The classification is updated regularly, according to the classification

of the International Union of Immunological Societies (IUIS) [1] and progress in research. The technical structure of the ESID online database has been described in detail previously [17]. The database is used as a data collection platform by several national registries, including France, the Netherlands, Germany, Switzerland, Austria and the Czech Republic. In addition, data are imported on a regular basis from other national and local databases that operate separately. These include the national registries of Spain (REDIP; http://web.hsd.es/redip) and Italy (ipinet; http://www.aieop.org), and local hospital databases at University College London, selleck kinase inhibitor Newcastle General Hospital and University Medical Center Freiburg. Most of the participating centres are located in Europe, but there are also centres in Egypt. Dabrafenib concentration The complete list of documenting centres is available at http://www.esid.org/documenting-centers. Data are generally collected via electronic case report forms. The database has an inbuilt automatic quality assurance system, including field type,

range and plausibility checks. In addition, data sets are checked regularly for plausibility, completeness and double entries. As of 13 July 2011, a total of 13 708 patients had been registered in the ESID database. These had been entered by 102 documenting centres and national registries from 30 countries between 2004 and 2011. Some centres also diagnose or treat patients from abroad, so patients were from a total of 41 countries (including North Africa and the Middle East). The number of documented patients in relation to the total population varied considerably between countries.

In addition, the documentation in some countries is biased towards certain diseases because of centres specialized in a particular disease. This is, for example, the case in Hungary: of 367 reported cases, 130 (35·4%) were patients with hereditary angioedema, while the proportion of this GNA12 disease in the total study population is a mere 3·5%. In our analyses, we focused on eight countries (core countries) with a high documentation rate, a large number of reporting centres and a disease distribution that does not diverge strongly from the total distribution. These were France (3240), Spain (1662), Turkey (1486), United Kingdom (1148), Germany (1126), Italy (1083), Poland (508) and the Netherlands (433) (number of reported living patients given in brackets). Furthermore, we restricted some of our analyses to the most frequent diseases (core diseases).