Paeds Written - ENDO

Question 1

1st sign of Male & Female puberty

Answer 1

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

Question 2

Definition of precocious puberty

Answer 2

Development of secondary sexual characteristics before 8 years in female or 9 years in male

Question 3

Types & mechanism of precocious puberty

Answer 3

Gonadotrophin dependent / central / true = premature activation of hypothalamic-pituitary-gonadal axis

Gonadotrophin independent / pseudo / false = excess sex hormones

Question 4

Rare but important cause of precocious puberty

Answer 4

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

Question 5

Sex hormone results in precocious puberty

Answer 5

Central / Gonadotrophin dependent = LH, FSH raised

Pseudo / Gonadotrophin INdependent = LH, FSH low

Question 6

Central / gonadotrophin dependent causes of precocious puberty

Answer 6

Idiopathic - 80% of girls, 40% of boys

CNS abnormality - tumour, trauma, central congenital disorder

Question 7

Pseudo / gonadotrophin INdependent causes of precocious puberty

Answer 7

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

Question 8

Gold standard for Ix of (male) precocious puberty

Answer 8

GnRH stimulated LH/FSH

Question 9

Size of testes in different types of precocious puberty?

Answer 9

Small = congenital adrenal hyperplasia

Bilateral enlargement = central cause - intracranial lesion e.g. optic glioma in NF1

Unilateral enlargement - sex cord gonadal stromal tumour

Question 10

Medication options for Gonadotrophin DEPENDENT precocious puberty

Answer 10

GnRH agonist e.g. leuprolide + Growth hormone

GnRH agonist + cyproterone (anti-androgen)

Or no Tx if idiopathic

Question 11

Medication options for Gonadotrophin INDEPENDENT precocious puberty

Answer 11

McCune Alright or Testotoxicosis
1st line = ketoconazole, cyproterone
2nd line = aromatase inhibitors

Question 12

Causes of HYPO gonadotrophic hypogonadism

Answer 12

Hypo-thalamo pituitary disorders - panhypopituitarism, tumours

Kallman’s - LHRH deficiency, anosmia

Prader-Willi

Acquired hypothyroidism

Question 13

Causes of HYPER gonadotrophic hypogonadism

Answer 13

Congenital

• cryptorchidism
• Klinefelter’s (47 XXY)
• Turner’s (45 X0)

Acquired

• testicular torsion
• chemotherapy
• infection
• trauma
• autoimmune

Question 14

Functional causes of delayed puberty

Answer 14

Constitutional delay of growth & puberty

Chronic disease, malnutrition

Psych - over exercising, anorexia, depression

Question 15

Medical management of delayed puberty

Answer 15

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

Question 16

Key clinical features of Androgen Insensitivity syndrome

Answer 16

Phenotypic female

• breast buds
• sparse pubic hair

Bilateral groin swelling = immature undescended testes

Primary amenorrhoea
- absence of uterus + ovaries

Question 17

Tx required for androgen insensitivity syndrome

Answer 17

Counselling!!

Bilateral orchidectomy - increased risk of testicular ca. if left undescended

Oestrogen therapy

Question 18

T1 DM Diagnostic Criteria

Answer 18

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+

Question 19

Classical Triad of T1DM

Answer 19

Polyuria
Polydipsia
Weight loss

Question 20

Insulin regimens

Answer 20

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

Question 21

General principles of T1DM management

Answer 21

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

Question 22

BSPED criteria for diagnosis of DKA

Answer 22

D - diabetes = BM > 11.1

K - ketones = >3

A - acidosis = pH <7.3

Question 23

How to calculate fluid deficit for child with DKA

Answer 23

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

Question 24

How to determine % fluid deficit in child with DKA

Answer 24

Mild DKA ph <7.3 = 5% fluid deficit
Moderate DKA pH <7.2 = 7% fluid deficit
Severe DKA pH <7.1 = 10% fluid deficit

Question 25

Special requirements for choice of fluid in DKA?

Answer 25

Fluid bolus - can be 0.9% NaCl Maintenance & deficit fluids: - 0.9% NaCl with 20mmol potassium chloride per 500ml

Question 26

Fluid maintenance calculation in children?

Answer 26

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

Question 27

Insulin - dose & when to start in DKA?

Answer 27

0.05-0.1 units / kg / hour Start infusion 1-2 hours after IV fluid replacement NOTE: if on insulin pump, STOP

Question 28

Monitoring needed during treatment of DKA

Answer 28

``` 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 ```

Question 29

Criteria for 'resolution of DKA'

Answer 29

Clinically well Drinking well, tolerating food Blood ketones <1.0 OR pH normal NOTE: Urine ketones may still be positive

Question 30

Complication seen during Tx of DKA?

Answer 30

Cerebral oedema Tx: - call senior staff! - hypertonic saline - mannitol - restrict IV fluids by half

Question 31

Genetics of Achondroplasia

Answer 31

Autosomal dominant inheritance BUT ~70% of mutations are sporadic FGFR3 mutations

Question 32

Clinical features of osteogenesis imperfecta

Answer 32

``` Blue sclera Hearing loss Short stature Loose joints Breathing problems ```

Question 33

Dwarfism definition

Answer 33

Height > 2.5 SD below the mean

Question 34

Key clinical features of Achondroplasia

Answer 34

Short limbs + shortened fingers Large head + frontal bossing Flattened nasal bridge 'Trident' hand deformity Lumbar lordosis

Question 35

Radiological evidence of Achondroplasia

Answer 35

Metaphyseal irregularity - inverted V metaphysis 'chevron deformity' Long bone flaring Late appearing, irregular epiphyses

Question 36

Pattern of growth in Nutritional/Chronic disease OR Psychosocial (deprivation / neglect) short stature

Answer 36

Falling off height centiles Weight centile < height centile Delayed bone age

Question 37

Pattern of growth in Endocrine-related short stature

Answer 37

Falling of height centimes. Weight centile > height centile (i.e. short + overweight) Markedly delayed bone age.

Question 38

Pattern of growth in constitutional delay

Answer 38

Short stature Accentuated by delayed puberty Delayed bone age

Question 39

Pattern of growth in Familial short stature

Answer 39

Following growth centile | Within predicted range for mid-parental height

Question 40

Causes of congenital hypothyroidism

Answer 40

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

Question 41

Unique Sx of congenital hypothyroidism

Answer 41

Coarse features Macroglossia Umbilical hernia

Question 42

Most common cause of hypothyroidism in childhood?

Answer 42

Hashimoto's autoimmune thyroiditis

Question 43

RF for childhood Hashimoto's

Answer 43

Down's syndrome | Turner's syndrome

Question 44

Safety netting advice for Hyperthyroidism drugs

Answer 44

Carbimazole + Propylthiouracil can cause neutropenia | Seek medical attention (+ do FBC) if sore throat or fever