Enteropathic arthritis (IBD-associated)

In this condition the joints, and the entheses, where tendons fix into bone, are inflamed by the immune process that lies under the bowel inflammation of inflammatory bowel disease. The most widely held view is that inflammation starting in the wall of the gut reaches out to the joints and the spine, so the bowel and the joints are two sites of one disease rather than two unrelated problems.

There is no single cause. An inherited tendency plays its part, and the gene marker HLA-B27 goes particularly with spinal involvement, though many people with the condition do not carry it. Psoriatic arthritis and axial spondyloarthritis are its relatives in the spondyloarthritis family. Most people who have it already live with Crohn's disease or ulcerative colitis, but once in a while the joints flare before the bowel condition is known.

The joints can be affected in more than one way. Watch for:

• Sore, swollen joints in the arms or legs, which may flare when the bowel does
• Pain and stiffness in the back or buttocks when the spine is affected, often easing with movement and stiffening with rest
• Pain at a tendon's attachment, at the heel for example
• A finger or toe swollen from tip to base

The diagnosis hinges on connecting the gut with the joints. What your joints are doing, whether you have had inflammatory bowel disease, the examination and the right tests and scans all feed into it, and sometimes the joint symptoms come before anyone knows about the bowel condition.

An ultrasound scan can help to show an inflamed joint or tendon attachment. Point-of-care ultrasound is part of the consultation with Dr Borukhson, so it is often done at the same visit. For the scan itself, the ultrasound clinic page goes into detail.

Treatment sets out to settle the inflammation in the joints with the bowel condition kept in mind throughout, because some treatments act on both. It is planned around you, and often goes best when the rheumatology and gastroenterology teams work in step. If one joint stays troublesome, an ultrasound-guided injection into it may help.

The bowel shapes the choice of medicine. Joint pain can be eased by anti-inflammatory tablets (NSAIDs), but they are kept to a minimum here, the bowel sometimes reacting badly to them. If the joints need more, the choice often leans towards medicines that treat the gut as well. Among the disease-modifying tablets (DMARDs), sulfasalazine does both, and methotrexate can too in Crohn's disease, though it is not usually used for colitis; for more active or persistent disease, the choice is a biologic, such as one of the anti-TNF treatments, several of which also treat inflammatory bowel disease. The medicines that block the action of a messenger called interleukin-17, secukinumab and ixekizumab among them, are a notable exception: they help related kinds of arthritis but can worsen the bowel, so they are generally left out here. Any DMARD or biologic comes with regular monitoring, and screening is done before a biologic starts. Methotrexate can weaken the immune system, so infections are harder to fight off. You agree the plan, and it is matched to the treatment your gastroenterology team gives.

The bowel and the joints both tend to do better when they are looked after together. Staying in touch with your gastroenterology team, going to your reviews and taking your bowel treatment as agreed all count, since a calmer gut often means easier joints.

• Stay on the move with regular gentle activity and stretches; physiotherapy helps a lot where the spine is affected
• Be wary of anti-inflammatory tablets bought over the counter, which can upset the bowel, and ask before taking them
• Stopping smoking is particularly worth doing, since smoking can make Crohn's disease worse
• During a flare, pace yourself and rest sore joints, then build up your activity again

Most people do well. In many people the condition settles, or comes and goes in a pattern that treatment controls well, and with the two specialties working together, most stay active.

Once the arthritis is diagnosed, a routine review with your rheumatology or gastroenterology team is the place for most joint symptoms. What cannot wait, including the bowel's warning signs, is in the lists below, the most serious first, and the paragraph after the lists says what should be seen within days.

Treat any of these as a 999 or A&E emergency: call 999 and do not drive yourself to A&E.

• Severe illness with suspected sepsis: a high fever with shaking, confusion, rapid breathing, or feeling dramatically worse over hours
• With a fever or feeling unwell, a rash that does not fade when you press it, a stiff neck with eyes that cannot bear bright light, or skin, lips or tongue turning blue, grey, pale or blotchy, since these can be signs of meningitis or sepsis, as can a very bad headache, confusion or a first seizure with a fever or feeling unwell; on black or brown skin the rash and the change of colour may be easier to see on the palms of the hands or the soles of the feet
• Chest pain that is crushing, tight or like a pressure, that spreads to an arm, the jaw, the neck, the stomach or the back, that comes with breathlessness, sweating, feeling sick or feeling light-headed, or that came on suddenly and does not go away
• Vomiting blood, or bleeding from the back passage that is heavy or will not stop, most of all with faintness, confusion or pain in the abdomen, or vomit that is black or dark brown, since an inflamed bowel can bleed, and anti-inflammatory tablets can make the stomach bleed
• Lips, mouth, throat or tongue that suddenly swell, a throat that feels tight, very fast breathing or a struggle to breathe or to swallow, skin, tongue or lips turning blue, grey or pale (on black or brown skin this may be easier to see on the palms of the hands or the soles of the feet), becoming suddenly very confused, drowsy or dizzy, or fainting and not being able to be woken, since this can be a severe allergic reaction, anaphylaxis, which can follow a dose of any medicine
• Severe pain in the abdomen, or vomiting poo, since a badly inflamed bowel, or one that has narrowed or become blocked, can need treatment in hospital
• An eye that suddenly and completely loses its sight

Any of these needs an assessment that is urgent, on the same day, from your GP, your rheumatology or gastroenterology team, or NHS 111:

• A fever, or feeling generally unwell, on immunosuppressant, biologic or steroid treatment, since an infection has to be treated early
• A joint that is hot and swollen, with a fever or feeling unwell, since an infected joint has to be ruled out at once, at A&E or through NHS 111
• A joint that has become hot and very swollen suddenly, or is worsening quickly, even without a fever, since an infected joint does not always announce itself with one; a joint that will take no weight at all, or that cannot be moved, is a 999 or A&E emergency, whether or not there is a fever
• Black or dark red stools, or bloody diarrhoea, or very bad diarrhoea, or a flare of the bowel with a fever or a racing heart, or a bowel that has stopped passing wind or poo, since these have to be treated that day
• A calf that is swollen, hot or painful, or a limb that is painful, swollen or discoloured, which can mean a clot, and inflammatory bowel disease makes clots likelier; with breathlessness, chest pain, palpitations or feeling faint, this is a 999 or A&E emergency: call 999 and do not drive yourself to A&E
• A new red, painful eye, or sight that has blurred, dimmed or changed, which needs an eye casualty or urgent eye clinic the same day, as does an eye that light hurts, since this family of conditions can bring inflammation within the eye that harms the sight; our uveitis guide says more
• Being near someone with measles, chickenpox or shingles, while you take a medicine that weakens the immune system, since measles and chickenpox can be dangerous when the immune system is weakened, and you can catch chickenpox from someone with shingles if you have never had chickenpox; NHS 111 can tell you what to do that day

Short of the signs in the lists above, bowel symptoms that are new or slowly getting worse, such as diarrhoea that persists, blood in your poo or weight lost without trying, or bowel treatment that is no longer working, and back or joint pain that flares in spite of treatment, are for your gastroenterology or rheumatology team or your GP within days. Tell the team that prescribes your DMARD or biologic about any infection that is unusual or keeps coming back. If you have Crohn's disease or colitis and a joint has newly swollen but is not hot, or a finger or toe has swollen along its length, tell your gastroenterology team or see your GP within days, since a joint that is newly inflamed needs an urgent referral to a rheumatologist; a back that has begun to ache in the inflammatory way is worth raising with your GP or gastroenterology team, or with a specialist you book directly. Where the arthritis reaches your spine, the warning signs given for the back in our axial spondyloarthritis guide apply to you too. If you cannot tell how urgent something is, asking is never a mistake.

Enteropathic arthritis reaches both the joints and the gut, so the best results come from an assessment that looks at the whole person and, where it is needed, links the care between specialties. With inflammatory bowel disease, joints that begin to ache or swell, or a back that aches in the inflammatory way, deserve a specialist review, arranged through your GP or gastroenterology team, or booked directly.

How do doctors confirm enteropathic arthritis?

The diagnosis draws on how your joints behave, any Crohn's disease or ulcerative colitis you have, an examination and the right tests and scans. Seeing the link between the bowel and the joints is the heart of it, and now and then the joints play up before the bowel condition has been found. Point-of-care ultrasound is part of the consultation with Dr Borukhson, so a joint, or a tendon where it meets the bone, can often be examined for inflammation on the day.

Are my sore joints a sign that my bowel disease is flaring?

At times, yes. The joints can flare in time with the bowel, and calming the gut can then help them too. At other times the joints and the spine go their own way and need treatment of their own. That is exactly why an assessment that takes in both is useful: joint pain is not assumed to follow the bowel, and each part is treated on its own terms.

Why does my bowel condition shape the treatment for my joints?

Because it is one body. A medicine can help the joints and the gut together, or it can help one and upset the other. For that reason anti-inflammatory tablets are kept to a minimum, and a few drugs used in related kinds of arthritis, in particular the medicines that block the action of a messenger called interleukin-17, are usually not used. Treatment often leans towards medicines that work for both, and you agree the plan, which is kept in step with your bowel care so that neither undoes the other.

I already see a gastroenterologist. Do I need a rheumatologist too?

Yes; the two roles fit together. The bowel is your gastroenterologist's to treat; whether the joints or spine are inflamed, and what to do about it, is the rheumatologist's. Care shared between the two tends to bring the best result. Joint pain or swelling, or a back that stiffens with rest and loosens as you move, in someone with inflammatory bowel disease deserves a rheumatologist's opinion, through your GP or your gastroenterology team, or booked directly.

How is it different from everyday wear-and-tear aches?

It is inflammatory, not mechanical, so stiffness often worsens after rest and eases as you move, and a joint, or a whole finger or toe, can swell, or a tendon can hurt where it joins the bone, at the heel for example. It is a member of the family that includes psoriatic arthritis and axial spondyloarthritis. Ultrasound, where it helps, is one way to separate inflammation from the ordinary wear of a joint.