tPA derivatives vs Streptokinase
How to tell tPA derivatives and Streptokinase apart when a board question makes them look alike.
tPA is recombinant and relatively fibrin-specific; streptokinase is antigenic and more systemic.
Side by side
Alteplase-like recombinant plasminogen activator with relative fibrin specificity, used for eligible acute ischemic stroke, STEMI, or massive PE.
Streptococcal-derived fibrinolytic that activates plasminogen more systemically and can be antigenic with allergy or neutralizing antibody concerns.
tPA derivatives convert fibrin-bound plasminogen to plasmin at the clot surface.
Streptokinase forms a complex with plasminogen and promotes systemic plasmin generation.
Eligible acute ischemic stroke wording and fibrin-specific recombinant activator point to alteplase/tPA derivatives.
Prior streptococcal exposure, allergy, or non-fibrin-specific systemic fibrinolysis points to streptokinase.
The trap
Both generate plasmin from plasminogen and both cause bleeding, but they differ in fibrin specificity, antigenicity, and reusability. tPA derivatives (alteplase, reteplase, tenecteplase) are recombinant human enzymes that preferentially activate fibrin-bound plasminogen, are not antigenic, and can be re-dosed; first-line for acute ischemic stroke within 4.5 hours and for STEMI when PCI is unavailable. Streptokinase is a bacterial protein that activates circulating plasminogen non-specifically, is antigenic (prior streptococcal exposure produces neutralizing antibodies), can cause hypersensitivity reactions, and cannot be re-administered within 6 months; rarely used in modern practice but still appears on USMLE for mechanism.
The repair move
For fibrinolytics, separate shared bleeding risk from fibrin specificity and antigenicity.
Try a free question
CoreA patient with eligible acute ischemic stroke receives recombinant tissue plasminogen activator to convert fibrin-bound plasminogen into plasmin. Which agent best fits?
Show answer and explanation
Answer: A. Alteplase. Alteplase is recombinant tissue plasminogen activator and is relatively fibrin-specific compared with streptokinase.
Why the other choices are tempting
- B. Streptokinase forms a complex that activates plasminogen more systemically and is antigenic.
- C. Heparin prevents clot propagation but does not lyse fibrin directly.
- D. Aspirin inhibits platelet thromboxane production.
- E. Warfarin reduces vitamin K-dependent factor activity and does not lyse clots.
Flashcards
Tap a card to flip it.
What is the fastest separator for tPA derivatives vs Streptokinase?
tPA is recombinant and relatively fibrin-specific; streptokinase is antigenic and more systemic.
What clue should make you choose tPA derivatives?
Alteplase-like recombinant plasminogen activator with relative fibrin specificity, used for eligible acute ischemic stroke, STEMI, or massive PE.
Quick answers
What is the fastest way to tell tPA derivatives from Streptokinase?
tPA is recombinant and relatively fibrin-specific; streptokinase is antigenic and more systemic.
What is the key clue for tPA derivatives?
Alteplase-like recombinant plasminogen activator with relative fibrin specificity, used for eligible acute ischemic stroke, STEMI, or massive PE.
What is the key clue for Streptokinase?
Streptococcal-derived fibrinolytic that activates plasminogen more systemically and can be antigenic with allergy or neutralizing antibody concerns.
What is the common trap with tPA derivatives vs Streptokinase?
Both generate plasmin from plasminogen and both cause bleeding, but they differ in fibrin specificity, antigenicity, and reusability. tPA derivatives (alteplase, reteplase, tenecteplase) are recombinant human enzymes that preferentially activate fibrin-bound plasminogen, are not antigenic, and can be re-dosed; first-line for acute ischemic stroke within 4.5 hours and for STEMI when PCI is unavailable. Streptokinase is a bacterial protein that activates circulating plasminogen non-specifically, is antigenic (prior streptococcal exposure produces neutralizing antibodies), can cause hypersensitivity reactions, and cannot be re-administered within 6 months; rarely used in modern practice but still appears on USMLE for mechanism.