Metabolic medicine

Question 1

Define hypoglycaemia

Answer 1

Blood glucose <2.6

Question 2

What investigations would you do for hypoglycaemia?

Answer 2

Insulin level
c-peptide
Growth hormone level
Free fatty acid
Ketone bodies
Cortisol

Question 3

What is significance of c-peptide level in context of hypoglycaemia ?

Answer 3

Level should be same as insulin. If LOWER than insluin level suggests child being given extra insulin. - SAFEGUARDING

Question 4

What investigations would you consider for a new presentation of metabolic acidosis

Answer 4

Ketones!
Acylcornitine
Ammonia
Lactate
Urine organic acid
Plasma amino acids
ALWAYS CALCULATE ANION GAP

Answer 5

([NA+] + [K+]) - ([HCO3-] + [CL-])
Normal is 10-14

Question 6

What causes metabolic acidosis with rasied anion gap?

Answer 6

Lactic acidosis
DKA
Poisoning with: salicylate, methanol, propylene glycol, iron, isoniazid, ethylene glycol
Renal failure
Acid producing metabolic disorders

Question 7

What causes metabolic acidosis with normal anion gap?

Answer 7

Renal tubular acidosis
Addison’s disease
Acetozolamide use
Severe diarrhoea
Post-ureteric diversion into large bowel

Question 8

Describe idiopathic ketotic hypoglycaemia

Answer 8

Presenting in first few years with hypoglycaemia and ketones during intercurrent illness or prolonged fast. Treat with emergency glucose and avoid fasting.
resolves by 8 years of age
Diagnosis of exclusion

Question 9

Describe Glycogen storage disease 1

Answer 9

AR
Presents before 2 years of age with hypoglycaemia, hepatomegaly, seizure, poor growth/development
Low glucose, H lactate, ketone, and lipid.
Treat with frequent feeds and gastric feeds overnight.
Emergency feeding when unwell.

Question 10

What are the lab findings of Galactosaemia

Answer 10

Conjugated bilirubinaemia , deranged coag and metabolic acidosis, urinary reducing substances, glycosuria, aminoaciduria, albuminuria.

Question 11

Describe Galactosaemia, it’s mode of inheritance and how it usually presents

Answer 11

AR
Cannot metabolise galactose
Presents as jaundice, poor feeding, cataracts, e-coli sepsis

Question 12

What is the treatment for Galactosaemia?

Answer 12

Never have galactose
Manage cataracts
Girls infertile- see endocrine

Question 13

Describe Medium Chain Acyl-CoA dehydrogenase deficiency (MCAAD)

Answer 13

Part of neonatal screening
Can present before with poor feeding, generally unwell and seizures.

Question 14

What are lab findings for MCAAD?

Answer 14

Non-ketotic hypoglycaemia

Question 15

What is treatment for MCAAD?

Answer 15

Avoid prolonged fasting and take extra calories when ill
Will otherwise have normal development and growth

Question 16

What test suggests MPS?

Answer 16

Aminoglycosides in urine

Question 17

What are features of urea cycle disorders?

Answer 17

Poor feeding, seizures and reduced GCS in 1-5 days of life
Lab: Resp alkalosis, +++ammonia, plasma ammonia high and urinary organic acids present.

Question 18

What is the treatment for urea cycle disorder?

Answer 18

Acute: NBM, 10% dextrose +electroyltes. Sodium benzoate + haemofiltration.
Lifelong low protein diet + ammonia scanvengers

Question 19

What is the treatement for Phenylketonuria?

Answer 19

Low protein diet and regular phenylalanie monitoring

Question 20

Describe homocystinuria

Answer 20

AR. In newbrn screen
Down and out lens dislocation, tall, ID, aortic and mitral valve regurg, pectus excavatum.
Needs plasma amino acid screen

Question 21

What is the treatment for homocystinuria?

Answer 21

Pyridoxine and B6, low protein diet.

Question 22

Describe Maple Syrup Urine Disease

Answer 22

In newborn screen
Presents as progressive encephalopathy + sweet piss. Often looks like sepiss

Question 23

What are the lab findings for maple syrup urine disease?

Answer 23

Metabolic acidosis, rasied annion gap, +++ ammonia

Question 24

Describe Leigh’s Syndrome

Answer 24

Mitochondrial disease
Sub-acute sclerosing encephalopathy
Presented as 2-3 yr old with developmental delay/ seizure/ myopathy
Raised lactate and classic MRI findings