Detection of mild hemophilia by preoperative screening with APTT test

Abstract

Mild hemophilia is sometimes overlooked in the diagnosis even in patients with findings of a slightly prolonged APTT. Therefore, we planned to clarify the frequencies of mild hemophilia in patients with normal PT and prolonged APTT before surgery. Among the 11,465 patients who underwent surgery from 1 June 2015 to 31 May 2016 in Okayama University Hospital, 8,676 patients were administered the preoperative APTT test. All the patients who received the anticoagulant treatment were excluded. We decided that the reference APTT range was 26.9–38.1 seconds on the basis of the normal distribution of normal samples, and patients with an APTT of 38.2 seconds or longer were recruited as the subjects of this study. Among these patients, 134 (1.5%) showed APTTs beyond the upper reference range (38.2 seconds or longer). However, only 13 patients (9.7%) were subjected to further investigation; as a result, one patient was found to have von Willebrand disease (type I) and another one with mild hemophilia A. They were 0.012% each of the total 8,676 patients. These results suggest that a certain percentage of mild hemophilia patients existed in the general population and they were unaware of their bleeding disorder before surgery. Therefore, it is very important to call a physician’s attention to the possibility of mild hemophilia. Moreover, there is concern that blood coagulation disorders are not tracked because of insufficient scrutiny. A much larger study is required to clarify the actual percentage of patients with mild hemophilia in the Japanese population.