Health condition
Specific antibody deficiency
Specific antibody deficiency is the immune failure that hides behind normal results: total immunoglobulins and subclasses are fine, but the system cannot mount protective responses to polysaccharide vaccines - found only by deliberately testing vaccine responses.
Why trust this guide
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Editorial team
Written by our editorial team from the UK sources listed on each page.
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Sourced from guidance
Checked against current NHS and UK specialist society guidance at the time of review.
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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.
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Definition: recurrent bacterial infections with normal IgG, IgA, IgM and subclasses, but inadequate response to pneumococcal polysaccharide vaccination
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The test sequence: baseline pneumococcal serotype antibodies, vaccinate (Pneumovax), re-measure at 4-6 weeks - protective responses across serotypes are what count
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Typical picture: adults or children with sinusitis, otitis and chest infections whose standard immune screens keep coming back 'normal'
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Management mirrors severity: conjugate pneumococcal vaccines (which recruit T-cell help), prophylactic antibiotics, and immunoglobulin replacement for the most affected
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Definitions vary between guidelines - interpretation belongs with a clinical immunologist
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
Polysaccharide capsules are the armour of the bacteria that cause most sinus and lung infections, and answering them is a specialised skill the immune system performs without T-cell help. Some people simply cannot do it - their antibody factories work for everything else, so every routine test looks normal, and years pass with the patient told their immunity is fine while the infections continue. The deficiency is invisible until someone issues the specific challenge: vaccinate against pneumococcus and measure whether protection actually appears.
Diagnosis and treatment routes
The workaround exploits immunological engineering: conjugate vaccines wire the polysaccharide to a protein, recruiting T-cell help and often achieving responses the plain vaccine could not - both a treatment and further diagnostic information. Beyond vaccination, care is tiered from prompt standby antibiotics through winter prophylaxis to immunoglobulin replacement for those still suffering breakthrough infections or accruing lung damage. If your infections are real but your tests are 'normal', vaccine-response testing is the missing step; a private immunologist can typically arrange it 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 Specific antibody deficiency.
Quick, plain-English answers to what people ask us most.
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Can you explain what specific antibody deficiency is?
Specific antibody deficiency is a medical condition that can affect people differently depending on severity, underlying cause and overall health. A clinician can confirm the diagnosis and explain what it means specifically for you.
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What causes specific antibody deficiency?
Causes vary and can include genetic, environmental, lifestyle and other health-related factors, and in some people no single clear cause is found. Your clinician can help identify anything relevant to your own case.
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What does specific antibody deficiency look like or feel like?
Symptoms vary between individuals and depend on which body systems are affected and how significant the underlying problem is. Keeping track of what you notice, and when, helps your clinician assess it accurately.
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How worried should I be about specific antibody deficiency?
Severity varies from mild and self-limiting to more significant, depending on the underlying cause and how it's managed. A clinical assessment is the best way to understand what it means in your specific situation.
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Is specific antibody deficiency hereditary or genetic?
This depends on the specific condition — some cases have a genetic or familial component, while others are linked more to environmental, lifestyle or other health factors. If you have a relevant family history, it's worth mentioning to your clinician.
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Is there a cure for specific antibody deficiency?
Many cases can be effectively treated or managed, and prevention strategies exist for some causes, though this depends on the specific underlying reason in your case. Your clinician can explain what's realistic for you.
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How is specific antibody deficiency treated?
Treatment is tailored to the underlying cause and severity, and can range from simple lifestyle or self-management measures to medical or specialist intervention.
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What is the long-term outlook for specific antibody deficiency?
This varies depending on the underlying cause, how early it's identified, and how well it responds to treatment — your clinician can give a more specific expectation once assessed.
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When should specialist referral be considered for specific antibody deficiency?
Specialist referral is worth considering if symptoms persist, are getting worse, or aren't responding to initial treatment — your GP can help decide the right pathway and urgency.
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When should I see a doctor about specific antibody deficiency, and how quickly can I be seen privately?
See a doctor if symptoms are persistent, worsening, or affecting your daily life — earlier assessment generally leads to better management. NHS routine referrals for this kind of concern often take 20–45 weeks or longer depending on the area, while a private consultant can typically see you within about 2 weeks, with faster access to scans and specialist opinion.