What Causes A Purple Rash On The Buttock?

Posted on Mon, 5 Dec 2016

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Mon, 5 Dec 2016 Answered on

Wed, 28 Dec 2016 Last reviewed on

Question : I have a deep purple color rash on upper right side of buttock near crack. It is itchy and seems to be raised.

Answered by Dr. Dr. Kakkar (14 minutes later)

Brief Answer:
Need more information

Detailed Answer:
Hello. Thank you for writing to us

I am dr.kakkar(dermatologist). I have gone through the query abd i have reviewed the image.
I would keep a possibility of either Herpes Zoster or Insect bite hypersensitivity. I request you to kindly upload a few more images so that i am able to confirm.
Also let me know that do you also have pain?burning sensation?

Regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Dr. Kakkar (18 hours later)

I have attached 2 more photos that I took this morning. Yes there is some minor pain, the area is very tender. Also I guess you could describe it as a slight burning sensation along with itching.

Answered by Dr. Dr. Kakkar (6 hours later)

Brief Answer:
Need information on concurrent medical history/ treatment

Detailed Answer:
Hi.

Topically you may use a topical antibacterial ointment e.g Mupirocin ointment or Neosporin ointment, twice daily.

The recent Images show that it has spread and become confluent. Herpes zoster is a possibility, however I would also like keep another differential diagnosis of Retiform Purpura.

I would like to know whether are you on some other medical treatment ? on any anticoagulants like warfarin or heparin ?

Awaiting

Regards

Above answer was peer-reviewed by : Dr. Arnab Banerjee

Follow up: Dr. Dr. Kakkar (17 minutes later)

No I am not on any anticoagulants. I take 81mg aspirin once daily.

Answered by Dr. Dr. Kakkar (9 minutes later)

Brief Answer:
Likely herpes zoster

Detailed Answer:
Thank you.

Herpes zoster S 2 or S 3 dermatome is the most likely diagnosis.

I would suggest an Oral antiviral e.g Valacyclovir 1gm, 3x daily for a week(Please obtain the necessary prescription from your local physician).
Topically you may use antibacterial ointment as already mentioned.

Regards

Above answer was peer-reviewed by : Dr. Arnab Banerjee

Follow up: Dr. Dr. Kakkar (21 minutes later)

Thank you I just made an appointment with my doctor for Friday.

Answered by Dr. Dr. Kakkar (5 hours later)

Brief Answer:
You are welcome

Detailed Answer:
Thank you for writing to us. You can get back to me for any assistance.

Regards

Above answer was peer-reviewed by : Dr. Nagamani Ng