von Willebrand's disease in Mexico: a pilot study

Abstract

von Willebrand's disease (VWD) is the most commonly inherited bleeding disorder. For a long time, it has been said that VWD was absent in some countries due to ethnical differences. Information about the prevalence of VWD in Mexico remains unclear, owing largely to poor awareness and diagnosis of the disease. The aim of this study was to objectively diagnose VWD in a cohort of highly selected Mexican patients with a chronic history of bleeding. Mexican Mestizos were recruited between July 2010 and August 2011. Included were 133 adult and paediatric patients with a high suspicion of VWD. Fifty-three were diagnosed with VWD: 47 (88.7%) with type 1 VWD, four (7.5%) with type 2a VWD and two (3.8%) with type 3 VWD. Mean age for female patients was 19.5 years (range 3-44 years) and 18.5 years (range 4-63 years) for male patients. Mean age at start of bleeding symptoms was 8.8 years (range 1-61). The most frequent clinical symptoms were epistaxis (84.9%), ecchymosis (79.2%), haematomas (71.7%), gum bleeds (62.3%) and petechia (50.9%). Severe transoperative or postoperative bleeding was found in 17 patients (32.1%). Twenty-six women at childbearing age had a history of abnormal gynaecological bleeding. Our results clearly demonstrate the presence of VWD in Mexican and underscore the importance of a more detailed description of VWD. Efforts to increase the awareness and diagnosis of VWD could help in better identification of patients with bleeding disorders and lead to early, appropriate management with safe and efficacious therapies such as desmopressin and plasma concentrates.

von Willebrand Disease and other hereditary haemostatic factor deficiencies in women with a history of postpartum haemorrhage

“…This is the case of Mexico where VWD has been largely unrecognized and underdiagnosed. 19 Along with the lack of specific clinical symptomatology, other TA B L E 1 General characteristics of women with and without PPH modified by genetic and environmental factors such as the ABO blood group, which accounts for approximately 30% of the variability. 33 Most important for the purposes of this study is the fact that pregnancy is not the best moment to perform an accurate diagnosis of a haemostatic disorder.…”

“…and controls according to a described technique 18 with slight modifications previously described. 19…”

“…Unfortunately, and tragically, as occurred in other developing nations, a decrease of this public health problem was only 1.5% 25. This is the case of Mexico where VWD has been largely unrecognized and underdiagnosed 19. In general, national and local guidelines published address the obstetric problem while the haemostatic problem is regarded at later stages in the treatment of PPH.…”

“…The VWF multimeric test was performed in all patients and controls according to a described technique18 with slight modifications previously described 19. Values of platelet aggregation <60% are considered abnormal.…”

Enfermedad de von Willebrand, biología molecular y diagnóstico

“…1), como la variante «Vicenza» (c.3614G>A) en el exón 27, que provoca un cambio de una arginina por una histidina en la posición 1205 del VWF y con ello disminuye el tiempo en que el VWF permanece en el plasma; esta mutación es una de las más estudiadas y se relaciona con la enfermedad de von Willebrand tipo 1 40,41 . Incluso existe un estudio molecular del gen VWF en pacientes mestizos mexicanos, en el que se describen 3 nuevas mutaciones: E1447Q en un paciente con la enfermedad de von Willebrand tipo 1 y diabetes; P2781S en un paciente con tipo 2M; y P812L en otro paciente tipo 1/2N 22,42 . Este alto grado de polimorfismos en el VWF, junto con el gran tamaño del gen y la presencia de un seudogén parcial, hacen que la secuenciación completa del gen y la interpretación de datos sean difíciles y complejas.…”