Category: Immune Disorders

Allergic reactions occur when the immune system responds to a substance that is usually harmless. Allergies can involve foods, medicines, insect stings, pollen, animals and many other triggers.

Common symptoms

Symptoms may include sneezing, itchy or watery eyes, hives, swelling, gastrointestinal symptoms or wheezing. The pattern depends on the trigger and individual response.

Severe reactions

A severe allergic reaction can involve breathing difficulty, throat or tongue swelling, collapse or rapidly developing symptoms affecting more than one body system. Emergency treatment is required.

Know your plan

People known to be at risk may be prescribed emergency medication and given an action plan. They and those close to them should understand that plan.

Testing needs context

Allergy tests should be interpreted alongside a clinical history. A positive test does not always mean that exposure will cause clinically important symptoms.

Avoid unnecessary restriction

Eliminating many foods without a clear diagnosis can create nutritional problems. Professional assessment can help distinguish allergy from intolerance and other causes.

A severe allergic reaction with breathing difficulty or collapse requires emergency medical assistance.

Anaphylaxis: act immediately

If anaphylaxis is suspected, use the person’s prescribed adrenaline auto-injector immediately according to its instructions and call emergency services. In South Africa call 112 from a cellphone or 10177 for an ambulance. Lie the person down; if breathing is difficult, allow the shoulders to be raised or a slow supported sitting position. Do not let them stand or walk. During pregnancy, lying on the left side is advised. If symptoms persist after five minutes, use a second auto-injector if available, following the emergency plan. Emergency assessment is needed even if the person improves.

Antihistamines do not replace adrenaline for anaphylaxis. A severe reaction can occur without obvious hives.

Practical appointment checklist

1. Learn the prescribed device technique before an emergency.
2. Check expiry dates and carry the prescribed devices.
3. Share the action plan with family, school or work where appropriate.
4. Record suspected triggers and the sequence of symptoms.
5. Arrange allergy follow-up after a serious reaction.

Common question

Does a positive allergy test mean I must avoid that food?

Not necessarily. Results must be interpreted with symptoms and exposure history by an appropriate clinician.

Sources and further reading

• NHS: anaphylaxis first aid

Related support

Use our appointment preparation guide, resources and community support to plan your next step.

Sources checked 22 September 2026. General education, not individual medical advice. International service arrangements may differ from South Africa. Featured artwork is illustrative, not a patient testimonial.

A low IgA result can be confusing, especially if it is discovered while investigating another problem. Some people have few or no symptoms; others need care for recurrent infections or associated conditions. The result needs an explanation in the context of your health.

What is IgA?

Immunoglobulin A, or IgA, is an antibody involved in protecting mucosal surfaces, including the respiratory and digestive tracts. Selective IgA deficiency describes very low or undetectable IgA with normal levels of the other main antibody classes, IgG and IgM, in someone aged four or older.

This does not mean the entire immune system is absent. Many people have no symptoms, while others experience infections, allergies or autoimmune conditions. The Immune Deficiency Foundation’s IgA deficiency guide explains the diagnosis.

A laboratory number is only part of the story

A clinician considers your age, infection history, medicines and other test results. Some people are identified during assessment for conditions such as coeliac disease. Ask what the finding means for the investigation already under way and whether further tests are needed.

Bring the original report rather than relying on a remembered number. Laboratories use different units and reference ranges. It is reasonable to ask the clinician to explain the result in ordinary language and write down the follow-up plan.

Treatment is directed at the problems you actually have

People without symptoms may not need specific treatment. If infections occur, treatment depends on the infection and the wider clinical picture. Some people with recurrent infections need a prevention plan. Associated allergic or autoimmune conditions require their own care.

Selective IgA deficiency is not managed automatically with the same antibody-replacement treatment used for CVID. Do not assume that an infusion described online is something you need. MedlinePlus explains selective IgA deficiency and its management.

Tell the team before a blood transfusion

People with IgA deficiency should tell healthcare professionals about the diagnosis, particularly before receiving blood products, and report any previous transfusion reaction. Serious reactions are rare, but the transfusion team may need to take precautions. Ask your clinician what information you should carry. Do not refuse or delay emergency care while trying to resolve this online.

Questions worth asking at your next visit

• Does this result meet the criteria for selective IgA deficiency, or is further assessment needed?
• Which of my symptoms might be related, and which need separate investigation?
• When should I contact you about a possible infection?
• What should I tell other clinicians or a transfusion team?
• Do I need follow-up tests, and who will arrange them?
• What vaccination advice applies to my circumstances?

The IDF vaccine guide explains why recommendations depend on the particular immune problem and treatment. Avoid applying a blanket “no vaccines” rule to yourself.

Keep useful information in one place

A short folder can hold your diagnosis letter, recent results, medicine list and contact details. If you have repeated infections, record the dates, sites, treatment and recovery. Ask how your team wants you to share that information.

Follow your personal illness plan and seek urgent help when seriously unwell. Severe breathing difficulty or collapse requires emergency assistance. For broader context, see our immune-deficiency introduction. Our guide to explaining support needs offers practical language for conversations with family or work.

General health information, not an individual diagnosis or treatment plan. Sources checked on 16 September 2026. International sources may describe services or medicines that differ from those available in South Africa. The featured image is illustrative.

A practical record for follow-up

1. Record significant infections, treatments and recovery dates.
2. Bring your antibody results and vaccination history to the next review.
3. Tell healthcare staff about the diagnosis before a transfusion or new treatment.
4. Ask which symptoms should prompt contact and who will review recurring infections.

Keep a copy

Save the agreed plan and review date with your appointment notes. Our resources can help you find further information.

Repeated infections can disrupt work, study and family life long before there is a clear explanation. Common variable immune deficiency, or CVID, is one possible diagnosis. It requires specialist assessment; repeated colds alone do not establish it.

What does CVID mean?

CVID is an antibody deficiency with a variable pattern of symptoms. People may have repeated sinus, ear or lung infections, and some experience digestive, inflammatory or autoimmune problems. It may be diagnosed in childhood or adulthood.

The word “common” is part of the condition’s name; it does not mean that most people with frequent infections have CVID. See the American Academy of Allergy, Asthma & Immunology’s CVID guide for an introduction.

Diagnosis needs more than one result

Assessment considers the history of illness, levels of immunoglobulins and how effectively the body makes specific antibodies. Specialists also consider other reasons for low antibody levels. A single result on its own should not be used to label someone with CVID.

The Immune Deficiency Foundation’s CVID guide explains the diagnosis and continuing care. Ask which criteria apply in your case and whether further testing is needed before treatment begins.

Why immunoglobulin replacement may be used

Immunoglobulin replacement supplies antibodies to help protect against infections. It is an important treatment for many people with CVID, but it does not mean every symptom or complication disappears.

It can be given into a vein (IVIG) or under the skin (SCIG). The route, schedule, supervision and training should be chosen with the prescribing team. Do not change doses or infusion methods based on another person’s experience. IDF’s immunoglobulin replacement guide explains the options.

Follow-up goes beyond antibody levels

Some people need treatment for infections or additional problems involving the lungs, gut or immune regulation. Regular review helps the team respond to changes. Report persistent new symptoms, problems with treatment or difficulties obtaining prescribed supplies.

Ask what monitoring you need and how success will be judged. Fewer infections, recovery time and how you are managing everyday life are useful topics for that conversation. The plan should be specific to you, not copied from a social-media group.

Make treatment fit real life

Before starting or changing a treatment arrangement, discuss practical details:

1. Access: where treatment happens, referral requirements and likely costs.
2. Time: travel, time away from work and who can help with responsibilities.
3. Training: who teaches you what to do and where written instructions are kept.
4. Problems: whom to contact about side effects, equipment or a missed appointment.
5. Continuity: what happens during travel, a move or an interruption in supply.

You do not have to solve these issues alone. Tell the team early if the arrangement is becoming unmanageable rather than quietly missing treatment.

Keep a clear illness plan

Ask your specialist which infection symptoms need same-day advice and when emergency assessment is needed. Seek emergency help for severe breathing difficulty, collapse or new confusion. Do not wait for a routine review if you are seriously unwell.

Vaccination decisions should be discussed with your immunology team, taking treatment into account. The IDF vaccine guide provides background. For the wider picture, read Understanding Immune Deficiencies and our shared caregiving plan.

General health information, not an individual diagnosis or treatment plan. Sources checked on 16 September 2026. International sources may describe services or medicines that differ from those available in South Africa. The featured image is illustrative.

“A weak immune system” can mean many different things. It does not tell you which part of the immune system is affected, how serious the problem is or what care is appropriate. A useful explanation starts with a specific diagnosis.

Primary and secondary describe the cause

Primary immunodeficiencies, also called inborn errors of immunity, arise from problems intrinsic to the immune system. Some are recognised in childhood; others are diagnosed later. Secondary immunodeficiencies develop because of another condition or treatment, such as certain infections or immune-suppressing medicines.

The distinction does not rank severity. “Secondary” does not mean minor, and “primary” does not mean that everybody has the same risks. The Immune Deficiency Foundation’s terminology guide explains these terms.

Immune deficiency is different from autoimmunity

Immune deficiency involves inadequate immune protection. Autoimmunity involves an immune response directed against the body’s own tissues. They are different concepts, although some people experience both. An autoimmune diagnosis should not automatically be relabelled as immune deficiency.

The immune system has several interacting parts, including antibodies and different cells. Different disorders affect different functions. Read IDF’s explanation of how the immune system works for background.

There is more than one antibody deficiency

CVID and selective IgA deficiency are examples of distinct diagnoses, not interchangeable labels. Other conditions can affect different antibodies, immune cells or defence pathways. Treatment that helps one person may not be needed or suitable for another.

Our separate guides explain common variable immune deficiency (CVID) and selective IgA deficiency. Use them to prepare questions, not to assign yourself a diagnosis from symptoms or one blood result.

What happens during assessment?

Your medical history, examination and pattern of illness guide testing. Blood tests may assess different parts of immune function, and selected people need genetic investigations. The IDF diagnosis guide describes the approach. A clinician interprets results alongside the clinical history.

If you are concerned about repeated or unusually severe infections, bring a record of what actually happened. Dates, diagnoses, treatment and hospital visits are more useful than trying to remember everything under pressure. Include medicines that could affect immune function; do not stop them yourself.

Prepare a short record

• List infections, where they occurred and whether laboratory results are available.
• Record treatment, how well it worked and whether you needed hospital care.
• Bring previous blood results and a complete medicine list.
• Note family history and other symptoms you want to discuss.
• Write down your main question: diagnosis, treatment, prevention or follow-up.

Ask which findings remain uncertain and who will explain the next results. If you are referred, confirm where to go and what documents to bring. Our appointment guide can help.

Get an individual prevention and illness plan

Ask your clinician which symptoms need prompt contact and what to do out of hours. Severe breathing difficulty, collapse or new confusion needs emergency help, not a routine message. If you already have a specialist illness plan, follow it.

Vaccination advice depends on the condition and treatment. Check your own plan rather than assuming all vaccines are either suitable or unsuitable. See IDF’s vaccine information. Practical support with transport, appointments and daily tasks can be discussed through our Support Hub.

General health information, not an individual diagnosis or treatment plan. Sources checked on 16 September 2026. International sources may describe services or medicines that differ from those available in South Africa. The featured image is illustrative.

Prepare for the next assessment

1. List important infections, hospital stays and unusual treatment responses with dates.
2. Bring previous blood results and a full medicine list.
3. Write down relevant family history without assuming relatives have the same condition.
4. Ask which tests are needed and who will explain the results.

Keep a copy

Save the agreed plan and review date with your appointment notes. Our resources can help you find further information.