Desmopressin testing in haemophilia A patients and carriers

Introduction: Desmopressin (DDAVP) testing (DT) in patients (pts) with haemophilia A (HA) and carriers (CHA) is up to now not standardized. This prompted us to evaluate results of DT carried out between 1996 and 2011 in centres of the Competence Network Haemorrhagic Diatheses East. Patients and method: An increase of the factor VIII activity (FVIII) above 50% or at least the two fold of initial values within 120 min after DDAVP was defined as complete response (CR). Data from 80 patients (31 children, 49 adults) of whom 64 suffered from HA (sub-HA: n=48; mild: n=14; moderate: n=2) and 16 patients CHA were evaluated. Results: In 34 patients DDAVP was given i.v. (dose range: 0.26–0.6 µg/kg body weight, mean: 0.33), in 31 intranasally (i.n. 300–600 µg) and in 15 s.c. (15–40 µg). The maximal FVIII increase was reached 60 min after DDAVP. For i.v. application the mean FVIII increase was 3.1-fold, for i.n. 2.1-fold and for s.c. 2.4-fold. A CR was detected in 71 patients, a non-response in 9. Mild side effects such as flush, headaches or nausea were observed in 11 patients (14%). Conclusion: For desmopressin testing in patients with haemophilia A and carriers i.v. application at 0.3 µg/kg body weight and the determination of FVIII before and 60 min after desmopressin infusion is recommended.