If you missed our discussion on heparin,
please make sure that you refer to our hematology hemodynamic pharmacology
where I talked about in great detail the possibility when given heparin at the site of injection
where there's a possibility in sub-set of population
in which may then activate the platelet via platelet factor IV.
And by doing so, you may then form a thrombi formation and result in thrombocytopenia.
Other causes, quinidine class 1A sodium-channel blocker, sulphas, methyldopa.
That'll be in alpha 2 agonist that you may then give a pregnant lady who has hypertension prior,
was on ACE inhibitor, obviously, needs to remove that, right?
Because ACE inhibitor will kill the kidneys of the fetus or teratogen.
And unfortunate the patient may then develop thrombocytopenia.
Also penicillins and also thiazide diuretics.
This is important.
So now you have antibodies formed against HIV antigen.
The gp120 cross-react with the platelet surface antigen.
In other words, we have example of molecular mimicry of IIb/IIIa.
And now what happens is the antibodies bind to the platelet which are then cleared by the spleen.
The particular antigen or chemokine that you wanna know that allows for entry of HIV in the platelet,
if you remember from microbiology it's called CXCR4.
Keep that in mind please.
But at this point, in pathology with HIV, take a look at molecular mimicry with gp120
if you remember that from your HIV discussion.