Endocrine

Question 1

What is the definition of precocious puberty for boys and girls ?

Answer 1

<8.5years girls

<9.5 years boys

Question 2

What are the characteristics clinical/investigation features of GnRH dependent precocious puberty ?

Answer 2

Progressive pubertal clinical changes 
Advanced bone age 
Accelerated linear growth 
High FSH, LH 
High oestradiol girls / testosterone boys

Question 3

What are 6 causes of central precocious puberty? What is the most common

Answer 3

Idiopathic 80% (almost always girls)
Hypothalamic hamartoma (most common CNS tumour)
International adoption
Other CNS tumours
Acquired CNS insults (radiation, hydrocephalus)
Neurofibromatosis type 1

Question 4

What is the treatment for central precocious puberty?

Answer 4

Leuprolide (Lucrin)
GnRH analogue - overrides pulsatile endogenous GnRH
Monitor by measuring LH suppression

Question 5

What is the triad defining McCune Albright syndrome ?

Answer 5

Cafe au lait spots (don’t cross midline, irregular Coast of Maine border, increase with age)
Peripheral precocious puberty
Polyostotic fibrous dysplasia

Question 6

What is the inheritance of McCune Albright Syndrome ?

Answer 6

Somatic/post zygotic mutation

Ie not inherited

Question 7

What investigation will differentiate central from peripheral precocious puberty ?

Answer 7

GnRH stimulation test

Question 8

Name 4 syndromal causes of hypogonadotrophic hypogonadism

Answer 8

CHARGE
Prader Willi
Kallman
Bardet Biedl

Question 9

Name a metabolic cause of hypergonadotrophic hypogonadism (girls)

Answer 9

Galactosaemia
(Deficiency in GALT)

Causes progressive ovarian failure - unclear mechanism

Question 10

What is the half life of T4 (thyroxine) ?

Answer 10

7 days

Question 11

What is the mechanism of action of carbimazole?

Answer 11

Inhibits thyroid peroxidase - inhibiting iodination of DIT and MIT
Thereby reducing production of T3 and T4

NB does not reduce T3/T4 release - takes weeks to have effect

Question 12

What is the m:f for Neonatal graves ?

Answer 12

Males = females

Question 13

What is the treatment for neonatal graves?

Answer 13

Lugol’s iodine - blocks T4 release, synthesis and uptake
Propranolol
Carbimazole

Question 14

What should you suspect with a cause of hearing difficulties, goitre and learning difficulties ?

Answer 14

Pendred syndrome

Question 15

What is the lifetime risk of T1DM for first degree relatives:

General pop
Paternal/ maternal offspring
Siblings
Twins

Answer 15

General pop 0.4% 
Parental offspring 8% 
Maternal offspring 3%
Siblings 5% 
HLA identical siblings 16% 
Monozygotic twins 30-50%

Question 16

Case of acidosis - can this be MODY?

Answer 16

No

Question 17

What is the risk of coeliac disease associated with T1DM?

Answer 17

10% < 5 yo

3% > 10yo

Question 18

What % of children with T1DM present with DKA?

Answer 18

25%

Question 19

What % of children with T1DM have no family history?

Answer 19

95%

Question 20

What age group for T1DM have the highest risk of DKA?

Answer 20

<2yo

And adolescents

Question 21

What is the defn of DKA - mild/mod/severe?

Answer 21

Hyperglycaemia > 20
Or low bicarbonate < 15

pH
< 7.1 severe
< 7.2 mod
< 7.3 mild

Question 22

Hyperthyroidism is a risk factor for DKA true or false ?

Answer 22

True

Increases basal metabolic rate

Question 23

What effect does insulin have on glucagon ?

Answer 23

Inhibits

Question 24

In regards to CFRD are macrovascular complications common?

Answer 24

No - almost never (fat malabsorption)

Question 25

What should you suspect for small baby presenting with hyperglycaemia, gradually improves Mum IVF

Answer 25

Transient neonatal diabetes

Question 26

Transient neonatal diabetes confers an increased risk of IDDM in later life - true or false?

Answer 26

True - in second decade

Question 27

Maternal IVF has no increased risk of genetic abnormalities - true or false

Answer 27

False - increased risk of methylation abnormalities / imprinting disorders

Question 28

What should you suspect with diabetes, seizures, developmental delay and muscle weakness?

Answer 28

DEND syndrome Developmental delay Epilepsy Neonatal diabetes

Question 29

What is the gene mutation associated with MODY 3?

Answer 29

HNF1A

Question 30

What is the gene mutation associated with MODY 1?

Answer 30

HNF 4A

Question 31

What are the phenotypic features of MODY 1?

Answer 31

Present in adolescence Progressive insulin secretory defect Foetal macrosomia Transient neonatal hypoglycaemia

Question 32

What is the gene mutation associated with MODY 2? | And what is the usual presentation /phenotypic features?

Answer 32

``` GCK Present since birth Stable mild hyperglycaemia Often asymptomatic May have abnormal OGT/GDM/LBW Microvascular complications are rare ```

Question 33

What is the gene mutation associated with MODY 3 and what is the phenotypic presentation ?

Answer 33

HMF 1A Present in adolescence Progressive insulin secretory defect Renal glycosuria

Question 34

What is the gene mutation associated with MODY 5? And what is the phenotypic presentation ?

Answer 34

``` HNF 1B Present in adolescence Progressive diabetes Pancreatic atrophy Exocrine dysfunction Renal/ urologic disease ```

Question 35

What is the mutation responsible for the majority of permanent neonatal diabetes due to pancreatic beta cell mutations ?

Answer 35

KATP channel (SUR1 or Kir 6.2) Mutation alters ability of channel to close Usually sulfonurea responsive

Question 36

What is DEND syndrome ?

Answer 36

Developmental delay Epilepsy Neonatal diabetes Most severe type of Kir 6.2 mutations (Channels also found in brain and muscle)

Question 37

What investigation is essential for girls with Turner syndrome prior to commencing pubertal induction ?

Answer 37

FSH - need to confirm that she hasn’t gone into spontaneous puberty (30%) despite 90% having gonadal failure Need to confirm FSH is elevated ie gonadal failure

Question 38

What should you suspect from a presentation of precocious puberty and gelastic seizures ?

Answer 38

central cause | Hypothalamic hamartoma

Question 39

Which cells secrete glucagon?

Answer 39

Alpha cells in pancreas

Question 40

Which cells secrete somatostatin ?

Answer 40

Delta cells in pancreas

Question 41

What has the most effect on peak bone mass ?

Answer 41

Genetic factors

Question 42

What is the mechanism of action of fludrocortisone?

Answer 42

Synthetic analogue of aldosterone | Increases BP