Question

A patient underwent thrombectomy of femoro popliteal segment with poor outflow and was on heparin infusion. His platelet count dropped from 2 lakhs to 1 lakh/mm$^3$ on 6th day of infusion. Other blood parameters were normal and there was no feature of sepsis/infection.
What is the likely cause of this condition?

Hint:

HIT typically occurs after 5-10 days of heparin therapy. A significant drop in platelet count after this period should raise suspicion of HIT.

Answer 1

Step 1: Understanding the patient's presentation.
The patient presents with a significant drop in platelet count (thrombocytopeni after being on heparin infusion. This drop, occurring on the 6th day of treatment, with no signs of infection or sepsis, strongly suggests Heparin-induced thrombocytopenia (HIT). HIT is a known complication of heparin therapy, where the body forms antibodies against heparin-bound platelet factor 4 (PF4), leading to platelet activation and consumption. This results in thrombocytopenia, and in some cases, an increased risk of thromboembolic events.

Step 2: Conclusion.
The most likely cause of this patient's thrombocytopenia is Heparin-induced thrombocytopenia (HIT).