Epidermolysis Bullosa Registries and the Epidemiology of Epidermolysis Bullosa (EB)

Abstract

Meaningful basic and clinical research is heavily dependent on the availability of large numbers of well-characterized patients, not only for participation in randomized clinical trials but also as a source of tissue samples (blood, DNA, others), the latter of which may be used experimentally to gain further insight into the pathogenesis of the disease in question. This is particularly critical for rare diseases having multiple phenotypes and genotypes, since far too few patients may be identified by any single investigator or within any one institution to permit the proper pursuit of such studies. Disease registries, if properly designed and executed, can overcome this hurdle, especially if population based. Inherited epidermolysis bullosa (EB) serves as the model for such an approach, based on the robust experiences of the National (USA) EB Registry (NEBR) and several smaller EB registries that have subsequently arisen in other countries. A properly designed rare disease registry can serve as far more than just a repository of patients for later clinical study. As well demonstrated by 16 years of continuous data collection by the NEBR, rigorous methodological application of the principles of epidemiological case finding and biostatistical analysis and modeling can permit the determination of not only the prevalence and incidence of each disease subtype but also the characterization of the protean clinical and laboratory findings present in each. As a correlate, longitudinal data collection can lead to accurate prognostication of the natural history of the disease. In this chapter we will discuss in detail the optimal design of rare disease registries, as well as the potential pitfalls and limitations associated with poor study design, and then illustrate these by using the extensive data generated by the NEBR and other EB registries worldwide.