Paeds Written - ENDO Flashcards
1st sign of Male & Female puberty
Male = increase in testicular volume
- usually 12 yrs old (range 10-15)
- vol >4ml defines onset of puberty
Female = breast development
- ~11.5 yrs
- may be asymmetrical
Definition of precocious puberty
Development of secondary sexual characteristics before 8 years in female or 9 years in male
Types & mechanism of precocious puberty
Gonadotrophin dependent / central / true = premature activation of hypothalamic-pituitary-gonadal axis
Gonadotrophin independent / pseudo / false = excess sex hormones
Rare but important cause of precocious puberty
McCune Albright syndrome
- disorder of bone, skin & endocrine tissue
- abnormal scar like fibrous tissue in bones ‘polyostotic fibrous dysplasia’
- cafe au lait spots
- other endo issues e.g. thyrotoxicosis
Sex hormone results in precocious puberty
Central / Gonadotrophin dependent = LH, FSH raised
Pseudo / Gonadotrophin INdependent = LH, FSH low
Central / gonadotrophin dependent causes of precocious puberty
Idiopathic - 80% of girls, 40% of boys
CNS abnormality - tumour, trauma, central congenital disorder
Pseudo / gonadotrophin INdependent causes of precocious puberty
Ovarian - follicular cyst, Leydig cell tumour, granulosa cell tumour, gonadoblastoma
Testicular - Leydig cell tumour, testotoxicosis
Adrenal - Congenital adrenal hyperplasia, Cushing’s syndrome
Somatic tumour e.g. b-hCG secreting liver tumour
McCune Alright syndrome
Exogenous hormones - COCP, testosterone gel
Gold standard for Ix of (male) precocious puberty
GnRH stimulated LH/FSH
Size of testes in different types of precocious puberty?
Small = congenital adrenal hyperplasia
Bilateral enlargement = central cause - intracranial lesion e.g. optic glioma in NF1
Unilateral enlargement - sex cord gonadal stromal tumour
Medication options for Gonadotrophin DEPENDENT precocious puberty
GnRH agonist e.g. leuprolide + Growth hormone
GnRH agonist + cyproterone (anti-androgen)
Or no Tx if idiopathic
Medication options for Gonadotrophin INDEPENDENT precocious puberty
McCune Alright or Testotoxicosis
1st line = ketoconazole, cyproterone
2nd line = aromatase inhibitors
Causes of HYPO gonadotrophic hypogonadism
Hypo-thalamo pituitary disorders - panhypopituitarism, tumours
Kallman’s - LHRH deficiency, anosmia
Prader-Willi
Acquired hypothyroidism
Causes of HYPER gonadotrophic hypogonadism
Congenital
- cryptorchidism
- Klinefelter’s (47 XXY)
- Turner’s (45 X0)
Acquired
- testicular torsion
- chemotherapy
- infection
- trauma
- autoimmune
Functional causes of delayed puberty
Constitutional delay of growth & puberty
Chronic disease, malnutrition
Psych - over exercising, anorexia, depression
Medical management of delayed puberty
Pubertal induction
- Males = IM testosterone monthly for 6 months
- Females = transdermal oestrogen for 6 months THEN cyclical progesterone once established
+ Regular hormone replacement (only needed if primary failure NOT constitutional delay)
- Males = regular, as above
- Females = gradual oestrogen to avoid premature epiphyseal fusion + overdeveloped breasts
Key clinical features of Androgen Insensitivity syndrome
Phenotypic female
- breast buds
- sparse pubic hair
Bilateral groin swelling = immature undescended testes
Primary amenorrhoea
- absence of uterus + ovaries
Tx required for androgen insensitivity syndrome
Counselling!!
Bilateral orchidectomy - increased risk of testicular ca. if left undescended
Oestrogen therapy
T1 DM Diagnostic Criteria
Symptoms AND either fasting 7+ OR random 11.1+
No Sx AND 2 of:
- fasting 7+
- random 11.1+
- OGTT 11.1+
HbA1c 6.5%+ or 48+
Classical Triad of T1DM
Polyuria
Polydipsia
Weight loss
Insulin regimens
1st line = multiple daily injection ‘Basal-Bolus’
- short acting insulin with meals e.g. Lispro
- 1 or more separate injections of intermediate/long acting insulin (analogue) e.g. Glargine
2nd line = insulin pump
- usually rapid or short acting
- often needs to be for older child with good control
General principles of T1DM management
Same day referral to MDT paediatric diabetes team
Insulin therapy
Education
- diet, exercise
- insulin method
- hypo awareness & Tx
- DKA awareness
- BM home monitoring
Monitoring
- HbA1c 4+ times per year
- after 12 yo, annual checks for retinopathy, nephropathy, HTN
BSPED criteria for diagnosis of DKA
D - diabetes = BM > 11.1
K - ketones = >3
A - acidosis = pH <7.3
How to calculate fluid deficit for child with DKA
Deficit volume (to be replaced over 48 hours) = (% deficit x weight) - any fluid bolus if NOT shocked
NOTE: in shocked child - do not minus boluses
How to determine % fluid deficit in child with DKA
Mild DKA ph <7.3 = 5% fluid deficit
Moderate DKA pH <7.2 = 7% fluid deficit
Severe DKA pH <7.1 = 10% fluid deficit
Special requirements for choice of fluid in DKA?
Fluid bolus - can be 0.9% NaCl
Maintenance & deficit fluids:
- 0.9% NaCl
with 20mmol potassium chloride per 500ml
Fluid maintenance calculation in children?
First 10kg body weight = 100mL/kg/day
Next 10kg body weight = 50mL/lg/day
Each extra kg after that = 20mL/kg/day
E.g. 55kg child needs (10 x 100) + (10 x 50) + (35 x 20) = 2200mL over 24 hours
Insulin - dose & when to start in DKA?
0.05-0.1 units / kg / hour
Start infusion 1-2 hours after IV fluid replacement
NOTE: if on insulin pump, STOP
Monitoring needed during treatment of DKA
Hourly blood glucose Neuro status at least hourly Hourly fluid input:output U&E 2 hours after start of IV therapy THEN 4 hourly 1-2 hourly blood ketone levels
Criteria for ‘resolution of DKA’
Clinically well
Drinking well, tolerating food
Blood ketones <1.0 OR pH normal
NOTE: Urine ketones may still be positive
Complication seen during Tx of DKA?
Cerebral oedema
Tx:
- call senior staff!
- hypertonic saline
- mannitol
- restrict IV fluids by half
Genetics of Achondroplasia
Autosomal dominant inheritance
BUT ~70% of mutations are sporadic
FGFR3 mutations
Clinical features of osteogenesis imperfecta
Blue sclera Hearing loss Short stature Loose joints Breathing problems
Dwarfism definition
Height > 2.5 SD below the mean
Key clinical features of Achondroplasia
Short limbs + shortened fingers
Large head + frontal bossing
Flattened nasal bridge
‘Trident’ hand deformity
Lumbar lordosis
Radiological evidence of Achondroplasia
Metaphyseal irregularity
- inverted V metaphysis ‘chevron deformity’
Long bone flaring
Late appearing, irregular epiphyses
Pattern of growth in Nutritional/Chronic disease OR Psychosocial (deprivation / neglect) short stature
Falling off height centiles
Weight centile < height centile
Delayed bone age
Pattern of growth in Endocrine-related short stature
Falling of height centimes.
Weight centile > height centile (i.e. short + overweight)
Markedly delayed bone age.
Pattern of growth in constitutional delay
Short stature
Accentuated by delayed puberty
Delayed bone age
Pattern of growth in Familial short stature
Following growth centile
Within predicted range for mid-parental height
Causes of congenital hypothyroidism
Thyroid gland defect - missing, ectopic, poorly developed
Disorder of metabolism - TSH unresponsive, defect in TG structure
Hypothalami-pituitary dysfunction - tumours, ischaemia, congenital defect
Transient hypothyroidism - maternal meds (carbimazole) or Abs (hashimoto’s
Unique Sx of congenital hypothyroidism
Coarse features
Macroglossia
Umbilical hernia
Most common cause of hypothyroidism in childhood?
Hashimoto’s autoimmune thyroiditis
RF for childhood Hashimoto’s
Down’s syndrome
Turner’s syndrome
Safety netting advice for Hyperthyroidism drugs
Carbimazole + Propylthiouracil can cause neutropenia
Seek medical attention (+ do FBC) if sore throat or fever
