Nodding syndrome mystery hangs on

Children with nodding syndrome

What you need to know:

  • Understanding the changes in the nodding syndrome brain may also contribute to our understanding of Alzheimer’s disease and related conditions.
  • The mystery of nodding syndrome in East Africa remains unsolved. We are committed to continued research on nodding syndrome.

Our work shows that nodding syndrome in northern Uganda is a form of neurodegeneration that involves the protein called tau. This protein is normally present in the brain, but it becomes abnormally folded in the brain cells of the children with nodding syndrome. The abnormal protein then accumulates in the brain.
On this basis, nodding syndrome now joins the larger group of disorders called the tauopathies. Most tauopathies affect adults or the elderly people and result in dementia or parkinsonism. The most common example is Alzheimer’s disease.

The causes of the different forms of tauopathy are not completely known. The relationship between the tauopathy in nodding syndrome and onchocerciasis is unclear. It is an open question if onchocerciasis can cause the tau-related neurodegeneration in nodding syndrome. Our continued research will explore the possible relationship, if any, of the nodding syndrome tauopathy and onchocerciasis.

In addition, we will also explore the alternate hypothesis that nodding syndrome is a newly recognised neurodegenerative disease. This may have implications for understanding the cause of other neurodegenerative disorders. Specifically, because nodding syndrome is present in geographic foci in East Africa, understanding how nodding syndrome develops may shed light on how other neurodegenerative diseases (eg Alzheimer’s disease and related conditions) develop in other communities.

Furthermore, the presence of geographic foci of nodding syndrome in East Africa is reminiscent of the Pacific foci of the amyotrophic lateral sclerosis/Parkinson’s and dementia complex (ALS/PDC) that occurred on the island of Guam, the Kii peninsula in Japan and in New Guinea. Although ALS/PDC and nodding syndrome are different and unrelated diseases they both emerged in indigenous communities and both represent disorders with prominent neurodegeneration.

The mystery of nodding syndrome in East Africa remains unsolved. We are committed to continued research on nodding syndrome. We believe that our discovery of abnormal tau proteins in nodding syndrome provide a new line of research inquiry that may catalyse important new research efforts.
These efforts could lead to identifying the cause of nodding syndrome and an effective cure or treatment. Furthermore, understanding the changes in the nodding syndrome brain may also contribute to our understanding of Alzheimer’s disease and related conditions.
Dr Sylvester Onzivua,
Mulago National Referral
Hospital, Kampala-Uganda