Exsanguinating bleeding following tooth extraction in a 12-year-old girl: a rare case of acquired haemophilia A

Acquired Haemophilia A: An Intriguing Disease

Abstract. Acquired Haemophilia A is a rare acquired bleeding disorder caused by Factor VIII autoantibodies, which neutralise FVIII activity. These inhibitors differ from alloantibodies against FVIII, which can occur in congenital Haemophilia A after repeated exposures to plasma-derived or recombinant FVIII products. In most cases, the disease occurs suddenly in subjects without a personal or familiar history of bleedings, with symptoms that may be mild, moderate, or severe. However, only laboratory alterations are present in ~ 30% of patients. The incidence varies from 1 to 4 cases per million/year; more than 80% of patients are elderly, males and females are similarly affected. There is a small peak of incidence related to pregnancy in young women aged 20–40 years. The disease may be underdiagnosed in the elderly. The diagnostic algorithm is based on an isolated prolonged activated partial thromboplastin time, normal thrombin time, absence of Lupus Anticoagulant, and a mixing test that reveals the presence of an inhibitor: the finding of reduced FVIII activity and the detection of neutralising autoantibodies against FVIII lead to the diagnosis. The disease is idiopathic in 44%–63% of cases, while in the others etiological factors are present. Bleeding prevention and treatment are based on therapeutic tools as by-passing agents, recombinant porcine FVIII concentrate or, in a limited number of cases, FVIII concentrates and desmopressin. As soon as the diagnosis has been made, immunosuppressive therapy must be started to eradicate the inhibitor. Better knowledge of the disease, optimal management of bleeding and eradication of the inhibitor have significantly reduced morbidity and mortality in most patients.

A Case of a Patient Who Is Diagnosed with Mild Acquired Hemophilia A after Tooth Extraction Died of Acute Subdural Hematoma due to Head Injury

Background

Acquired hemophilia A (AHA) is a rare disorder which results from the presence of autoantibodies against blood coagulation factor VIII. The initial diagnosis is based on the detection of an isolated prolongation of the activated partial thromboplastin time (aPTT) with negative personal and family history of bleeding disorder. Definitive diagnosis is the identification of reduced FVIII levels with evidence of FVIII neutralizing activity.

Case report

We report a case of a 93-year-old female who was diagnosed as AHA after tooth extraction at her home clinic. Prolongation of aPTT and a reduction in factor VIII activity levels were observed with the presence of factor VIII inhibitor. AHA condition is mild. However, acute subdural hematoma of this patient occurred due to an unexpected accident in our hospital. Hematoma was gradually increased and the patient died 13 days after admission.

Discussion

Although AHA is mild, intracranial bleeding is a life-threatening condition. We also should pay attention to the presence of AHA patients when we extract teeth.

Bleeding during and after dental extractions in patients with liver cirrhosis

Little is known about the prevention and management of acquired coagulopathies, such as those affecting cirrhotic patients. The objective of this analytic retrospective observational study was to evaluate patients on the liver transplant waiting list according to the following outcomes: (1) presence of unusual intraoperative bleeding (>10min after routine haemostatic procedures); and (2) presence of postoperative haemorrhagic complications. The outcomes were analysed according to clinical and laboratory variables. A total of 190 visits were performed for extraction of 333 teeth (ranging from 1 to 9 teeth per visit), with platelet count ranging from 16,000 to 216,000 and international normalized ratio (INR) below 3. Twelve cases (6.31%) had unusual intraoperative bleeding and 12 had postoperative haemorrhagic complications. All the events were controlled by local measures. Intraoperative bleeding was associated with low count of platelets (P=0.026). However, this counting could explain only 16% (adjusted R²=0.16) of the cases of bleeding (P=0.44), meaning that platelet function changes might be involved. Our results show that cirrhotic patients presenting platelet count above 16,000 and INR below 3 need no previous blood transfusion, with local measures being enough to manage haemorrhagic events.