Abstract
Objective : Patients with hemophilia may show only a slight prolongation of the activated partial thromboplastin time (APTT) and the diagnosis may be overlooked during conventional preoperative testing. In the present study, an attempt was made to ensure identification of patients with latent hemophilia by setting the APTT cutoff value at 35.1 s (reference cutoff value at our hospital, 40.0 s) during testing prior to planned surgery.
Method : The subjects comprised 445 patients who underwent testing of the coagulation profile prior to planned surgery between April 1, 2011 and November 30, 2013. A detailed medical history was obtained from the patients with APTT ≥35.1 s ; those who gave no history of coagulation abnormalities were excluded. All the remaining patients were subjected to further testing (prothrombin time, repeat APTT, fibrinogen, antithrombin III, double-filtration plasmapheresis, D-dimer, and factor VIII, IX, and vW activity) to confirm the presence or absence of hemophilia.
Results : The APTT was ≥35.1 s in 40 patients (9.0%), of which 10 were excluded based on their negative medical history. The final diagnoses of the remaining 30 patients were as follows : no coagulation abnormalities, n=28 ; normalization during follow-up, n=1 ; hemophilia A, n=1. The patient with hemophilia A had no family history and the initial APTT value was within the reference cutoff value at 39.5 s.
Conclusion : Efforts must be made to ensure preoperative identification of patients who may have undiagnosed latent hemophilia. Screening using an APTT cutoff value lower than the current reference value is required in order to ensure identification during preoperative testing.
