Overview

• Children below 2nd centile for height should be reviewed by their GP.
• Children below 0.4th centile for height should be reviewed by a paediatrician.

Delayed Puberty

• Females: no breast development by 13yo or no periods by 15yo. Males: no testicular development (≤4ml) by 14yo.
• Androgen Insensitivity Syndrome [46XY] → genotypically male children (46XY) have a female phenotype. Delayed puberty (primary amenorrhoea) in a ‘girl’ with bilateral groin swellings (undescended testes).
• Growth Faltering and Referral
  • ≥75th Centile → refer once centile drops by 3.
  • 25th-75th Centile → refer once centile drops by 2.
  • ≤25th Centile → refer when centile drops by 1.
• Aetiology
  • Functional (Most Commonly) → constitutional delay of growth and puberty (CDGP).
    • Commonest in boys. Usually FHx of same delay in parent of same sex. Sx: low bone age, no puberty signs, no organic causes. May initially be on track on growth curve then falls later in childhood. (Familial Short Stature → both parents are short, follows consistent slow growth curve, puberty not delayed, normal bone age).
    • Psychiatric → excessive exercise, anorexia nervosa.
  • Hypogonadotrophic (Low LH + FSH) Hypogonadism → panhypopituitarism, intercranial tumours, kallman’s syndrome [anosmia in boy with delayed puberty].
  • Hypergonadotrophic (High LH + FSH) Hypogonadism → klinefelter’s syndrome (47XXY) [small testes, gynaecomastia], turner’s syndrome (45 XO).
• Ix
  • Initial → charting (height and weight, mid-parental height) and note dysmorphic features. Prader’s orchidometer (boys) and tanner’s staging (girls).
  • Bloods → LH & FSH (GONADOTROPHINS), TSH, Prolactin, Testosterone.
  • Imaging → bone age (wrist x-ray), MRI brain.
  • Karyotyping.
• Mx
  • CDGP → 1st Line: reassure and offer observartion. 2nd Line: short course sex hormone therapy (6 months of IM testosterone in boys or transdermal oestrogen in girls).
  • Primary Testicular / Ovarian Failure → pubertal induction via regular hormone replacement. Boys: regular testosterone injections, Girls: oestrogen replacement.

Precocious Puberty

• <8 years old in females (puberty determined by breast development) and <9 years old in males (puberty determined by testicular development >4mL).
  • Females →
  • Males → bilateral testes enlargement: GDPP = intracranial lesion. Unilateral testes enlargement: gonadal tumour. Small testes: gonadotrophin-independent = adrenal cause (tumour or CAH).
• Gonadotrophin-Dependent (Central) → due to premature activation of HPG axis (raised FSH + LH). CNS abnormalities / Idiopathic in Females. More common in girls.
• Gonadotrophin-Independent (LOW FSH + LH) → due to increased sex hormones (low FSH + LH). Gonads (Testicular/Ovarian Tumour) / Adrenal (CAH/Tumour) / McCune-Albright Syndrome (cafe-au-lait spots, fibrous dysplasia). More common in boys.
• Benign Isolated Precocious Puberty (→ normal bone age):
  • Premature Thelarche → isolated breast development before 8yo, normally between 6m-2yo. Generally self-limiting.
• Ix → gold-standard: GnRH stimulation test. (LH/FSH suppressed if gonadotrophin-independent).
  • Females: pelvic USS. Males: examination of testes, MRI (intracranial tumours).
• Mx → refer to paediatric endocrinologist.
  • Can give GnRH agonist for GDPP.

Skeletal Dysplasia

• Achondroplasia (most common type of skeletal dysplasia) → autosomal dominant (70% sporadic mutatoins in FGFR3). Sx: short stature (arms and legs short, normal length thorax), lumbar lordosis, trident hands.