Hemostatic and adhesive agents date back to World War II, when homologous fibrin sealant came onto scene. Considering that infectious diseases can be transmitted via human blood, a new heterologous fibrin sealant was standardized in the 1990s. Its components were a serine protease (a thrombin-like enzyme) extracted from the venom of Crotalus durissus terrificus snakes and a fibrinogen-rich cryoprecipitate extracted from the blood of Bubalus bubalis buffaloes. This new bioproduct has been used as a coagulant, sealant, adhesive and recently as a candidate scaffold for mesenchymal stem cells and bone and cartilage repair. This review discusses the composition of a new heterologous fibrin sealant, and cites published articles related to its preclinical applications aiming at repairing nervous system traumas and regenerating bone marrow. Finally, we present an innovative safety trial I/II that found the product to be a safe and clinically promising candidate for treating chronic venous ulcers. A multicenter clinical trial, phase II/III, with a larger number of participants will be performed to prove the efficacy of an innovative biopharmaceutical product derived from animal venom.Electronic supplementary materialThe online version of this article (doi:10.1186/s40409-017-0109-8) contains supplementary material, which is available to authorized users.

BackgroundHeterologous fibrin sealant (HFS) consists of a fibrinogen-rich cryoprecipitate extracted from Bubalus bubalis buffalo blood and a thrombin-like enzyme purified from Crotalus durissus terrificus snake venom. This study evaluated the safety and immunogenicity of HFS, estimated the best dose, and assessed its preliminary efficacy in the treatment of chronic venous ulcers (CVU).MethodsA phase I/II non-randomized, single-arm clinical trial was performed on 31 participants, accounting for a total of 69 active CVUs. All ulcers were treated with HFS, essential fatty acid, and Unna boot for 12 weeks. The outcomes assessed were: (1) primary safety, immunogenicity analyses, and confirmation of the lowest safe dose; (2) secondary promising efficacy by analyzing the healing process. Immunogenicity was evaluated using the serum-neutralizing (IgM and IgG) and non-neutralizing (IgA and IgE) antibody techniques against the product. The immuno-detection of IgE class antibodies was assessed using dot-blot assay before and at the end of treatment. Positive samples on dot-blot assays were subsequently analyzed by western blotting to verify the results.ResultsNo severe systemic adverse events related to the use of HFS were observed. Local adverse events potentially related to treatment include ulcer pain (52%), peri-ulcer maceration (16%), peri-ulcer pruritus (12%), critical colonization (8%), peri-ulcer eczema (4%), the opening of new ulcers (4%), and increased ulcerated area 4%). Neutralizing and non-neutralizing antibodies did not show significant deviations at any of the evaluated time points. Blot assays showed that all patients presented negative immunological reactions, either before or after treatment, with the thrombin-like enzyme component. In addition, two participants showed a positive immunological reaction to the cryoprecipitate component, while another two were positive before and during treatment. Regarding the secondary outcomes of preliminary efficacy, a total healing and significant reduction of the area was observed in 47.5 and 22%, respectively. A qualitative improvement was observed in the wound beds of unhealed ulcers.ConclusionsThe investigational HFS bioproduct proved to be safe and non-immunogenic with a good preliminary efficacy for the treatment of CVU, according to the protocol and doses proposed. A multicentric phase III clinical trial will be necessary to verify these findings.

CONTEXT AND OBJECTIVE: Chronic urticaria-angioedema is a common, multiple-cause complaint. The aim was to investigate the sociodemographic and clinical characteristics, causal and aggravating factors and evolution of urticaria-angioedema. DESIGN AND SETTING: This was a descriptive prospective study carried out at the Dermatology outpatient clinic of Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (Unesp). METHODS: A total of 125 patients with chronic urticaria-angioedema were evaluated to obtain sociodemographic data, anamnesis, dermatological and general clinical data and laboratory data, emphasizing causal and aggravating factors and complaint evolution. RESULTS: Chronic urticaria-angioedema occurred mainly in females (mean age: 35 years), but also in men (mean age: 32 years). White color and living in urban areas also predominated. There was no preferential time for symptoms to appear, and nighttime was the most commonly reported time for clinical worsening. Around half of the patients had urticaria associated with angioedema. There were no associated factors in most of the cases, and stress was the most commonly reported aggravating factor. The cause was ascertained in 37.6% of our cases. The mean duration of follow-up was 11.7 months. Around 60% of the patients evolved with the problem under control, 32% improved, 9% had no change in dermatological condition and only one patient worsened. CONCLUSIONS: Chronic urticaria-angioedema was more common among middle-aged women. It is a long-term disease, and its cause was explained in about one-third of the patients. Half of the patients presented disease control after treatment lasting an average of approximately one year.

CONTEXT AND OBJECTIVE: An association between chronic idiopathic urticaria (CIU) and autoimmune thyroid disease (ATD) has been reported. However, there have not been any reports on whether ATD raises the risk of angioedema, which is a more severe clinical presentation of CIU. Thus, the aim of the present study was to evaluate whether the risk of angioedema is increased in patients with CIU and ATD. DESIGN AND SETTING: Case-control study including 115 patients with CIU at a tertiary public institution. METHODS:The patients were evaluated with regard to occurrence of angioedema and presence of ATD, hypothyroidism or hyperthyroidism. RESULTS: Angioedema was detected in 70 patients (60.9%).

Resumo: FUNDAMENTOS -Drogas podem desencadear reações adversas. As manifestações cutâneas são as mais comuns. OBJETIVO -Analisar as farmacodermias e relacionar as drogas envolvidas e os tipos de reações cutâneas mais freqüentes.