Hello,
Thanks for posting your query.
Development of large purple bruises on back of your knee spontaneously without any history of injury is suggestive of a bleeding disorder. In some cases, prolonged intake of drugs like aspirin can also cause this.
You need to consult your physician to get a complete blood coagulation profile checked with APTT and platelet count to rule out other possible causes like thrombocytopenia.
This can also happen due to a viral infection in the recent past- decreases the synthesis of platelets from the bone marrow.
Presence of any autoimmune disorders also needs to be ruled out.
The treatment is based on the diagnosis and severity of the problem. Treatment is usually done by stopping aspirin, fluid infusion, steroids, immunoglobulins, blood transfusions, etc according to the severity of the condition.

Hope this answers your query. I will be glad to answer the follow up queries that you have.
Please accept my answer in case you do not have further queries.
Wishing you good health.
Regards.
Dr. Rakhi Tayal.

---

Hello.

Thanks for writing again.
7-Keto is not likely to cause the spontaneous appearance of bruise that you are having.
I would suggest that you undergo a complete blood workup including a platelet count, bleeding time , aPTT . Also, a complete physical check up by your physician would prove useful
Hope this answer is helpful.

Do accept the answer in case there are no further queries.

Regards.

---