From despair to determination: the impact of early SMA testing

Spinal muscular atrophy (SMA) is a severe, progressive neuromuscular disorder due to genetic mutations or deletions of the SMN1 gene. Patients present as “floppy infants” with early onset of muscle weakness, failure to achieve motor milestones, and limited survival without ventilatory support in the most severe cases. The recent introduction of disease-modifying treatments has greatly improved the survival and motor development of children with SMA.
 

The importance of early diagnosis 

The current standard of care in the NHS requires a genetic test result for SMA within 14 days. However, with the emergence of the new treatments for SMA, which give the greatest benefits to the children when initiated as early as possible, faster diagnosis of SMA has become very important for the best outcome. In collaboration with the clinical genetics team, we at Synnovis Monogenics Laboratory have developed a new genetic test to rapidly diagnose SMA using a technique called digital PCR (dPCR), which allows us to provide an accurate result in just 1 to 2 days. 

Noah was born in 2016 after an uneventful pregnancy. Juliet and her partner were delighted with baby Noah, their fourth child and only boy, who was very quiet. 

When Noah was 5 weeks old, he caught a cold which he struggled to recover from. This led him to requiring ventilation and intubation over Christmas, at a specialist hospital hundreds of miles away from their home. It was tough going for the family and they were delighted when they were able to bring baby Noah home in the New Year.

However, Juliet noticed that Noah could not hold his head up and he couldn’t lift his dummy to his mouth. After seeing several health-care professionals things came to a head when Juliet cried at an appointment and explained how different Noah was to other babies of the same age. His breathing pattern was different and his legs had now stopped moving altogether. This led to a referral to a specialist who suggested Spinal Muscular Atrophy (SMA) and genetic testing which could take up to 2 weeks. At 4 months of age, Noah was diagnosed with SMA type 1 (the most severe form) by our laboratory.

For Rare Disease Day, Juliet kindly gave an interview about her experience of SMA diagnostic testing and how the new rapid dPCR SMA test will have a positive impact for the lives of families affected by SMA. Juliet was interviewed by Dr Deborah Ruddy, the Clinical Director of the NHS South East Genomic Laboratory Hub and Dr Cheryl Walsh, Deputy for the Monogenics laboratory in Synnovis.
 

The agonising wait for diagnosis

Juliet remembered how agonising and difficult it was for her family whilst they were waiting for Noah’s genetic test result. It was constantly on their mind and Google was used a lot, which tended to give worrying information and a poor prognosis. In addition, Juliet could see how Noah deteriorated every day whilst they were waiting for his diagnosis. At that time SMA treatments were in their earliest days. Therefore, when the diagnosis was obtained, it was difficult to access treatment and unfortunately, when Noah was waiting to be treated with Spinraza®, he caught a cold which left him severely ill, in intensive care on a ventilator. Children affected with SMA require extra care when they have colds as they cannot cough strongly enough to remove mucus from their lungs and so develop worse breathing problems, making it hard to remove the need for ventilation. Fortunately, after a delay Noah recovered enough to be treated, and he received Spinraza® when he was five months old. 

There are several different SMA treatments available now. They do not reverse symptoms, they can only stop further deterioration from the disease. The earlier they are given, the better: every day counts. Noah is now 8 years old, loves swimming and goes to mainstream school. He drives a power chair and is peg fed, as he can no longer swallow.
 

A brighter future with rapid testing

From now on, the rapid dPCR SMA test available at Synnovis will significantly reduce the agonising wait for families awaiting the result of their SMA test. In particular, for patients whose samples arrive at the laboratory at the end of the week, the parents will not have to wait over the weekend. For those families diagnosed in the future with SMA, this test will significantly cut down the time waiting for treatment, reduce the anxiety, and improve the future quality of life for the patients.
 

With special thanks to Noah and Juliet, and also to Dr Deborah Ruddy, Clinical Director of the NHS South East Genomic Laboratory Hub; Dr Cheryl Walsh, Deputy for the Monogenics laboratory in Synnovis. The rapid SMA assay was developed by Dr Cheryl Walsh, Katrina Newland Pre-registration Scientist in Monogenics at Synnovis and Dr Michael Yau, Lead Scientist for Rare Disease Genomics, NHS South East Genomic Laboratory Hub.