There were major differences between the responses of these two groups and those of the general AAAAI respondents whose GSI-IX clinical practice was composed of < 10% of PID patients.

These differences included the routine use of intravenous immunoglobulin therapy (IVIg) for particular types of PIDs, initial levels of IVIg doses, dosing intervals, routine use of prophylactic antibiotics, perceptions of the usefulness of subcutaneous immunoglobulin therapy (SCIg) and of the risk to patients’ health of policies adopted by health-care funders. Differences in practice were identified and are discussed in terms of methods of health-care provision, which suggest future studies for ensuring continuation of appropriate levels of immunoglobulin replacement therapies. Primary immunodeficiency diseases (PIDs) comprise Neratinib mouse a group of more than 150 distinct diseases arising from 120 different genetic abnormalities that affect development and/or function of the immune system [1]. Despite the heterogeneity of PIDs, impairment of immunity results in the common hallmark of susceptibility to infection. While once thought to be exceedingly rare, symptomatic primary immunodeficiencies are now appreciated to range from 1:500–1:500 000

in the general population in the United States and Europe [2,3]. A random digit dialling telephone survey in 2007 estimated that one in 1200 people within the United States are diagnosed with an immunodeficiency [4], old although this included selective immunoglobulin

A deficiency (IgAD), which is not usually clinically significant. These diseases have been considered rare, thus controlled studies investigating clinical interventions are scarce. In an effort to address these issues, several regions have created national registries for PIDs to enable epidemiological studies. In the absence of controlled studies of therapeutic interventions for patients with PIDs, efforts have been organized to describe expert practice in order to ascertain consistencies, differences and outstanding questions. In the United States a recent survey of expert practice has been performed of the members of the American Academy of Allergy, Asthma and Immunology (AAAAI) [5]. In the majority of centres in the United States, immunology is a subspeciality with combined training in allergy and certifying examinations covering both clinical disciplines. In Europe, clinical immunology is sometimes, although not always, a distinct and separate subspeciality; in many other countries, PID patients are managed by physicians or paediatricians working in related specialities. With this difference in mind, we sought to compare the expert practice of PID between members of the European Society for Immunodeficiencies (ESID) and the AAAAI.