The Infection in Immunocompromised Pediatric Patients group and the Immunology group at Vall d’Hebron Institute of Research (VHIR) have started to collect blood samples from patients with primary immune deficiencies and their relatives who also participated in the "http://www.vhir.org/serveis/BIOBANC/presentacioserveisinfor.asp?Idioma=en&mv1=3&mv2=8&mh1=3&mh2=8&mh3=4&mh4=0&ms=0&plataforma=5&servei=1" Immunology Bank of the HUVH Biobank. The aim of the groups is to become the biobank of reference in these diseases in Catalonia.VHIR researchers will collect samples of the 3 types of patients that they treat in the Pediatric Infectious Diseases and Immunodeficiencies Unit (UPIIP): patients with a clinically compatible case and genetic confirmation, patients with primary immunodeficiencies in which the gene that causes the disease is still unknown, and patients with an unknown type of immunodeficiency. All the samples will be collected during routine blood tests, and with parental consent. In this case, researchers will also offer to the patients’ relatives the opportunity of being studied in order to carry out genetic studies with more diagnostic ability.With the samples collected in a standardized model, researchers will investigate these diseases, optimize the diagnosis and offer genetic counseling to the closest relatives, in collaboration with the Clinical Genetics Area at Vall d’Hebron hospital. This project has the support of the Catalan association of patients with immunodeficiencies "http://www.acadip.org/ca.html" (ACADIP), the BCN-PID Foundation and the fundraising campaign "http://www.totsambdidac.com/" "tots amb Didac", that has raised over 43,000 euros for the research at VHIR in these rare diseases.Primary Immunodecifiencies at Vall d'HebronThe UPIIP is the leading unit in Spain in the field of primary immune deficiencies: it has nearly 500 pediatric patients diagnosed, and "http://www.vhebron.net/ca/web/intranet-vall-d-hebron/actualidades/-/asset_publisher/jgfOy6A55Af2/content/vall-d-hebron-unic-centre-a-catalunya-acreditat-per-formar-especialistes-en-immunodeficiencies-primaries/10165?redirect=http%3A%2F%2Fwww.vhebron.net%2Fca%2Fweb%2Fintranet-vall-d-hebron%2Factualidades%3Fp_p_id%3D101_INSTANCE_jgfOy6A55Af2%26p_p_lifecycle%3D0%26p_p_state%3Dnormal%26p_p_mode%3Dview%26p_p_col_id%3Dcolumn-2%26p_p_col_pos%3D1%26p_p_col_count%3D3" it has recently been recognized Centre for Fellowships of "http://esid.org/" the European Society of Immunodeficiencies (ESID). The Immunology Service is continuously updating and improving the techniques for the identification and characterization of mutations in patients with primary immunodeficiencies. The members of the group are also developing several research projects related to this field and are members of the "http://www.focisnet.org/" Federation of Clinical Immunology Societies (FOCIS).Primary immune deficiencies are a group of rare diseases caused by alterations in the immune system of children, which globally affect 1 out of 2,000 newborns. Patients are susceptible to suffer infections that, if not treated properly, can be lethal or leave sequels that would worsen their quality of life.