HAMP and lupus nephritis: Using low molecular weight proteome to predict impending renal relapse, relapse severity, and the potential for recovery after SLE nephritis flare, it was observed that hepcidin 20 (isoform of hepcidin that lacks the first five amino acids of the amino-terminal portion) increased 4 months before renal flare and returned to baseline during renal flare, whereas hepcidin 25 decreased during renal flare and returned to baseline 4 months after the flare (134).