The invention provides compositions and methods for the treatment of glomerulonephritis. In one embodiment, the invention provides a compound of formula (I) R-L-CO—X  (I) (wherein R is a C10-24 unsaturated hydrocarbon group optionally interrupted by one or more heteroatoms or groups of heteroatoms selected from S, O, N, SO, SO2, said hydrocarbon group comprising at least 4 non-conjugated double bonds; L is a linking group forming a bridge of 1 to 5 atoms between the R group and the carbonyl CO; and X is an electron withdrawing group) or a salt thereof for use in the treatment of glomerulonephritis.