Development of Haemophilia Treatment in the Eastern Part of Germany over the Last Decade in the Kompetenznetz Hämorrhagische Diathese Ost (KHDO).

INTRODUCTION: In 2005 the Kompetenznetz Hämorrhagische Diathese Ost published epidemiologic data about patients with haemophilia A (HA) and haemophilia B (HB) in the eastern part of Germany. This study provides data about the development of treatment in these patients over the past 10 years. METHODS: Data from 12 haemophilia centres in eastern Germany were retrospectively collected for the year 2015 from patients' records. RESULTS: We evaluated 413 patients (115 children, 298 adults) with HA or HB. A total of 286 patients (69.2%) had severe haemophilia (patients with severe haemophilia, PWSH). Compared with 2005, the proportion PWSH on prophylaxis increased from 90% to 98.8% in children and from 64% to 80.2% in adults. The use of plasma-derived factor concentrates decreased from >70% to 55.3% in children and to 55.1% in adults. Mean annual factor consumption in PWSH without inhibitor was higher in 2015 compared with 2005 (children with HA: 151,489 vs. 98,894; adults with HA: 217,151 vs. 151,394; children with HB: 105,200 vs. 64,256; adults with HB: 159,185 vs. 85,295). Median annualized bleeding (annualized bleeding rate, ABR) and joint bleeding rates (annualized joint bleeding rate, AJBR) in 2015 were 2 and 0 in children and 3 and 0 in adults, respectively. In 2015 only one child (1.2%) but 101 (53.2%) adults with severe haemophilia were anti-hepatitis C virus (anti-HCV) positive. The rate of anti-HCV positive patients with active hepatitis C dropped from 63.8% to 12.9%. CONCLUSIONS: Within the last decade more patients with severe haemophilia were switched to a prophylactic regimen going along with a moderate increase in factor consumption achieving a low ABR and AJBR.

A Novel ABO Gene Variant Leads to Discrepant Results in Forward/Reverse and Molecular Blood Grouping.

BACKGROUND: Discrepant results in antigen and reverse ABO blood typing are often caused by a variant ABO gene. Molecular analysis can help to characterize such variants. Here, we describe the identification of a novel ABO gene variant in a patient with aberrant ABO phenotype and discrepant genotyping results. METHODS: A patient with discrepant results in automated forward and reverse ABO phenotyping was further investigated by serological (gel and tube technique) and molecular (commercial and inhouse PCR-SSP, DNA sequencing) methods. A PCR-SSP system was established to screen the novel mutation in 1,820 blood donors. RESULTS: Standard serological tests confirmed blood group O, however, only anti-B isoagglutinins were present. A monoclonal anti-AB antibody detected very weak agglutination in gel technique. Standard ABO genotyping using PCR-SSP led to discrepant results (O(1)/O(1) or O(1)/A) depending on the test system used. ABO exon re-sequencing identified a novel missense mutation in exon 6 at position 248A>G (Asp83Gly) in the binding region of PCR-SSP primers for the detection of 261G alleles. Blood donors with regular ABO blood groups were all negative for the 248G allele designated Aw34. CONCLUSION: The novel ABO gene variant Aw34 is associated with very weak A antigen expression and absent anti-A isoagglutinins. The mutation is located in exon 6 close to the O(1)-specific 261G deletion in the binding region of PCR-SSP primers. Presumably, depending on the primer concentration used in commercial ABO genotyping kits, the mutation could lead to a false-negative reaction.