Common variable immunodeficiency

Last revised by Yuranga Weerakkody on 18 Apr 2021

Common variable immunodeficiency (CVID) is a condition that is associated with an impaired immune system. It is considered the most common symptomatic primary immunodeficiency and is characterized by recurrent respiratory tract infections.

Clinical presentation

The commonest presentation is that of frequent respiratory tract infections.


The exact cause is unknown in at least 90% of cases, while a genetic cause may be present in <10% of cases. The conditions involve:

  • low levels of most or all of the immunoglobulin (Ig) classes - hypogammaglobulinaemia
  • lack of B lymphocytes or plasma cells that are capable of producing antibodies
  • frequent bacterial infections

The following serological abnormalities may be present:

  • serum IgA and IgG: decreased but not absent
  • serum IgM: occasionally decreased
  • circulating T and B lymphocytes: present

It can affect multiple organ systems:

ADVERTISEMENT: Supporters see fewer/no ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.