Revision - Development Flashcards
What 2 cancers is breastfeeding protective against?
1) ovarian
2) breast
On formula feed, how much milk per kg of body weight should babies receive?
150ml/kg
What is the most common cause of excessive weight loss or not regaining weight in the neonatal period?
Dehydration due to underfeeding
What is the most reliable sign of dehydration in babies?
Sunken fontanelles
What 3 measures are taken on a growth chart?
1) height
2) weight
3) head circumference
Children go through three phases of growth.
What are they?
Infancy: birth to 2y
Childhood: 2y to 11y
Puberty: 11y to 18y
In infancy, what are the 2 major drivers of growth?
1) insulin
2) nutrition
In childhood, what are the 2 main drivers of growth?
1) GH
2) thyroxine
In puberty, what are the 2 main drivers of growth?
1) GH
2) sex steroids
Centiles for overweight vs obese on growth charts?
BMI >85th centile: overweight
BMI >95th centile: obese
How often is growth monitored in the first 2 years of life?
0-1y –> should have at least 5 recordings
1-2y –> should have at least 3 recordings
How often is growth monitored in children aged >2 y/o?
Annual
What growth chart should be used for pre-term infants born <32 weeks gestation?
Neonatal and infant close monitoring (NICM) chart
What growth chart should be used for pre-term infants born 32-27 weeks gestation?
lot all measurements in the preterm section until 42 weeks gestation.
Then plot on the 0-1-year chart using gestational correction.
What is gestational correction?
Plot measurements at the child’s actual age, then draw a line back the number of weeks the infant was preterm.
Mark the spot with an arrow: this is child’s gestationally corrected centile.
Up until what age should gestational correction on growth charts be continued for in preterms?
Up to 1 y/o
A sustained drop in how many centiles is unusual and should be investigated?
A sustained drop across 2 or more centiles
What is Tanner stage 1 for girls?
Pre-pubertal
How is BMI calculated?
Weight (kg) / height (m)2
What 2 investigations are indicated if faltering growth is suspected?
1) urine dipstick for UTI
2) anti-TTG & anti-EMA for coeliac
Define short stature
Short stature is defined as a height more than 2 standard deviations below the average for their age and sex. This is the same as being below the 2nd centile.
What investigation should you order in kids with short stature?
XR –> delayed bone age is a key feature of constitutional delay in growth and puberty (CDGP) i.e. a normal variation
What testicular volume indicate the onset of puberty?
> 4ml
Define thelarche
First stage of breast development
What can precocious puberty be classified into?
1) Gonadotrophin dependent (‘true’)
2) Gonadotrophin independent (‘false’, ‘pseudo’)
What stage of Tanner Stages of Sexual Development does menarche usually coincide with?
3
What is gonadotrophin dependent (‘central’, ‘true’) precocious puberty due to?
Premature activation of the hypothalamic-pituitary-gonadal axis.
FSH and LH are raised
What is gonadotrophin independent (‘pseudo’, ‘false’) precocious puberty due to?
Excess sex hormones
FSH & LH are low
How can testes development indicate cause of precocious puberty in males?
Bilateral enlargement –> gonadotrophin release from intracranial lesion
Unilateral enlargement –> gonadal tumour
Small testes –> adrenal cause (tumour or adrenal hyperplasia)
What are some causes of true gonadotrophin dependent precocious puberty?
i.e. central
1) CNS lesions e.g. GnRH secreting hamartoma
2) CNS tumours
3) Central malformation or damage e.g. hydrocephalus, neurofibromatosis
4) Acquired: post-sepsis, surgery, radiotherapy, trauma, birth anoxia
What are some causes of false (gonadotrophin independent) precocious puberty?
i.e. peripheral –> causing increased secretion of sex hormones
1) Gonadal: ovarian cyst, ovarian tumour, Leidig cell tumour of testes
2) Adrenal: tumours, congenital adrenal hyperplasia
3) Ectopic hCG production by germ cell tumour
4) Exogenous sex steroids
5) Hypothyroidism
6) McCune Albright syndrome: polyostotic fibrous dysplasia
What is Kallman syndrome?
Genetic condition causing HYPOgonadotropic hypogonadism.
Features:
- failure to start puberty
- anosmia
What hormonal blood tests can be done in delayed puberty?
1) early morning FSH & LH
2) TFTs
3) prolactin
4) GH testing
What is often used as a screening test for GH deficiency?
Insulin-like growth factor I
Name 3 genetic conditions that can cause delayed puberty
1) Turner’s (XO)
2) Klinefelter’s (XXY)
3) Kallman’s
What investigation is indicated in Kallman’s ?
MRI to assess olfactory bulbs
What does a Leidig cell tumour produce?
Testosterone
What type of precocious pubety can a germ cell tumour cause? Why?
Germ cell tumours produce AFP and hCG.
Production of hCG can lead to gonadotrophin independent precocious puberty (as hCG directly stimulates the production of testosterone, oestrogen, & sperm).
