The clinical picture of HIDS is believed to reflect enhanced proinflammatory cytokine production by mononuclear cells.[4] A defect in apoptosis of lymphocytes has also been detected.[5] The proinflammatory state, with resultant overproduction of tumor necrosis factor alpha (TNF-α) and interleukin 1-beta (IL1β), is believed to induce the disease's characteristic attacks.[3]. Here, TNF is linked to mevalonic aciduria.