Immunology - Specific Antibody Deficiency

What is Specific Antibody Deficiency (SAD)?

Specific Antibody Deficiency (SAD) means your antibodies against certain germs (pathogens) like pneumococcus are low, so you are more susceptible to infections caused by these bacteria and similar bacteria (Moraxella and Haemophilus).

Streptococcus Pneumoniae also known as pneumococcus (pronounced..new..mo..coc..us) is a bacterium that is sometimes found in the nose and throats of healthy people and is spread from person to person through close contact.

Pneumococcus can cause sinus and ear infections, chest infections pneumonia, meningitis and infections in the blood stream.

How is the diagnosis of SAD made?

You were originally referred to the Immunology department because of repeated infections or because you were found to have low antibody levels after receiving the pneumonia jab (vaccine).

Along with other Immunology blood tests, the Immunology team tested your functional antibodies (specific antibodies) against certain pathogens/germs.

You may need to receive other vaccines. Further blood tests are taken post immunisation to see if your antibodies levels have improved.

Your Pneumococcal antibody levels were still low after the vaccination, this means you have Specific Antibody Deficiency.

What is the treatment for SAD?

Treatment depends on your symptoms, number and severity of infections and your antibody levels to pneumococcus. Some patients need additional vaccinations and treatment of infections as and when they occur.

Prophylactic antibiotics may be used, which means taking antibiotics regularly and not just for a treatment of infection if you have frequent infections related to this subtle immune problem.

A minority of patients with low levels of antibodies (not showing response to vaccination) who have frequent or severe infections may require further treatment called immunoglobulin replacement therapy.

This is considered only if the chest infections are thought to be relevant to the underlying immune problem and the prophylactic antibiotic have not prevented the infections.

What happens if I become unwell and get an infection?

Although you are on antibiotics to help prevent infections, there is still a chance that you will get infections. If an infection does occur, please see your GP for further antibiotic treatment specific to that infection.

You should give a sputum sample to your doctor to make sure you are on the right antibiotics.

Use the antibiotic guidelines given to you by the Immunology team. Your GP should have a copy of these guidelines.

Whilst on these antibiotics, stop your prophylactic antibiotic and recommence when you finish the course.

Is it ok for me to stay on long term antibiotics?

Antibiotic prophylaxis is only considered if you have frequent chest infections thought to be related to your underlying immune problem.

If you start to feel unwell on the antibiotics, please contact your GP or the immunology team.

Potentially there are concerns about the development of antibiotic resistant bacteria.

Are there any side effects or risk to having antibiotics?

Antibiotics do have side effects, but these can differ from person to person. Some people can have no side effects at all, others, mild side effects and some rarely can have full allergic reactions.

Side effects can include diarrhoea, nausea, rashes (urticaria) or a rash with sun exposure with Doxycycline.

Less often: fever, vomiting, dermatitis and angioedema (swelling). Some patients can develop liver abnormalities. Irregular heart rate (Azithromycin) and deafness (Azithromycin).

Risks can include developing candidiasis (thrush) or having an allergic reaction, which can cause anaphylaxis. Doctors will discuss any known allergies with patients first and prescribe the most appropriate antibiotics.

What can be done to prevent and monitor side effects?

You remain under regular review by the Immunology team.

We usually recommend having an Electrocardiogram (ECG - Tracing of the heart) before and 2 weeks after commencing on Azithromycin.

Good sun protection is advised while taking Doxycycline. We recommend having regular blood tests for monitoring the liver whilst taking Doxycycline and Azithromycin.

How will I know if my antibody levels change?

Patients will stay under the care of the Immunology team and will be seen for review by the Immunology Consultant or Immunology Trainee and specialist nurses and clinical nurse specialists.

The review will be mainly focused on how you have been over the previous months with regard to infections, days off work, hospital admissions and review of medications.

A blood test will be taken to monitor your levels of antibodies. If there are any changes in the blood test results or in your condition, then possible changes in the treatment and further management will be discussed with you.

Will I have to change my lifestyle?

There are no major changes to your life apart from taking regular antibiotics and being more aware of how/when to treat any infections and taking care of yourself.

The immunology nurse specialists will give advice of healthy lifestyles including diet, exercise and staying well.

Referral to physiotherapy can be made to help if you have problems expectorating sputum.

Is there anywhere else I can go to get further information about SAD?

For more practical help e.g. insurance and employment rights you can visit:

UK PIPS - http://www.ukpips.org.uk/

Immunodeficiency UK - www.immunodeficiencyuk.org

You are able to download leaflets from these websites.
 
If you require further information or wish to discuss any issues with the immunology specialist nurses please contact the immunology team:

Immunology Department
Division of Surgery & Tertiary Medicine
Salford Royal Hospital
Northern Care Alliance NHS Group
2nd Floor, Turnberg Building, Stott Lane,
Salford, M6 8HD
Tel: 0161 206 0522 - Secretaries
Tel: 0161 206 5576 - Immunology Specialist Nurses Salfordimmunology.nurses@nca.nhs.uk