M4 IM

Question 1

When is post-op PSA measured after prostatectomy for prostate CA?

Answer 1

Usu after 4-8 weeks cuz some PSA can remain in blood for a while after the op.

Question 2

How to test for ketones?

3 types of ketones!!

Answer 2

3 types of ketones = BHOB, acetoacetate, acetone.
Only BHOB can be sensed in blood, the other 2 only seen in urine.

Even if urine tests are neg, u still gotta test for blood.
Cuz BHOB in blood is the first ketone to rise and is the first to get cleared.

Question 3

2 types of L-type Lactic acidosis?

Answer 3

Type A = obvious tissue hypoxia. There is:
- severe hypoxia
- severe anaemia
- shock/haem
- CCF

Type B = tissue lactic acidosis. No obv hypoxia.
- Acquired disease e.g. DM, Liver failure, tumours
- drug, toxins
- congenital disorders e.g. enzyme deficiency

Question 4

What to suspect if anion gap + osmolal gap both high?

Answer 4

Methanol
DKA
Alcoholic KA
Chronic renal failure

Question 5

What does HAGMA mean clinically?

Answer 5

HAGMA is an index of unmeasured osmoles, mainly ethanol, methanol and stuff.

Question 6

formula for Calculated Osmolality?

Answer 6

2x Na + Glucose + Urea

Question 7

Does HR always increase after BP drops ?

Answer 7

Failure of HR to rise after BP falls points to autonomic pathology or BB use.
Exaggerated HR points to hypovolemia.

Question 8

What can circulating paraprotein in paraproteinemia cause?

Answer 8

1. Hyperviscosity -> arterial / retinal bleeds
2. Inhibit or raise clearance of F7 and vWF causing acquired vWF disease
3. Impair platelet aggregation
4. Inhibit fibrin polymerization
5. Have heparin-like anticoag function that can be reversed by protamine.

Question 9

Causes of abnormal T protein?

Answer 9

Low = Malnutrition, low GI absorption, reduced production, increased loss
High = Dehydration, prolonged tourniquet, increased globulin due to: infection, inflammatory disease, immune disorder
TRO Multiple Myeloma, Hodgkin lymphoma or malignant lymphoma in high T protein.

Question 10

Where is ALP made?

Answer 10

Liver, bone, 3rd trimester placenta, intestines

Question 11

Causes of elevated ALP?

Answer 11

Biliary = intrahepatic cholestasis, extrahepatic biliary obstruction
Hepatic = non-specific e.g. hepatitis cirrhosis, hypoperfusion states
Non-hepatic cause with normal GGT = physiological in children or pregnancy, influx of intestinal ALP
High bone turnover -> healing fracs, hyperPTH, osteosarcoma

Question 12

Tell me about PSA

Answer 12

It is a glycoproteoin made in prostate. Most men without prostatic Ca have PSD <4ng/ml in blood.

PSA has T-half of 2-3 days

Question 13

CAuses of raised PSA?

Answer 13

BPH
Age
Prostatitis
Ejaculation
Riding bicycle

Question 14

Causes of lowered PSA?

Answer 14

5-Alpha reductase inhibitors
Herbal mixtures and meds

Question 15

How to monitor prostatic cancer after surgery?

Answer 15

Estimating PSA doubling time in known prostate Ca post-treatment predicts mortality, relapse and guides treatment decisions.

> 1 year = 10% 5 year mortality
Up to 1 year = 50% 5 year mortality
<3 months = 5 year mortality 20x higher

An alternative method is PSA velocity. Rate of rise needs 3 separate PSA measurements over min 18 months. Yearly rise of >0.75 ng/ml or >25% is considered significant.

Question 16

What is Biochemical Recurrence (BCR) of prostatic Ca?

Answer 16

After radical prostatectomy = PSA >0.4 ng/ml and rising
After primary radiotherapy = Rise in PSA > 2 ng/ml than nadir

PSA nadir is the lowest level that the PSA drops to post treatment

Question 17

Unfavourable prognostic factors after radical prostatectomy?

Answer 17

PSA doubling time less than 1 year and final Gleason score of 8-10

Question 18

Unfavourable prognostic factors after primary radiotherapy?

Answer 18

Interval to biochemical failure <18 months and biopsy bGS of 8-10