When Jessica Kalnas was growing up, her mother Judy thought her daughter was just clumsy. The youngest of six kids, Jessica was always falling over: off of her bike, during field hockey practice, off of her school bleachers. It was the last fall that gave her mother worry and finally sent Jessica to a neurologist. However, her journey to diagnosis was difficult. Eventually, Jessica was diagnosed with late-onset Tay-Sachs disease. Her story not only gives insight into what this condition looks like, but into the importance of pushing for a diagnosis and advocating for better treatment within the rare disease community.
Tay-Sachs Disease
There is currently no cure for Tay-Sachs disease, a rare inherited lysosomal storage disorder. For patients with this progressive condition, they slowly lose bodily function as nerves in their brain and spinal cord are destroyed. The disorder results from HEXA gene mutations. With this mutation, fatty substances called gangliosides accumulate in the brain. As a result, tissue and cells are damaged.
Generally, Tay-Sachs disease affects infants and children. Commonly, symptoms begin to appear around 6 months old. Additionally, the disorder is usually fatal by age 5. However, in some rare cases, patients like Jessica develop late-onset Tay-Sachs disease (LOTS), which may not appear until adulthood. Symptoms include:
- Exaggerated startle response (infants)
- Low energy
- Floppy muscle tone
- Hearing and vision loss
- Loss of motor skills
- Changes in mood or personality
- Slurred speech
- Muscle stiffness and paralysis
- Seizures
- Difficulty with memory and comprehension
- Cherry-red spots in the eyes
- Dementia
Learn more about Tay-Sachs disease here.
Jessica’s Story
At age 14, Jessica’s family was concerned when they saw her crawling up steps on her hands and knees. Despite this worry, they trusted the teen when she stated that it was just a comfortable way of doing things. But by the following year, Jessica knew something was wrong. She couldn’t jump when she tried out for cheerleading, but worried that acknowledging it out loud would make it real; that telling her parents would be worrisome and disappointing. But while Jessica hoped her poor coordination would improve, her mother was already noting potential problems.
When Judy watched Jessica play field hockey, she wondered why her daughter didn’t run like the other team members. She later discovered that Jessica often fell during practice, worrying her coach. After she fell from the bleachers, citing weak knees, Jessica was referred to a neurologist.
Journey to Diagnosis
Duchenne muscular dystrophy (DMD), myasthenia gravis (MG), spinal muscular atrophy (SMA): these are three of the conditions Jessica was thought to have. But while her doctor ruled out DMD, and the medication for MG didn’t work, her new neurologist was confident that SMA was the cause of her worries. But after a worrisome MRI, when part of Jessica’s brain seemed to be shrinking, alarm bells were raised. Once again, she was referred to a new specialist, this time at the National Institutes of Health (NIH).
This referral proved to unlock the secret of Jessica’s condition. After months of genetic testing, Jessica was given a concrete diagnosis of late-onset Tay-Sachs disease (LOTS).
At first, Judy was confused. She wasn’t Jewish! Historically, Tay-Sachs disease is linked to Ashkenazi Jewish heritage. Around 1 in 27 people (3.7%) with Ashkenazi heritage are carriers for Tay-Sachs disease, around 10x more than the general population. But researchers now know that the disorder isn’t confined to one group of people. In fact, Tay-Sachs is also linked to people of French Canadian, Cajun, and Irish descent. Not only is the Kalnas family of Irish descent, but part of the family hailed from a Cajun-heavy area in Louisiana where Tay-Sachs disease was quite common.
Late-Onset Tay-Sachs Disease
Now, Jessica, 31, knows much more about her disorder and the diagnostic problems associated with it. Slightly under half of all patients experience psychiatric symptoms. Many doctors are unaware that LOTS even exists.
