We describe a 10-year-old severe hemophilia B boy with a stop codon mutation of exon 2 in the factor IX gene who developed high inhibitor of 70 Bethesda units (BU) from 12 months of age after exposure to prothrombin complex concentrate for 14 days. The inhibitor spontaneously disappeared within 3 months. The patient, however, exhibited anaphylactic reaction to the administration of prothrombin complex concentrate and factor IX concentrate at ages 15 and 23 months, respectively. Although recombinant activated factor VII was alternatively given, he suffered from progressive hemophilic arthropathy. At the age of 10 years, the boy underwent desensitization to factor IX concentrate and could tolerate factor IX concentrate of 40 U/kg administered on day 9 of desensitization. Unfortunately, the inhibitor of 16 BU was detected on day 6 and rapidly increased to 180 BU on day 9 of desensitization. Rituximab 375 mg/m2 per week was therefore immediately initiated on day 10 and a total of four doses were given. The inhibitor gradually decreased to 21.5 BU after the fourth dose of rituximab. The daily factor IX concentrate administration of 40 U/kg was continued for 1 month and decreased to three times per week for another month, and then to once to twice per week for the remaining 14 months of desensitization. The patient was able to attend regular school and the most recent inhibitor ranged from 4.4 to 10 BU. No proteinuria or alteration of renal function was found. In conclusion, rituximab is a helpful adjuvant to immune tolerance therapy in a hemophilia B boy with inhibitor and anaphylaxis to factor IX concentrate.

We report a haemophilia A boy with high inhibitor titre (170 BU) who experienced five lifethreatening bleeding episodes during a one-year period from 9 to 21 months. At the age of 22 months, he received rituximab (375 mg m )2 per dose) at one-and three-week intervals, three courses each and alternative daily treatment with factor VIII concentrate at doses of 100 units kg )1 for 24 weeks and 50 units kg )1 for the following 28 weeks. Although the pretreatment inhibitor level of 4.5 BU showed an anamnestic response reaching the maximum level of 200 BU at the 9th week of treatment, it gradually declined to 30 BU at the 22nd week and was constantly maintained at 25-30 BU for the following 30 weeks. Only three bleeding episodes of two haematomas and one haemarthrosis were found during the one-year treatment period. No opportunistic infection occured during this period.

Aims: To compare insulin sensitivity, β-cell function and iron status biomarkers in non-transfusion-dependent thalassaemia (NTDT) with iron excess during pre- and post-iron chelation. Methods: Subjects with NTDT, aged older than 10 years, with serum ferritin >300 ng/ml, were included. Iron chelation with deferasirox (10 mg/kg/day) was prescribed daily for 6 months. Results: Ten patients with a median age of 17.4 years were enrolled. The comparison between pre- and post-chelation demonstrated significantly lower iron load: median serum ferritin (551.4 vs. 486.2 ng/ml, p = 0.047), median TIBC (211.5 vs. 233.5 µg/dl, p = 0.009) and median non-transferrin binding iron (5.5 vs. 1.4 µM, p = 0.005). All patients had a normal oral glucose tolerance test (OGTT) both pre- and post-chelation. However, fasting plasma glucose was significantly reduced after iron chelation (85.0 vs.79.5 mg/dl, p = 0.047). MRI revealed no significant changes of iron accumulation in the heart and liver after chelation, but there was a significantly lower iron load in the pancreas, assessed by higher T2* at post-chelation compared with pre-chelation (41.9 vs. 36.7 ms, p = 0.047). No adverse events were detected. Conclusions: A trend towards improving insulin sensitivity and β-cell function as well as a reduced pancreatic iron load was observed following 6 months of iron chelation (TCTR20160523003).