Understanding the immune system's role in chronic disease is fundamental to treating it well. Rheumatic disease is frequently multi-system: lupus can involve the skin, joints, kidneys and blood at once, and vasculitis can present to an ENT surgeon, a nephrologist and a neurologist in the same month. Clinical immunology is the discipline that looks at all of that as one problem.
What clinical immunology is
Clinical immunology is the branch of medicine that deals with the immune system going wrong. Broadly that happens in two directions: the immune system attacks the body's own tissues, as in autoimmune disease, or it is too weak to fight infection, as in immunodeficiency.
In India the speciality is usually trained together with rheumatology, as a single DM in Clinical Immunology and Rheumatology. In practice most of the work is autoimmune and inflammatory disease: lupus, Sjögren's syndrome, systemic sclerosis, antiphospholipid syndrome, the vasculitides and inflammatory muscle disease, alongside the inflammatory forms of arthritis.
How it changes the approach
Precision diagnostics. Antibody testing is powerful but easily over-interpreted. ANA, anti-dsDNA, anti-Ro, ANCA, antiphospholipid antibodies and complement levels each answer a specific question, and each is useful only when that question has been asked. Knowing which tests to order, in which sequence, and how to read a positive result in context prevents both missed diagnoses and unnecessary alarm. A positive ANA test is the commonest example of a result that frightens people for no good reason.
Personalised treatment plans. Two people with the same diagnosis may need very different treatment depending on which organs are involved, their other illnesses, plans for pregnancy and how they responded to earlier medicines. Treatment ranges from hydroxychloroquine and methotrexate to stronger immunosuppressants and biologic medicines, and the choice is rarely the same twice.
Management of complex conditions. Systemic lupus erythematosus, vasculitis and antiphospholipid syndrome demand a view of the immune system as a whole, coordinated with nephrology, pulmonology, dermatology and obstetrics as needed. The rheumatologist is usually the person who holds that plan together.
Safety: the other half of immunology
Medicines that calm the immune system also reduce its ability to fight infection. Part of the specialist's job is managing that trade-off: checking for hidden tuberculosis and hepatitis B before stronger treatments are started, bringing vaccinations up to date before immunosuppression begins where possible, and making sure people know which warning signs of infection need urgent care. Infection and vaccines on immunosuppressive treatment covers this in detail.
Procedures in the same hands
Alongside this, procedural skill — joint aspiration and injection, nail fold capillaroscopy, minor salivary gland biopsy — keeps diagnosis and treatment in the same pair of hands, so a question raised in the clinic can often be answered in the same place.
When it is worth seeing someone
Symptoms in more than one system at once — joint pain with a rash, dry eyes with swollen glands, colour-changing fingers with reflux and breathlessness — or an autoimmune blood test that has come back abnormal are the usual reasons. When should you see a rheumatologist? lists the patterns in full.
Common questions
Is a clinical immunologist the same as an allergist?
Not quite. Clinical immunology covers the whole immune system: autoimmune disease, where it attacks the body, and immunodeficiency, where it is too weak; some training programmes include allergy as well. In India it is usually trained together with rheumatology, and the work centres on autoimmune and inflammatory disease.
Why are so many antibody tests ordered in autoimmune disease?
Each antibody points towards particular conditions or particular organ risks, so a small panel chosen for the symptoms can narrow a diagnosis quickly. A large panel ordered without a clear question tends to produce borderline results that mean little and cause a great deal of worry.
Does immunosuppressive treatment mean frequent infections?
It raises the risk, and by how much depends on the medicine and the dose. Screening for tuberculosis and hepatitis before treatment, keeping vaccinations up to date and acting early on a fever are what keep that risk low.
Sources
- NIAMS — Autoimmune diseases www.niams.nih.gov
- MedlinePlus — Autoimmune diseases medlineplus.gov
- MedlinePlus — Immune system and disorders medlineplus.gov
- NHS — Lupus www.nhs.uk
- NHS — Vasculitis www.nhs.uk
This article is general information and does not replace a consultation.