Laboratory Diagnosis of von Willebrand’s Disease

Inherited bleeding disorders in dermatologic surgery

BACKGROUND

A patient referred for Mohs micrographic surgery of a basal cell carcinoma had a history of a congenital clotting factor IX deficiency requiring recombinant factor IX replacement.

OBJECTIVE

To examine the management and problems associated with cutaneous surgery in patients with inherited clotting factor deficiencies.

METHODS

Case report and review of the medical literature.

RESULTS

Reconstructive options must be carefully chosen to minimize bleeding in patients with clotting factor deficiencies. Preoperative consultation with a hematologist and coagulation factor replacement both before and after cutaneous surgery prevent excessive hemorrhage.

CONCLUSION

Meticulous attention to hemostasis, careful preoperative assessment, and postoperative follow-up minimize complications in patients with known coagulation deficiencies who require cutaneous surgery.

Successful treatment with recombinant factor VIIa of therapy-resistant severe bleeding in a patient with acquired von Willebrand disease

We describe an elderly man who presented with life-threatening hematuria and gastrointestinal bleeding caused by acquired von Willebrand disease associated with monoclonal gammopathy of undetermined significance (MGUS). Standard therapy with desmopressin, von Willebrand factor-containing factor VIII concentrate, tranexamic acid, and immunoglobulin failed to achieve adequate hemostasis. However, treatment with recombinant activated factor VII (rFVIIa) arrested the bleeding completely. Since acquired von Willebrand disease can lead to life-threatening hemorrhage, clinicians should consider rFVIIa as an effective treatment option if standard therapy fails.

Perioperative management of von Willebrand's disease in otolaryngologic surgery

von Willebrand's disease (VWD) is the most common hereditary bleeding disorder. Unchecked or improperly managed, VWD-associated hemorrhage can lead to catastrophic surgical outcome. Based on the authors' recent experience with 21 procedures in 12 patients, a contemporary protocol for successful perioperative management of VWD in otolaryngologic surgery is presented. In patients with VWD type 1 or 2a, desmopressin, a synthetic vasopressin analog, is administered both pre- and postoperatively to release von Willebrand factor (VWF) from storage sites. In type 2b or 3, a factor VIII concentrate rich in VWF is administered. In addition, a 10- to 14-day course of intravenous and/or oral Amicar (Immunex Corp., Seattle, WA) may be prescribed postoperatively. Intraoperatively, the surgical laser is used to further decrease blood loss and augment hemostasis. This medical and surgical protocol minimizes the risk of hemorrhage and of transfusion-related complications through the judicious use of preoperative and postoperative coagulation replacement products. Using these guidelines in a variety of otolaryngologic cases, the authors have had no bleeding complications at their institution.

Acquired von Willebrand disease: concise review of occurrence, diagnosis, pathogenesis, and treatment

Acquired von Willebrand disease (AvWD) is a rare complication of an autoimmune or neoplastic disease. It is associated mostly with a lymphoid or plasma cell proliferative disorder. The clinical manifestations are similar to congenital von Willebrand disease. Diagnosis is confirmed by the demonstration of decreased levels of factor VIII coagulant activity (VIII:C), ristocetin cofactor activity (vWF:RCo), and von Willebrand factor (vWF) antigen (vWF:Ag). vWF multimer analysis usually reveals a type II defect with decreased abundance of higher molecular weight vWF multimers. Various pathogenetic mechanisms have been described, including the development of anti-vWF antibodies and adsorption of vWF by tumor cells. Successful management approaches have included treatment of the underlying disorder, infusion of high-dose gamma globulin, replacement therapy with factor VIII/vWF concentrates, intravenous infusion of desmopressin, and administration of corticosteroids.