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- Antibodies Towards High-Density Lipoprotein Components in Patients with PsoriasisPublication . Paiva-Lopes, MJ; Batuca, J; Gouveia, S; Alves, M; Papoila, AL; Delgado Alves, JPsoriasis is a chronic inflammatory immune disorder associated with an increased risk of atherosclerosis. This increased risk is not fully understood. High-density lipoproteins (HDL) play an important role in the prevention of atherosclerosis and any factors that may hamper HDL function such as anti-HDL antibodies (aHDL) might be associated with an increased cardiovascular risk. We aimed to determine whether anti-HDL antibodies (aHDL) are present in patients with psoriasis. Sixty-seven patients with psoriasis were compared with a healthy control group. Epidemiologic and clinical data were recorded. IgG and IgM aHDL, IgG anti-apolipoprotein A-I (aApoA-I), anti-apolipoprotein E (aApoE), and anti-paraoxonase 1 (aPON1) antibodies, as well as VCAM-1, IL-6, and TNF-α were assessed by ELISA. Apolipoprotein A-I (ApoA-I) and Apolipoprotein E (ApoE) were measured by immunoturbidimetric immunoassay. Patients with psoriasis had higher titers of IgG aHDL (p < 0.001), IgG aApoA-I (p = 0.001) and aApoE antibodies (p < 0.001). IgG aHDL and aApoE titers were higher in patients with severe psoriasis (p = 0.010 and p = 0.018, respectively). Multiple regression analysis, considering all clinical and biological variables, showed that aApoE, IL-6, and aPON1 are the biological variables that best explain aHDL variability. This is the first report showing the presence of aHDL, aApoA-I, and aApoE antibodies in patients with psoriasis. These antibodies were associated with increased disease severity and may contribute to the pathogenesis of atherosclerosis in psoriasis. They may fulfill the clinical need for biomarkers of cardiovascular risk associated with psoriasis that would help to stratify patients for prevention and therapeutic approaches.
- Proposal of a New Standardized Freeze-Thawing Technical Protocol for Leucocyte-Poor Platelet-Rich Plasma Preparation and CryopreservationPublication . Caiado, A; Ferreira-Dos-Santos, G; Gonçalves, S; Horta, L; Soares Branco, PA human platelet-rich plasma (PRP) concentrate can be defined as a preparation of autologous human plasma with increased platelet concentration produced by centrifugation of a larger volume of a patient's own blood. Platelets contain a plethora of growth factors in their α-granules that are concentrated through the centrifugation process in order to then be injected in supraphysiologic amounts to an injury site with the final aim of augmenting the natural healing process. Preparations of PRP concentrates can be further classified as leucocyte-rich (LR-PRP), defined as having a leucocyte concentration above baseline, and leucocyte-poor (LP-PRP), defined as having a leucocyte concentration below baseline. Although many preclinical and clinical trials have shown the ability of leucocyte-poor PRP concentrates to significantly improve symptomatic mild to moderate hip and/or knee osteoarthritis, to date there is no consensus on the optimal way of obtaining PRP preparations, specifically with respect to the concentration of blood components. In this technical report, we describe a new standardized freeze-thawing technique for leucocyte-poor PRP preparation and cryopreservation, which has been shown to be superior to currently available techniques based solely on centrifugation. By describing this technical protocol, which we have been using on a daily basis in the setting of a Regenerative Medicine Outpatient Clinic in a European tertiary university hospital center, we aim to contribute to a future consensus on the optimal way of obtaining and preserving leucocyte-poor PRP concentrates.
- Primary Anti-Phospholipid Antibody Syndrome: Real-World Defining Features of Rethrombosis in the Course of DiseasePublication . Moraes-Fontes, MF; Pedro, F; Campos, MM; Fernandes, M; Yavuz, S; Oliveira, F; Panarra, AObjective: We aimed to identify features that allow differentiation of primary antiphospholipid syndrome (PAPS) patients that suffer recurrent thrombotic events (RTE) despite anticoagulation, from the other diagnosed PAPS patients. Methods: This was an exploratory study of anticoagulated PAPS patients attending an Autoimmune Diseases Unit (1998-2018). From 2016, anti-phospholipid antibodies and lupus anticoagulant were determined for each patient at consecutive visits, collected together with retrospective clinical characteristics, laboratory, and therapeutic markers and compared according to the occurrence of thrombotic events during follow-up. Results: Overall, two thirds of the patients were female, 93% were Caucasian, with a median age of 40 years at diagnosis, for a median time of 11.5 years in follow-up. Out of 54 patients, 10 were identified with RTE. There were no significant differences among the RTE and non-RTE patients as far as classical risk factors for clotting disorders. The RTE group was characterized by a higher proportion of younger patients, male sex and positivity for all laboratory markers, and initially and over follow-up as well as a sustained high-risk profile based on APS laboratory markers. Anticardiolipin IgG at onset was the only statistically significant marker of the RTE group. At the end of follow-up, consistent reversion to negative status was a rare event, observed in 20% of RTE vs. 25% of non-RTE patients. Conclusions: Despite therapy, we were able to identify features associated to thrombotic events in patients with PAPS. Prospectively regular clinical and laboratory monitoring might be warranted in order to treat APS more assertively.
- Disfunção Plaquetária Induzida pelo Darunavir em Doente com Infeção VIH-1Publication . Araújo, E; Pardal, R; Campos, MM; Marques, MJ; Silva, AC; Jacinto, M; Fernandes, AIAs plaquetas desempenham um papel importante na hemóstase primária e a sua disfunção pode resultar em manifestações hemorrágicas, principalmente, mucocutâneas. Apesar das manifestações serem, na maioria das vezes, de gravidade ligeira a moderada, os doentes com disfunção plaquetária podem constituir um desafio hemostático, quando submetidos a procedimentos invasivos. As causas podem ser hereditárias ou adquiridas. Diversos fármacos estão associados a disfunção plaquetária adquirida. Nesta revisão abordamos as alterações da agregação plaquetária associadas aos fármacos antirretrovíricos mais comumente utilizados na terapêutica do vírus da imunodeficiência humana. É destacada a associação dos inibidores da protéase com o aumento da incidência de eventos hemorrágicos, sobretudo nos doentes com coagulopatias congénitas. Apresentamos um caso clínico demonstrando a importância do estudo da função plaquetária pelo método de agregometria por transmissão de luz nos doentes infetados com o vírus da imunodeficiência humana e diátese hemorrágica, de forma a ser possível uma boa orientação clínica.
- INR vs Doseamento de Fator X Cromogénico e Fator II: C em Doentes com Síndrome Antifosfolipídica sob Anticoagulação Oral ClássicaPublication . Campos, MM; Lopes, JM; Marques, MJ; Rincón, F; Fernandes, AI; Ribeiro, ME; Silva, ACOs fatores dependentes da vitamina K podem estar diminuídos de modo variável, sendo o Fator (F) II e o FX os principais determinantes relativamente ao efeito antitrombótico. A ligação dos anticorpos antifosfolipídicos aos fosfolípidos pode causar um falso prolongamento do tempo de protrombina (TP) em doentes com anticoagulante lúpico. Correlacionámos os resultados da razão normalizada internacional (INR) – usando uma tromboplastina recombinante – com os níveis de FX (teste cromogénico) e de FII (teste coagulométrico baseado no TP). Os doseamentos de FX e FII correlacionaram-se bem entre si. Verificámos que INR e FII se correlacionaram melhor que INR e FX. A correlação da atividade do TP relativamente ao FX e ao FII foi superior à do INR com ambos os fatores da coagulação, sedo superior a correlação da atividade do TP com o FII. A tromboplastina utilizada para determinação do INR tem uma concentração elevada de fosfolípidos o que permite neutralizar o efeito de anticorpos. Consideramos o INR tão fiável como os outros testes submetidos a avaliação. O valor de INR é de rápida obtenção e baixo custo, enquanto o doseamento de fatores da coagulação é mais dispendioso e geralmente realizado em série para racionalização de recursos. Contudo, um doseamento de FX cromogénico, obtido 3 a 4 vezes no ano, pode ser útil como ferramenta adicional à monitorização de rotina através do INR.
- Recurrent Gastrointestinal Bleeding from Dieulafoy's Lesions in a Patient with Type 1 von Willebrand Disease: A Rare AssociationPublication . Ferreira Cardoso, M; Carvalho Lourenço, L; Antunes, M; Carvalho e Branco, J; Santos, L; Martins, A; Reis, JVon Willebrand disease (vWD) is the most prevalent hereditary bleeding disorder, affecting 0.6-1.3% of the population. While gastrointestinal bleeding from angiodysplasia is a well-known complication of vWD, the same is not true for Dieulafoy's lesions (DLs). We report the case of a 21-year-old black male with type 1 vWD and 2 previous hospital admissions for severe anemia with no visible blood loss. In both episodes, DLs were identified and treated endoscopically, one in the stomach and another in the duodenum. The patient presented to the emergency department in September 2016 with dizziness, fatigue, and again no visible blood loss. He was hemodynamically stable, and laboratory workup showed a hemoglobin level of 3.4 g/dL. After transfusion of packed red blood cells, intravenous iron, and von Willebrand factor/factor VIII concentrate infusions, the patient underwent upper endoscopy and colonoscopy, which were normal. Small-bowel capsule endoscopy showed dark blood and a fresh clot in the proximal jejunum. At this site, push enteroscopy identified a pulsatile vessel with an overlying minimal mucosal defect, consistent with a DL, type 2b of the Yano-Yamamoto classification, which was successfully treated with adrenaline and 2 hemoclips. The patient remains stable after 18 months of follow-up, with a hemoglobin level of 13.2 g/dL. This is a case of recurrent severe occult gastrointestinal bleeding from multiple DL in a young patient with vWD who is otherwise healthy. Three other cases of DL bleeding in the setting of vWD have been reported in the literature, suggesting a possible association between these 2 entities.
- Diagnóstico Laboratorial da Doença de Von Willebrand e da Síndrome de Von Willebrand Adquirida. Guia de BolsoPublication . Campos, MMProcedeu-se a uma breve revisão da doença de von Willebrand e da síndrome de von Willebrand adquirida, incluindo a classificação e estudos laboratoriais determinantes para o diagnóstico, que foram inseridos num algoritmo. A suspeição clínica fundada em manifestações hemorrágicas (história pessoal e familiar) é o pilar da investigação, contribuindo o laboratório para despiste, confirmação, caracterização em termos de diagnóstico e monitorização terapêutica. As abordagens sobre profilaxia e tratamento não estão contidas neste guia, focado em etapas de estratégia diagnóstica no âmbito do laboratório clínico e na solicitação de outros estudos para laboratórios de referência. As recomendações emanadas pelas sociedades científicas são fundamentais na avaliação de manifestações hemorrágicas, despiste analítico criterioso e em situações especiais.
- Abordagem da Hemostase e Anticoagulação no Contexto da Infeção Por SARS-CoV-2Publication . Sevivas, TS; Caiado, A; Rodrigues, A; Robalo Nunes, A
- Fatores Clínico-Biológicos e Variáveis Pré-Analíticas em Hemostase - o Expectável e o ImprevistoPublication . Campos, MMNesta revisão foca-se o impacto das variáveis pré-analíticas e de fatores epidemiológicos, fisiopatológicos, comportamentais e outros no processo laboratorial em hemostase, considerando a interação de mecanismos endógenos e comorbilidades com o ambiente e iatrogenia. Os erros mais frequentes no laboratório ocorrem na fase pré-analítica. Investigação bem planeada tem sido desenvolvida acerca de causas interferentes nas amostras, biomarcadores hemorreológicos e microcirculatórios e frequência de eventos hemorrágicos e trombóticos associados. Fatores como nutrição, idade, género, grupo sanguíneo, atividade física, gravidez, doenças crónicas, mutações, medicação anticoagulante e antiagregante plaquetária, procedimentos envolvendo circuitos extracorporais, hábitos, ritmo circadiano e fase aguda de eventos trombóticos, bem como condições das amostras interferem nos resultados. A heterogeneidade das variáveis independentes da metodologia laboratorial deve ser enfatizada, pois produz impacto na fiabilidade e valor diagnóstico, preditivo e de monitorização dos estudos da hemostase.
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