CDG stands for Congenital Disorders of Glycosylation.
CDG is the name of a group of extremely rare and complex genetic, metabolic diseases, which affects all parts of the body including the brain.
There are up to 50 different sub types and many more sub types are being identified by further research. There are several similarities between patients with CDG, but these can differ among sub types or even can be different for two patients with the same sub type. Some people are very mildly affected whereas others are severely affected with frequent hospitalisations. The types of symptoms associated with each sub type can be found here.
There are only approximately 1,000 cases diagnosed worldwide, with around 70 in the UK. Through the determined effort of geneticists, researchers, clinicians and parents, CDG awareness has expanded greatly since it was first medically recognized in the 1980’s, creating opportunities for earlier and more accurate diagnosis and for proper categorization of the existing CDG subtypes.
Despite increased understanding and awareness, the diagnosis of CDG can remain elusive. It is our belief that there remain many undiagnosed and misdiagnosed CDG patients, and that the true number of cases remains unknown. One of our goals is to raise awareness in the medical community about CDG, so that cases are diagnosed more quickly, and support can be offered to families earlier.
It is a very difficult condition to describe as the science behind it is so complex. However, in short, the enzymatic process of glycosylation is critical to normal organ development throughout the body. It seems especially critical for the development and maturation of the nervous system. Check out the video above for an easy-to-understand explanation of the causes of PMM2-CDG, the most common type of CDG. Many children remain unable to walk, talk or eat and are tube fed throughout their lives. Check out the community page to read CDG family stories. Unfortunately there is no treatment or cure. Sadly, we know of too many children who lost their battle to this awful disease.
Prognosis and Treatment
Some children with CDG have serious life-threatening medical problems during their infancy. Mortality in CDG IA children is about 20% during the first few years, but most CDG 1A children stabilize after childhood. Individuals with CDG require lifelong expert medical care from their team of physicians (usually comprised of geneticists, medical subspecialists and primary care).
Patients with CDG have varying degrees of physical and cognitive disability, including cognitive impairment (mild to severe), speech and language difficulties, poor balance and motor control. As children with CDG IA grow older, they may exhibit ongoing developmental impairment, vision problems, hearing impairment, seizure disorders, and stroke-like episodes.
However, many are highly interactive, some are conversational and universally they have very charming and winsome personalities. Most are wheelchair bound because it is easier and safer for them to get around as they have ataxic poorly coordinated movement patterns as well as muscular atrophy in their skeletal muscles and scoliosis of their spine.
Looking for a way to tell your other children about CDG? The Portuguese Association for CDG has created this little story about Ants to help them understand:
Prefer a pdf print out? The Hospital Sant Joan de Deu in Barcelona have created this explanation of CDG, which you may find useful:
See our resources page further information about symptoms, diagnosis, management and therapeutics, and support.