Avaliação dos aspectos locais e imunológicos decorrentes de acidente botrópico no Amazonas

Abstract

Bothrops atrox snake is responsible for most reports of snakebites in the North region of Brazil. The inflammatory reaction triggered by the venom is responsible for serious local and systemic effects observed in patients. However, given a limitation of the local action of the serum on the patient, the local effects of the venom are more difficult to treat. Considering the importance of the inflammatory response associated with the clinical effects observed in the envenomation, the present project aimed to evaluate clinical, laboratory and immunological aspects of the local effects resulting from bothropic envenomation in Amazonas. This is an observational case series study, longitudinal and retrospective carried out in patients who were victims of bothropic accidents attended at the Fundação de Medicina Tropical Doutor Heitor Vieira Dourado (FMT-HVD), between 2014 and 2016. At patient admission (T0), 24h (T1), 48h (T2), 72h (T3) and 7 days after serum therapy (T4) were the moments when blood samples were collected and clinical parameters (local edema, local temperature and pain) and laboratory parameters were evaluated. From the plasma obtained from the patients' blood, cytokines and chemokines were evaluated, in addition to laboratory parameters such as total leukocytes, neutrophils and erythrocyte sedimentation rate (ESR), creatine kinase (CK) and lactate dehydrogenase (LDH). A total of 94 patients were considered eligible for the study, 42 with secondary infection and 52 without secondary infection. Regarding the clinical parameters, an edema and a local temperature rise were observed, which remained raised over time, but without changes between these times. As for pain, patients had a higher frequency of moderate and severe pain at T0, decreasing over time. In the correlation analysis between cytokines/chemokines, laboratory parameters and clinical parameters a positive correlation was observed between edema and local temperature with IL-6 and TNF, total leukocytes, neutrophils and ESR. This same analysis was able to show a response profile involving soluble mediators and cellular and tissue injury parameters. No correlations were observed between pain and inflammatory and laboratory mediators. The analyzes between patients with and without secondary infection showed that the bacterial infection event was responsible for potentialize the inflammatory response related to the action of the venom, with the mediators IL-6, IL-10, CXCL-8, total leukocytes, neutrophils and ESR being increased when the infection is installed. Furthermore, the mediators IL-10, CCL-2, CXCL-8 and CXCL-10 were elevated prior to the day of diagnosis of secondary infection, crediting such cytokines/chemokines as potential predictors of infection. On the other hand, ESR values are increased from the confirmation of secondary infection, which may be a marker that helps in the diagnostic confirmation of this infection. The results obtained in the present study were able to elucidate pathophysiological aspects of the local effects associated with the inflammatory process, associating clinical and laboratory parameters. The study also showed for the first time the real importance of secondary infection in inflammatory aspects, enhancing the immune response induced by the venom.