Strange bumps on arm turned in to blistery rash

[skramey08]

I noticed 3 bumps on my left arm one day, & I had no idea where they came from. They were raised in a triangle shape, were skin colored & didn't itch. The top bump of the triangle had a little brown mark on it, so I thought maybe it was a bite & the mark was a puncture spot. Over the next couple of days, the bumps started to itch & spread. Eventually the raised bumps formed a horseshoe shape & looked like they were going to pop out of my arm. They became itchier & itchier, but I tried not to scratch. After first thinking it was a bite, I eventually worried about ringworm & shingles (I had chicken pox when I was 17) because of the different ways my arms was beginning to look. I know it's not ringworm because a definite red ring never formed, & I am not totally sure whether or not it's shingles. It's only on my left forearm, & eventually formed a blister. The blister has popped, reformed, & popped again. Once the bumps formed the u-shape, the area became slightly painful & still just as itchy. Now it's not painful, but still itches. I've tried EVERYTHING from Claritin, Benadryl, Lotrimin powder spray, Lamisil powder spray, antiobiotic ointments, baking soda paste, peroxide, apple cider vinegar, calamine lotion, & antibacterial soap & water. My skin became pretty tight, so I applied some vitamin e, & instantly, a thin layer of the affected area of skin peeled off, & I got a little relief as far as the itching & tightness. Of all the things I've tried, the antifungal sprays & calamine seem to provide the most relief. Warm water & antibiotic ointments seems to really irritate the area, & everything else I listed just didn't work. I don't have insurance, so I went to the pharmacy to see the pharmacist, & she thinks it might be a bite. Prior to the outbreak, I was taking bactrim, so could this also be an allergic reaction? I'm completely puzzled. What could this be? Pics of the progression are under my profile photos, please refer to them if you will before responding.

[skramey08]

I have not developed new lesions, in fact, my arm appears to be healing. Since I do not have insurance, I am just going to hope that this never happens again and chalk it up to a mystery. I still do not know what it was or what happened, but since my arm is clearing up, I guess I have to leave it at that. Thanks...

[Jasmina Jankicevic, MD, MSc, CCRP]

Welcome to the Dermatology Expert Forum!

Shingles, as well as Impetigo bullosa and even reaction to insect bites, have a bit different clinical manifestations from what you described but should be considered.

If drug induced, localized skin lesions, should completely resolve after discontinued use of a causative drug. Treatment with topical corticosteroids may promote healing process.

However, grouped, small, tight blisters filled with clear fluid (no pus in later stages), positioned on skin-colored to slightly erythematous (red) skin accompanied with intense itch require evaluation by a physician who should exclude autoimmune bullous dermatoses such as Dermatitis herpetiformis-Duhring, Pemphigoid bullosus, etc, especially if you continue to develop new lesions.

Wishing You Optimal Health,
Dr. Jasmina Jankicevic