Recurrent abdominal pain in children

Is recurrent abdominal pain the same as chronic abdominal pain?

Most doctors use the term 'recurrent abdominal pain' to mean that your child has experienced tummy pain on and off, over three months or more. Many doctors now use the term 'recurrent abdominal pain' as a label only for those cases of on-and-off tummy pain for which no other medical cause has been found.

What can cause abdominal pain in children?

The list of possible causes of recurrent abdominal pain (RAP) is long BUT the list of probable causes in a child who is well between episodes is very much shorter.

Probable causes of RAP

These include:

• Functional bowel disorder: most children with RAP have no detectable physical cause. In this case, a diagnosis of functional bowel disorder will be made. If other parts of the body are also affected, it is called functional bowel syndrome.

• Irritable bowel syndrome (IBS). Usually more commonly seen in adults, IBS can affect children too.

• Functional dyspepsia - this is indigestion with no physical abnormality of one part of the upper gut.

• Abdominal migraine: this is the cause in 1-2 in every 10 children with RAP.

• Constipation.

• Mesenteric adenitis: this is inflammation or swelling of the lymph glands in the tummy, which become inflamed and tender. It is common in children aged less than 5 years, who have much larger lymph glands in their tummies than adults do, and is usually caused by viral infections. It usually settles down in 2-3 days but will return with other viral infections - of which young children get many.

• Bladder (urinary tract) infections.

• Coeliac disease: this results from an immune reaction to gluten. It affects around 1 in 100 people in Northern Europe and the USA. It can cause recurrent tummy ache made worse when food containing gluten has been eaten.

• Lactose intolerance: this is a common digestive problem where the body is unable to digest lactose, a sugar mainly found in milk and (to a lesser extent) other dairy products. The child complains of symptoms within a few hours of eating food that contains lactose. They include wind, diarrhoea, bloating, tummy pain and feeling sick (nausea). Lactose intolerance comes on with age and is more common in older children and adults, affecting around 10% of white Europeans and 90% of South Asian, African or South American people.

• Giardia infection: this is a digestive infection which doctors used to believe was mainly caught overseas - but which we now know is also found in the UK. Symptoms include wind, diarrhoea, bloating, tummy pain and feeling sick (nausea).

Possible causes of RAP

These include:

• Inflammatory bowel disorders: Crohn's disease and ulcerative colitis. These conditions usually lead to blood or mucus in the stools and to repeated diarrhoea. Children can be quite unwell during attacks. The conditions can begin at any age and they often run in families.

• Kidney disorders such as kidney stones.

• Pains related to periods, including period pain and ovulation pain.

• Tumours in the abdomen: these are rare. Weight loss and night sweats are other common symptoms.

• Inflammation of the pancreas: pancreatitis is very uncommon in children but it can result from abdominal injury, some illnesses and some scorpion bites.

• Stomach ulcers: these can occur in children, particularly if they have used non-steroidal anti-inflammatory drugs. The pain is typically made worse by eating.

• Sickle cell disease.

• Bezoar (a ball of swallowed material that gets stuck in the intestines). This is fairly unusual now. In the nineteenth century, chewing gum was a culprit.

• Swallowing of air (aerophagy).

• Injury, particularly to the spleen: this can occur during contact sport.

• Lead poisoning: this is rare and causes many vague symptoms, including tummy pains, being sick (vomiting) and weight loss. Lead-based paint and paint dust in old buildings are the likely cause in children.

• Severe worm infestation: unusual in developed countries, this is particularly seen with roundworm infestation in Africa, Asia and Latin America.

• Tuberculosis: this is a rare cause in the developed world but common worldwide. In the UK it more usually presents with a cough.

Non-abdominal causes of RAP

Occasionally a physical problem outside the tummy can cause RAP. This explains why your doctor will need to examine, for instance, the testicles and groin of a boy with RAP. Recurrent pain in the tummy may be referred from:

• The testicles or ovaries.

• The joints of the back.

• A hernia in the groin.

RAP after gastroenteritis

Bacterial gastroenteritis can occasionally seem to trigger IBS. This may just mean that the bowel is sore and taking its time to settle down. Researchers do not know why gastroenteritis leads to IBS in some people and not in others. It is not clear whether IBS caused in this way is just as likely to persist as IBS which starts by itself.

How can so much pain have no physical cause?

Pain is created in the brain out of a mixture of nerve and chemical signals. These include signals from injured tissues - but these do not provide the only 'input' to the pain centres of the brain. These areas also receive input from the thinking and emotional parts of the brain, and we know that these can modify and even create pain.

What are the symptoms of recurrent abdominal pain in children?

RAP is recurring pain in the tummy which has continued, on and off, for three months or more.

In RAP that is not caused by a physical condition, the pain is usually around the belly button. There is often a headache. Feeling sick (nausea) and even being sick (vomiting) are fairly common. However, your child is well between attacks and is otherwise healthy - growing well and, generally eating and drinking normally. There are no 'alarm symptoms' (see below).

The patterns of RAP that doctors describe, and which are NOT associated with a physical condition, are: irritable bowel syndrome (IBS, the most common), functional abdominal pain, functional abdominal syndrome, functional dyspepsia and abdominal migraine.

What is childhood IBS?

IBS is remarkably common in adults, affecting up to 1 in 5 people at some point. While it is most commonly diagnosed in young adults, it can start at any age. In fact, one US study suggested that 1 in 16 children aged 11-13, and almost 1 in 7 teenagers, experience IBS-type symptoms.

The causes of IBS in children are thought to be similar to those in adults. Although there is no problem with any one part of the gut, it's thought that the different bits don't work smoothly together. In addition, the gut may be hypersensitive to pain signals and the nerves or muscle of the gut may be overactive.

IBS may be the cause if your child has abdominal pain which can be made better by going to the toilet (for a poo), or pain which is associated with needing to poo more often or with the poo being different. IBS is diagnosed if your child has abdominal pain or discomfort and a change in bowel habit.

Other symptoms of IBS in children may include diarrhoea (often several times a day, often with a 'rush' to go), constipation (hard, dry stools; infrequent bowel movements or straining to have a bowel movement, passing mucus, and feeling bloated). Symptoms may occur after eating.

You can find out more in our separate leaflet called Irritable Bowel Syndrome (IBS).

What is functional abdominal pain like?

The tummy pain is typically around the belly button. Your doctor finds no signs or symptoms that point to a physical condition causing your child's pain. They are well between episodes and are not losing weight. They may be quite anxious about the pain and about the effect that it is having. Most children experiencing RAP will have functional abdominal pain.

What is functional abdominal pain syndrome like?

This occurs when your child has functional abdominal pain but also has symptoms affecting other parts of their body at the same time, such as headache, pain in the arms or legs, or difficulty sleeping.

What is functional dyspepsia like?

This occurs when the pain is high in the tummy - above the belly button - and not made better by going to the toilet (for a poo). There may be symptoms of indigestion, such as belching and pain after eating.

What is abdominal migraine like?

Your child has recurrent sudden episodes of pain around the belly button which last for over an hour, and which interfere with normal activities. During attacks your child is off their food, may have nausea or vomiting, and may also have headache, turn pale and be intolerant of light. Between episodes your child is perfectly well.

What symptoms of recurrent abdominal pain suggest a physical cause?

Tummy pain due to physical causes can occur anywhere in the abdomen, including around the belly button. However, it is most often in the lower abdomen, either just above the pubic bone or in the bottom right or left corners, or in the upper right corner just under the ribs. Most physical causes do not run in families (exceptions to this are inflammatory bowel disorders such as Crohn's disease and ulcerative colitis, and coeliac disease).

Signs which suggest a physical cause

These include:

• Constipation (which may co-exist with RAP).

• Repeated or persistent sickness (vomiting).

• Chronic or severe diarrhoea.

• Unexplained high temperature (fever).

• Blood in the stools, or black stools.

• Waking at night - due to pain - to have a bowel movement, or diarrhoea at night.

• Losing weight.

• Joint pains.

• Symptoms which are worsening over time.

If one or more of these symptoms are present, this does not mean that your child is seriously ill, or that you should be alarmed. They are sometimes called 'alarm' symptoms because they set off an alarm in the mind of a doctor, reminding them to consider other physical causes for the pain.

If everything is physically normal, what causes my child's pain?

Experiencing pain when there is no underlying physical problem is surprisingly common. It can be difficult for children, who may feel as though their friends and family will think they are inventing the pain or that they are suspected of imagining it. It is important to explain that you know that their pain is real and that it needs to be managed and treated just as much as if it came from a broken bone.

Pain and the brain

Although injury, pressure and stretching of our bodily tissues cause pain, the sensation of pain can also be made, increased or altered by the brain. There are pain 'centres' in the brain, which receive signals from body tissues but also from the thinking and emotional areas of the brain. The final pain sensation is created by the brain from all three.

Many of us will have experienced the brain's effect on pain: we get headaches when worried, feel sick when given bad news and develop loose stools when anxious. In the same way, stress can affect physical pain - for instance, by making even normal activity of the bowel painful.

We are more likely to feel pain - or feel the pain more intensely - when we are expecting pain, where we believe we have a worrying illness, or where we are anxious or depressed. Focusing on the location of a pain will sensitise the nerves and make it worse. People sometimes use a technique of focusing on another part of their body to manage pain - for example, clenching fists or focusing on toes when having an injection.

The body may create the sensation of pain as a substitute for the sensation of other distress such as bullying, unhappiness at school, worry about exams, worries about friendships or worries about weight and body image. Distress may be experienced as real tummy (abdominal) pain, headaches or both.

In IBS, doctors additionally believe that the intestines are abnormally sensitive and overactive, which is a major source of pain.

What helps abdominal pain in children?

We know that painkillers are not always particularly helpful in this form of 'brain-induced' pain and that painkillers come with side-effects. In many cases, the side-effects may include making the bowel more sensitive, or upsetting the normal working of the bowel by causing constipation or indigestion. However, understanding how the pain is made shows us that working on the emotional and anxious areas of the brain through reassurance is more likely to be effective.

We also know that the body contains natural pain-reducing substances, including adrenaline (epinephrine), cortisol and endorphins. This is why, in a sudden accident, even a severe injury is often not initially painful. It also means that increasing levels of these positive chemicals can be helpful.

Endorphins, for example, are increased in exercise, and adrenaline (epinephrine) by both exercise and excitement. It follows from this that if your child is able to increase their exercise levels and to find enjoyable and fun things to do, this is more than a distraction - it will also have a direct and real effect on the pain and it may allow them to feel more in control of their situation.

What will the doctor want to know?

The doctor will often make the diagnosis of RAP based on the questions they ask you and your child, and on the examination they make of your child. They will want to know:

Questions about the pain

• Where the pain is.

• What it feels like - how severe it is and what sort of sensation is felt.

• When it began, how often it comes and how long it lasts for.

• Whether it is getting gradually worse, is variable, or is always the same.

• Whether it makes your child feel that they need to go to the toilet and, if so, whether going to the toilet helps.

• Whether it is affecting daily activities - school, or fun things, or both.

Questions about your child

• They will ask about your child's recent and general weight gain.

• They will ask about your child's diet and whether you have noticed any particular reactions to certain foods such as bread (gluten) or milk (lactose).

• They will ask what their bowels are usually like and whether their stools are any different at the moment (you may need to have a look before you see the doctor, although you do not usually need to bring a sample at the first appointment).

• They will ask whether they have any urinary or genital symptoms such as pain on passing urine, or itching or discharge in the genital area.

• They will want to know about any recent illnesses. Many common childhood conditions can cause enlargement of the immune (lymphatic) glands in the tummy, which can lead to episodes of recurrent tummy pain. This is very common in younger children.

• In older girls your doctor will want to know about periods - if they have begun, or you are expecting them soon because other signs of puberty have appeared.

• They will want to know about any recent foreign travel and immunisations.

• They will ask about your child's previous medical history and family history, including the health of siblings. They will be interested in any physical bowel disorders and in any RAP or IBS in other family members.

Your doctor will check your child's height and weight and will examine your child's tummy, to see how tender it is and where it is sore.

How will the doctor make the diagnosis?

In most cases of RAP the diagnosis is made by your GP after taking a clear history and examination and checking carefully for 'alarm' signs and for anything that suggests a physical cause, such as constipation or lactose intolerance. Your GP may do some tests to exclude coeliac disease. If lactose intolerance is suspected they may also suggest a food diary and some trials to see if excluding milk is helpful.

Your doctor is likely to want to review your child, after an interval has passed, to see whether things are settling down and to make sure that things aren't changing and that your child - even if they still have some symptoms of RAP - is feeling better.

How will my child's recurrent abdominal pain be investigated?

Most children with RAP do not need investigations, because their symptoms and examination findings point so strongly to one of the common patterns of RAP. However, because coeliac disease and infection with giardia are both common possibilities which are easily ruled out (and which mimic IBS), these basic tests are commonly offered:

• Blood tests: these can look for conditions such as coeliac disease and inflammatory bowel disorders, for anaemia and for general inflammation. In the UK doctors generally test anyone with repeated abdominal pain for coeliac disease, as it is fairly common. If your doctor did not mention it, it may mean your child has been tested before - but ask them.

• Urine tests: to rule out infection.

• Stool examination: to rule out giardia and other infections and to look for blood.

If your child is upset at the thought of a blood test then ask the doctor how necessary this is. If the doctor feels that coeliac disease is very unlikely in your child's case, and everything else suggests to the doctor that there is no physical cause for the pain, then a blood test is very unlikely to be helpful.

However, if your doctor feels that your child's signs or symptoms suggest a physical cause for the pain, further investigations will be needed. These may include:

• Imaging tests: such as X-rays or ultrasound. These are not usually suggested without clear reason.

• Abdominal ultrasound: this is used if the doctor suspects that any of the abdominal organs feel abnormal.

• Computerised tomography (CT) and magnetic resonance imaging (MRI) scans: these are not generally done, unless something abnormal has been found on other tests.

• Colonoscopy: a colonoscopy or a sigmoidoscopy is reserved for children in whom inflammatory bowel disease is suspected. These tests are usually performed by a specialist.

• Gastroscopy: gastroscopy is reserved for children in whom ulcers or other conditions of the stomach or small intestine are suspected.

How can I be sure my child doesn't have a rare and serious condition?

Your doctor will investigate your child to rule out all causes that seem possible, based on the symptoms and examination.

If everything tests as normal, and your child is not getting worse and is well between attacks, it is extremely likely that your child has no physical illness causing their pain. Further testing for rare conditions that don't 'fit' the picture is thought to be a bad thing, as this is likely to make your child more anxious, which is likely to make the pain worse.

Serious conditions generally show themselves quickly because they get worse and because they show alarm signs. However, if your child is diagnosed with RAP and then new symptoms develop, you should return to your doctor and ask for another review.

How is recurrent abdominal pain in children treated?

If your child has an underlying physical cause for their RAP, such as constipation or coeliac disease, treatments will be directed at that cause, and are not described here.

Most children with RAP without physical cause get better with reassurance that there is nothing physically wrong and with an explanation of the source of the pain.

Various other things may be helpful, including:

Talking therapies

If children are stressed by RAP, and if they continue to miss school and other activities, a type of counselling called cognitive behavioural therapy (CBT) may be helpful. CBT helps people to change the way that they think about stressful things.

Family therapy, in which other members of the child's family are involved in the therapy, can be useful, particularly if other members of the family are experiencing anxiety. Other forms of talking therapy such as hypnotherapy are also sometimes used. Hypnotherapy probably affects the way the brain deals with pain.

Medication

Medicines are not usually recommended for children with RAP, unless they have severe symptoms which have not responded to simple management. Medicines are often not very effective for pain originating in the brain, and the side-effects of many medicines can make tummy pain worse.

Dietary changes

It has been suggested that children are less likely to experience RAP if they have a good proportion of fruit in their diet. It is not, however, clear that modifying the diet once you have RAP is helpful.

There is no evidence that fibre supplements or lactose-free diets are helpful for most children. Some children with IBS (see below) may benefit from fibre - but this must be of the soluble type. Insoluble fibre makes things worse.

It is always the case that a balanced, healthy diet containing sufficient fibre, fruit and vegetables is generally better for your child's health.

Children who have proven food intolerances, such as lactose intolerance, will benefit from excluding those items from their diet. In the case of lactose intolerance, this condition is not an allergy but an inability to process lactose in the bowel. It therefore does not usually need to be absolutely excluded from the diet, just reduced.

Alternative approaches

True food intolerance can only be diagnosed by stopping and then trialling the relevant food. Allergy tests offered by alternative practitioners, such as hair tests or tests involving placing food on the skin, are not supported by evidence. This means that they do not produce medically accepted results.

If following such advice and applying exclusion diets as a result, be very aware of your child's need for a balanced diet with sufficient calories and nutrients to support growth and development, energy, learning and exercise. Restrictive diets are potentially harmful, so please consider talking to a health professional before making this choice for or with your child.

Hot water bottle

The power of the hot water bottle to make children feel better should not be underestimated. A hot water bottle, or a microwave-warmed grain bag, can be very helpful. This isn't just a 'placebo' - adding warmth to the sensations on the tummy can 'override' the pain nerves and reduce the sensation of pain.

Exercise and distraction

As explained under the section which explains the pain, boosting the levels of the body's natural painkillers such as adrenaline (epinephrine), cortisol and endorphins will reduce the sensation of pain.

The best ways to increase levels of these natural body chemicals include exercise and fun or exciting activities. This may not always be easy (or even possible) for your child whilst they have pain. However, there is evidence that increasing these activities when your child does not have pain will then benefit them when they do.

Distraction can also be helpful during episodes of pain. Focusing the mind away from the pain will reduce its impact. Most parents are very experienced in distracting their child from pain - reading, films and TV, music and conversation are all likely to help your child feel better during attacks.

Helping them keep up with schoolwork if absent from school may also help them feel better, as they may be less worried.

Management of IBS in children

The symptoms of IBS can often be treated with a combination of the following:

• Adjustments to diet, including eating smaller meals more often, or eating smaller portions, and eating meals that are low in fat and high in carbohydrates.

• Medications (see below).

• Probiotics are helpful for some children.

• Increased exercise.

Certain foods and drinks are thought to cause IBS symptoms in some children, such as milk products, caffeine drinks, artificial sweeteners and gas-producers such as cabbage and onions. Children should be given plenty of fluids that are water, or water-based. It is not a good idea to exclude everything at once: keeping a food diary can help work out whether any foods are triggers.

Dietary fibre can lessen constipation in children with IBS but it may not help with lowering pain.

Medications for IBS
Medications are sometimes used in childhood IBS. They include:

• Fibre supplements and/or laxatives when there is constipation.

• Antidiarrhoeal medicines to reduce diarrhoea in IBS (this can make pain worse).

• Antispasmodic drugs to try to reduce bowel activity and, therefore, pain (which is often worse after eating, so they are taken at mealtimes).

• Probiotics: live micro-organisms such as bifidobacteria improve symptoms of IBS in some children.

• Rarely, antidepressants are used to modify the pain but these medicines can have powerful side-effects so are only used in children by specialists.

What is the outlook for children with recurrent abdominal pain?

RAP usually settles down over time. However, it can persist for a while. It is more likely to persist if it has been going on for a long time - more than six months - before medical advice has been sought. It also seems as though it is more likely to continue if parents are very stressed, or families experience lots of stressful life events.

Some children who experience RAP will go on to experience IBS in adulthood. This is particularly the case where others in the family are affected by IBS.

Dr Mary Lowth is an author or the original author of this leaflet.