Clinical Conditions Flashcards

0
Q

What are the clinical consequences and symptoms of G6PD deficiency? When do symptoms appear?

A

Low NADPH levels, disulphide bridges form between Hb cysteine residues, Heinz bodies form, increased destruction of rbcs leads to anaemia, jaundice and fatigue. Disulphide bridges in eye lens cause cataracts. Symptoms appear at times of oxidative stress, infection etc

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

What is the cause of G6PD deficiency?

A

X linked genetic condition

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

What are symptoms of both types of galactosaemia? Which is more severe?

A

Kinase- cataracts caused by low NADPH levels in eye
Transferase- same as kinase but more severe as also damage to liver, kidney and brain due to build up of glucose-1-phosphate
Symptoms present in newborns and must be treated quickly

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

What is galactitol and explain its significance in galactosaemia?

A

When galactose builds up (e.g. in galactosaemia) it is converted to galactitol, converting NADPH to NADP.

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

How can deficiency in galactose 1 P uridyl transferase cause jaundice?

A

Leads to build up of glucose 1 phosphate, this damages liver, reducing its ability to conjugate haemoglobin, causing Hb build up = jaundice

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

What are the two causes of galactosaemia and which is most common?

A

Deficiency of Galactokinase enzyme or deficiency of galactose (1 phosphate uridyl)transferase, transferase is most common.

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

What is the cause and possible effects of a glycogen storage disease?

A

Genetic cause, deficiency/dysfunction of an enzyme
Excess storage- tissue damage
Diminished storage- hypoglycaemia, low exercise tolerance (Von Gierkes)

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

What is the cause of phenylketonuria?

A

Deficiency of phenylalanine hydroxylase, can’t metabolise phenylalanine so it accumulates and is converted to phenyl ketones

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

How, when and why is PKU diagnosed?

A

Heel prick test in newborns, must be detected early as if left untreated brain development is stunted

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

How is PKU managed?

A

Special diet, low in phenylalanine

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

What causes homocysteinuria?

A

Deficiency of CBS enzyme, leads to increased level of homocysteine and methionine

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

What are the effects to the body of homocysteinuria?

A

Damage to connective tissue, muscle, CNS, cardiovascular system

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

What can homocysteinuria often be mistaken for?

A

Marfan’s syndrome

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

Describe the cause, symptoms and treatment of marasmus…

A

Cause- general malnutrition, under fed, usually children <5
Symptoms- muscle wasting, loss of body fat, hair dry and thin, may have diarrhoea, anaemia
Treatment- gradually build up diet

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

Describe the cause, symptoms and treatment for Kwashiorkor…

A

Cause- low protein diet
Symptoms- lethargy, loss of appetite, oedema, hepatomegaly, low serum albumin, often anaemia
Treatment- gradual reintroduction of protein into diet

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

What is the treatment for galactosaemia?

A

No dairy!!

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

Describe hyperlipoprotainaemia, it’s causes and symptoms…

A

High levels of one or more classes of lipoprotein
Cause- under removal/over storage/defective enzyme, receptor or apoprotein
Symptoms- xanthelasma, corneal arcus, can lead to atherosclerosis/CHD

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

Describe the process of atheroma formation…

A

Oxidised LDLs taken up by macrophages, macrophages become foam cells, foam cells accumulate in wall of blood vessel (fatty streak), fatty streak expands and swells = atheroma

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

What is the treatment of hyperlipoprotainaemia?

A

Diet- lower cholesterol and saturated fat
Lifestyle- more exercise, stop smoking,
Statins- inhibit HMG CoA reductase, lower production of cholesterol by body,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How is paracetamol metabolised during an overdose and why is this harmful?

A

Normal phase II pathway is saturated, goes through phase I, converted to NAPQI, NAPQI conjugated with glutathione, glutathione antioxidant used up leaving liver cells open to to attack by ROS which damages/kills them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the treatment for paracetamol overdose and what is the time frame for effectiveness?

A

<8 hours after exposure, give N-acetylcysteine, any longer then damage has already been done so a liver transplant is needed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the pathway for alcohol metabolism?

A

Alcohol converted to acetaldehyde by alcohol dehydrogenase, then to acetic acid using aldehyde dehydrogenase. Acetic acid can then be converted to acetyl CoA and enters the Krebs cycle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What causes the adverse effects of alcohol?

A

The intermediate, acetaldehyde

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the consequences of prolonged binge drinking?

A

Fatty liver, alcoholic hepatitis, alcoholic cirrhosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What causes fatty liver in alcoholics?

A

Excess NADH from the metabolism of alcohol increases fat deposition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What can alcoholics be given to stop their addiction and how does it work?

A

Disulfiram- inhibits aldehyde dehydrogenase so acetaldehyde builds up causing a very very bad hangover, lasting days, hopefully this is bad enough to put them off for good

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the symptoms of hypoglycaemia?

A

Slurred speech, staggering, confusion, loss of consciousness, eventually death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the consequences of a leptin deficiency?

A

Appetite isn’t adequately suppressed, keep eating, get very, very fat like ob/ob mouse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the symptoms of metabolic syndrome?

A

Insulin resistance, dyslipidaemia, impaired glucose tolerance, type II diabetes, hypertension, obesity

31
Q

What is included in the WHO criteria for metabolic syndrome?

A

Waist/hip ratio, BMI over 30, high blood pressure, high TAGs, low HDLs, high fasting glucose

32
Q

What is the typical presentation of someone with type I diabetes?

A

Young, thin, recent viral infection, symptoms- polyuria, polydipsia and weight loss

33
Q

What is the typical presentation of someone with type II diabetes?

A

Older person, overweight, symptoms- as type I, or lethargy, persistent infections (thrush, feet), visual problems

34
Q

What is the cause of type I diabetes?

A

Autoimmune destruction of beta cells in pancreas

35
Q

What is the cause of type II diabetes?

A

Insulin resistance due to a high glucose diet, some gradual loss of beta cells

36
Q

Why must type I diabetes be spotted and treated quickly?

A

Untreated it leads to ketoacidosis- the body goes into starvation mode without insulin allowing it to take up glucose, ketones are produced, lower blood pH- fatal if untreated

37
Q

How can diabetes be diagnosed? (3 tests)

A

Fasting glucose >7mmol
Glucose tolerance test
HbA1c test >6.5%

38
Q

What is the treatment for type I diabetes?

A

Patient education, regular insulin injections, diet, exercise

39
Q

What is the treatment for type II diabetes?

A

Diet, exercise, then non insulin drugs e.g. Sulphonylureas, metformin, finally insulin

40
Q

What are the long term side effects of diabetes?

A

Increased stroke and MI risk, diabetic eye disease, retinopathy, glaucoma, diabetic kidney disease, diabetic neuropathy, diabetic feet

41
Q

What are the causes of Cushing syndrome?

A

Exogenous- long term steroid use

Endogenous- pituitary tumour, ectopic tumour (ACTH secreting), primary adrenal tumour (cortisol secreting)

42
Q

How could you distinguish between the different endogenous causes of Cushing’s?

A

Adrenal tumour- increased cortisol, but decreased ACTH
Pituitary or ectopic- dexamethasone test, low dose, both respond the same, high dose- pituitary suppresses, ectopic doesn’t suppress

43
Q

What causes Cushing’s disease?

A

Pituitary tumour

44
Q

What is the treatment for Cushing’s disease?

A

Removal of the pituitary tumour

45
Q

What are the symptoms of Cushing’s?

A

Central obesity, purple striae, reddened and moon shaped face, easy bruising, hyperglycaemia (steroid diabetes)

46
Q

What causes Addison’s disease?

A

Autoimmune destruction of adrenal cortex causing reduced cortisol secretion

47
Q

What are the symptoms of Addison’s disease?

A

Lethargy, muscle weakness, anorexia, weight loss, dehydration, hyperpigmentation, postural hypotension, hypoglycaemia

48
Q

What is another cause of low cortisol levels?

A

Problem with pituitary gland ACTH secretion

49
Q

How would you diagnose Addison’s?

A

Use a SynACTHen test- synthetic ACTH to stimulate cortisol secretion, if cortisol doesn’t rise then have Addison’s

50
Q

What is the most common cause of hypothyroidism?

A

Hashimoto’s- autoimmune destruction of follicular cells or antibody produced that blocks TSH receptors

51
Q

What are the symptoms of hypothyroidism?

A

Weight gain, cold intolerance, bradycardia, constipation, lethargy, weakness, dry and flaky skin, alopecia, depression

52
Q

What is the treatment for hypothyroidism?

A

Oral thyroxine (T4), start with low dose and gradually increase until symptoms disappear

53
Q

Why are all babies screened for congenital hypothyroidism?

A

Lack of thyroid hormone in development causes cretinism- stunted growth and mental retardation- but this can be avoided if detected quickly and treated immediately with T4

54
Q

What is the main cause of hyperthyroidism?

A

Grave’s disease- autoimmune condition, antibodies are produced that mimic TSH and activate thyroxine secretion

55
Q

What are the symptoms of hyperthyroidism?

A

Weight loss, heat intolerance, tachycardia, physical and mental hyperactivity, diarrhoea, lethargy, exophthalmos and lid lag

56
Q

What are the treatment options for hyperthyroidism?

A

Carbimazole (inhibits coupling and iodination of tyrosine residues) if unsuccessful, radioactive iodine to destroy thyroid or surgery to remove it, then T4 replacement

57
Q

What causes Hypocalcaemia?

A

Deficiency of vitamin D/calcium or hypoparathyroidism caused by accidental removal of parathyroid, or autoimmune condition

58
Q

What causes hypercalcaemia?

A

Benign tumour of parathyroid gland (hyperparathyroidism) or PTHrP secreting tumour e.g. Breast, prostate cancer

59
Q

What are the symptoms of Hypocalcaemia?

A

Tetany, paralysis, convulsions and eventually death if affects respiratory muscles

60
Q

What are the symptoms of hypercalcaemia?

A

Kidney stones, constipation, lethargy, depression (stones, moans and groans!)

61
Q

Why does gestational diabetes occur?

A

Mother’s pancreas is unable to cope with the increased demand for insulin during pregnancy so control is lost and glucose levels increase, disappears after birth as insulin demand decreases

62
Q

What causes sickle cell anaemia?

A

Single base substitution- A>T causes glutamate > valine, forms sticky hydrophobic pocket which causes polymerisation of Hb in the t state, causes Sickling

63
Q

How is sickle cell managed?

A

Patient education, avoid stressors e.g. Infection, cold, intense exercise (causing hypoxia)

64
Q

What are the types of thalassemia and what are they?

A

Usually 2 alpha, 2 beta subunits in Hb
Alpha thalassemia- decreased/absent alpha globins in the individuals blood
Beta thalassemia- decreased/absent beta globins

65
Q

Give an example of a disease with an autosomal recessive inheritance pattern…

A

Cystic fibrosis

66
Q

Give an example of a disease with an autosomal dominant inheritance pattern…

A

Huntington’s

67
Q

Give an example of an X linked recessive condition…

A

Haemophilia A

68
Q

Name a condition caused by an aneuploidy…

A

Down syndrome, Turner, Edwards, Triple X, Klinefelter, XXY syndrome

69
Q

What are the causes and symtoms of Down syndrome?

A

Triploidy of chromosome 21, can be due to carrier parent (robertsonian translocation) or non disjunction at meiosis (I or II),
Symptoms- intellectual disability, hypothyroidism, heart disease, constipation, eye and hearing problems

70
Q

What causes Marfan’s syndrome and what are its symptoms?

A

Cause- genetic, mutation in fibrillin gene causing problems with elastin
Symptoms- arachnodactyly, abnormally tall, heart problems, lens dislocation

71
Q

What causes and what are the symptoms of Ehlers-Danlos syndrome?

A

Cause- genetic mutation affecting collagen (several different forms of the disease, affect different types of collagen)
Symptoms- stretchy skin, loose and flexible joints,