I have a scaly rash on my chest and a welt like bump on my leg. ive had both for a while. i also have been dealing with palpable lymph nodes near my collarbone and armpit with no known cause. could this all be related?

I'm uncertain whether these are all interrelated, but I'd ask for a diagnosis of the rash by a dermatologist. I assume blood work has ruled out leukemia & infectious mononucleosis. I would also ask a surgeon to perform a lymph node biopsy to get a definitive answer of the significance of such widespread lymphadenopathy. He/she can also examine the bump on your keg.