I Have Developed A Severe Itchiness, Bumpiness, And Scaling On

I have developed a severe itchiness, bumpiness, and scaling on my hands and multiple rashes on my body in various places. My hands are very swollen and red. I have tried changing soaps, detergents, lotions. I have had steroid shots and creams. I have tried light therapy. I have been diagnosed with eczema, psoriasis, and dermatographia. None of the treatments for any of this has helped in any way. What is my next step? BTW-Have seen 4 different dermatologists including Mayo among others.