Growth Problems & Obesity in Childhood

Question 1

What advantages and disadvantages are offered by breastfeeding?

Answer 1

WHO recommend exclusive breastfeeding in the initial six months of life.

• It is free
• great opportunity for mum and baby to bond
• overfeeding less common than bottle feeding
• contains antibodies to protect neonate against infection
• linked to lower neonatal infections, better cognitive development, lower risk of certain conditions, reduction in childdhood obesity and reduced risk of sudden infant death syndrome.
• may reduce risk of breast and ovarian cancer in the mother.
• issues with breastfeeding such as poor milk supply, difficulty latching, discomfort/pain can lead to inadequate nutrition for the baby
• more opportunity for partner to be involved in feeding using bottles.

SOME DIFFERENCES MAY BE DUE TO SOCIO-ECONOMIC BACKGROUND OR OTHER CONFOUNDING FACTORS.

Question 2

Approximately how much should babies be consuming?

Answer 2

On formula- babies should receive 150ml of milk per kg

Preterm or underweight babies may require more than this.

Initially this is split between feeds every 2-3 hours, then 4 hours and longer between feeding. Babies will eventually transition to feeding on demand when they are hungry. Volumes are increased as tolerated from the first day of life.

Question 3

How much weight loss is considered normal in the first few days of baby’s life?

Answer 3

It is acceptable for breast fed babies to lose up to 10% of their birth weight by day 5. 5% in bottle fed babies.

They should be back at their birth weight at day 10.

if they are losing more weight or do not bounce back to their birth wight by 2 weeks, they should be admitted into hospital and assessed for causes.

Most common causes of weight loss or not regaining weight is dehydration due to underfeeding. They may not look dehydrated but the most reliable sign in babies is weight loss.

Question 4

What is weaning and roughly when should it occur?

Answer 4

Refers to the gradual transition from milk to normal food. Weaning usually starts at around 6 months of age.

Should start with pureed foods that are easy to palate, swallow and digest- eg. pureed fruit and baby rice.

Over 6 months this will progress towards a healthy diet, resembling an older child- supplemented with milk and snacks to 1 year of age.

Question 5

What is important when assessing whether a child has growth problems?

Answer 5

It is important to look at their growth chart, are they maintaining their centile?

A child on the 9th centile who has always been on the 9th centile is much less worrying than a child who was on the 91st and is now on the 9th!

If a child is on the 50th centile she is exactly average for their age and sex.

Question 6

What are phases of growth?

Answer 6

Children will go through three phases of growth-

• first 2 years- rapid growth driven by nutritional factors
• from 2 years to puberty- steady slow growth
• during puberty- rapid growthspurt driven by sex hormones

Question 7

What are the causes of the rise in childhood obesity?

Answer 7

Results from consuming more calories than are expended through activity and growth.

Increasing access to readily available, affordable, hyper-palatable, high calorie foods has lead to overconsumption of calories.

There has also been a shift from playing outdoors to sedentary activities such as video gaming etc.

Question 8

How is a child defined as being overweight or obese?

Answer 8

BMI above the 85th centile is considered overweight and above the 95th is considered obese.

Obese children are often tall for their age and come from overweight families. In children who are short and overweight, consider endocrine investigations for underlying cause such as hypothyroidism. Pathological causes are rare.

Question 9

What are the effects of childhood obesity?

Answer 9

Biggest immediate effect is bullying.

Obese children are at higher risk of developing impaired glucose tolerance, type 2 diabetes, CVD, arthritis and some types of cancer.

The family must engage to address the issue or it will continue into adulthood and carry associated negative health implications of adult obesity.

Question 10

What is failure to thrive?

Answer 10

Refers to poor physical growth and development in a child.

Question 11

What is faltering growth?

Answer 11

Faltering growth is defined as fall in weight across-

• one or more centile spaces if their birthweight was below the 9th centile
• two or more centiles if between 9th and 91st
• three or more centiles if above the 91st

centile spaces are the gaps between two centile lines!

Question 12

What can cause failure to thrive?

Answer 12

Anything that leads to inadequate energy and nutrition. Causes may be categorised as follows-

• inadequate nutritional intake
• difficulty feeding
• malabsorption
• increased energy requirements
• inability to process nutrition

CAUSES OF INADEQUATE NUTRITIONAL INTAKE

• maternal malabsorption if breastfeeding
• iron deficiency anaemia
• family or parental problems
• neglect
• availability of food (poverty)

CAUSES OF DIFFICULTY FEEDING

• poor suck eg. cerebral palsy
• cleft lip or palate
• genetic conditions with abnormal facial structure
• pyloric stenosis

CAUSES OF MALABSORPTION

• cystic fibrosis
• coeliac disease
• cows milk intolerance
• chronic diarrhoea
• IBD

CAUSES OF INCREASED ENERGY REQUIREMENT

• hyperthyroidism
• chronic disease eg. congenital heart disease and cystic fibrosis
• malignancy
• chronic infections eg. HIV

INABILITY TO PROCESS NUTRIENTS PROPERLY

• inborn errors of metabolism
• type 1 diabetes

Question 13

How would you assess a child with failure to thrive?

Answer 13

Aim of assessment is to establish the cause!

History, examination and completing relevant investigations.

key areas for hx-

• pregnancy, birth, development
• social history
• feeding/eating history
• observe feeding
• mum’s physical and mental health
• parent-child interactions
• height, weight and BMI (if over 2) plot on growth chart
• calculate mid-parental height centile (height of mum + height of dad /2)

Question 14

What would suggest inadequate nutrition or a growth disorder?

Answer 14

• height more than 2 spaces below the mid-parental height centile
• BMI below the 2nd centile

Question 15

Which investigations are recommended in a child with faltering growth?

Answer 15

NICE guidelines recommend initially-

• urine dipstick, for UTI
• coeliac screen (anti-TTG or anti-EMA antibodies)

Further investigations are not usually needed if there are no other clinical concerns.

Focused investigations should be considered where there is suspected diagnosis such as CF or pyloric stenosis.

Question 16

How is a child with faltering growth managed?

Answer 16

depends on cause
may involve input from MDT
should have regular reviews to monitor growth- however parental concern is heightened with frequent review.

where there are breastfeeding difficulties, mothers should be supported through midwives, health visitors, peer groups and lactation consultants.

supplementation with formula will improve growth but may result in breastfeeds stopping. mothers should be encouraged to feed with breastmilk prior to bottle top ups and to express when not breastfeeding to allow lactation to continue.

where inadequate nutrition is the cause there are several options-

• regular structured mealtimes and snacks
• reduce milk consumption to improve appetite for other foods
• dietician review
• additional energy dense foods to boost calories
• nutritional supplement drinks

where other measures fail and there are serious concerns the MDT may consider enteral feeding- this must have well defined goals and a clear endpoint.

Question 17

How is short stature defined?

Answer 17

defined as height more than 2 standard deviations below the average for their age and sex (same as being below the 2nd centile)

Question 18

How is a child’s predicted height calculated?

Answer 18

A child’s predicted height can be calculated based on their parents height measured in cm.

Different formulas are used for girls and boys-

boys
(mother height+fathers height +14cm)/2

girls
(mothers height+fathers height-14cm)/2

Question 19

What are the causes of short stature?

Answer 19

Familial short stature
constitutional delay in growth and development
Malnutrition
Chronic disease such as coealiac, IBD or congenital heart disease
Endocrine disorders
Genetic conditions eg. Down’s
Skeletal dysplasia eg. achondroplasia

Question 20

What is constitutional delay in growth and puberty?

Answer 20

Considered a variation on normal development. Leads to short stature in childhood but normal height as an adult.

Puberty is delayed and the growth spurt during puberty lasts longer- they ultimately reach their predicted adult height.

A key feature of CDGP is delayed bone age. The age of a child can be estimated using x-ray images of the hand/wrist through assessment of the bone shapes and growth plates. Those with CDGP will have delayed bone age compared to peers of same age and sex.

Question 21

How is CDGP diagnosed?

Answer 21

Is based on suggestive history and exam supported by x-ray of the hand/wrist to assess bone age.

Question 22

How is CDGP managed?

Answer 22

Involves excluding other causes of a short stature and delayed puberty
Reassuring parents and the child and monitoring growth over time.

Question 23

What is considered normal puberty? How does puberty start in boys and girls?

Answer 23

Puberty starts age 8 – 14 in girls and 9 – 15 in boys. It takes about 4 years from start to finish. Girls have their pubertal growth spurt earlier in puberty than boys.

In girls, puberty starts with the development of breast buds, then pubic hair and finally starting menstrual periods about 2 years from the start of puberty.

In boys, puberty starts with enlargement of the testicles, then of the penis, gradual darkening of the scrotum, development of pubic hair and deepening of the voice.

Question 24

How can pubertal stage be determined based on sex characteristics?

Answer 24

The tanner scale can be used to determine the pubertal stage based on examination findings of sex characteristics.

Question 25

What is hypogonadism?

Answer 25

Hypogonadism refers to a lack of the sex hormones, oestrogen and testosterone, that normally rise prior to and during puberty. A lack of these hormones causes a delay in puberty. This is fundamentally due to one of two reasons:

Hypogonadotrophic hypogonadism: a deficiency of LH and FSH
Hypergonadotrophic hypogonadism: a lack of response to LH and FSH by the gonads (the testes and ovaries)

Question 26

What is hypogonadotropic hypogonadism?

Answer 26

Hypogonadotropic hypogonadism is where there is a deficiency of LH and FSH, leading to a deficiency of the sex hormones testosterone and oestrogen. LH and FSH are gonadotrophins. Since there are no gonadotrophins simulating the gonads, they do not respond by producing sex hormones (testosterone and oestrogen). Therefore, you get “hypogonadism” as a result of “hypogonadotropism”.

A deficiency of LH and FSH is the result of abnormal functioning of the hypothalamus or pituitary gland. This could be due to:

Previous damage to the hypothalamus or pituitary, for example by radiotherapy or surgery for previous cancer
Growth hormone deficiency
Hypothyroidism
Hyperprolactinaemia (high prolactin)
Serious chronic conditions can temporarily delay puberty (e.g. cystic fibrosis or inflammatory bowel disease)
Excessive exercise or dieting can delay the onset of menstruation in girls
Constitutional delay in growth and development is a temporary delay in growth and puberty without underlying physical pathology
Kallman syndrome

Question 27

What is hypergonadotropic hypogonadism?

Answer 27

Hypergonadotropic hypogonadism is where the gonads fail to respond to stimulation from the gonadotrophins (LH and FSH). There is no negative feedback from the sex hormones (testosterone and oestrogen), therefore the anterior pituitary produces increasing amounts of LH and FSH to try harder to stimulate the gonads. Therefore, you get high gonadotrophins (“hypergonadotrophic”) and low sex hormones (“hypogonadism”).

Hypergonadotrophic hypogonadism is the result of abnormal functioning of the gonads. This could be due to:

Previous damage to the gonads (e.g. testicular torsion, cancer or infections, such as mumps)
Congenital absence of the testes or ovaries
Kleinfelter’s Syndrome (XXY)
Turner’s Syndrome (XO)

Question 28

What is Kallman syndrome?

Answer 28

Kallman syndrome is a genetic condition causing hypogonadotrophic hypogonadism, resulting in failure to start puberty. It is associated with a reduced or absent sense of smell (anosmia).

Question 29

Which investigations can be done in those with delayed puberty?

Answer 29

The threshold for initiating investigations is when there is no evidence of pubertal changes in a girl aged 13 or a boy aged 14. The first step is to take a detailed history of their general health, development, family history, diet and lifestyle. An examination to assess height, weight, stage of pubertal development and features of underlying conditions. Investigation can also be considered when there is some evidence of puberty but no progression over 2 years.

Initial investigations can be used to look for underlying medical conditions:

Full blood count and ferritin for anaemia
U&E for chronic kidney disease
Anti-TTG or anti-EMA antibodies for coeliac disease
Hormonal blood tests can be used to look for hormonal abnormalities:

Early morning serum FSH and LH (the gonadotropins). These will be low in hypogonadotrophic hypogonadism and high in hypergonadotrophic hypogonadism.
Thyroid function tests
Growth hormone testing. Insulin-like growth factor I is often used as a screening test for GH deficiency.
Serum prolactin
Genetic testing with a microarray test can be used to look for underlying genetic conditions:

Kleinfelter’s syndrome (XXY)
Turner’s syndrome (XO)
Imaging can be useful:

Xray of the wrist to assess bone age and inform a diagnosis of constitutional delay
Pelvic ultrasound in girls to assess the ovaries and other pelvic organs
MRI of the brain to look for pituitary pathology and assess the olfactory bulbs in possible Kallman syndrome

Question 30

How is delayed puberty managed?

Answer 30

Management involves treating the underling condition where there is one. Patients with constitutional delay may only require reassurance and observation. Replacement sex hormones (oestrogen in girls and testosterone in boys) can be used to induce puberty under expert guidance.