From infections to autoimmunity: Diagnostic challenges in common variable immunodeficiency

Core Tip

Core Tip: Common variable immunodeficiency has to be considered in adults with recurrent respiratory tract infections, bronchiectasis, cytopenia, generalized lymphadenopathy, sarcoid-like symptoms, colitis in whom other conditions were excluded. Low calculated globulin, which is the difference between total protein and albumin levels, suggests hypogammaglobulinemia. Patient with common variable immunodeficiency are referred for commencing replacement immunoglobulin therapy, which should be continued regularly throughout life. It can be administered intravenously, subcutaneously and via the hyaluronidase-facilitated subcutaneous route. One must bear in mind that in patients with hypogammaglo-bulinemia and those treated with polyclonal immunoglobulin G products, serological tests based on determination of antibodies are unreliable.