infection.