Kenneth Glad
Just days before turning two, Leni Forrester was diagnosed with Sanfilippo syndrome, a condition so rare and subtle in its early stages that it often escapes detection until damage has already begun. Her case is drawing attention not only because of its severity, but because of how little time families may have to respond once the condition is identified.
Sanfilippo syndrome is a genetic disorder that stops the body from breaking down certain sugars, leading to a gradual buildup of toxic material in the brain. Over time, this causes irreversible neurological decline.
The Cleveland Clinic reports that the disease typically leads to worsening cognitive and physical symptoms, with life expectancy often limited to the early teens. It affects an estimated 1 in 50,000 to 250,000 births.
Research into treatment is ongoing. ITV News has highlighted experimental gene therapy being developed at the University of Edinburgh, where Professor Brian Bigger and his team are working to replace the faulty gene.
“We’re racing against time,” Bigger said, noting that once brain cells are lost, recovery is not possible. Early-stage patients are therefore the most likely to benefit from emerging therapies.
Diagnosis challenge
Detecting the condition early remains difficult. In many cases, children show no clear symptoms in infancy, which can delay both diagnosis and access to trials or experimental care.
For Leni, testing was only pursued after a relative was identified as a carrier, according to The Mirror. Even then, initial screening suggested no immediate issue before more detailed analysis confirmed the disorder.
Her mother, Emily, told ITV News that the signs were easy to overlook. “We didn’t have any concerns at all about Leni,” she said, describing her as “sunshine.”
Looking back, she said the small physical traits they noticed did not appear medically significant within the family context. “Both me and my husband have bushy eyebrows, so it’s not that unusual,” she explained.
A critical period
Now, the focus has shifted to securing treatment as early as possible. Delays could mean losing abilities that cannot be regained.
Emily described how quickly the condition can advance, explaining that harmful substances continue to accumulate in the body without intervention. She told ITV News: “All your dreams for your child’s future are taken away. It is every parent’s worst nightmare.”
The family has launched a GoFundMe campaign to try to access experimental therapy. She emphasized the importance of timing, saying early intervention offers the best chance of preserving development.
For families like Leni’s, the challenge is not only finding treatment, but doing so before the disease progresses beyond the point where help is possible.
Sources: The Mirror, ITV News, Cleveland Clinic, GoFundMe
