Endocrine/Metabolic Flashcards

1
Q

causes and pathophysiology of T1DM

A

genetic predisposition which is then triggered after a viral infection, T cell mediated autoimmune destruction of B cells.
results in inability to secrete insulin, reduced fluid uptake leading to hyperglycaemia, dehydration and loss of electrolytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

pathophysiology of DKA

A

lipolysis causing the production of ketones which accumulates causing an metabolic acidosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Presentation of hypoglycaemia

A

lack of concentration, shaky, colic, LOC, drowsy, convulsions, coma.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

diagnosis of diabetes

A

random blood sugar of <11.1 and a fasting blood sugar of >7. With diabetic symptoms. will need two readings if asymptomatic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

investigations for query diabetes

A

random and fasting blood glucose.
TFTs, LFTs, U&Es, ANA
Urinalysis
retinal screening

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Management of T1DM

A

Target HbA1c <48 without frequent hypoglycemia
lifestyle: healthy diet, awareness of sugar content and spikes, regular carbohydrate intake.
insulin therapy: sub cut injections, long acting and rapid release. pens, pumps are available.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Complications of T1DM

A

decrease compliance in teenagers - more prone to DKA and hypos.
depression, psychosocial problems.
microvascular, macrovascular complications.
risk of other autoimmune conditions - coeliac, graves, hashimotos.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

definition of failure to thrive

A

when a child drops more than 2 centiles on their growth chart (1 if they are already below the 9th centile)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

causes of failure to thrive

A

inadequate intake - incorrect feeding, poor technique, difficult child
increases outward products - vomiting, GI disturbance, neurological problems
increased requirements - congenital heart defects, respiratory conditions, immunodeficient
non-organic cause - neglect, eating disorders, Munchausen syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

key things to ask for failure to thrive history

A

BINDS, recurrent infections, lethargy, feeding history.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

investigations for failure to thrive

A

assessment for signs of neglect, maternal/paternal mental health.
• Bloods: FBC (may be anaemic), ESR, CRP, U&E, LFTs, TFTs
• Coeliac screen, urinalysis, CXR, CF sweat test.
• Genetic testing/karyotyping if indicated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

most common cause of ambiguous genetailia

A

congenital adrenal hyperplasia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is congenital adrenal hyperplasia?

A

reduced synthesis of hydrocortisol due to an absent 21 hydroxylase enzyme. this results in inefficient steroid hormones, increased aCTH and increased cortisol hypertrophy and increased androgens. Effects females.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

three types of ambiguous genetailia

A

se chromosome disorders, excess androgen exposure in XX, or errors in testosterone synthesis and LH deficiency in XY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how common is congenital adrenal hyperplasia?

A

1/18,000 births

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

enzyme deficiency in XY disorders of sexual development

A

defective testosterone production due to 5-a-reductase deficiency.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is precocious puberty? who does it commonly effect?

A

signs of puberty in boys <9, girls <8.

5X more common in girls, usually HF, obesity, more common in afrocarribean decent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

central and peripheral causes of precocious puberty

A

central: gonadotrophin dependent - premature activation of HPA, no cause or rarely due to CNS lesion
peripheral: gonadotrophin independent - gonad maturation without GnRH stimulation, due to Congenital adrenal hyperplasia, hypothyroidism, McCune-Albright syndrome.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

management for precisious puberty

A

if no pathology: no need for treatment
if congenital adrenal hyperplasia: glucocorticoids
in central cause: can use GnRH agonists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

investigations for precocious puberty

A

Tanner staging of the extent of the puberty.
Bone age
Hormone profile: LH, FSH, TFT, HCG, testosterone
imaging: USS, dexa scan, brain MRI

21
Q

causes of delayed puberty

A

central: constitutional delay, chronic disease, nutritional deficiency, pituitary problems
peripheral: testicular or ovarian damage

22
Q

LH and FSH findings in the central and peripheral causes of pubertal delay

A

Central causes: low LH and FSH

Peripheral: high LH and FSH

23
Q

what happens in each of the tanner stages?

A

stage 1 - pre-pubertal
stages 2-3 - in puberty (height velocity in girls)
stages 4-5 completion (height velocity for boys)

24
Q

What stimulates puberty?

A

resurgence of GnRH, stimulating the maturation of the gonads, increasing FSH and LH.

25
Q

what is constitutional delay?

A

long standing short stature in childhood and slow pubertal progression, strong family history, no management needed, will also have delayed bone age.

26
Q

Name the 4 phases of growth and the key hormomes responsible at each (not at 1st stage)

A

1) Intrauterine - most rapid stage
2) Infantile - thyroxine most important for growth
3) Childhood - growth hormone most important
4) Pubertal - oestrogen/testosterone

27
Q

Investigations for delayed puberty

A

check general health, plot height and weight, tanner staging
hormone levels: LH, FSH, oestrogen, testosterone, prolactin, TFTs
check for evidence of chronic disease
karyotypic
imaging: may need pelvic USS or head MRI of pituitary.

28
Q

causes of congenital hypothyroidism

A

thyroid glad defects - missing or poorly develop
metabolism defects - TSH unresponsive
hypothalamic dysfunction - tumours, ischaemic damage
transient - due to maternal medication or antibodies crossing the placenta.

29
Q

presentation of congenital hypothyroidism

A

Infant: thick protruding tounge, pale skin, constipation, prolonged jaundice, poor muscle tone, bradycardia, umbilical hernia.

growing child: will have sort stature, depressed bride of nose, neurological same and delayed learning development.

30
Q

how is hypothyroidism diagnosed?

A

screening through the heel prick test.

diagnosis: high TSH and low T4.

31
Q

risk factors for congenital hypothyroidism? what is the prevalence?

A

girls, genetic defects PAX8 DUOX2. prevalence is 1/4000

32
Q

causes of obesity: idiopathic, endocrine and genetic

A

Idiopathic - poor diet and reduced exercise, sedentary life
Endocrine - hypothyroidism, Cushing’s disease (short stature, muscle wasting)
Genetic - leptin deficiency, prader-willi syndrome

33
Q

complication of obesity in childhood

A

SUFE (slipped upper femoral epiphysis), MSK pains, poor self esteem, sleep apnoea, T2DM, NAFLD, PCOS.

34
Q

what is phenylketonuria

A

inborn error or amino acid metabolism, also known as folling disease.

35
Q

Causes of phynylketonuria

A

type 1: inherited autosomal recessive, alteration in chromosome 12 - due to absent phenylalanine hydroxylase enzyme activity. (resulting to the build up of phenylalanine).

Can present later, or be secondary due to malignancy.

36
Q

Function of the phenylalanine hydroxylase enzyme

A

Converts dietary phenylalanine to tyrosine, which is used in the formation of neurotransmitters, melanin and catecholamines.

37
Q

Presentation of phenylketonuria

A

most picked up at newborn heel prick screening.

presentation: fair child with blue eyes, developmental delay, seizures, eczematous skin, may have recurrent vomiting.

38
Q

investigation for phenylketonuria

A

heel prick test
urinalysis - raised ketones
tyrosine assay
can use MRI in older children

39
Q

Management of Phenylketonuria

A

Dietary control: low phenylalanine and high tyrosine foods - protein restriction and substitution of he correct amino acid balance
vitamin and iron supplementations

40
Q

Causes of short stature

A

Primary causes:
Familial
Constitutional - delay in bone age and strong FH
Chromosomal
IGUR,
Bone disorders eg osteogenesis imperfecta, achondroplasia)

Secondary causes:
endocrine - Cushing’s, hypothyroidism, GH deficiency
Metabolic - diabetes
Chronic disease - respiratory disease, IBD, malnutrition
Deprivation.

41
Q

Investigations for short stature (if query organic cause)

A

Bloods: FBC, U&Es, Coealic antibodies, TFTs, GH

Bone age - XR of hand and wrist

42
Q

Define short stature

A

2 SD below the mean hight for that age and sex. OR below the 2nd centile.

43
Q

formula for mid-parental hgeight

A

Boy: (Mum Height + Dads Height +13) /2
Girls: (Mum Height + Dads Height -13) /2

44
Q

Assessment of growth

A
Measure height using Harpenden stadiometer.
Plot of growth charts
Calculate mid-parental height
Bone age - XR of growth plates
Height Velocity
45
Q

How do you correct for PTB when plotting growth?

A

Correct by however many weeks they were pre-term (up to 40 weeks) until they are 2 years of age.
eg if they are born at 32 weeks, need to correct for 8 weeks. if they are seen at 6 months, plot at 6 months minus 8 weeks.

46
Q

What is constitutional delay? what is the management?

A

Long standing short stature and delay to reach puberty. Will have a strong family history, delayed bone age (need to investigate further to rule out organic cause).
No management requirement.

47
Q

what heart defect is associated with turners syndrome?

A

Coarctation of the aorta

48
Q

what is the heart mumur heard in turners syndrome?

A

ejection systolic murmur, due to bicuspid aortic valve