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Unit 1 - The Epidemiology and Etiology of Diarrhoea
Unit 2 - Pathopysiology of Watery Diarrhoea: Dehydration and Rehydration
Unit 3 - Assessing the Diarrhoea Patient
Unit 4 - Treatment of Diarrhoea at Home
Unit 5 - Treatment of Dehydrated Patients
Unit 6 - Dysentery, Persistent Diarrhoea, and Diarrhoea Associated with Other Illnesses
Unit 7 - Diarrhoea and Nutrition
Unit 8 - Prevention of Diarrhoea

Unit 3 - Assessing the Diarrhoea Patient
Medical Education: Teaching Medical Students about Diarrhoeal Diseases

World Health Organization 1992

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Ask, look, and feel for signs of dehydration
Determine the degree of dehydration and select a Treatment Plan:
Column C - Severe dehydration
Column B - Some dehydration
Column A - No signs of dehydration
Weigh the child

Persistent diarrhoea
Feeding history
Physical findings
Vitamin A deficiency
Measles vaccination status




Every child brought to a health facility because of diarrhoea should be carefully assessed before his or her treatment is planned. In most cases the information gained by spending a few minutes asking for details of the illness, and observing and examining the child for specific signs (e.g., of dehydration or undernutrition), is sufficient to make a diagnosis and develop a plan for treatment.

The clinical assessment consists of taking a brief history and examining the child. Its objectives are to:

  • detect dehydration, if present, and determine the degree of severity;
  • diagnose dysentery, if present;
  • diagnose persistent diarrhoea, if present;
  • evaluate feeding practices and determine the child's nutritional status, especially to detect severe undernutrition;
  • diagnose any concurrent illness; and
  • determine the child's immunization history, especially as regards immunization for measles.
  • Depending upon what is found, the clinical assessment should lead directly to:
  • a plan for treating or preventing dehydration;
  • a plan for treating dysentery;
  • a plan for treating persistent diarrhoea;
  • recommendations for feeding during and after diarrhoea;
  • a plan for managing any concurrent illness;
  • recommendations regarding measles immunization;
  • a plan for follow-up.
  • This unit explains how the clinical assessment should be performed and interpreted, in order to ensure that the above objectives are achieved. Treatment plans for dehydration and other problems associated with diarrhoea, and for the maintenance of nutrition in patients with diarrhoea are considered in Units 4-7.


    The WHO chart "Management of the Patient with Diarrhoea" is designed to help guide the evaluation and treatment of patients with diarrhoea. It summarizes the questions to be asked and the signs to be observed in a manner that helps the doctor or health worker to remember the most important points and to follow a standard pattern in patient evaluation. It also shows how to use the results of the patient evaluation to determine the most appropriate treatment. This approach should be used for all children who are seen at a treatment facility with a complaint of loose or watery stools or loose stools with blood.

    The top part of the chart shows how to assess patients for dehydration (Figure 3.1), and how to assess and manage other important problems that diarrhoea patients may have (Figure 6.1, Unit 6). The clinical features described in these figures are the ones that are most important and can be most reliably assessed by health workers at all levels. These and additional features with which doctors should be familiar are considered below.

    Figure 3.1 How to assess patients for dehydration

    Information on the history, examination, and treatment of each patient should be summarized on a "Patient Record Form". An example of such a form is given in Annex 1. Modified versions of this form may be used, but they should include at least:

  • a brief history of the diarrhoeal episode, including its duration and whether blood has been seen in the faeces;
  • the child's pre-illness feeding pattern;
  • the child's immunization history, especially as regards measles;
  • important findings during examination of the child, especially signs of dehydration or undernutrition, and the child's weight;
  • a summary of fluid intake and output, and the evolution of clinical findings in patients given rehydration therapy at the health facility;
  • a description of food given at the health facility;
  • a description of any medicines given at the health facility; and
  • recommendations for treatment, feeding, and follow-up after the child leaves the health facility.
  • When the form is completed promptly and accurately, it provides a valuable record of the child's progress during treatment at the health facility. It also helps to remind the health worker of all the steps that should be taken in the evaluation and management of the patient. Completed forms should be kept at the health facility and reviewed regularly to identify areas in which case management practices could be improved. Forms completed by students should be verified by a supervising physician; this can serve as an important means of evaluating the student's skills in diagnosis and case management.


    Patients should first be evaluated for dehydration and then for other problems associated with diarrhoea. Usually, both steps are completed before treatment is given. However, when a child is severely dehydrated, taking a complete history and doing a thorough examination must be deferred so that treatment can be started without delay. Seeing a stuporous child, confirming that the condition began with diarrhoea and vomiting, and quickly confirming that the skin turgor is very poor gives sufficient information to indicate that the patient has severe dehydration and requires an intravenous drip at once. When the drip is running well, the history and physical examination should be completed.

    Ask, look, and feel for signs of dehydration

    The detection of dehydration is based entirely on signs observed when the child is examined. Nevertheless, certain features of the history can help to identify children with diarrhoea who are at increased risk of being dehydrated. These include a history of vomiting, fever, and the passage of six or more diarrhoeal stools in the past 24 hours. When more than one of these features is present, the risk of dehydration is increased. It is also greater when fluids or water have been restricted or could not be given because of vomiting, and may be decreased when breast milk, ORS solution, recommended home fluids, or water have been given liberally during the illness.

    The signs to be evaluated are as follows:

    • Condition and behaviour. Carefully observe the child's general condition and behaviour. Does the child appear to be:
      • well, alert?
      • restless, irritable? or
      • floppy (listless), lethargic, or unconscious?

      Note: it is sometimes difficult to determine whether a child is abnormally lethargic, or just sleepy. This can often be decided by asking the mother whether the child is lethargic or only sleepy.

    • Eyes. Are the child's eyes:
      • normal?
      • sunken? or
      • very sunken and dry?
      Note that some children have eyes that are normally slightly sunken. It is often helpful to ask the mother whether her child's eyes are normal or more sunken than usual.
    • Tears. Does the child have tears when he cries vigorously?
    • Mouth and tongue. Are these:
      • wet?
      • dry? or
      • very dry?
      This can be assessed by feeling the tongue and inside the child's mouth with a clean, dry finger. Note that this sign can be affected by events other than dehydration. The mouth and tongue will be moist if the child has been drinking or has recently vomited; they will be dry if the child is breathing through the mouth.
    • Thirst. Offer the child some water in a cup or from a spoon and observe whether the child:
      • drinks normally, accepts the water without particular interest, or refuses to drink;
      • drinks eagerly, grasps for the cup or spoon, obviously wants to drink; or
      • is unable to drink or drinks poorly, because she/he is very lethargic or semi-conscious.
    • Skin pinch (skin turgor). When the skin of the abdomen or thigh is pinched and released, does the fold flatten and disappear:
      • immediately?
      • slowly? or
      • very slowly (i.e., taking more than 2 seconds)?
      This sign is usually very helpful, but obese children may fail to show diminished skin turgor even when dehydrated, owing to the layer of fat under their skin, and skin turgor may appear poor in children with marasmus even when there is no dehydration (see Unit 7).
    Additional signs that are not listed in Figure 3.1 but can also be of help in assessing hydration include:
  • Anterior fontanelle. In infants with some dehydration te anterior fontanelle is more sunken than usual; when dehydration is severe, it is very sunken.
  • Arms and legs. The skin of the lower parts of the arms and legs is normally warm and dry; the colour of the nail beds is normally pink. When dehydration is severe and there is hypovolaemic shock, the skin becomes cool and moist, and the nail beds may be cyanosed.
  • Pulse. As dehydration increases, the radial pulse and femoral pulse become more rapid. When dehydration is severe, the radial pulse becomes very rapid and weak. When there is hypovolaemic shock, it may disappear completely. The femoral pulse, however, remains palpable.
  • Breathing. The rate of breathing is increased in children with severe dehydration, due in part to their base-deficit acidosis. The absence of cough and chest indrawing helps to differentiate these children from children with pneumonia.
  • The assessment of hydration status is difficult in children with severe undernutrition because many of the signs described above are altered by the state of undernutrition. This is especially true for signs related to the child's general condition or behaviour, sunken eyes, absence of tears and diminished skin turgor. This topic is considered in greater detail in Unit 7.

    Determine the degree of dehydration and select a Treatment Plan

    After a patient with diarrhoea has been examined, the findings should be reviewed to determine the degree of dehydration (if any) and the appropriate Treatment Plan should be selected.

    The signs that indicate dehydration are shown in Figure 3.1, where they are organized into three columns (A, B, and C) according to the degree of severity. During the examination of the patient, each sign listed on the left of the figure should be evaluated and a circle placed around the descriptive term in column A, B, or C that best describes that sign in the patient. Signs that are most valuable in assessing dehydration, termed "key signs", are marked with asterisks (*) and shown in heavy print. Two or more circled signs in one column, including at least one key sign, means that the patient falls in that category of dehydration and requires the corresponding Treatment Plan. If signs are noted in more than one column, as often occurs, the category of dehydration is the one farthest to the right (among columns A, B, and C) in which two items, including at least one key sign, are circled.

    Column C - Severe dehydration

    Look first at column C. If two or more signs are circled in that column, including at least one key sign, the patient has severe dehydration.

    Patients with severe dehydration have a fluid deficit equalling more than 10% of their body weight. They are usually lethargic, stuporous or even comatose. The eyes are deeply sunken and without tears; the mouth and tongue are very dry, and breathing is rapid and deep. Patients who are awake are very thirsty; however, when there is stupor, the patient may drink poorly. Patients who are unconscious are unable to drink. A skin pinch retracts very slowly (more than 2 seconds). The femoral pulse is very rapid and the radial pulse is either very rapid and feeble or undetectable. The fontanelle in infants is very sunken. The patient may have passed no urine for six hours, or longer. When there is hypovolaemic shock, the systolic blood pressure taken in the arm is low or undetectable, the arms and legs are cool and moist, and the nail beds may be cyanosed.

    Severe dehydration requires urgent treatment, usually with IV fluids, following Treatment Plan C (see Unit 5).

    Column B - Some dehydration

    If severe dehydration is not present, look next at column B. If two or more signs listed in that column are circled, including at least one key sign, the patient has some dehydration. Note that patients may have signs in both columns B and C. If the signs in column C are not sufficient to diagnose severe dehydration, they should be counted as belonging to column B.

    Patients with some dehydration have a fluid deficit equalling 5-10% of their body weight. This category includes both "mild" and "moderate" dehydration, which are descriptive terms used in many textbooks:

  • "mild" dehydration (5-6% loss of body weight) is manifested mostly by increased thirst and restlessness. Skin turgor may be slightly decreased. Other signs associated with dehydration are not usually present.
  • "moderate" dehydration (7-10% loss of body weight) causes children to be restless, "fussy", or irritable. The eyes are somewhat sunken and the mouth and tongue are dry. There is increased thirst: older patients ask for water and young children drink eagerly when offered fluid from a cup or spoon. A skin pinch flattens slowly. The radial pulse is detectable, but rapid, and the fontanelle in infants is somewhat sunken.
  • Patients with some dehydration should be treated with ORS solution given by mouth, following Treatment Plan B (see Unit 5).

    Column A - No signs of dehydration

    If neither severe dehydration nor some dehydration is present, conclude that the patient has no signs of dehydration.

    Patients with diarrhoea but no signs of dehydration usually have a fluid deficit, but it equals less than 5% of their weight. Although they lack distinct signs of dehydration, they should be given more fluid than usual to prevent signs of dehydration from developing.

    Patients with no signs of dehydration should be treated at home, following Treatment Plan A (see Unit 4).

    Weigh the child

    Patients who are found to have some dehydration or severe dehydration should be weighed, if an accurate scale is available; children should be weighed unclothed. Weight is important for determining the amount of oral or intravenous fluid to be given in Treatment Plans B and C (see Unit 5). If no scale is available, weight should be estimated on the basis of the child's age or length (see Figure 5.1, Unit 5, and Annex 2), and treatment should be given without delay.

    The weight taken when a child is dehydrated should not be recorded on a growth chart, as it will be lower than normal owing to dehydration. Instead, the child should be reweighed after rehydration has been completed and that weight should be recorded on the chart. If possible, children with no signs of dehydration should also be weighed and the results recorded on a growth chart.


    After the patient has been evaluated for dehydration, other problems associated with diarrhoea should be considered. The assessment for other problems is summarized in Figure 6.1 in Unit 6 and discussed below.


    The health worker should ask whether the diarrhoea stools have contained any blood. If possible, a fresh stool specimen should also be observed for visible blood. If bloody diarrhoea is present, the patient should be considered to have dysentery and treated as described in Unit 6. If dehydration is present with the dysentery, it should also be treated immediately.

    Persistent diarrhoea

    The health worker should ask when the present episode of diarrhoea began. Episodes that have lasted at least 14 days should be considered to be persistent diarrhoea and treatment should follow the guidelines in Unit 6. Sometimes it is difficult to determine whether a child has persistent diarrhoea or is having sequential episodes of acute diarrhoea. Patients with persistent diarrhoea usually have loose stools every day, although the number per day may vary considerably. Sometimes, however, the child may have normal stools for one or two days after which diarrhoea resumes. If the period of normal (formed) stools does not exceed two days, the illness should be considered a single diarrhoeal episode. However, if the period of normal stools is longer than two days, any subsequent diarrhoea should be considered to be a new episode.


    A brief nutritional assessment should be carried out for each child with diarrhoea to identify those with nutritional problems and to obtain the information needed to make dietary recommendations. This assessment should include the recent feeding history and an examination to determine whether the child is adequately nourished or undernourished. Additionally, in areas where vitamin A deficiency is a public health problem, evidence of such deficiency should be sought. These steps are considered below.

    Feeding history

    The feeding history should consider both the child's usual (pre-illness) diet and the feeding pattern during the current episode of diarrhoea. The following points should be considered:

    Pre-illness feeding

    • Breast-feeding:
      • Is the child breast-feeding?
      • How frequently is breast milk given?
      • If less than 4-6 months of age, are any other liquids or food given?
      • If no longer breast-feeding, when was it stopped?
    • Animal milk or infant formula:
      • When was animal milk or formula started?
        • What type of milk is used and how is it prepared? For powdered milk or formula: is boiled water used? Is the formula correctly diluted?
      • Is the milk given in a feeding bottle, or by cup and spoon?
      • How much milk is given and how often?
    • Weaning foods (for children aged 4-6 months or older):
      • At what age were soft foods started?
      • What foods are given and how are they prepared?
        • Are food mixtures used? Do these contain vegetables, pulses, oil, fruit, eggs, or meat?
      • Are the foods liquid, soft, or solid?
      • How much food is given and how frequently?
      • Is the child given food from the family pot?

    Feeding during diarrhoea:

    • Breast-feeding:
      • Is breast milk given more often, as usual, or less often?
      • Does the child breast-feed well?
    • Animal milk or infant formula:
      • Has this been continued?
      • Has the amount given or the method of preparation changed, e.g., has the milk or formula been diluted?
    • Other fluids:
      • Has the child been given water, tea, juice, or other drinks?
      • How much has been given and how often?
    • Weaning foods:
      • Have these been continued?
      • How frequently has food been offered?
      • What types of food (and how much food) has the child accepted?
    • Mother's beliefs about feeding during diarrhoea:
      • What does the mother believe about giving breast milk, animal milk or formula, other fluids or foods during diarrhoea?
      • Which fluids or foods does she consider acceptable and which unacceptable during diarrhoea?

    Physical findings

    First, determine whether there is obvious severe protein-calorie undernutrition. This may have the features of marasmus, kwashiorkor, or both (see Figure 3.2).

    • Signs of marasmus include:
      • "old man's face";
      • extreme thinness, "skin and bones" appearance;
      • very thin extremities, distended abdomen;
      • absence of subcutaneous fat; the skin is very thin;
      • fretful, irritable behaviour.
    • Signs of kwashiorkor include:
      • oedema; ) essential
      • miserable, apathetic, listless behaviour; ) features
      • thin hair with reddish discolouration; )
      • flaking, dry skin; ) possible
      • enlarged liver. ) features

    Then, determine whether there is a less serious degree of undernutrition. This may not be possible in all settings, but should be done where conditions permit. The following examinations may be performed:

    • Weight-for-age. This is the simplest measure of nutritional status; however, it does not distinguish between past nutritional damage (i.e., stunting, which does not respond to increased feeding) and recent weight loss (i.e., wasting, for which increased feeding is important). Weight-for-age is most valuable when recorded on a growth chart and used to monitor growth over time; a series of points over several months shows whether or not the growth pattern is satisfactory (see Annex 3). Young children whose weight-for-age is below 70% of the standard, or whose weight is not increasing or is decreasing over time, should receive special nutritional advice and careful follow-up (see Unit 7).
    • Mid-upper arm circumference. This test involves measurement of the upper arm circumference using a standard tape (see Annex 4). It is simple to perform (a weighing scale is not required) and valuable as a screening test for undernutrition. However, it is not useful for monitoring growth over time.
    • Weight-for-height/length. Low height-for-age identifies children with stunting, but does not reveal whether their nutritional damage occurred recently or much earlier; this distinction is important because only those with recent undernutrition will benefit from nutritional therapy. A low weight-for-height ratio is valuable because it detects children with recent weight loss (wasting); however, two accurate measurements are required (i.e., weight and height/length). Unfortunately, height or length are more difficult to measure accurately than weight.
    Each of the above measurements should be interpreted using standard charts or tables. These may be either national or international standards. If the latter are used, national guidelines must be followed for their interpretation in the local setting.

    Vitamin A deficiency

  • Night blindness. Ask the mother if her child is able to see normally at night. Children with night blindness do not move about normally in the dark and may be unable to find their food or toys. Night blindness is difficult to recognize in children who are not yet old enough to walk.
  • Bitot's spots. These are dry, grey-white, foamy-appearing areas, triangular in shape, located in the temporal part of the scleral conjunctivae. Usually both eyes are affected.
  • Corneal xervis and ulceration. There are areas of the cornea that are roughened or ulcerated.
  • Children who have night blindness, Bitot's spots or Corneal xervis/ ulceration should be treated immediately with therapeutic doses of vitamin A (see Unit 7).


    The mother should be asked whether her child has had fever during the past five days. The temperature should also be measured (if possible, rectally). If rectal thermometers are available and can be disinfected after use, they are preferred. Otherwise, the temperature should be measured in the axilla (armpit). Any child with a history of recent fever or with a temperature of 38 C or greater should be managed as described in Unit 6. Such children should also be carefully checked for signs or symptoms of another infection, e.g., pneumonia.

    Measles vaccination status

    The mother should be asked whether her child has already received measles vaccine. The child's immunization record should also be consulted, if it is available. Children between 9 months and 2 years of age who have not previously been immunized should receive measles vaccine. The best time to give the vaccine is during the child's current visit to the treatment facility.


    1. Which of the following are not signs of severe dehydration:

    1. The skin pinch goes back slowly (within 2 seconds)
    2. The child is very lethargic
    3. The child is unable to drink
    4. The eyes are slightly sunken
    5. The mouth and tongue are very dry
    2. Marina, aged 2 years, is brought to you because she has had diarrhoea for three days. When you examine her you note that she is irritable and fussy and that her skin pinch goes back rather slowly. Other findings most consistent with her degree of dehydration would be:
    1. Normal eyes, tears are present when she cries, the mouth and tongue are moist
    2. The eyes are very sunken, tears are absent when she cries, and she is unable to drink
    3. The eyes are somewhat sunken, she drinks water eagerly from a cup, the mouth and tongue are rather dry
    4. She has a fever (38.5oC), her stool contains some blood, she is not especially interested in drinking water
    3. A mother brings her 2-year-old daughter, Asita, to you because she has had diarrhoea for two days. When you examine her you note that she is irritable and fussy, her eyes are not sunken, she has tears when she cries, her mouth is somewhat dry, and she takes water eagerly from a cup. Her skin pinch goes back rather slowly. Asita does not appear to be undernourished. Based on these findings, what conclusions would you draw about Asita's condition and how she should be treated? (There may be more than one correct answer.)
    1. Asita has severe dehydration
    2. Asita has no signs of dehydration
    3. Asita has some dehydration
    4. Asita should be treated according to Treatment Plan A
    5. More information is needed to determine how Asita should be treated for dehydration
    4. Bantu, aged 14 months, is brought to the health centre because of diarrhoea, which began three days ago. At first the stools were only loose, but yesterday his mother saw blood in them. The mother believes Bantu has a fever. He has also vomited two or three times. When you examine Bantu you note that he is alert, but irritable and restless. His eyes are not sunken, he has tears when he cries, his mouth is moist (but he has vomited recently), he will drink some water, but not with much interest. His skin pinch goes back quickly. His temperature is 39 C. Which of the following statements is (are) correct? (There may be more than one correct answer.)
    1. Bantu has some dehydration
    2. Bantu should be treated for dysentery
    3. Bantu should be treated according to Treatment Plan B
    4. Bantu should be examined for possible infection outside the intestinal tract, e.g., pneumonia
    5. Bantu has no signs of dehydration
    5. Which of the following should be done after an 11-month-old child with diarrhoea has been assessed for possible dehydration? (There may be more than one correct answer.)
    1. Ask whether there has been any blood in the stool
    2. Ask how long the diarrhoea has lasted
    3. Examine the child for signs of severe undernutrition
    4. Determine the child's temperature
    5. Determine whether the child has received measles vaccine (and other recommended immunizations)


    1. A, D. 2. C. The signs are those of some dehydration. 3. C. The signs of some dehydration are: irritable, fussy behaviour; taking water eagerly from a cup; and slightly decreased skin turgor. These are all key signs and are sufficient to make the diagnosis of some dehydration. The treatment should follow Treatment Plan B. 4. B, D, E. Bantu has only one of the signs in Column B (irritable, restless behaviour); the rest are in Column A. Therefore, he has no signs of dehydration. As the stool contains blood he should be tested for dysentery. Because he has fever, a search should be made for evidence of an infection outside the intestinal tract. Pneumonia is an important possibility, especially if he is coughing and breathing rapidly. 5. A, B, C, D, E.

    updated: 7 June, 2017