strange rash on thigh

[need_to_know1121]

I got a very strange rash about 2/3 of the way up my thigh in December of 2005. It started out as a very small cluster of about seven blisters... which expanded until they popped.  Sometime in the beginning stages of this rash, I noticed a little black dot in the center of each blister.  The black dots were only noticable in the late beginning/mid stages of the rash. The blisters start off more itchy (which I don't scratch) and end up more tender and painful. I was in South Florida when I first discovered the rash (I live in New England) so my Dr. assumed that it was something typical of south Florida which she was unaware of.  She gave me hydrocortizone and the rash went away, but left a scar.  About seven months later I got another outbreak of what appeared to be the same thing... in the same EXACT spot (and nowhere else). It was forming over the scar tissue from the previous rash.  This time it was minutely bigger.  I went to a different Dr. and he couldn't identify it.  He said that all he could tell me was that it didn't look like herpes and he ran some blood tests (which came back negative).  Since then I have been getting more outbreaks of this strange rash about every couple of months... always in the exact same spot.  Each time just a little bigger than the last.  My new Dr. said that there should be no reason for this, as I have very good skin everywhere else... please help.

[Alan Rockoff, MD]

Since it always comes back in roughly the same spot and produces blisters, I assume this is herpes.  The location suggests that it is genital herpes.  The way to diagnose it is to culture a blister when it's fresh, although a type-specific herpes 2 blood test can be done at any time, and is quite reliable.

I suggest you get these tests done as soon as practical.  If it turns out to be herpes, then depending on whether you have a regular sexual partner and other personal details you can learn about the best way to deal with the problem and what precautions to take.

Best.

Dr. Rockoff

[ryn21]

To my knowledge, HSV outbreaks occuring only on the leg and far from the genital region (on penis shaft or vaginal region) is rare but can happen.  Depending how long after your initial symptoms (DEC 05) you had your testing done depends on the accuracy of your result(most tests are 95%+ accurate (I believe somewhere between 6-14 weeks).  Type specific tests are necessary due to their ability to distinguish between HSV 1 and 2.  Type specific are more accurate as well.  You can get free testing at local free clinics.  Call your local health department for testing locations.  

IgG TESTING INFO

http://www.racoon.com/herpes/healthcheckusa_testing.htm

HERPESELECT INFO

http://www.questdiagnostics.com/hcp/topics/herpeselect/herpeselect.html