Avaliação epidemiológica e imunológica de alterações pulpo-periapicais em indivíduos com anemia falciforme

Abstract

Periapical diseases develop as a consequence of immune response against microorganisms and their byproducts. This response has not been previously analyzed in patients with sickle cell anaemia (SCA): the most prevalent genetic disease worldwide. This hemoglobinopathy results in the production of abnormal hemoglobin, called hemoglobin S (HbS). HbS leads to erythrocyte rigidity and vasoocclusion, resulting in progressive damage to systemic organs. The aims of this study were to evaluate the need of endodontic treatment and to do the immunologic analyse of the teeth with the need of endodontic treatment in patients with SCA. In this study, personal information, medical data (haematological indices, virologic testing, blood transfusions, medications received, splenectomy) and information on the need for endodontic treatment were obtained from SCA patients. Moreover, in the SCA patients that needed for endodontic treatment it was evaluated, using realtime PCR, the mRNA expression levels of the cytokines interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-17A, IL-10, receptor activator for nuclear factor kappa B ligand (RANKL), and the chemokines CCL-2/MCP-1 and CCL-5 in the periapical interstitial fluid and compared with results from non-SCA individuals. One hundred eight SCA patients comprised the studied population, and the rate of the need for endodontic therapy was 10.2%. Among the medical data, a significant difference was observed for eosinophil (p=0.045) counts and atypical lymphocyte counts (p=0.036) when the groups (with and without the need for endodontic treatment) were compared. These differences suggest that endodontic infections could be harmful to SCA individuals. Concerning to periapical immune response, no significant differences were observed in the expression of cytokine or chemokine mRNA between SCA and non-SCA individuals (p> 0.05). However, the expression of mRNA for the Th1-associated cytokines IFN-γ, TNF-α, and IL-1β were significantly higher in SCA individuals than in the control individuals (p< 0.05). Among Th1-associated cytokines, only IFN-γ was significantly increased in non-SCA compared with control patients (vital pulp). The expression of IL-17A mRNA was significant higher in SCA cases than in control samples (p< 0.05), while the IL-10 mRNA expression was significant increased in SCA and non-SCA individuals when compared with the control group. Similar levels of RANKL, CCL-2, and CCL-5 mRNA expression were observed in all samples. The results were unable to demonstrate any differences in periapical immune responses between SCA and non-SCA individuals despite the fact that SCA patients presented prone proinflammatory ability, expressing IL-1, TNF-α, and IL-17A at a significantly higher level compared to control patients than non-SCA individuals compared to control patients.