Faculty Collaboration Database

The Malmö International Brother Study (MIBS): further support for genetic predisposition to inhibitor development in hemophilia patients. Haemophilia 2001 May;7(3):267-72

Date

05/31/2001

Pubmed ID

11380630

DOI

10.1046/j.1365-2516.2001.00510.x

Scopus ID

2-s2.0-6644227418 (requires institutional sign-in at Scopus site)   178 Citations

Abstract

The issue of factors predisposing for inhibitor development in haemophilia patients is still largely unresolved. In an attempt to address this problem, we initiated a registry in 1996 of siblings with haemophilia and with or without a history of inhibitors. Four hundred and sixty families have accrued, of whom 388 suffer from haemophilia A and 72 haemophilia B. Twenty-five of the brother pairs are twins. The inhibitor incidence in all families with severe haemophilia A was 31.7%. The corresponding figure in the caucasian patients was 27.4%, whereas a higher incidence of inhibitors was reported in the black subjects (55.6%). Twins were reported in six of the 100 inhibitor families, for whom monozygocity was confirmed in three cases. In 32 families (32%), at least two brothers had a history of inhibitors. In 22 (69%) of these families, the inhibitor was also of the same type, i.e. either high- or low-responding. The overall concordance within the severe haemophilia A families was found to be 78.3% (195/249) compared to an expected figure of 68.0% and 58.0% using an inhibitor incidence of 20 and 30%, respectively (P < 0.0001). The corresponding figure for the twins was 88.2% (15/17). Moreover, the risk for inhibitor development in families with a previous inhibitor history was found to be 48% (95% confidence interval [CI] 35-62%), whereas the risk in families with no previous known inhibitor was only 15% (95% CI 11-21%) corresponding to a relative risk of 3.2 (95% CI 2.1-4.9). Immune-tolerance induction was reported in 24 families, of whom 13 siblings were successfully treated. Our data clearly support the concept that a genetic predisposition for inhibitor development exists. However, the markers of this predisposition remain to be elucidated and we believe that the MIBS registry will be useful for this purpose.

Author List

Astermark J, Berntorp E, White GC, Kroner BL, MIBS Study Group

Author

Gilbert C. White MD Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Chi-Square Distribution
Factor VIII
Family Health
Genetic Predisposition to Disease
Hemophilia A
Hemophilia B
Humans
Isoantibodies
Male
Nuclear Family
Registries