Brief Answer:
It's a misnomer

Detailed Answer:
Welcome to Healthcaremagic.

Hi, I am Dr Anshul Varshney , I have read your query in detail , I understand your concern.

Spider bite never causes leukemia, and this is actually a misnomer.

You find bruises, rashes and enlarged lymph nodes in a person suffering from leukemia due to low platelet count.

A spider bite can also cause the same picture in absence of any leukemia.

So, this is the reason, spider bite has leukemia like reaction and some people call it as spider bite leukemia.

This is my personal opinion based on details available here. If you still have any other query, you may please ask me.
Stay Healthy.
Dr Anshul Varshney , MD

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