Diagnóstico de la enfermedad de von Willebrand / Diagnosis of von Willebrand disease

La enfermedad de von Willebrand (EVW) es el trastorno hemorrágico hereditario más común, y se caracteriza por presentar disminución de la capacidad del factor von Willebrand (FVW) de unirse a las plaquetas y al colágeno de la matriz extracelular durante la hemostasia primaria, debido a defectos cuantitativos o cualitativos. La EVW se clasifica en tres fenotipos principales: el 1 y el 3 que son trastornos cuantitativos, y el 2 que se subclasifica en 2A, 2B, 2M y 2N, y refleja los trastornos cualitativos. Para su diagnóstico son necesarios varios pasos: 1) la evaluación del historial de sangrado personal y familiar del paciente, 2) detección inicial de trastornos hemorrágicos, 3) pruebas para la detección de la EVW, 4) pruebas para la tipificación de la EVW, y 5) el análisis molecular. Tanto la subclasificación de la EVW como su diagnóstico continúan planteando desafíos importantes, motivo por el cual se realiza esta revisión, de manera que los profesionales de la salud tengan una guía que los oriente al momento de tener pacientes con algún trastorno hemorrágico que amerite descartar una EVW e implementar un tratamiento adecuado

von Willebrand disease (VWD) is the most common hereditary bleeding disorder, and is characterized by a decreased ability of the von Willebrand factor (VWF) to bind to platelets and extracellular matrix collagen during primary hemostasis, due to quantitative or qualitative defects. VWD is classified into three main phenotypes: 1 and 3, which are quantitative disorders, and 2 (2A, 2B, 2M and 2N) that reflects qualitative disorders. Several steps are necessary for its diagnosis: 1) evaluation of the patient's personal and family bleeding history, 2) initial screening tests for bleeding disorders, 3) tests for the detection of VWD, 4) tests for the classification of VWD, and 5) molecular analysis. Both the subclassification of VWD and its diagnosis continue to represent important challenges, which we aimed to describe in this review, so that health professionals have a guide to assist them when they have patients with a bleeding disorder that requires exclusion of VWD, and implementation of an appropriate treatment.

Seguridad de la endoscopia y biopsia esofágica en un paciente con esofagitis eosinofílica y enfermedad de Von Willebrand / Safety of esophageal endoscopy and biopsy in a patient with eosinophilic esophagitis and Von Willebrand disease

La esofagitis eosinofílica (EoE) es una enfermedad causada por una respuesta inmune frente a antígenos alimentarios en contacto con la mucosa esofágica; por su parte, la enfermedad de Von Willebrand (EVW) es el trastorno hemorrágico hereditario más común en los seres humanos. La característica central de todos los tipos de EVW, es la presencia de cantidades reducidas o de formas anormales del factor de Von Willebrand (FVW) en el torrente sanguíneo. Debido a que no se han reportado casos previos de EVW tipo 2A asociada a EoE, se describe este caso clínico con el objetivo principal de dar a conocer el hallazgo casual de estas dos patologías, la seguridad de la evaluación por endoscopia de vías digestivas altas y el pronóstico de posibles complicaciones

Eosinophilic esophagitis (EoE) is a disease caused by an immune response against food antigens in contact with the esophageal mucosa; alternatively, Von Willebrand disease (VWD) is the most common inherited bleeding disorder in humans. The central characteristic of all types of VWD is the presence of reduced amounts or abnormal forms of VWF in the bloodstream. Since no previous cases of VWD type 2A associated to EoE have been reported, this clinical case is described with the main objective to present the coincidental finding of these two pathologies, the safety of the evaluation by upper gastrointestinal endoscopy, and the prognosis of possible complications

INFLUÊNCIA DOS DISTÚRBIOS HEREDITÁRIOS DE COAGULAÇÃO NO REPARO DE LESÕES PERIRRADICULARES / INFLUENCE OF HEREDITARY COAGULATION DISORDERS ON THE REPAIR OF PERIRRADICULAR INJURIES

Lesão perirradicular é uma doença de etiologia microbiana, cuja evolução possui forte relação com a resposta imunológica do hospedeiro, que ocorre no intuito de conter essa infecção. O tratamento endodôntico nesses casos tem como objetivo biológico final a desinfecção do sistema de canais radiculares para possibilitar o reparo da região periapical. Esse reparo é um processo complexo que consiste em hemostasia, inflamação, proliferação celular, maturação e remodelação. Diversos estudos vêm sendo realizados no intuito de relacionar fatores sistêmicos ou hábitos adquiridos com o desenvolvimento, diagnóstico, severidade e cura das lesões perirradiculares. Essas condições são referidas como modificadores da doença e podem esclarecer o surgimento de sintomatologia dolorosa em casos assintomáticos, a cura tardia de algumas lesões, e explicar o porquê alguns canais adequadamente tratados resultam em fracasso. As doenças hereditárias de coagulação causam alterações na hemostasia dos portadores, gerando propensão para sangramento abundante e modificações importantes na cicatrização de feridas. Essa revisão bibliográfica identificou as associações existentes entre os transtornos hereditários de coagulação mais comuns (hemofilias A e B e doença de von Willebrand) e o reparo de lesões endodônticas e concluiu que tal condição clínica pode afetar as respostas imunes, interferindo no reparo perirradicular.

Periradicular injury is a disease of microbial etiology, whose evolution has a strong relationship with the host's immune response, which occurs in order to contain this infection. The endodontic treatment in these cases has the ultimate biological objective of disinfecting the root canal system to enable repair of the periapical region. This repair is a complex process consisting of hemostasis, inflammation, cell proliferation, maturation and remodeling. Several studies have been carried out in order to relate systemic factors or acquired habits with the development, diagnosis, severity and cure of periradicular lesions. These conditions are referred to as disease modifiers and can clarify the onset of painful symptoms in asymptomatic cases, delayed healing of some lesions, and explain why some properly treated channels result in failure. Hereditary coagulation diseases cause changes in patients' hemostasis, generating a propensity for heavy bleeding and important changes in wound healing. This bibliographic review sought to identify the associations between the most common hereditary coagulation disorders (Hemophilia A and B and von Willebrand's disease) and the repair of endodontic lesions and concluded that such a clinical condition can affect immune responses, interfering with periradicular repair.

Enfermedad von Willebrand: consideraciones prácticas para el odontólogo. Revisión de literatura / von Willebrand disease: practical considerations for the dentist. Literature review

RESUMEN La enfermedad von Willebrand es el desorden hemorrágico hereditario más común, que se origina por la deficiencia del factor von Willebrand, la cual provoca una adhesión y agregación plaquetaria defectuosa. Se caracteriza por un tiempo de sangrado y tiempo parcial de tromboplastina prolongados, con bajos valores del factor VIII, y aumento de fragilidad capilar, pero con recuento normal de plaquetas. El tratamiento odontológico en un paciente con enfermedad von Willebrand, debe ser individualizado de acuerdo con la severidad de la condición del paciente, así como coordinado con el hematólogo, quien debe de determinar el tipo de enfermedad y la necesidad de la terapia de reemplazo del factor según diagnóstico específico previo al manejo de este. Mediante esta revisión bibliográfica se desea reforzar el conocimiento al odontólogo de este trastorno hemorrágico, ya que con ello se pueden evitar o minimizar posibles complicaciones de sangrado durante el tratamiento odontológico.

ABSTRACT von Willebrand disease is the most common inherited bleeding disorder, caused by von Willebrand factor deficiency, which causes defective platelet adhesion and aggregation. It is characterized by a prolonged bleeding time and partial thromboplastin time, with low levels of factor VIII, and increased capillary fragility, but with a normal platelet count. Dental treatment in a patient with von Willebrand disease must be individualized according to the severity of the patient's condition, as well as coordinated with the hematologist, who must determine the type of disease and the need for factor replacement therapy, prior to the patient management. Through this bibliographic review, it wants to reinforce the dentist's knowledge of this bleeding disorder, since this can prevent or minimize possible bleeding complications during dental treatment.

Desmopressin acetate use in von Willebrand's disease: a survey on current practices in Brazil

ABSTRACT Introduction: von Willebrand's disease (VWD) is the most common inherited bleeding disorder. The 1-desamino-8-d-arginine vasopressin (DDAVP) is the treatment of choice for most responsive patients with VWD. The aim of this study was to evaluate DDAVP use in the management of VWD. Method: We implemented a survey targeting medical doctors involved in the management of VWD in Brazil. Data was collected during a national congress on Hematology in November 2017. Main results: A total of 51/80 (63.8%) questionnaires were collected. Most participants (76.2%) were hematologists who assisted adult patients and approximately 60% worked at hemophilia treatment centers (HTCs). Approximately half of participants who reported treating patients with VWD, assisted on average, less than 5 patients per month, and approximately 60% declared not having used any DDAVP for treating VWD in the previous year. However, most participants (70%) prescribed FVIII-containing VWF concentrate (VWF/FVIII) for 1-10 patients in the previous year. More than 80% of the participants recognized the main indications for DDAVP. Physicians who recognized indication for DDAVP for type 1 VWD more often had prescribed DDAVP in previous year (p = 0.03). Barriers for prescribing DDAVP varied and included unavailability of laboratory facilities and consumables for DDAVP testing and lack of skills on its prescription. Conclusion: The DDAVP is currently underused in Brazil, as opposed to the excessive use of VWF/FVIII in VWD patients. We suggest the adoption of measures targeting educational and auditing programs. Furthermore, availability of laboratory reagents is needed to evaluate response and increment the correct use of DDAVP.

Efficacy analysis of von Willebrand factor in human coagulation factor FⅧ concentrates in China / 中国输血杂志

【Objective】 To obtain the quality information of von Willebrand factor (vWF) in coagulation factor Ⅷ (FⅧ) concentrates in China. 【Methods】 FⅧ concentrates produced by 7 domestic blood product manufactures and 1 foreign manufacture were collected, then FⅧ and vWF contained in FⅧ concentrates were evaluated. 【Results】 The activity loss of vWF was more than 25% in 2 of the 7 domestic FⅧ concentrates. The ratio of vWF activity to FⅧ activity in FⅧ concentrates from different domestic manufactures was significantly different (P<0.05). The ratio in FⅧ concentrates prepared by C, D, F manufacturer was greater than 1, which was similar to that in willate@ approved abroad for the treatment of vWD. The ratio in FⅧ concentrates prepared by E manufacturer was greater than 0.7 and less than 1, and by A, B, G manufacturers was less than 0.5. In addition, the specific activities of FⅧ and vWF were significantly different among different FⅧ concentrates in China (P<0.05), and the specific activities of FⅧ and vWF were much lower than that of willate@. 【Conclusion】 The variation of vWF quality between domestic FⅧ concentrates and willate@ is mainly due to the different in vWF content. After the comprehensive consideration of various indicators, the FⅧ concentrates made by C and D manufacturers may be used in the treatment of vWD.

Respuesta a la prueba de desmopresina: estudio de cohorte en un hospital de Bogotá / Response to the desmopressin test: cohort study in a Bogota hospital

Introducción: La desmopresina es un análogo sintético de la vasopresina que aumenta los niveles plasmáticos del factor VIII y del factor de von Willebrand. Algunos autores señalan el tiempo de mantenimiento del efecto hemostático entre 6 y 8 h, por lo que es necesario estudiar su efecto en el tiempo. Objetivo: Determinar la variación de las variables de laboratorio de pacientes con enfermedad de von Willebrand y hemofilia tipo A posterior a la administración de desmopresina. Métodos: Estudio de cohorte retrospectivo en un hospital universitario en Bogotá. Se realizó un muestreo no aleatorio, se incluyeron 24 pacientes mayores de 18 años con diagnóstico de enfermedad de von Willebrand (67 por ciento) y hemofilia tipo A no grave (33 por ciento), a quienes se les realizó la prueba de desmopresina. Se conformaron dos grupos de pacientes, independientemente del diagnóstico: 15 pacientes con valores basales de factor VIII ; 50 UI y 13 pacientes con valores basales de antígeno von Willebrand lt; 50 UI. Se efectúo análisis estadístico descriptivo y correlacional en Stata 13. Resultados: El 87 por ciento de los pacientes del grupo I alcanzó el valor terapéutico a las 2 h de administrada la desmopresina (p= 0,000), el cual se mantuvo hasta 6 h en el 77 por ciento (p= 0,000). En el grupo II el 92 por ciento logró el valor terapéutico en 2 h (p= 0,003), que continuó hasta las 6 h en el 83 por ciento (p= 0,000). Conclusiones: La respuesta a la administración de desmopresina fue máxima a las 2 h posteriores, cuando comenzó a disminuir progresivamente, pero mantuvo el efecto terapéutico. Aunque no se encontraron efectos adversos, existe variabilidad de respuesta entre pacientes(AU)

Introduction: Desmopressin is a synthetic analog for vasopressin that increases the plasma levels of factor VIII and of von Willebrand factor. Some authors indicate maintenance time of hemostatic effect between 6 and 8 hours, so it is necessary to study its effect over time. Objective: To determine the variation of laboratory variables in patients with von Willebrand disease and type A hemophilia after desmopressin administration. Methods: Retrospective cohort study carried out in a university hospital in Bogotá. Nonrandomized sampling was used, including 24 patients older than 18 years and with a diagnosis of von Willebrand disease (67 percent) and non-severe type A hemophilia (33 percent), who underwent the desmopressin test. Two groups of patients were created, regardless of diagnosis: 15 patients with baseline values of factor-VIII 8203; #8203;lower than 50 IU and 13 patients with baseline values of von Willebrand antigen8203;8203;lower than 50 IU. Descriptive and correlational statistical analysis was performed in Stata 13. Results: 87 percent of patients in group I reached the therapeutic value two hours after desmopressin administration (p=0.000), which was maintained for up to six hours in 77 percent (p=0.000). In group II, 92 percent achieved the therapeutic value in two hours (p=0.003), which continued until six hours in 83 percent (p=0.000). Conclusions: Response to desmopressin administration was maximum at two hours, when it began to decrease progressively, but maintained the therapeutic effect. Although no adverse effects were found, there is variability of response among patients(AU)

A rare case of iliopsoas hematoma in a patient with von Willebrand disease

Iliopsoas hematoma is a serious complication that can occur in bleeding disorders, most commonly hemophillia but it can also be seen in von Willebrand disease (vWD) in less frequency. This can cause muscle pain, muscle dysfunction and sometimes even femoral nerve palsy. Iliopsoas hematomas can be diagnosed by the usage of ultrasonography, computed tomography (CT) or magnetic resonance imaging (MRI). Here we report a case of a 20-year-old boy who presented to us with complaints of pain in the right lower quadrant, flank, and inguinal region for a week. He was diagnosed with vWD type 3 when he was 10 years old. The symptoms started after he had tried to kick start his motorbike vigorously. Clinical examination revealed the patient to be in an anti-pain posture and to have tenderness at sites where he complained of pain. A subsequent CT scan showed that there was an iliopsoas hematoma of size 10×6 cm. The patient was managed conservatively with factor replacement and physiotherapy following which there was amelioration in the symptoms and the patient recovered well.

Pregnancy and delivery of a women with Von Willebrand disease type 3: a case report

Von Willebrand disease (VWB) is the most common inherited bleeding disorder, found in approximately 1% of the general population, without ethnic differences. A multidisciplinary team ensuring readiness of availability of blood and blood products, perfect intraoperative hemostatis and administration of timely Von Willebrands factor are essential to prevent complications and improve perinatal outcome.

El papel de la enfermedad de von Willebrand en la hemorragia uterina anormal / Von Willebrand Disease in Abnormal Uterine Bleeding

RESUMEN La hemorragia uterina anormal es un término empleado para las alteraciones en la regularidad, duración y/o volumen de sangrado menstrual y es considerada una causa común de consulta médica y en ocasiones supone un reto diagnóstico para el médico tratante. Dentro del abordaje de la etiología de dicha patología, las coagulopatías afectan alrededor del 13 por ciento de las mujeres, y la más común es la enfermedad de von Willebrand. El objetivo de este trabajo fue realizar una revisión de la literatura científica actual sobre el papel que cumple la enfermedad de von Willebrand en la hemorragia uterina anormal. Esta es una patología hereditaria derivada de una deficiencia del factor von Willebrand encargado de la adhesión plaquetaria. La prevalencia de esta enfermedad puede ser baja, sin embargo, cuando se estudia la población de mujeres con menorragia, la frecuencia puede ir de 5 a 20 por ciento. Se han descrito diferentes problemas ginecológicos asociados a la enfermedad de von Willebrand, tales como menorragia, dismenorrea y una importante deficiencia de hierro asociada a esta, además de una mayor incidencia de quistes ováricos, endometriosis, hiperplasia endometrial y pólipos endometriales. La literatura actual sugiere que se realice tamizaje a aquellas mujeres con cuadro clínico sugestivo. Con respecto al tratamiento la literatura reporta el uso de ácido tranexámico y anticonceptivos orales, pero el que mayor utilidad ha demostrado es la desmopresina(AU)

ABSTRACT Abnormal uterine bleeding is a term used for alterations in the regularity, duration and / or volume of menstrual bleeding and it is considered a common cause of medical consultation; sometimes it is a diagnostic challenge for the treating physician. Within the aetiology approach of said pathology, coagulopathies affect around 13 percent of women, and the most common is von Willebrand disease. The objective is to review the current scientific literature on the influence of von Willebrand disease in abnormal uterine bleeding. This is an inherited pathology derived from a deficiency of the von Willebrand factor responsible for platelet adhesion. The prevalence of this disease may be low, however, when studying the population of women with menorrhagia, the frequency can range from 5 to 20 percent. Different gynecological problems associated with von Willebrand disease have been described, such as menorrhagia, dysmenorrhea and a significant iron deficiency associated with it, in addition to a higher incidence of ovarian cysts, endometriosis, endometrial hyperplasia and endometrial polyps. The current literature suggests that those women with suggestive clinical symptoms should be screened. Regarding treatment, the literature reports the use of tranexamic acid and oral contraceptives, nonetheless desmopressin has proven to be most useful(AU)

Investigation of Von Willebrand disease in children with epistaxis and clinical practical approach

Background: The absence of a standardized approach to the disease and bleeding history can lead to unnecessary patient consultations and sometimes late diagnosis. The aim of this study was to investigate von Willebrand disease (VWD) in patients presenting with epistaxis with clinical practical approach.Methods: 63 Patients who were admitted to the pediatric hematology and oncology clinic between June 2017 and June 2018 with a complaint of epistaxis were evaluated. Patients diagnosed with VWD were classified as group 1, patients without VWD considered as group 2. The two groups were compared in terms of number of additional symptoms, and family history.Results: There was no difference in terms of age and gender when compared with 42 patients not considered as VWD (group 2), number of additional symptoms, and family history were significantly higher in the group considered as VWD.Conclusions: Excess number of additional bleeding symptoms, and bleeding history in family are of importance for the suspicion of diagnosis of VWD for physicians with limited experience in terms of bleeding disorders in primary and secondary health care institutions.

A Multicenter Study on von Willebrand Disease Realities in Yeungnam Region / 임상소아혈액종양

BACKGROUND: von Willebrand disease (VWD) is one of the most common inherited bleeding disorders. However, the number of patients who register to the Korea Hemophilia Foundation (KHF) is much lower than the expected prevalence rate and only few hospitals perform tests for diagnosis autonomously. Thus, we surveyed practical realities of VWD in Yeungnam region. METHODS: Patients with VWD (N=267) who were diagnosed at eleven university hospitals from March 1995 to March 2018 were enrolled in this study. We evaluated the medical records from each hospital retrospectively. RESULTS: Two hundred and twenty-eight children and 39 adults met the diagnostic criteria for VWD. Seventy-eight (57.4%) patients had the blood type O. Fifty-eight patients were definite type 1 (21.7%), 151 were possible type 1 (56.6%), and the others were type 2. Abnormal laboratory findings were the most common factor for the diagnosis in children. VWF mutations were detected in 17 patients. Patients with a family history showed age of diagnosis of 9 y, which is higher than in those with no family history (6 yr), and also showed a higher rate of significant bleeding (32.1% vs. 14.2%). VWF:RCo and VWF:Ag tests were performed in-hospital at only 1 of 11 hospitals. Twelve of 267 patients were enrolled at the KHF (4.5%). CONCLUSION: A high rate of out-sourcing studies may result in inaccurate diagnosis. The registration rate to the KHF is still lower than the prevalence rate. A comprehensive nationwide registration system is necessary in order to identify the actual prevalence rate and promote the diagnosis of VWD in Korea.

Molecular Genetics of von Willebrand Disease in Korean Patients: Novel Variants and Limited Diagnostic Utility of Multiplex Ligation-Dependent Probe Amplification Analyses

BACKGROUND: von Willebrand disease (VWD), characterized by quantitative or qualitative defects of von Willebrand factor (VWF), is the most common inheritable bleeding disorder. Data regarding the genetic background of VWD in Korean patients is limited. To our knowledge, this is the first comprehensive molecular genetic investigation of Korean patients with VWD. METHODS: Twenty-two unrelated patients with VWD were recruited from August 2014 to December 2017 (age range 28 months–64 years; male:female ratio 1.2:1). Fifteen patients had type 1, six had type 2, and one had type 3 VWD. Blood samples were collected for coagulation analyses and molecular genetic analyses from each patient. Direct sequencing of all exons, flanking intronic sequences, and the promoter of VWF was performed. In patients without sequence variants, multiplex ligation-dependent probe amplification (MLPA) was performed to detect dosage variants. We adapted the American College of Medical Genetics and Genomics guidelines for variant interpretation and considered variants of uncertain significance, likely pathogenic variants, and pathogenic variants as putative disease-causing variants. RESULTS: VWF variants were identified in 15 patients (68%): 14 patients with a single heterozygous variant and one patient with two heterozygous variants. The variants consisted of 13 missense variants, one small insertion, and one splicing variant. Four variants were novel: p.S764Efs*16, p.C889R, p.C1130Y, and p.W2193C. MLPA analysis in seven patients without reportable variants revealed no dosage variants. CONCLUSIONS: This study revealed the spectrum of VWF variants, including novel ones, and limited diagnostic utility of MLPA analyses in Korean patients with VWD.

Cuidado odontológico de pacientes con trastornos hereditarios de la coagulación / Dental care for coagulation hereditary disorder patients

Resumen Los trastornos hereditarios de la coagulación como la hemofilia que es una enfermedad genética ligada al cromosoma X que se manifiesta por la deficiencia de los factores de la coagulación VIII, IX y XI -Hemofilia A, B y C respectivamente. , de acuerdo a la cantidad de deficiencia de estos se clasifican en leve, moderada o severa. Otra de enfermedad que se ve relacionada al trastorno de la coagulación es conocida como enfermedad de Von Willebrand cuya proteína con el mismo nombre se encuentra ausente o disminuido, otro aspecto a resaltar es que esta enfermedad no se encuentra ligada al sexo. El correcto diagnóstico clínico y exámenes de laboratorio, hace parte de un número de pasos que debe tener en cuenta el odontólogo para realizar normas de atención adecuadas según el tratamiento de cada paciente, ya sea consulta programada para realizar procedimientos como: operatoria, endodoncia, periodoncia, exodoncias, procedimientos de cirugía oral; O que se deba realizar tratamientos de urgencias como: heridas de la mucosa, laceraciones en boca, trauma facial, abscesos o celulitis, trauma dentoalveolar, enfocándose no solo en la parte clínica sino en el adecuado manejo del dolor de cada paciente.

Abstract Hereditary disorders of coagulation are genetic disease, among them are hemophilia that is attached to the X chromosome, so it manifests itself in men; In them there is deficiency of coagulation factors VIII, IX and XI -Hemofilia A, B and C respectively-, according to the amount of deficiency of these are classified as mild, moderate or severe. Another disease that is related to the coagulation disorder is known as Von Willebrand disease whose protein with the same name is absent or diminished, another aspect to emphasize is that this disease is not linked to sex. The correct clinical diagnosis and laboratory tests are part of a number of steps that the dentist must take into account to make adequate standards of care according to the treatment of each patient, whether scheduled consultation to perform procedures such as: surgery, endodontics, periodontics , dental extractions, oral surgery procedures; Or that it is necessary to carry out emergency treatments such as: mucosal wounds, lacerations in the mouth, facial trauma, abscesses or cellulitis, dentoalveolar trauma, focusing not only on the clinical part but also on the adequate management of the pain of each patient.

A Multicenter Study on Korean von Willebrand Disease Realities / 임상소아혈액종양

BACKGROUND: von Willebrand disease (VWD) is the most common inherited bleeding disorder with a prevalence of up to 1%. However in Korea, only 126 VWD patients were registered in Korea Hemophilia Foundation (KHF). The aim of this study was to determine the status of VWD patients in Korea. We analyzed VWD patients by age, gender, blood group, family history and bleeding history.METHODS: One hundred twenty-six VWD patients registered in the KHF by December 2016, and 74 patients diagnosed at six university hospitals were enrolled in this study. We evaluated the medical records from the KHF and the questionnaires from six university hospitals retrospectively.RESULTS: Seventeen patients misdiagnosed and ten patients duplicated were excluded. One hundred nine patients registered in the KHF and 64 patients diagnosed at six university hospitals met the criteria for VWD. The blood type O accounts for 72 (51.8%). VWF mutation was detected in 30 patients (17.3%). Median age at diagnosis was 10.5 yr. The bleeding score of adults was higher than that of children (P < 0.001). The most common bleeding symptom was epistaxis (48.5%). The distribution of VWD types was: 67% of type 1, 30.1% of type 2, and 2.9% of type 3.CONCLUSION: Even though only six hospitals responded to the survey, 64 patients not registered in the KHF were diagnosed with VWD. Our results suggest the prevalence of Korean VWD might be higher than previously reported. A nationwide registration system is warranted in order to accurately identify the national prevalence of VWD.

Surgery in Patients with Von Willebrand Disease : A Single Center Experience / 임상소아혈액종양

BACKGROUND: Von Willebrand disease (VWD) is the most common inherited bleeding disorder. Surgery, even relatively minor procedures, in patients with moderate to severe qualitative and quantitative deficiencies of von Willebrand factor (VWF) can be associated with a life-threatening risk of excessive bleeding. The purpose of this study was to evaluate the safety and efficacy of VWF/FVIII in patients with von Willebrand disease before surgery and determine the efficacy of VWF/FVIII.METHODS: We reviewed the results of surgical procedures in patients with VWD at Kyung Hee University Hospital at Gangdong, between September 2009 and January 2016. VWF/FVIII concentrates were administrated preoperatively to all patients.RESULTS: Between September 2009 and January 2016 at our center, eight surgical procedures were performed successfully and no severe complications were observed in the seven patients with VWD. Four orthopedic procedures, one laparoscopic appendectomy, one ovary cystectomy, one strabotomy, and one dental extraction were performed. The median duration of hospitalization was seven days. VWF/FVIII concentrates were administered prior to all procedures, including the dental extraction. In all cases, uncontrolled bleeding and thromboembolic complications were not observed.CONCLUSION: Patients with VWD who require surgery can be treated efficiently and safely with VWF/FVIII concentrates. There is excellent tolerance, efficacy and safety in preventing excessive bleeding during surgery. When administering VWF/FVIII concentrates, treatment should be monitored with VWF Ag, VWF:RCo and FVIII plasma levels.

Diagnóstico laboratorial de coagulopatías hemorrágicas en pacientes del Hospital Nacional de Itauguá / Laboratory diagnosis of hemorrhagic coagulopathies in patients of the National Hospital of Itauguá

Introducción: la hemostasia es el conjunto de sistemas que actúan coordinadamente para mantener la integridad de los vasos sanguíneos y la fluidez de la sangre; la alteración puede desencadenar trastornos trombóticos o hemorrágicos, dependiendo de la naturaleza de la falla. Objetivos: describir las coagulopatías hemorrágicas que se registraron en el departamento de laboratorio del Hospital Nacional de Itauguá, desde julio 2014 hasta diciembre 2015, obtener frecuencia y datos demográficos, edad, sexo, procedencia y clasificar las coagulopatías según deficiencias de factores de la coagulación, vía extrínseca, vía intrínseca y vía común final; sospecha de inhibidores adquiridos y enfermedad de von Willebrand. Material y Métodos: diseño observacional, descriptivo, retrospectivo de corte trasverso; incluyéndose pacientes de ambos sexos, todas las edades, derivados de médicos hematólogos. Resultados: se registraron 77 pacientes con coagulopatías hemorrágicas en el Laboratorio, 43 fueron del sexo masculino, de 1 a 75 años, mediana 18 años; 31% (24/77) con deficiencias del factor VII, todos leves, edades 7 a 75 años. En la vía intrínseca, la deficiencia del factor VIII o Hemofilia A, fue la más observada 29%(22/77), mayoría severas (13/22), mientras que déficit de factor IX, Hemofilia B, en 4 pacientes 5%(4/77). 85% Hemofilia A y 15% Hemofilia B, edades 1 y 64 años, mediana 13,5 años, todos del sexo masculino; no se registraron deficiencias de FXI y FXII en el periodo de estudio. De la vía común final, se encontraron 3 pacientes con hipofibrinogenemia, 1 con probable disfibrinogenemia, 1 con déficit de Factor II, 2 de Factor V y 2 de Factor X, 2 adultas, y el resto pediátricos; estas deficiencias son muy poco frecuentes, Factor I, V y X de 1/1.000.000 y FII 1/2.000.000 personas. Quince pacientes con sospecha de inhibidores, dos de ellas con inhibidor específico anti-FVIII, y probables inhibidores de interferencia. Se confirmó el primer déficit de factor Von Willebrand, en una mujer de 47 años. Conclusiones: entre las coagulopatías hemorrágicas de mayor frecuencia, se encuentran las Hemofilias A y B, seguida de deficiencias del factor VII y probables inhibidores de interferencia, los dos casos de inhibidores específicos anti Factor VIII fueron en pacientes con Hemofilia A severa. Fue relevante también el hallazgo de deficiencias de la vía común de la coagulación, a pesar de ser poco frecuentes. Algunos pacientes fueron diagnosticados en edad adulta, reflejando lo tardío que se llega al diagnóstico en el país.

Introduction: hemostasis is the set of systems that work in concert to maintain the integrity of blood vessels and blood flow; alteration can trigger thrombotic disorders or bleeding, depending on the nature of the fault Objective: describe hemorrhagic coagulopathy registered in the Medical Laboratory Department diagnosis at the National Hospital of Itauguá, from July 2014 to December 2015, obtain frequency and demographics, age, sex, origin and classify coagulopathy in to deficiencies of coagulation factors of the extrinsic pathway, intrinsic pathway, and common pathway; suspicion acquired inhibitors and von Willebrand's disease. Material and Methods: the design was an observational, descriptive, retrospective cross sectional study; being including patients of both sexes, all ages, referred by hematologists. Results: 77 patients with hemorrhagic coagulopathies, were female 43 male and 34 female, from 1 to 75 years, median age of 18 years; 31% (24/77) with factor VII deficiency, all mild, ages 7 to 75, 1 / 500,000 appears. In the intrinsic pathway, the factor VIII deficiency or hemophilia A, was the most observed 29% (22/77) severe majority (13/22), while Factor IX deficit, Hemophilia B, in 5% of patients (4/77). 85% Hemophilia A, and 15% Hemophilia B, ages 1 to 64 years, median age of 13.5 years, all male; no FXI and FXII deficiencies were recorded in the study period.Of the final common pathway, 3 patients with hipofibrinogenemia were found, 1 probable dysfibrinogenaemia, 1 deficiency of FII, 2 FV and FX 2, 2 were adult and the rest were pediatric; these deficiencies are rare, FI, V and X of 1 / 1,000,000 and FII 1 / 2,000,000 people. Fifteen patients with suspected inhibitors adquired, two of them with anti-FVIII specific inhibitor, and probable interference inhibitors. The first von Willebrand, factor deficiency was confirmed in a woman of 47 years. Conclusions: among the most frequent hemorrhagic coagulation disorders, we found hemophilia A and B, followed by deficiencies of factor VII and probable interference inhibitors both cases of specific inhibitors of factor VII were found in patients with severe Hemophilia A. Some patients were diagnosed in adulthood

Surgery in Patients with Von Willebrand Disease : A Single Center Experience / 임상소아혈액종양

BACKGROUND: Von Willebrand disease (VWD) is the most common inherited bleeding disorder. Surgery, even relatively minor procedures, in patients with moderate to severe qualitative and quantitative deficiencies of von Willebrand factor (VWF) can be associated with a life-threatening risk of excessive bleeding. The purpose of this study was to evaluate the safety and efficacy of VWF/FVIII in patients with von Willebrand disease before surgery and determine the efficacy of VWF/FVIII. METHODS: We reviewed the results of surgical procedures in patients with VWD at Kyung Hee University Hospital at Gangdong, between September 2009 and January 2016. VWF/FVIII concentrates were administrated preoperatively to all patients. RESULTS: Between September 2009 and January 2016 at our center, eight surgical procedures were performed successfully and no severe complications were observed in the seven patients with VWD. Four orthopedic procedures, one laparoscopic appendectomy, one ovary cystectomy, one strabotomy, and one dental extraction were performed. The median duration of hospitalization was seven days. VWF/FVIII concentrates were administered prior to all procedures, including the dental extraction. In all cases, uncontrolled bleeding and thromboembolic complications were not observed. CONCLUSION: Patients with VWD who require surgery can be treated efficiently and safely with VWF/FVIII concentrates. There is excellent tolerance, efficacy and safety in preventing excessive bleeding during surgery. When administering VWF/FVIII concentrates, treatment should be monitored with VWF Ag, VWF:RCo and FVIII plasma levels.

A Multicenter Study on Korean von Willebrand Disease Realities / 임상소아혈액종양

BACKGROUND: von Willebrand disease (VWD) is the most common inherited bleeding disorder with a prevalence of up to 1%. However in Korea, only 126 VWD patients were registered in Korea Hemophilia Foundation (KHF). The aim of this study was to determine the status of VWD patients in Korea. We analyzed VWD patients by age, gender, blood group, family history and bleeding history. METHODS: One hundred twenty-six VWD patients registered in the KHF by December 2016, and 74 patients diagnosed at six university hospitals were enrolled in this study. We evaluated the medical records from the KHF and the questionnaires from six university hospitals retrospectively. RESULTS: Seventeen patients misdiagnosed and ten patients duplicated were excluded. One hundred nine patients registered in the KHF and 64 patients diagnosed at six university hospitals met the criteria for VWD. The blood type O accounts for 72 (51.8%). VWF mutation was detected in 30 patients (17.3%). Median age at diagnosis was 10.5 yr. The bleeding score of adults was higher than that of children (P < 0.001). The most common bleeding symptom was epistaxis (48.5%). The distribution of VWD types was: 67% of type 1, 30.1% of type 2, and 2.9% of type 3. CONCLUSION: Even though only six hospitals responded to the survey, 64 patients not registered in the KHF were diagnosed with VWD. Our results suggest the prevalence of Korean VWD might be higher than previously reported. A nationwide registration system is warranted in order to accurately identify the national prevalence of VWD.

Factor von Willebrand y Enfermedad de von Willebrand: nuevos enfoques diagnósticos / Von Willebrand Factor and von Willebrand disease: new approaches to diagnosis / Fator Von Willebrand e doença de von Willebrand: novas abordagens diagnósticas

El factor von Willebrand (VWF) es una glicoproteína que se sintetiza en células endoteliales y en megacariocitos. Su vida media es de ~12 horas. Está formado por multímeros de diferentes pesos moleculares, pequeños, intermedios, grandes y extragrandes. La actividad funcional reside en los multímeros grandes, y los extragrandes son trombogénicos. Promueve la adhesión plaquetaria al subendotelio, la agregación plaquetaria y transporta al FVIII en plasma, protegiéndolo de su degradación por proteasas. La enfermedad de von Willebrand es el trastorno hemorrágico más frecuente; se describen deficiencias cuantitativas (parcial: VWD1; total: VWD3) o defectos cualitativos (VWD2A, VWD2M, VWD2B y VWD2N). La expresión clínica es variable (sangrado muco-cutáneo) y su herencia autosómica, dominante o recesiva, según las variantes. Los niveles del VWF dependen de factores genéticos y no genéticos que afectan el diagnóstico y la expresión clínica. Para llegar al diagnóstico se precisan varias pruebas, algunas inespecíficas. El laboratorio comienza con pruebas orientadoras, se continúa con pruebas confirmatorias, y posteriormente pruebas para definir la variante de VWD. El diagnóstico genotípico es fundamental para lograr el diagnóstico diferencial entre VWD2B vs. PT-VWD y VWD2N vs. Hemofilia A (leve-moderada), diferenciar VWD de AVWS y discriminar variantes VWD2.

Von Willebrand factor (VWF) is a glycoprotein with essential roles in both primary and secondary hemostasis, synthesized by endothelial cells and megakaryocytes. Its half-life is ~12 hours. VWF consists in multimers of different molecular weight: small, intermediate, large and ultra large. The functional activity resides in the large multimers; the ultra large are thrombogenic. VWF promotes platelet adhesion to subendothelium, platelet aggregation and binds FVIII, protecting it from proteolysis and preserving its hemostatic function. Von Willebrand disease is the most common bleeding disorder; qualitative defects (VWD2A, VWD2M, VWD2B and VWD2N) and quantitative deficiencies (VWD1 and VWD3) are described. The clinical expression is variable (mucocutaneous bleeding); VWF levels depend on genetic and non-genetic factors affecting diagnosis and clinical expression. The inheritance can be autosomal, dominant or recessive according to the variants. To reach diagnosis, several tests are required, being some of them unspecific. The laboratory testing begins with global tests, followed by confirmatory tests and further tests to define the variant of VWD. Genotypic studies are essential to achieve the differential diagnosis between VWD2B vs. PT-VWD, VWD2N vs. Hemophilia A (mild to moderate) and differentiate VWD from AVWS and discriminate VWD2 variants.

O fator de von Willebrand (vWF) é uma glicoproteína sintetizada em células endoteliais e em megacariócitos. Sua vida média é de ~12 horas. É constituído por multímeros de pesos moleculares diferentes, pequenos, intermediários, grandes e extragrandes. A atividade funcional reside nos multímeros grandes, sendo os extragrandes, trombogênicos. Promove adesão das plaquetas ao subendotélio, a agregação plaquetária e transporta o FVIII em plasma, protegendo-o de sua degradação. A doença de von Willebrand é o distúrbio hemorrágico mais frequente; são descritas deficiências quantitativas (parcial: VWD1; total: VWD3) ou defeitos qualitativos (VWD2A, VWD2M, VWD2B e VWD2N). A expressão clínica é variável, (sangramento mucocutâneo), e sua herança autossômica dominante ou recessiva de acordo com as variantes. Os níveis de vWF dependem de fatores genéticos e não-genéticos que afetam o diagnóstico e a expressão clínica. Para fazer o diagnóstico, vários testes são necessários, alguns inespecíficos. O laboratório começa com testes orientadores, continua com testes de confirmação e, mais tarde, com testes para definir a variante de VWD. O diagnóstico genotípico é essencial para alcançar o diagnóstico diferencial entre VWD2B vs. PT-VWD e VWD2N vs. Hemofilia A (leve a moderada), diferenciar VWD de AVWS, discriminar variantes VWD2.