It's been a long since this post, anyway I just found this paper talking about the sarcoid granuloma in black tatoos. Unfortunately, I also have those lumps in a tatoo I had done 4 years ago... at the beggining it was just so itchy and now the lumps are horrible.
Apparently the allergy to the metals found in the ink might be the cause.
I wanted to ask if you could get rid of them?
https://www.sciencedirect.com/science/article/abs/pii/S0190962205049467