Painless rash on back of upper leg- what is it?

[samir]

Hi,

   Both my (soon to be ex-)boyfriend & I have a matching rash that has appeared in the last couple of months (M/F couple). It is flat, painless (slight occassional itching, hard to notice) red blotches on the inner back of our thighs (not directly between legs, back a little, hard to see unless you lift your leg sideways & look in the mirror). Both of our rashes our identical, neither has had this condition before. I just found out he that has had sexual contact with prostititutes (he says only oral sex with a condom, but my feeling is it's likely he's had vaginal sex too) during the last 15 months while we have been going out, so obviously I'm going for STD tests (was tested before meeting him/well after any other sexual partners- no STDs, he has no history of STDs either). I also have a compromised immune system (not HIV-related but similar issues) so I'm worried about catching random viruses etc.. that may be hard to eradicate. I noticed another online forum where perhaps 1/2 dozen people posted about a condition which seemed identical to ours, yet there were as many theories as to its nature as questions. I was hoping you could answer this for everyone, since it seems to be something specific?

  Additional (I think not related, but just in case) conditions I have include a strange foul smell/yellowish film or discharge in the inner thigh leg fold, I've been attributing to an ongoing yeast imbalance (which includes gastrointestinal/scalp yeast overgrowth) or possibly the fact that I have Crohn's type intestinal symptoms with previous problems of the lymph nodes in the groin area (not sure if that could be related to it or not), but I now realize that condition (the bad smell etc..) began after I began seeing this boyfriend & perhaps 2-3 months before the rash. Also I have strange tiny red dots on the skin of my arms, randomly spaced & very small, which itch occassionally, and are suspect only because they began about 3 years ago without changing/worsening since, after casual contact with a friend who (unknowingly) had scabies (over his entire body after travelling through Africa). Also, I get darkened heat(?) spots under my bust area which look different than the rash condition above & are painless (have had for about 10 yrs). Skin conditions for the (ex-)BF include a bumpy permanent rash (sorry I don't know the name of the condition) on the back of his arms (he's South Asian, raised in a tropical climate, was told this is common for his ethnicity/background by a dermatologist) and he has alopecia of the scalp. Otherwise no problems.

  Do you think this is an STD, heat rash, or something else? No bumps, just a red, blotchy, mostly unnoticable rash like a heat rash. Thanks for your help! I'm very happy to have found this forum, it's been very informative! :)

[ellie247]

A related discussion, Extremely dry spot on back of leg. was started.

[carmelyssa]

last night lying in bed the back and inner parts of my thigh were very itchy so I ignored it. but in the morning i noticed that when i got dressed that the rash looked like little red pimples. but there not anywhere else on my body  

[Alan Rockoff, MD]

This does not sound like an STD.  It is more likely to be a heat rash or irritation of some sort.  There is, however, no way to tell you definitively what is is without seeing it.  Since you plan to be tested for STD's anyway, you ought to show the rash to the doctors who do the test when you go.  As to the discharge, that needs to be looked at too, and perhaps tested, as it is likely to be either yeast or just a friction rash.

Best.

Dr. Rockoff