MVK and hyperimmunoglobulinemia D with periodic fever: In HIDS patients residual enzyme activity of MVK is reduced to 1-8%, so the metabolic pathway of steroids synthesis induces lower levels of serum cholesterol, higher urinary excretion of mevalonic acid and higher activity of hydroxy-metil-coA reductase (HMG-coA) for the shunt of metabolic precursors towards the synthesis of pro-inflammatory isoprenoids [17].