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Puberty Conditions
Precocious puberty
This is defined as the development of secondary sexual characteristics at an abnormally young age
– In females, this is before the age of 8 and before the age of 9 in males.
– Precocious puberty in females is usually due to premature onset of normal puberty whereas in males, it is more likely to be due to a pathological cause.
– Precocious puberty in males is more likely to be due to a pathological cause
We can categorise precocious puberty into two types:
Central
This is where there are disturbances to the central nervous system leads to elevated levels of GnRH causing early activation of the HPA axis and consequent production of testosterone/oestrogen
– This early production of sex hormones leads to the early development of secondary sexual characteristics
Causes:
– Genetic(familial)
– Hypothyroidism
– CNS abnormalities –> tumours, hydrocephalus, surgery/brain injury
Symptoms:
Signs of puberty at an early age which occur in the normal sequence (consonant)
Tests:
Blood tests shows high LH and FSH (with LH>FSH) and high testosterone/oestrogen
Management:
– You can use GnRH analogues to delay puberty
– Important to treat the underlying cause
Peripheral
This is where there is an elevated level of sex steroid hormones not due to increased GnRH secretions
– Instead, this is due to abnormalities at any level of the HPA axis downstream of the pituitary gland
Causes:
– Adrenal –> tumour, CAH
– Ovarian –> granulosa cell tumour
– Testicular –> Leydig cell tumour
– Exogenous sex steroids
Symptoms:
Signs of puberty at an early which may not occur in the normal order (dissonant)
Tests:
Low levels of LH and FSH (due to negative feedback) but high testosterone/oestrogen
Management:
– Detect and treat underlying cause if present
– Can use inhibitors of androgens or oestrogens to delay the puberty
Delayed Puberty
This is the development of secondary sexual characteristics at an abnormally late age during adolescence
– It is defined as the absence of secondary sexual characteristics by age of 14 in females and 15 in males.
– In contrast to precocious puberty, delayed puberty in males is more likely to be a normal variant whereas in females may be more likely due to an organic biological cause.
We can categorise delayed puberty into 3 types:
Constitutional delay of growth and puberty
This is the most common type of delayed puberty which is just a variation in normal timing of puberty
– There is no pathological process occurring, but instead maybe due to inherited genetic factors
– This is usually more common in boys than girls
Causes:
Due to family history or excessive dieting/physical training
Symptoms:
– Delayed development of secondary sexual characteristics
– Moderate delay in growth (but eventually target height is reached at an older age)
Tests:
Hormonal profile (LH, testosterone, prolactin)
Management:
– Usually no treatment is required apart from reassurance
– If the child is significantly distressed, then it is possible to give androgens to speed up the puberty process
Hypergonadotropic hypogonadism
This type is characterised by high levels of gonadotrophs FSH and LH with underdevelopment of the gonads
– In this type, there are direct ovarian or testicular failure leads to poor production of testosterone and oestogren
– This leads to reduced growth of the gonads and delay of secondary sexual characteristics
– However, low sex steroids mean less negative feedback on the pituitary gland leading to high levels of FSH and LH
Causes:
– Steroid hormone enzyme deficiencies –> e.g., 5-a-reductase deficiency
– Acquired testis/ovarian damage –> surgery, chemo/radiotherapy, trauma
– Chromosome abnormalities –> Klinefelter Syndrome (47 XXY), Turner syndrome (45X0)
Tests:
This shows high levels of FSH/LH with low levels of testosterone/oestrogen
Management:
Treat the underlying cause. May require exogenous sex hormone replacement.
Hypogonadotropic hypogonadism
This type is due to dysfunction of the hypothalamus or pituitary gland which gives low levels of FSH and LH
– This leads to downstream poor stimulation of the gonads leading to reduced production of oestrogen and testosterone
– As a consequence, there is poor gonad development and a delay in secondary sexualcharacteristics
Causes:
– Systemic diseases –> cystic fibrosis, anorexia, Crohn’s disease
– CNS disorders –> intracranial tumours (craniopharyngiomas), pituitary insufficiency
– Hypothyroidism
Kallman Syndrome
N.B. A specific condition that causes hypogonadotropic hypogonadism is Kallman’s Syndrome:
– This is an X-linked recessive condition where there is a failure of GnRH secreting neurons which originate in the olfactory epithelium to migrate to the hypothalamus, giving poor GnRH secretion
Symptoms:
– Gives delayed puberty and anosmia (lack of smell)
– Facial deformities –> cleft lip/palate
– CNS problems –> hearing loss and abnormal eye movements
– Associated with renal agenesis and abnormal finger/toe bones
– Patients are typically quite tall
Tests:
– Low GnRH, FSH/LH, oestrogen, and testosterone
– Normal levels of other pituitary hormones
Management:
Sex hormone replacement therapy