Lower levels of CXCL-8 and IL-2 on admission as predictors of early adverse reactions to Bothrops antivenom in the Brazilian Amazon.

Snakebite envenomings are considered a global health problem. The specific therapy for these envenomings consists of administering animal-derived antivenoms aiming to neutralize the venom toxins. Antivenoms have been used effectively to treat snakebites for more than a century; however, their administration may result in early and/or late adverse reactions. The present study presents the prevalence of early adverse reactions (EARs) towards Bothrops antivenom therapy in a health tertiary unit in the Brazilian Amazon and explores if specific plasma cytokines and chemokines from envenomed patients could be used as predictors of EARs. A cohort of patients bitten by Bothrops atrox was followed-up at the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD), from 2014 to 2016. Patients were treated with the Brazilian Bothrops antivenom and CXCL-8, CCL-5, CXCL-9, CCL-2, CXCL-10, IL-6, TNF, IL-2, IL-10, IFN-y, IL-4, and IL-17A were evaluated in patients' plasma samples before and after antivenom administration. From the total of patients (n = 186), mostly were male (82.3%), inhabiting rural areas (87.1%), with an average age of 35 years. Most of the patients (83.8%) were admitted to the hospital within 6 h after the accident, 26 (14%) reported having suffered a previous snakebite, and 97 (52.1%) received between 7 and 9 antivenom vials. The frequency of antivenom-induced EARs was 11.8% (22), resulting mostly of mild reactions. Urticaria was the major EAR manifestation (46.4%). Interestingly, CXCL-8 and IL-2 showed significantly lower levels in patients who progressed to EARs, although IL-2 levels might not represent biological relevance due the small magnitude difference between groups. This study reveals that CXCL-8 and IL-2 could play a role in the onset of EARs in pit viper envenomings.

Lower levels of CXCL-8 and IL-2 on admission as predictors of early adverse reactions to Bothrops antivenom in the Brazilian Amazon

Snakebite envenomings are considered a global health problem. The specific therapy for these envenomings consists of administering animal-derived antivenoms aiming to neutralize the venom toxins. Antivenoms have been used effectively to treat snakebites for more than a century; however, their administration may result in early and/or late adverse reactions. The present study presents the prevalence of early adverse reactions (EARs) towards Bothrops antivenom therapy in a health tertiary unit in the Brazilian Amazon and explores if specific plasma cytokines and chemokines from envenomed patients could be used as predictors of EARs. A cohort of patients bitten by Bothrops atrox was followed-up at the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD), from 2014 to 2016. Patients were treated with the Brazilian Bothrops antivenom and CXCL-8, CCL-5, CXCL-9, CCL-2, CXCL-10, IL-6, TNF, IL-2, IL-10, IFN-y, IL-4, and IL-17A were evaluated in patients’ plasma samples before and after antivenom administration. From the total of patients (n = 186), mostly were male (82.3%), inhabiting rural areas (87.1%), with an average age of 35 years. Most of the patients (83.8%) were admitted to the hospital within 6 h after the accident, 26 (14%) reported having suffered a previous snakebite, and 97 (52.1%) received between 7 and 9 antivenom vials. The frequency of antivenom-induced EARs was 11.8% (22), resulting mostly of mild reactions. Urticaria was the major EAR manifestation (46.4%). Interestingly, CXCL-8 and IL-2 showed significantly lower levels in patients who progressed to EARs, although IL-2 levels might not represent biological relevance due the small magnitude difference between groups. This study reveals that CXCL-8 and IL-2 could play a role in the onset of EARs in pit viper envenomings.

Lessons Learned from Implementation of an Interferon Gamma Release Assay to Screen for Latent Tuberculosis Infection in a Large Multicenter Observational Cohort Study in Brazil.

The interferon gamma release assay (IGRA) has emerged as a useful tool for identifying latent tuberculosis infection (LTBI). This assay can be performed through testing platforms such as the QuantiFERON-TB Gold Plus (QFT-Plus) assay. This in vitro test has been incorporated into several guidelines worldwide and has recently been considered by the World Health Organization (WHO) for the diagnosis of LTBI. The possibility of systematically implementing IGRAs such as the QFT-Plus assay in centers that perform LTBI screening has been accelerated by the decreased availability of the tuberculin skin test (TST) in several countries. Nevertheless, the process to implement IGRA testing in routine clinical care has many gaps. The study utilized the expertise acquired by the laboratory teams of the Regional Prospective Observational Research in Tuberculosis (RePORT)-Brazil consortium during study protocol implementation of LTBI screening of tuberculosis (TB) close contacts. RePORT-Brazil includes clinical research sites from Brazilian cities and is the largest multicenter cohort of TB close contacts in the country to date. Operational and logistical challenges faced during IGRA implementation in all study laboratories are described, as well as the solutions that were developed and led to the successful establishment of IGRA testing in RePORT-Brazil. The descriptions of the problems identified and resolved in this study can assist laboratories implementing IGRAs, in addition to manufacturers of IGRAs providing effective technical support. This will facilitate the implementation of IGRA testing in countries with large TB burdens, such as Brazil. IMPORTANCE The IGRA has emerged as a useful tool for identifying persons with LTBI. Although the implementation of IGRAs is of utmost importance, to our knowledge there is scarce information on the identification of logistical and technical challenges for systematic screening for LTBI on a large scale. Thus, the descriptions of the problems identified and resolved in this study can assist laboratories implementing IGRAs, in addition to manufacturers of IGRAs providing effective technical support. This will facilitate the implementation of IGRA testing in countries with large TB burdens, such as Brazil.

Observation of Bothrops atrox Snake Envenoming Blister Formation from Five Patients: Pathophysiological Insights.

In the Brazilian Amazon, Bothrops atrox snakebites are frequent, and patients develop tissue damage with blisters sometimes observed in the proximity of the wound. Antivenoms do not seem to impact blister formation, raising questions regarding the mechanisms underlying blister formation. Here, we launched a clinical and laboratory-based study including five patients who followed and were treated by the standard clinical protocols. Blister fluids were collected for proteomic analyses and molecular assessment of the presence of venom and antivenom. Although this was a small patient sample, there appeared to be a correlation between the time of blister appearance (shorter) and the amount of venom present in the serum (higher). Of particular interest was the biochemical identification of both venom and antivenom in all blister fluids. From the proteomic analysis of the blister fluids, all were observed to be a rich source of damage-associated molecular patterns (DAMPs), immunomodulators, and matrix metalloproteinase-9 (MMP-9), suggesting that the mechanisms by which blisters are formed includes the toxins very early in envenomation and continue even after antivenom treatment, due to the pro-inflammatory molecules generated by the toxins in the first moments after envenomings, indicating the need for local treatments with anti-inflammatory drugs plus toxin inhibitors to prevent the severity of the wounds.

Observation of Bothrops atrox snake envenoming blister formation from five patients: pathophysiological insights

In the Brazilian Amazon, Bothrops atrox snakebites are frequent, and patients develop tissue damage with blisters sometimes observed in the proximity of the wound. Antivenoms do not seem to impact blister formation, raising questions regarding the mechanisms underlying blister formation. Here, we launched a clinical and laboratory-based study including five patients who followed and were treated by the standard clinical protocols. Blister fluids were collected for proteomic analyses and molecular assessment of the presence of venom and antivenom. Although this was a small patient sample, there appeared to be a correlation between the time of blister appearance (shorter) and the amount of venom present in the serum (higher). Of particular interest was the biochemical identification of both venom and antivenom in all blister fluids. From the proteomic analysis of the blister fluids, all were observed to be a rich source of damage-associated molecular patterns (DAMPs), immunomodulators, and matrix metalloproteinase-9 (MMP-9), suggesting that the mechanisms by which blisters are formed includes the toxins very early in envenomation and continue even after antivenom treatment, due to the pro-inflammatory molecules generated by the toxins in the first moments after envenomings, indicating the need for local treatments with anti-inflammatory drugs plus toxin inhibitors to prevent the severity of the wounds.