Health condition
NFKB1 and NFKB2 deficiency
Variants in NFKB1 - now recognised as one of the commonest genetic causes of CVID - and in NFKB2 disrupt a master switch of immune gene expression, producing antibody deficiency with autoimmunity; NFKB2 disease adds a distinctive endocrine twist, pituitary failure.
Why trust this guide
- 01
Editorial team
Written by our editorial team from the UK sources listed on each page.
- 02
Sourced from guidance
Checked against current NHS and UK specialist society guidance at the time of review.
- 03
Current for 2026
Reviewed on 2026-09-27 with the next review scheduled for 2027-09-27.
Key facts
The essentials at a glance.
The symptoms to recognise, when to seek help, which specialist to see, and what treatment usually involves.
-
NFKB1 haploinsufficiency underlies a meaningful share of 'CVID': recurrent respiratory infections, low immunoglobulins, autoimmunity, gut disease and lymphoproliferation, often worsening with age
-
Penetrance is strikingly variable - a well parent can carry the same variant as a severely affected child
-
NFKB2 disease pairs antibody deficiency with ACTH deficiency and other pituitary hormone failure (the DAVID syndrome pattern) plus skin, nail and hair changes in some
-
A 9am cortisol belongs in the workup of NFKB2 families - unrecognised adrenal insufficiency is dangerous
-
Management builds on CVID care - immunoglobulin replacement, infection and complication surveillance - with endocrine replacement where the pituitary is involved
Understanding the condition
What it is and what happens next.
What causes it, how it is diagnosed, and the treatment routes available in the UK.
What it is and how it feels
NF-kappa-B is the transcription switchboard through which immune receptors order their responses; halve the dose of its components and antibody production, B-cell survival and immune regulation all wobble. NFKB1 families illustrate genetics' loose grip on destiny - across one pedigree the same variant may produce severe CVID with autoimmune cytopenias in one member, mild sinus infections in another, and nothing yet in a third - which is why cascade testing pairs with monitoring rather than alarm. NFKB2 adds a lesson in unexpected anatomy: the same pathway builds the pituitary's ACTH axis, so immunodeficiency arrives with creeping cortisol failure.
Diagnosis and treatment routes
For patients already carrying a CVID label, genetic testing increasingly changes real decisions - anticipating complications, guiding family advice, and flagging the endocrine checks that NFKB2 makes mandatory: cortisol, thyroid and growth axes reviewed at diagnosis and over time, since deficiency can develop late. Core care remains immunoglobulin replacement, vaccination strategy and structured surveillance of lungs, gut, blood counts and lymphoid tissue. If your CVID has never been genetically characterised, or antibody failure travels with unexplained fatigue suggesting cortisol deficiency, seek specialist review - privately, typically within about two weeks.
Seeing a specialist
Who to see, and how quickly you can be seen.
The specialist for this condition is usually a consultant clinical immunologist. Your GP can refer you on the NHS, or you can arrange a private consultation directly.
A quiet reminder
This guide is for information, not medical advice.
Your GP knows your history and can tell you which parts apply to you. If in doubt, see them - and seek urgent care for any of the emergency symptoms described above.
Frequently asked
Common questions about NFKB1 and NFKB2 deficiency.
Quick, plain-English answers to what people ask us most.
-
What is NFKB1 and NFKB2 deficiency?
NFKB1 and NFKB2 deficiency are rare inherited immune disorders causing a form of common variable immunodeficiency, in which the body cannot produce adequate antibodies, leading to recurrent infections.
-
What causes NFKB1 and NFKB2 deficiency?
These conditions are caused by mutations in the NFKB1 or NFKB2 genes, which play important roles in normal immune system signalling, typically inherited in an autosomal dominant pattern.
-
What are the symptoms of NFKB1 and NFKB2 deficiency?
Symptoms include recurrent bacterial infections, particularly affecting the respiratory tract, and in some people, autoimmune complications or specific patterns of low blood cell counts.
-
Is NFKB1 and NFKB2 deficiency hereditary?
Yes, these conditions are inherited in an autosomal dominant pattern, though severity can vary considerably even within the same family carrying the identical mutation.
-
Is NFKB1 and NFKB2 deficiency dangerous?
Yes, recurrent infections can cause significant illness and, over time, lasting organ damage such as chronic lung disease if not adequately treated, making regular immunology follow-up important.
-
How is NFKB1 and NFKB2 deficiency treated?
Treatment typically includes regular immunoglobulin replacement therapy to boost antibody levels, alongside prompt treatment of infections and monitoring for associated autoimmune or blood complications.
-
When should I see an immunologist about suspected NFKB1 or NFKB2 deficiency, and how quickly can I be seen privately?
See an immunologist for recurrent infections, particularly with a family history of immune problems. A private immunologist can typically arrange assessment and testing within about two weeks.