Diarrhoea in Children: The Real Issue Is Preventing Fluid Loss

Diarrhoea is one of the most common health problems in childhood after upper respiratory tract infections, and it can recur several times a year, especially in children under five. The great majority of cases are due to viruses, are self-limiting and resolve within a few days without any medication. But the innocent-looking face of this condition conceals the real risk: children carry far more water in proportion to their body weight than adults and lose it far more quickly. For this reason the centre of diarrhoea treatment in children is not stopping the diarrhoea but replacing the fluid and minerals lost; thanks to this simple approach, a great many children survive around the world every year. The mistake families make most often arises at exactly this point; stopping the child's feeding and fluid intake in the belief that the bowel needs to rest makes the condition worse rather than better. In this article we look at the causes of diarrhoea in children, what the right approach at home should be, which findings allow no delay, and how transmission can be prevented.

What Is Diarrhoea and How Is It Recognised?

Diarrhoea is the child's stool becoming more watery and more frequent than usual; the general definition is three or more watery stools a day, or in babies a marked increase in the normal frequency of stools. The criterion here is not an absolute number but a departure from the child's own habit, because a normal stool pattern varies greatly with age and the way the child is fed. Exclusively breastfed babies may pass loose, yellow-green, grainy stools several times a day and this is entirely normal; it is also acceptable for these babies to pass stool only once every few days. In formula-fed babies the stool is usually darker and firmer, and after the age of two most children pass a formed stool once or twice a day. The number of families who mistake their baby's frequent, soft stools for diarrhoea is therefore not small; what really needs attention is the stool suddenly becoming watery, an increase in its amount and frequency, and restlessness, vomiting or fever accompanying it. Blood in the stool, a dark tar-like colour or a heavily mucous appearance is a separate situation requiring medical assessment at any age. A distinction is also made by duration: conditions lasting less than two weeks are regarded as acute and those exceeding four weeks as chronic diarrhoea, and the latter requires an entirely different course of investigation.

Why Does Diarrhoea Occur in Children?

Intestinal infections, that is gastroenteritis, are responsible for most childhood diarrhoea, and the majority of these are viral in origin. Rotavirus was for many years the most common agent; although severe cases have decreased markedly with the spread of vaccination, norovirus and adenovirus are still frequently encountered. Bacterial causes are less common but usually more severe; salmonella, shigella, campylobacter and certain strains of E. coli head this group and are mostly transmitted through undercooked food, improperly stored meals or unsafe water. Parasites are responsible more often for prolonged and recurring diarrhoea. Non-infectious causes should not be overlooked either: antibiotic use can cause diarrhoea by disturbing the intestinal flora, and fruit juice and sugary drinks consumed in excess can draw water into the bowel and loosen the stool. Absorption problems such as food allergies, coeliac disease and lactose intolerance should also come to mind, particularly in prolonged cases. There is one more common situation that families find it useful to know: after an intestinal infection the inner surface of the bowel may be temporarily damaged and the child may have difficulty digesting milk for a few weeks; this temporary lactose intolerance resolves by itself as the bowel heals.

Recognising Fluid Loss

The real danger of diarrhoea in children is not the stool itself but the water and minerals lost along with it; the most important skill a family needs to learn is therefore to recognise the signs of fluid loss. In mild fluid loss the child is thirsty, the mouth is slightly dry and they are restless; at this stage the situation is easily corrected with fluids given by mouth. In moderate loss the amount of urine decreases, the number of wet nappies falls markedly in babies, tears decrease or are absent when crying, the mouth and tongue become dry, the eyes appear sunken and the fontanelle is depressed in babies. In severe fluid loss the child becomes drowsy and sleepy, the pulse quickens, breathing becomes rapid and shallow, the hands and feet turn cold, the skin takes on a pale or mottled appearance and urine stops altogether; this picture requires emergency intervention. Some children carry a higher risk of fluid loss: babies under six months, low birth weight babies, babies who stop feeding during illness, and those with many watery stools or repeated vomiting in the last twenty-four hours are in this group. As a practical method of monitoring, noting the number of wet nappies in babies and the interval between passing urine in older children allows a family to follow the situation objectively.

The Right Approach at Home

The basis of what is done at home for a child with diarrhoea is replacing the lost fluid in small amounts at frequent intervals. Oral rehydration solutions, available in ready-made sachets from pharmacies, are used for this; these mixtures contain water, salt and sugar in proportions that maximise absorption from the bowel. The solution must be prepared with the amount of clean water stated on the packet, must not be diluted by guesswork, and should be given in an amount appropriate to the child's age after every watery stool. If there is vomiting, large amounts will trigger further vomiting, so the fluid should be given with a spoon or a little at a time, every few minutes; with this method most children can take enough fluid despite vomiting. In breastfed babies, breastfeeding must never be stopped; on the contrary it should be made more frequent, since breast milk provides fluid, nourishment and protective factors alike. As for feeding, starving the child is a practice that has now been abandoned; as appetite returns, a normal diet should be resumed with easily digested foods such as rice, potato, banana, yoghurt, boiled chicken, fat-free soup and bread. Fatty and fried foods, spicy dishes, fruit juices, fizzy and sugary drinks can increase diarrhoea during this period and should be limited. If the physician considers it appropriate, zinc supplementation and certain probiotics that support the recovery of the bowel surface may be added to treatment; these are supports to be used when recommended, not started on one's own.

Common Mistakes

Foremost among the mistakes made with diarrhoea is giving the child anti-diarrhoeal medicine without a physician's advice. These medicines, which stop bowel movement, are not used in children; they can cause germs and toxins to remain in the bowel, lead to abdominal distension and make the condition worse. The second common mistake is starting leftover antibiotics from home or asking the physician for antibiotics; the great majority of diarrhoea in children is viral, antibiotics are of no benefit at all, and they may even prolong the diarrhoea by disturbing the flora. Starving the child or stopping breast milk in the belief that the bowel needs to rest is likewise a widespread and harmful practice; hunger delays repair of the bowel surface and prolongs recovery. Trying to meet the need for fluid with fizzy drinks, cola, ready-made fruit juices or heavily sweetened compotes increases the diarrhoea, because the high sugar they contain draws water into the bowel. Salt-and-sugar mixtures prepared at home by guesswork are also unreliable; when the proportions are wrong they can do more harm than good, so ready-made solutions should be preferred. Finally, waiting on the assumption that "it will pass anyway", without following how long the diarrhoea has lasted and how much urine is being passed, allows fluid loss to advance silently.

When Should a Doctor Be Consulted?

Most children with diarrhoea recover with observation at home; but some situations should be assessed by a paediatrician without delay. Diarrhoea appearing in babies under six months is always a priority because of the risk of rapid fluid loss; in this age group, recurrent episodes or a condition lasting more than twenty-four hours must be seen. Blood or heavy mucus in the stool, or the stool taking on a tarry colour, should also be investigated, as it suggests a bacterial agent or a different problem. Vomiting so frequent that the child can keep nothing down, inability to take fluids, appearing constantly sleepy or unresponsive, and complaining of severe and persistent abdominal pain are reasons for emergency assessment. When signs of fluid loss appear — dry mouth, absence of tears, sunken eyes and a marked decrease in urine output — one should not wait. High fever accompanying the illness, diarrhoea continuing beyond four days or lasting more than ten days, and vomiting continuing beyond two days also require a consultation. In children with a condition such as heart disease, kidney disease or diabetes, or with an immune problem, diarrhoea should be monitored under medical supervision from the outset. Depending on the picture, the physician may request stool examination and blood tests where necessary and may recommend admission for intravenous fluid treatment if fluid loss is advanced.

Preventing Transmission

Most of the agents that cause diarrhoea are transmitted by the faecal–oral route, that is through contaminated hands, surfaces, water and food; the basis of prevention is therefore hygiene. Hand washing breaks the weakest link in this chain: hands should be washed with soap for at least twenty to thirty seconds, including between the fingers, under the nails and the wrists, and this rule should be followed particularly after changing a nappy, after using the toilet and before preparing food. If there is a child with diarrhoea at home, the toilet, flush handle, taps, door handles and bathroom surfaces should be cleaned regularly, and the child's towel should be kept separate and not shared. Soiled clothing and bedding should be washed separately and at a high temperature. Food safety is the second important heading: meat and chicken should be cooked thoroughly, unpasteurised milk and dairy products should be avoided, cooked food should be refrigerated promptly and under suitable conditions, and vegetables and fruit eaten raw should be washed well. Water of unknown origin should not be drunk, and pools of uncertain hygiene should be avoided. For a return to nursery or school it is recommended that at least forty-eight hours have passed since the last episode of diarrhoea or vomiting; this period serves both the child's recovery and the prevention of transmission to other children. The oral rotavirus vaccine is one of the most effective methods of protection against severe diarrhoea in infancy, and its timing is planned by your physician.

Frequently Asked Questions

Can I give medicine to stop the diarrhoea? The medicines used in adults to slow bowel movement are not suitable for children and must never be given without a physician's advice. Although these medicines may appear to stop the diarrhoea, they can cause serious problems by keeping germs and toxins in the bowel. In children the aim of treatment is not to stop the passing of stool but to replace the fluid lost. Any supports to be used where necessary are determined by the physician.

Can a child with diarrhoea have milk and yoghurt? Breast milk must not be stopped under any circumstances; on the contrary it should be given more often. Yoghurt is well tolerated by most children and can readily take its place in the feeding plan. Some children may develop temporary lactose intolerance after an infection; if bloating, wind and watery stools become marked after milk, milk may be reduced temporarily. This resolves by itself as the bowel surface heals and is not a permanent problem.

Are cola and sugary drinks good for diarrhoea? No; contrary to popular belief these drinks can make diarrhoea worse. The high proportion of sugar they contain draws water into the bowel and makes the stool even more watery, and they do not replace the minerals lost. The same applies to ready-made fruit juices and heavily sweetened compotes. The need for fluid should be met primarily with oral rehydration solutions, water, ayran and fat-free soups.

My child is vomiting and cannot keep any fluid down; what should I do? When there is vomiting, large amounts given at once trigger further vomiting, so the method must be changed. Fluid should be given with a spoon or in very small sips every few minutes, and the amount increased as tolerance improves. With this approach most children can take enough fluid. If despite this they can keep nothing down, their urine decreases or they become drowsy, a healthcare facility should be attended without delay.

How long does diarrhoea normally last? Most viral diarrhoea resolves within three to seven days; vomiting usually subsides earlier, in the first day or two. A complete return to the normal bowel habit may take a week, and soft stools may continue during this period. In diarrhoea exceeding ten days, a different underlying cause should be investigated. Noting the duration and urine output provides the most useful information when consulting a physician.

This article has been prepared for general information purposes only and does not take the place of a medical examination. If your child has signs of fluid loss, bloody stools, persistent vomiting or prolonged diarrhoea, please attend our Paediatrics outpatient clinic for assessment, diagnosis and treatment.