Faltering growth in children

Synonym: failure to thrive

What is faltering growth?

Faltering growth is a significant interruption in the expected rate of growth compared with other children of similar age and sex during early childhood. It is a descriptive term and an underlying cause must be considered.

Faltering growth usually applies to young children, especially babies rather than older children or teenagers.

Weight loss of up to 10% of birthweight is common in the early days of life, butbirth weight is usually regained before 3 weeks of age when feeding is established.¹ Faltering growth after the early days of life is characterised by a slower rate of weight gain than expected.

Definitions

• Weight faltering is defined as weight falling through centile spaces, low weight for height or no catch-up from a low birth weight.

• Growth faltering is defined as crossing down through length/height centile(s) as well as weight. A low height centile or height less than expected from parental heights.

Epidemiology

Infants commonly show some weight faltering in the first two years of life but it may also affect older children. Faltering growth (or failure to thrive) can affect patients of all ages, but it is most common in infants and younger children.² There is no gender or race predisposition, but it has been associated with increased deprivation, lower parental education level, and with other increased psychosocial stressors in the home environment.

The prevalence of faltering growth depends on the population studied and dignostic criteria used. In the United States, it may occur in up to 10% of children in primary care and in approximately 5% of children who are hospitalized.³ The rate of detection is thought to vary with the vigilance of individual clinicians involved.

The World Health Organization (WHO) has proposed growth standards, based on healthy, relatively affluent, breast-fed infants from six countries. These standards, along with UK birth and preterm growth data, have been incorporated into the UK-WHO growth charts. Studies that assessed the growth pattern of representative samples of European children compared with these new charts found that these children tended to gain weight more rapidly. Therefore, only about 0.5% of UK children will be below the 2nd centile at 12 months. See the separate Centile Charts and Assessing Growth article.

Assessing normality

When assessing growth in all children, both height and weight should be considered. Repeated measurements of height and weight showing changes of centiles on charts are much more important than a single measurement.

To diagnose weight and growth faltering, it is imperative to understand normal growth and variation. For example, it is normal for a baby to lose up to 10% of body weight in the first few days of life. This is rapidly regained but more slowly in breast-fed babies.

Premature babies

For premature babies a 'corrected age' should be used, based on time since birth minus degree of prematurity. Thus, a baby who was born 12 weeks previously at 32 weeks of gestation is treated as a four-week-old baby. Growth charts based on gestational age rather than chronological age are available for infants from 26 weeks of gestational age but they are synthesised from a relatively small number of infants with variable problems and so they should be treated with caution.⁴

A premature baby should have reached 'normality' for head circumference at around 18 months, for weight at about 24 months and for height at above 40 months. Thereafter, normal charts may be employed but some premature babies with very low birth weight do not catch up until they are 5 or 6 years old.

There are also specific reference charts for Down's syndrome and Turner syndrome.

Faltering growth symptoms

Diagnosing that abnormality exists is fundamental to this issue and is discussed in much more detail in the separate Centile Charts and Assessing Growth article. This article will focus instead upon the many causes of weight and growth faltering.

There are separate centile charts for boys and girls, as the former tend to be bigger.⁵ There may well be some racial differences too. Children of Indian race are often a little smaller than those of European origin and it is inappropriate to cause undue concern over a child who is obviously happy and well. Look at the parents. Tall parents have tall children and short parents have short children. Obesity is an acquired rather than hereditary condition, although there may be some genetic factors.

The genetic components of height and weight tend to become manifest between birth and 2 years of age. Hence, children of small parents may fall through the centile charts. The height and weight should be on roughly the same centiles and look at the height of the parents. Radiological bone age is also normal. About 25% of normal children will shift to a lower centile line in the first two years of life. If there are small parents and a healthy, happy child, there is no cause for concern .

History

Start by looking at the history of the pregnancy with regard to:

• Smoking.

• Alcohol consumption.

• Use of medications.

• Any illness during the pregnancy.

As a general rule, placental insufficiency will lead to a small-for-dates baby who emerges hungry and eager to feed.

• Examine infant feeding:
  

  • With bottle-fed babies it is easy to see exactly how much is taken at each feed.

  • With breast-feeding this is much harder without test feeding.

  • Note whether the child seems content with the feed, dissatisfied and craving more or uninterested.

• Ask about the frequency of wet nappies and dirty nappies.

• Ask about the nature of the stool:
  

  • Remember that it is highly variable in quality and quantity in small babies, especially if breast-fed.

  • Chronic diarrhoea will result in failure to gain weight.

• Ask about illness in the child. Meningitis, fits and cerebral palsy may all cause or indicate problems.

• Observe how the mother interacts with the child - note whether she is caring and concerned or cold and distant.

• Note whether there is any indication of developmental delay (such as delay in walking or delay in talking).

Examination¹

Look at the baby in respect of the following questions:

• Does this look a healthy, lively and active child?

• Are there any features suggestive of a syndrome such as Down's syndrome or Turner syndrome?

• Does the child look well-nourished or starved?

• Are there any other obvious features such as:
  

  • Cyanosis?

  • Tachypnoea?

  • Jaundice?

• When picked up, does muscular tone feel normal and does the baby respond as if used to affection?

• Is the child alert and responsive?

Plot height, weight and head circumference on a chart. If possible, plot earlier readings too, as trends or falling through the centiles are much more important than isolated readings.

Note pulse rate and respiratory rate. Possibly blood pressure and even arterial blood gases may be required. Blood gas analysis may prevent excessive diagnosis of renal tubular acidosis .

Other physical signs of failure to thrive may include:

• Oedema.

• Hepatomegaly.

• Rash or skin changes.

• Hair colour and texture abnormalities.

• Signs of vitamin deficiency.

Marasmus is pure calorie malnutrition but it can mimic dehydration. Features of dehydration include:

• Decreased skin turgor.

• Sunken anterior fontanelle.

• Dry mucous membranes.

• Absence of tears.

• Acutely ill appearance.

Differential diagnosis²

The range of causes of faltering growth is very wide and more than one may be applicable.

Prenatal causes of failure to thrive include:

• Prematurity with complications.

• Maternal malnutrition.

• Toxic exposure in utero, including alcohol, smoking, medications, infections.

• Intrauterine growth restriction (IUGR).

• Chromosomal abnormalities.

IUGR often produces a small but hungry and eager baby. However, a combination of preterm and small-for-dates is more likely to cause difficulties.

Toxins in utero may include tobacco, drugs of abuse (especially amfetamines and cocaine) and alcohol. Fetal alcohol syndrome may occur or the incomplete fetal alcohol effects. Infection in utero may include rubella, toxoplasmosis and cytomegalovirus.

Postnatal causes include lack of adequate intake of nutrition:

• Lack of appetite may occur with iron-deficiency anaemia, cental nervous system (CNS) pathology and chronic infection.

• Inability to suck or swallow, especially with CNS or muscular disorders.

• Vomiting due to CNS or metabolic diseases, obstruction or renal disorders.

• Gastro-oesophageal reflux and oesophagitis.

Physical problems of feeding may occur with cleft palate, hypotonia, micrognathia and Prader-Willi syndrome.

Poor absorption or metabolism of nutrients occurs with:

• Gastrointestinal disorders including cystic fibrosis, coeliac disease and chronic diarrhoea.

• Chronic kidney disease or renal tubular acidosis.

• Endocrine abnormalities, including hypothyroidism, diabetes mellitus, hypopituitarism.

• Inborn errors of metabolism.

• Chronic infection, including congenital HIV, tuberculosis, parasites.

Increased metabolic demand occurs with:

• Hyperthyroidism.

• Chronic heart or respiratory disease such as heart failure, asthma or broncho-pulmonary dysplasia.

• Chronic kidney disease.

• Malignancy.

Non-organic or 'functional' causes of faltering growth may include:

• Feeding difficulties.⁶

• Lack of preparation for parenting.

• Family dysfunction (eg, divorce, spouse abuse, chaotic family style).

• A difficult child.

• Child neglect (there may be puerperal depression).

• Emotional deprivation syndrome.⁷

• The mother may have an eating disorder but more often they tend to over-feed the rest of the family.

• Fabricated or induced illness by carers (FII) - formerly known as Münchhausen's syndrome by proxy.

Investigations⁸

Organic disease as a cause of faltering growth is rare in otherwise asymptomatic children but it is reasonable to rule out organic disease if dietary and behavioural interventions are unsuccessful .

Investigations are usually guided by history and examination. Routine tests may include:

• FBC.

• Urinalysis.

• Urine culture.

• U&E and creatinine.

• LFTs, including total protein and albumin.

• Coeliac screen.

• Prealbumin which may be used as a nutritional marker.

The following tests are not usually routine but may be indicated by history and examination:

• Testing for HIV infection.

• Sweat chloride test.

• TFTs.

• Stool studies for parasites or malabsorption.

• Immunoglobulins.

• Purified protein derivative (PPD) skin test (for tuberculosis).

• Radiological studies (bone age may be helpful to distinguish genetic short stature from constitutional delay of growth).

Special tests may be used for coeliac disease or to detect growth hormone deficiency.

Associated diseases

Look for problems in the mother as well as problems in the child. Puerperal depression may present with the child failing to thrive.

Faltering growth management⁸

Many children with faltering growth do not have any specific underlying cause other than undernutrition relative to a child's specific energy requirements. Therefore, most children can be managed by advice and support given to the family by a health visitor and, if necessary, an assessment and advice from a dietician. Possible strategies for increasing energy intake in children aged over 9 months include :

• Dietary:
  

  • Three meals and two snacks each day.

  • Increase the number and variety of foods offered.

  • Increase energy density of usual foods, such as adding cheese, margarine or cream.

  • Limit milk intake to 500 mL per day.

  • Avoid excessive intake of fruit juice and squash.

• Behavioural:
  

  • Offer meals at regular times with other family members.

  • Praise when food is eaten but ignore when not.

  • Limit a meal's time to 30 minutes.

  • Parents should eat at the same time as the child.

  • Mealtime conflict should be avoided.

  • The child should never be force-fed.

See also separate Infant Feeding and Childhood Nutrition articles.

Management will otherwise depend upon the underlying cause of faltering growth.⁹

• With syndromes such as Turner syndrome or Down's syndrome, it may be that use of the correct charts shows that growth is as expected.

• Physical illness such as cyanotic congenital heart disease, cystic fibrosis or coeliac disease needs treating accordingly.

• High-calorie feeding may be required but this needs specialist help, otherwise overloading the gut causes diarrhoea and is counterproductive.

• A health visitor can provide plenty of help and advice. It may be necessary to remove the baby, especially in FII; however, this should not be done without considerable thought and attempts to rectify the situation.

• If improvement in the community is inadequate, admission to hospital may permit more intense observation and support. If the child thrives under these conditions, it is highly suggestive of poor parenting skills.

• Puerperal depression may need to be treated. Support and supervision are needed in the meantime.

• The baby may need to be put on the 'at risk' register with multidisciplinary input until such time as it is deemed safe to remove the name.

Referral

Dietician

Many cases of faltering growth/weight will be due to poor feeding. Early input from a paediatric dietician may be very useful.

Paediatrician¹

• Thorough evaluation is always required for any child with a height or weight below the 0.4^th centile or for a sustained fall through 2 centiles.

• Specialist evaluation should be considered if the weight or height is below the 2^nd centile.

• Referral to a paediatrician is mainly to reassess the growth data, undertake investigations to exclude organic pathology and reinforce dietary advice.

• Inpatient monitoring is not advisable, except in very extreme circumstances.

Social work

• Cases where the family has major social problems, such as drug or alcohol abuse, or where direct evidence suggests abuse or neglect.

• Families may lack adequate resources to ensure that a child is well nourished, and involvement of social services may enable families to access appropriate support.

Psychology

Indications include pronounced food refusal or very anxious, stressful mealtimes.

Prognosis⁸

• If faltering growth is due to an underlying condition the prognosis will be depend on the specific condition and its treatment.

• Early identification and treatment of all cases of faltering growth may improve prognosis and prevent long-term complications.

• Long-term outcome of growth faltering in early age is a reduction in IQ of about three-four points, which is maintained into adulthood.¹⁰

Faltering growth prevention

• Good antenatal care and avoidance of toxins such as illicit drugs, tobacco and alcohol in pregnancy will reduce the risk.

• Parenting classes should lead to a better understanding of the needs of the baby. Nowadays fathers are often involved too and this is to be welcomed.

• An astute midwife or health visitor should detect problems before they become serious.