Caused by mistakes in genes, a child can only develop Sanfilippo syndrome if they inherit mutations in one of four different genes from both parents.
Classical symptoms typically begin to show around the age of five and can present as difficulties or delayed development in talking, reading, writing, walking and playing. This is followed by a progressive intellectual and bodily decline until the child usually passes away by their late teens or early 20s.
“The parents largely have no idea the risk of Sanfilippo is even in their family,” Professor Hemsley says.
“This is one of the main drivers for having newborn screening for this and similar disorders, because parents at the moment don’t realise that they have a child with Sanfilippo until symptoms develop and they are diagnosed.”
Over the past 20 years the Childhood Dementia Research Group – which was established at the Adelaide Women’s and Children’s Hospital before moving to the South Australian Health and Medical Research Institute – has made several significant contributions to the disease.
These include working with a large team of medical researchers in Adelaide and overseas to develop treatments; some failed, but some have provided important and promising outcomes.
One approach appears to stabilise disease in patients treated before two-and-a-half years of age.
Professor Hemsley says while we are nearing a time when the first treatment will be approved for children with Sanfilippo, it won’t mean her work is done.
“One treatment will not be enough as many children will be unable to access it because of medical reasons as well as geographic and financial ones,” she says.
“So, with our collaborators, we are continuing to devise and test potential therapies for Sanfilippo and other childhood dementias to ensure that one day all children born with the disorder can be offered safe and effective treatment.”
Finding a ray of hope for families is what compels Professor Hemsley to keep striving for answers.
Unlike many neuroscientists, her research sees her interact not only with clinicians but also the children and their families — often the strongest advocates for awareness.
“It’s heartbreaking watching the children disappear before your eyes,” Professor Hemsley says.
“It’s hard to imagine how families who have Sanfilippo deal with it day in and day out. They’re absolute heroes.
“It’s quite a unique field and I feel very lucky to be involved. That interaction is most definitely what keeps me here.”