Primary Immunodeficiency (PID)

  • Known primary humoral (antibody), cell mediated and innate immune defects


  • Adults or children with unusually frequent or severe infections, or infections with unusual organisms. Secondary causes should be excluded (eg drugs, underlying malignancy, structural defects)


  • Additional information required: Results of microbiology (eg sputum/swabs), full immunisation history (vaccine names and date administered). Radiology (if done outside Derriford). Details of family history (especially infections)


  • If history strongly suggestive of immunodeficiency referral should not be delayed pending blood results, however useful investigations include FBC with differential, immunoglobulin levels (if recurrent bacterial infections), sputum cultures.


  • If history suggestive of hereditary angioedema (angioedema, no urticaria, often involving recurrent abdominal pain, family history) check C4 and if low referral to PID clinic. If strongly suggestive history and normal C4, referral to PID clinic appropriate.  Otherwise treat as for spontaneous angioedema.


Review Date                      13/8/2019

Next Review Date           13/8/2020

Author                                  Dr Andrew Whyte, Consultant Allergist and Immunologist, Derriford Hospital

GP Sifter                              Dr Isabel Boyd


Version No.                        1.1