Authors: Scott Pereira
Publication date: 18 Sep 2004
You'll need to know your complement from your cytokines, but there's a lot more to clinical immunology than cutting edge science, says Scott Pereira
Immunology is a small specialty. I've been trying to think what its USP (unique selling point) is—some unique specialist procedure perhaps. Haematology has bone marrows and histopathology has autopsies. I suspect that for immunology it's simply the different way of looking at disease; using the cutting edge of immunological science (far too much of it even for immunologists, let alone the generalist) to try and help patients with whom other clinicians have got to the end of their diagnostic road.
Immunologists boldly go into esoteric and confusing areas that others often bypass because of the nomenclature, the jargon, or the apparently highfaluting immunophilosophy. As haematologists are confident with clotting cascades, and microbiologists with the minutiae of resistant bugs and antibiotics, so immunologists can explain complement, cytokines, and lymphocyte receptors. They can even remember all those types of hypersensitivity and immunodeficiency and how they may present clinically.
Strong science base
Immunologists who do a lot of teaching are frequently asked by students how they can become clinical immunologists; they see it as an intellectually challenging and fulfilling job. Often this is early in the course, when students with intellects the size of a planet (most of them, nowadays) realise that they are going to have to knuckle down to five or six years of knowledge acquisition; they sense that the science base of immunology is nearer the surface than is most of the stuff they have to learn.
How do immunologists acquire this rarefied skill and knowledge base? Some begin as an undifferentiated immunoblast, perhaps doing a BSc project in an immunology laboratory as a medical student and starting to develop receptors for the growth factors that good teachers produce. This can be the equivalent of thymic education; many lymphocytes are lost, but those that have the right receptors should come out motivated and ready for more.
Advantages and disadvantages of being an immunologist
Cutting edge science—opportunities for research
Conditions affect all ages and all body systems
Sound and supportive patient self help groups
Interesting colleagues and a supportive consultant network
Still often singlehanded consultant practice
Fighting other pathology specialties for their jealously guarded immunology tests
Excessive inappropriate referrals for food “allergy” and “ME”
These days it is usually necessary to be dually qualified, with an MRCP (membership of the Royal College of Physicians) and an MRCPath (membership of the Royal College of Pathologists), which in practice means many years of training. There are just 33 NTNs (national training numbers) for MRCPath training in immunology. There is a feeling that a higher degree helps, even if only to sustain credibility in the academic centres in which most consultants work. Hence many immunologists have a PhD or MD, giving them a specialised laboratory background and research portfolio that provides the Zen that helps later with the art of grant funding maintenance. Although this can delay the magical CCST (certificate of completion of specialist training), time out for a research degree with a maintained NTN is strongly encouraged.
Too few centres
Most of the specialist centres nationally have trainees, but there are all too few centres. There is a flourishing training programme organised under the auspices of the Association of Clinical Pathologists, so all trainees meet every couple of months in a different centre over a three year cycle. Most specialist centres now have two consultants, and one of the pair may (rarely) be a non-clinical scientist of consultant equivalent status. Higher specialist training for the scientists follows the same schedule as the clinician training (PhD rather than MRCP required), and the examination for MRCPath should be tailored for the non-clinician.
The fully fledged consultant immunologist has core skills that include running an immunology laboratory and providing for specialised immunodeficiency clinics (see box). The laboratory usually provides a service for at least one district general hospital (DGH) or medical school centre, and may also be involved in a network of other small laboratories that provide a limited immunology service. This may mean visits to support outside labs, perhaps with a specialist outpatient clinic organised as part of the visit. There is a move towards insisting on accreditation of the centres that provide specialised immunodeficiency clinical services, and these will have a critical mass of patients with antibody deficiency on replacement immunoglobulin. This centralises the skills and experience needed for these rare conditions.
Apart from this core clinical workload, most clinical immunologists are involved with the broader immunological repertoire, including vasculitis, connective tissue disorders, and advice on immunosuppressive agents such as those used in transplantation. A few are in centres with responsibility for histocompatibility and immunogenetics services, although many of these centres are run by non-clinical scientists. Although AIDS is a classic secondary immunodeficiency, few clinical immunologists are heavily involved in direct clinical care of these patients.
Allergy and desensitisation
In the United Kingdom, unlike in many other parts of the world, allergy services (“allergology”) are not always seen as core clinical immunology, and there is some controversy about the status of the training and skills of the immunologist compared with that of the specialist with a CCST in allergy. MRCPath training comprises a significant amount of clinical allergy, usually including desensitisation immunotherapy (which is a hospital based procedure), and many immunologists will be involved with such clinics to provide for the strong demand, for which there are currently insufficient allergists to cope. Most immunologists, however, try to avoid building up a practice in the heart sink areas of chronic fatigue syndrome and multiple allergy syndrome.
Immunology has a strong research and academic base, and many immunology departments are based in medical schools, with the expected additional pressure for teaching and research. Immunologists are involved in a rapidly developing subject, and need to be familiar with providing updates for colleagues and managing change in the laboratory.
As in many small specialties, there is strong mutual support, particularly for newly appointed and singlehanded consultants. Looking around at my colleagues, I find the great variety of interests and personalities intriguing—it's never boring, and you can't tell an immunologist. Well, not much.
A summer Friday in the life of this immunologist
0730 Early morning regular clinic for clinical trial of grass pollen desensitisation of hayfever sufferers; 10 patients for maintenance injections to chat to and watch for an hour for any reactions (none so far in this cohort)—finished by 0900 so they can all get to work.
0930-1200 General immunology/allergy clinic: strictly a one stop shop (no allergy follow ups) for six new patients including a baby with a rash needing some imaginative skinprick testing procedures on a squirming back, and angioedema and cough in a patient on ACE inhibitors (a side effect which we could probably have diagnosed from the referral letter). One patient in for his regular intravenous immunoglobulin infusion sits in the next clinic room, checked regularly by our very capable clinic nurse, who also does most of the skinprick tests.
Lunchtime Hospital grand round. Chat to a rheumatologist about whether he wants the new test for antibodies to CCP rather than old fashioned rheumatoid factor to sort out his early rheumatoid patients who have bad prognoses before putting them on the new biological anti-TNF therapies. Of course he wants the tests, but who's going to pay for them?
1400-1700 Laboratory meeting in the afternoon to discuss new equipment and who is going to write the business plan for it, if needed. Luckily there is a CPA (clinical pathology accreditation) recommendation for an upgrade after a recent inspection, so a bit of a no-brainer. Check the problematic test requests and comment on a couple of odd results, including an “urgent” ANCA with an equivocal assay result that they want to immunosuppress over the weekend.
1800-1900 All right, I admit it; visit to a local private hospital to see a couple of patients who don't want to wait for an allergy clinic appointment, and want to be desensitised for hayfever. Assessed, agreed, scheduled. Why do we have to fight for funding for this treatment for our NHS patients, except on clinical trials?
1900 Home for a swim off the yacht. I live on an old classic yacht rather like the one on which Portier and Richet discovered anaphylaxis at the turn of the last century. Check emails and write this.
Scott Pereira consultant immunologist
Northwick Park Hospital, Harrow