The European internet-based patient and research database for primary immunodeficiencies: results 2006-2008

Abstract

Primary immunodeficiencies (PID) are rare diseases; therefore transnational studies are essential to maximize the scientific outcome and to improve diagnosis and therapy. In order to estimate the prevalence of PID in Europe as well as to establish and evaluate harmonized guidelines for the diagnosis and treatment of PID, the European Society for Immunodeficiencies (ESID) has developed an internet-based database for clinical and research data on patients with PID. This database is a platform for epidemiological analyses as well as the development of new diagnostic and therapeutic strategies and the identification of novel disease-associated genes. Within 4 years, 7430 patients from 39 countries have been documented in the ESID database. Common variable immunodeficiency (CVID) represents the most common entity, with 1540 patients or 20.7% of all entries, followed by isolated immunoglobulin (Ig)G subclass deficiency (546 patients, 7.4%). Evaluations show that the average life expectancy for PID patients varies from 1 to 49 years (median), depending on the type of PID. The prevalence and incidence of PID remains a key question to be answered. As the registration progress is far from finished we can only calculate minimum values for PID, with e.g. France currently showing a minimum prevalence of 3.72 patients per 100,000 inhabitants. The most frequently documented permanent treatment is immunoglobulin replacement; 2819 patients (42% of all patients alive) currently receive this form of treatment.

Fig. 1

Minimum incidence of primary immunodeficiency (PID) cases in 100 000 live births, grouped in 4-year periods, and distribution in main PID categories. (a) France: n (1995–2006) = 1110, demographics: INSEE (http://www.insee.fr); (b) United Kingdom, n (1995–2006) = 288, demographics: UK Office for National Statistics (http://www.statistics.gov.uk).

Fig. 2

Age at death of patients from selected subcategories and diseases. Box and whisker chart with whiskers representing the maximum and minimum values; the box represents the upper and lower quartile, the white line represents the median. The number of evaluated patients is given in brackets.

Fig. 3

Shares of intravenous immunoglobulin (IVIG) and subcutaneous immunoglobulin (SCIG) replacement in selected European countries as documented in the European Society for Immunodeficiencies (ESID) database. The total number of documented patients receiving immunoglobulin replacement in each country is given in brackets.

Fig. 4

Mean interval of intravenous immunoglobulin (IVIG) replacement by countries as documented in the European Society for Immunodeficiencies (ESID) database. The total number of patients currently treated with IVIG for whom the interval has been documented is given in brackets. Only countries with 10 or more cases containing data on intervals are displayed.