Crohn's disease
This is a long-term inflammation that the immune system, for reasons nobody has pinned down, aims at a person's own bowel.
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Medicines commonly prescribed for Crohn's disease
For informational purposes only. Always consult a doctor before using any medicine.
Dosage form: MODIFIED-RELEASE POWDER/GRANULATE, 2 gActive substance: mesalazineManufacturer: Ferring S.A.Prescription requiredDosage form: RECTAL LIQUID, 4 gActive substance: mesalazineManufacturer: Ferring S.A.U.Prescription requiredDosage form: MODIFIED-RELEASE POWDER/GRANULATE, 4 gramsActive substance: mesalazineManufacturer: Ferring S.A.Prescription required
This is a long-term inflammation that the immune system, for reasons nobody has pinned down, aims at a person's own bowel. It can appear anywhere in the digestive tract, from the mouth to the anus, but most often it goes for the end of the small bowel and for the colon. The disease runs in waves, with quiet spells giving way to flares. There is no cure that ends it for good, yet it can be held quiet for years, and how early treatment starts makes an enormous difference. It usually announces itself in teenagers and young adults, though it can begin at any age.
What is actually happening in the bowel
Crohn's disease has two features from which almost everything else follows. The first is that the inflammation goes through the full thickness of the bowel wall, not just the inner lining. That is where complications impossible with surface inflammation come from: scarred narrowings, tunnels burrowing into neighbouring organs, and abscesses. The second is that affected stretches alternate with healthy ones, so the inflammation comes in islands, and two people with the same diagnosis may have nothing in common in their symptoms.
Why the immune system behaves this way is not fully understood; inherited tendency, the make-up of the gut bacteria and outside circumstances all play a part. One thing is certain: the risk is higher if a close relative has the disease, and considerably higher in smokers. Sometimes the whole thing starts shortly after a bout of gastroenteritis.
How it shows itself
Which complaints appear depends on which part of the gut is involved.
- Diarrhoea, often long-lasting, and with blood or mucus when the colon is affected.
- Abdominal pain, usually low on the right, cramping, and worse after eating.
- Weight loss without dieting, loss of appetite, exhausting tiredness, a low fever.
- Mouth ulcers that will not heal.
- Pain, fissures, lumps and discharge around the anus, a common form of the disease in its own right, embarrassing to mention and important to mention.
- In children, slowed growth and delayed puberty, sometimes before any bowel symptoms at all.
The abdomen is not the end of it: the joints, the eyes and the skin can become inflamed, anaemia develops, and over a long course the bones lose strength. A red painful eye with sensitivity to light is looked at urgently, so as not to lose sight.
A similar picture occurs in irritable bowel syndrome, ulcerative colitis, coeliac disease, diverticular disease and ordinary gut infections. These are separated by tests, not by reasoning, so trying to work it out on your own gets nowhere.
When help is needed immediately
Most questions are dealt with in due course, but some situations are counted in hours. Call for emergency help or go to hospital if any of the following appears:
- severe abdominal pain with vomiting, bloating, and no stool or wind passing at all, which is how an obstruction at a narrowed section presents;
- sudden fierce pain spread across the abdomen, a belly hard as a board, and every movement jarring, which may mean the bowel wall has perforated;
- fever with shivering, particularly together with a tender lump in the abdomen or a swelling near the anus, pointing to an abscess;
- heavy bleeding from the bowel, dizziness, weakness, fainting, a fast pulse;
- a severe flare: many bloody stools in a day together with fever, a racing heart and a sharp collapse of strength;
- a grossly swollen, tense abdomen in someone who is seriously unwell;
- any fever or sign of infection while you are taking medicines that suppress the immune system; such patients are assessed the same day.
How the diagnosis is made
There is no single test for Crohn's disease, and reaching the diagnosis often takes time, because the complaints are varied and resemble a great deal else. The starting point is blood tests, looking at anaemia, markers of inflammation, and iron and vitamin stores. Stool is examined twice: for the organisms that cause gut infections, and for calprotectin, a protein released when the bowel is inflamed. Calprotectin is usually what separates genuine inflammation from irritable bowel syndrome and decides whether endoscopy is needed.
Next comes colonoscopy, with a look at the last part of the small bowel and with tissue samples taken as a matter of course; gastroscopy is added if there are stomach symptoms. The small bowel, which the endoscope cannot reach, is assessed by magnetic resonance imaging with contrast or by a capsule study, and disease around the anus gets a separate scan of the pelvis. Ultrasound of the bowel is increasingly used for follow-up: it needs no preparation and can be repeated often.
How it is treated
The aim is twofold: put out the flare and hold the remission, judged not only by how a person feels but by the state of the lining, since a healed bowel protects better against complications and surgery. A gastroenterologist takes charge; regular reviews and blood tests are part of the deal.
- Corticosteroids bring a flare under control quickly, but their side effects rule them out for long-term use. If you cannot manage without them, it is time to change the maintenance treatment.
- Immunosuppressants damp down the immune response. They take a while to work, but they are designed for long-term use and make it possible to come off steroids.
- Biological drugs and the newer tablet treatments block particular steps of the inflammation precisely. These are now the backbone of treatment in moderate and severe disease, in disease around the anus, and where nothing else has worked well.
- Feeding with special formula in place of ordinary food for several weeks settles a flare without steroids. In children it is the preferred option precisely because it does not hold back growth.
- Antibiotics are given not for the disease itself but for abscesses and for disease around the anus.
It is worth knowing what has almost dropped out of modern regimens as well: 5-aminosalicylic acid drugs, familiar from ulcerative colitis, have not shown convincing benefit in Crohn's disease, and should not be relied on as the mainstay. Anti-diarrhoeal medicines are not harmless either: with a narrowed bowel and in a severe flare they are dangerous, and are taken only with the doctor's knowledge.
Roughly half of patients need surgery sooner or later, for a narrowing, an abscess, a fistula, or when medication cannot keep up. The affected stretch is removed, the narrowing widened, the abscess drained, and sometimes a stoma is brought out temporarily. Surgery is not a cure: the inflammation can return above the join, so drug treatment continues afterwards.
What is in your hands
First and most effective: stop smoking. This is not general health advice. In Crohn's disease smoking makes flares more frequent and more severe, raises the chance of needing an operation and of the disease coming back after one. No medicine delivers a gain of that size. Second, painkillers: anti-inflammatory drugs such as ibuprofen can set off a flare, so they are not taken without checking first, and the doctor will find a safe alternative.
- Eat properly. There is no universal Crohn's diet, while shortages of iron, vitamin B12, vitamin D and protein are common and are checked for and topped up. Cutting out whole food groups without a dietitian is a bad idea: undernutrition does as much harm as the inflammation.
- Keep a short diary of food, medicines, sleep and symptoms. Personal patterns show up far better that way than from memory.
- Where the bowel is narrowed, coarse fibre such as skins, nuts and tough vegetables is limited for a time, so as not to provoke an obstruction.
- Discuss vaccinations in advance: live vaccines are usually ruled out while you are on immune-suppressing drugs, so they are planned before treatment begins.
- Some medicines make the skin more sensitive to sunlight and raise the risk of skin cancers: protect yourself from the sun and show any new lesion to a doctor.
- Keep an eye on bone strength, especially after long courses of steroids.
Complications and living with the disease
Complications are far from rare, and that is exactly why treatment is not abandoned when a person feels well. In time the inflammation leads to a scarred narrowing of the bowel, a fistula into a neighbouring organ or out to the skin, a fissure or abscess near the anus, or a perforation of the wall. Long-standing inflammation of the colon raises the risk of bowel cancer: such patients are offered regular colonoscopy with targeted biopsies, and it is not something to turn down.
For all that, most people's lives stay ordinary. In some, the symptoms are mild and amount to more trips to the toilet and some abdominal pain; in others the course is harder. Good spells last years, and planning study, work and travel is entirely realistic. The point is to stay ahead of the disease rather than chase it.
Pregnancy deserves a word of its own. Conceiving and carrying a healthy baby usually works out, and the key is to enter pregnancy in remission: active inflammation itself hinders conception and increases the risk of complications. Plan ahead with the gastroenterologist. Most medicines pose no problem in pregnancy and are continued, but a few are incompatible with conception and have to be stopped well in advance, and that applies to fathers-to-be as well. Stopping treatment on your own on discovering a pregnancy is the commonest and the most damaging mistake of all.
Online consultation
If there is no diagnosis yet, a remote appointment can work through which tests to start with, whether to press for calprotectin and colonoscopy, and how far your picture resembles inflammatory bowel disease rather than irritable bowel syndrome. If the diagnosis is already made: whether this is a flare or not, what the prescriptions mean and what their side effects are, which vaccinations and tests to fit in before treatment starts, and how to prepare for the conversation with the gastroenterologist. Online is also a good place for what is hard to raise face to face: symptoms around the anus, and the effect of the disease on work, study, intimate life and mood. The signs listed in the emergency section are not assessed remotely; with those you need to be in hospital.
This material is for information only and does not replace medical advice.
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