I have had severe right flank pain for 8 months. No infection as all bloodwork has come back negative. I also have a red, itchy rash in both of my armpits. I m not sure if the two are related or if the flank pain is one thing and I am just allergic to a new deodorant I tried. I have switched deodorants back to something I am used to, but the rash is still there. Could the two be related. I have had an MRI , CT scan , and ultrasound and all appear normal, but this severe pain persists.