HIDS (or hyperimmunoglobulinemia D syndrome) is also known as Mevalonate Kinase Deficiency (MKD). It is a very rare autoinflammatory condition that usually starts in early childhood.[1-4] With HIDS/MKD, the blood levels of an antibody called immunoglobulin D (IgD) are higher than those in healthy people. But because there are other conditions where IgD levels are sometimes raised, measuring IgD is no longer considered the best way to confirm HIDS/MKD diagnosis.
HIDS/MKD usually becomes apparent in the first year of a child’s life. HIDS/MKD flares tend to occur every 2-8 weeks and last for 3-7 days  with symptoms including:[3,4,5]
HIDS/MKD flares can occur spontaneously or can be triggered by:
Image showing possible symptoms of HIDS/MKD[1, 3-4, 7-8]
It is still not clear what triggers the activation of the innate immune system in HIDS/MKD. However, it is known that those with HIDS/MKD have a mutation in the MVK (mevalonate kinase) gene, a protein involved in the production of cholesterol in the body.[1,7] This genetic change, which is thought to be the main underlying problem in HIDS, causes a drop in the levels of mevalonate kinase in the body. This deficiency creates a chain reaction that leads to an overproduction of cytokines, most prominently interleukin-1 beta (IL-1β). In fact, it has been suggested that the term “mevalonate kinase deficiency” should replace HIDS as the name of the condition.[9,10]
The change in the MVK gene is usually inherited from both mother and father in order to develop HIDS/MKD. However, some cases of HIDS/MKD have been reported in people who have inherited the altered gene from just one parent.
Hereditary transmission of HIDS/MKD
HIDS/MKD is a very rare autoinflammatory condition that usually starts in early childhood.[1-4] Only about 200 cases have been reported worldwide, although there are likely to be other affected people who remain undiagnosed. Among the known cases, Europeans are most commonly affected.
230 pages of patient stories and first hand experiences
Get advice to help you, if you know someone with a recurrent fever syndrome.
Read about the multifaceted burdens of rare autoinflammatory diseases.
Navigating rare autoinflammatory diseases: our commitment to you
Uncover the complexities of autoinflammatory diseases and learn how we are focused on helping individual through awareness, connection, community, progress and change.