Could a simple blood test unlock the mystery of your recurring infections?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * 18 to 65 year old patients * With a history of recurrent bacterial infections of upper and/or lower respiratory tract for at least 2 years, and fulfilling the specific following criteria: * Recurrent benign infections currently requiring 6 courses of antibiotics /year or more, or Bilateral bronchiectasis/bronchiolitis (after exclusion of cystic fibrosis and ciliary dyskinesia) AND recurrent benign infections currently requiring 3 courses of antibiotics /year or more or A history of severe upper/lower respiratory tract bacterial infection, and/or invasive infection with Streptococcus pneumonia, Streptococcus pyogenes or Haemophilus influenzae, which required hospitalization in the last 2 years, AND recurrent benign infections currently requiring 3 courses of antibiotics /year. * Normal serum IgG, IgA, IgM and IgG subclasses levels, normal CH50 and serum complement C3 and C4 proteins levels, normal T cells count * Normal B cell count, normal serum protein electrophoresis and immunofixation. (\* excepted for Pseudomonas aeruginosa colonization) Exclusion Criteria: * Any general condition that predisposes to infections: solid or hematological malignancies, diabetes mellitus, severe alcohol or intravenous drug abuse, chronic liver or kidney failure, human immunodeficiency virus infection, anatomic or functional asplenia, drug-induced 1 neutropenia, or solid organ or hematopoietic stem cell transplantation; * Any local predisposing factor to infections: cigarette smoking (\> 10 pack-year and/or 5 cigarettes/day), underlying infection (tuberculosis, influenza…), chronic obstructive pulmonary disease, oral, dental or skin conditions favorizing infections, streptococcal skin infections * Any other SID or PID diagnosed before inclusion * Pregnancy * PPV23 administration in the last 2 years (risk of hyporesponsiveness)