Paed:Endo Flashcards
Why measure children?
Provides a sensitive indication of health in childhood
Growth rates are narrowky defined in children w/ adequate nutrition and an emotionally supportive environment
Changes in growth rate can provide an early pointer to problems
Important determinants of growth?
Nutrition, parents, parental phenotype and genotype, quality and duration of pregnancy, psychosocial environment, Growth promoting hormones and factors
Puberty features in females?
Breast development - first sign, 8.5-12.yrs
Pubic hair growth and rapid height spurt
Menarche - occurs on average 2.5yrs after start of puberty and signals end
Puberty features in males?
Testicular enlargement to over 4ml volume
Pubic hair growth follows
Height spurt - when testicular volume is 12-15ml
How do you measure testicular volume?
Orchidometer
Changes in both sexes?
Acne
Axillary hair
Body odour
Mood changes
Methods of assessing puberty?
Bone age measurement of wrist
Females: pelvic uss for uterine size/endometrial thickness
What is meant by Short Stature?
Height below the 2nd centile (2.5SD below the mean) or 0.4th centile
Causes of short stature?
Familial IUGR Extreme prematurity Constitutional delay Endocrine (hypothyroidism, GH defiecinecy, corticosteroid excess, cushings) Nutritional/chronic illness Psycosociald deprivation Chromosomal disorders
investigations of short stature?
Measure sitting height and sub-ischial leg length.
GH, IGF-1, TSH, X-ray of wrist, cortisol and dexa suppression test
Treatment of short stature?
Daily GH injection and recombinant IGF-1 therapy
Causes of tall stature?
Primary:Familial, Obesity
Secondary: Hyperthyroidism, excess sex steroid, CAH, gigantism (increased GH), marfans
Syndromes that cause tall stature?
Marfans
Klinefelters
What is premature sexual development?
The development of secondary sexual characteristics before 8 years old in girls and 9 years old in boys.
What may premature sexual development be due to?
Precococious puberty
Premature breast development (thelarche)
Premature pubic hair development (pubarche/adrenarche)
What is precocious puberty?
True PP: Gonadotropin-dependent from premature activation of the hypothalamic-pituitary-gonadal axis
False PP: Gonadotropin-independent from excess sex steroids
Precocious puberty in females:
Usually idiopathic or familial.
USS of ovaries and uterus useful, often find multicystic ovaries and enlarging uterus
Precocious puberty in males:
Normally an organic cause, especially intercranial tumours. Tumours in hypothalalamic region investigated by MRI.
Exam of testes:
- bilateral enlargement suggests gonadotropin release usually from intercranial lesion
- small testes suggests an adrenal cause
- unilateral enlargement suggests gonadal tumour
How is premature thelarche differentiated from PP?
By absence of axillary and pubic hair and no growth spurt
What is premature pubarche?
Pubic hair develops before 8 in females and before 9 in males with no other signs of sexual development.
Caused by accelearation of androgen production of adrenal gland.
Investigations for prem pubarche?
USS of ovaries and uterus
Bone age - to exclude central prec pub
urinary steroid profile - differentiate from late CAH
What is delayed puberty?
The absence of pubertal development by 14 years old in females and 15 years old in males.
Causes of delayed puberty?
Constitutional delay/familial
Low gonadotropin secretion (hypogonadotropic hypogonadism) –> CF, asthma, crohns,kallman syndrome,
High gonadotropin secretion (hypergonadotropic hypogonadism) –> Klinefelters 47XXY, Turners 45X0
Treatment of delayed puberty?
Males: Oral Oxandrolone or low dose IM Testosterone
Females: Oestradiol
What is the defiency in CAH?
90% have a defiency in 21-hydroxylase enzyme, needed for cortisol biosynthesis.
About 80% also unable to produce Aldosterone, leading to salt loss (Increased potassium, low sodium)
What happens in utero in CAH?
In the fetus, cortisol defiency stimulates the pituitary to produce excess ACTH which drives overproduction of adrenal androgens.