Growth Flashcards
What are the 4 stages of growth?
- Fetal
- Infantile
- Childhood
- Pubertal growth spurt
What determines amount of growth in the fetal stage?
Uterine environment:
- Size of mother
- Placental nutrient supply
Which period of growth is the fastest?
Fetal stage
What determines the amount of growth in the infantile stage?
- Nutrition
- Health & happiness
- Thyroid function
What determines the amount of growth in the childhood phase?
- Growth hormone secretion @ the pituitary
- Nutrition
- Health & happiness
- Thyroid function
How do pubertal hormones work to boost and finalise growth?
Boost growth by causing the back to lengthen & boosting GH secretion.
They also cause fusion of the epiphyseal growth plate.
How can early puberty cause short stature?
Early fusion of the epiphyseal growth plate.
What would raise concerns when assessing the height of a child?
- Measurements below 0.4th centile or above 99th centile
- Markedly discrepant from weight
- Serial measurements crossing centile lines after the 1st year of life.
What is the definition of short stature?
Height less than second centile (however usually normal)
How can you identify growth failure before height falls below the 2nd centile?
Identifying height falling across centile lines on a height velocity chart.
How do you measure height velocity?
Two accurate* measurements of height ideally a year apart (but at least 6 months) to calculate height velocity in cm/year. Plotted on the midpoint in time on a height velocity chart.
*Tend not to be used outside specialist growth clinics because of the need for accurate measurements.
What should the height centile be compared to?
- Weight centile
- Estimate of the genetic expected genetic height
- Calculated as mean of parental height with adjustment for gender.
What are the causes of short stature?
- Familial
- Constitutional delay in growth & puberty
- Small for gestational age & extreme prematurity
- Chromosomal disorder/syndromes
- Nutritional/long-term illness
- Psychosocial (Emotional deprivation/neglect)
- Endrocrine
What is meant by constitutional delay in growth & puberty?
Presentation of short stature in teenage years because of a delay in the onset of puberty:
- Growth in childhood usually at lower limits of normal
- Bone age delayed
- Onset of secondary sexual development delayed
- Normal final height
- Family Hx
How can you manage children born small for gestational age or who were extremely premature when they haven’t caught up sufficiently by 4 years of age?
Growth hormone treatment
How do children typically present when short stature is due to nutritional/long-term illness?
Short & underweight
Why may a child have inadequate nutrition?
- Insufficient food
- Restricted diets
- Poor appetite due to illness
- Increased nutritional requirement due to raised metabolic rate
What chronic illnesses may present with short stature?
- Coeliac disease
- Usually presents in first 2 years of life but can present late with faltering growth.
- Crohn’s disease
- Chronic kidney disease
- Cystic fibrosis
- Congenital heart disease
What is faltering growth?
Inadequate rate of weight gain.
What are the endocrine causes of short stature?
- Hypothyroidism
- Growth hormone deficiency
- Corticosteroid excess (Cushing syndrome / Iatrogenic)
What proportions are described by skeletal dysplasia?
Legs > Back
What proportions are described by the term “storage disorders”?
Back > legs
Why does cystic fibrosis cause short stature?
- Malabsorption
- Recurrent infections
- Increased work of breathing
- Reduced appetite
How do you confirm disproportionate short stature?
- Sitting height = Base of spine to top of head
- Subischial leg length = Total height - Sitting height
- Radiographic skeletal survery
What investigations may be indicated in a patient with short stature?
- XR of non-dominant hand & wrist for bone age
- Bloods
- FBC, U&Es, CRP/ESR, Ca, Phos, Alkaline phos, TSH
- Karyotype
- Growth hormone provocation tests
- IGF-1
- 0900h cortisol & dexamethasone test
- MRI scan (if neuro signs & symptoms)
- Limited skeletal survey
How is GH deficiency managed?
