Tyler Hart's medical journey began with a series of perplexing symptoms that left him and his doctors searching for answers. For over a decade, Tyler was diagnosed with chronic inflammatory demyelinating polyneuropathy (CIDP), a condition that led to numerous treatments but no significant improvement. It wasn't until he sought a second opinion at Mayo Clinic that he finally received the correct diagnosis of neurofascin 155-IgG4 autoimmune nodopathy (NF155-IgG4 AN).

Early symptoms and misdiagnosis

Tyler's symptoms started in his teenage years with weakness in his hands and feet, and a gradual loss of motor function. Initially misdiagnosed with CIDP, Tyler underwent various treatments, including IVIG infusions and immunosuppressive therapies. Despite these efforts, his condition continued to worsen, leading to significant weakness and disability.

Reflecting on his journey, Tyler said, "I was realistic with my diagnosis. If I can just maintain and maybe get a little better here and there, I guess I'm happy with that."

The misdiagnosis was not due to negligence but rather the limitations of medical knowledge and testing available at the time. Div Dubey, M.B.B.S., a neurologist and co-director of the Neuroimmunology Laboratory in Mayo Clinic’s Department of Laboratory Medicine and Pathology (DLMP) emphasized:

"Had I seen Tyler in 2013, I would have done the exact same thing that other doctors did. The advancements that DLMP and Mayo Clinic Laboratories have made in medical testing since then have been crucial in properly identifying these rare conditions."

Journey to Mayo Clinic

In March of 2023, Tyler decided to seek a second opinion at Mayo Clinic. He was referred to Dr. Dubey, a specialist in peripheral nerve disorders. Dr. Dubey's expertise and the availability of the advanced diagnostic tests performed by DLMP and Mayo Clinic Laboratories played a crucial role in identifying the true cause of Tyler's symptoms.

“Tyler’s case was complex, and the symptoms he presented made me suspect an autoimmune nodopathy,” Dr. Dubey says. “The combination of tremors, speech changes, the pattern of weakness, and the limited response to IVIG were red flags that led us to test for neurofascin 155-IgG4 antibodies."

Correct diagnosis and treatment

After meeting with and examining Tyler, Dr. Dubey ordered Mayo Clinic Laboratories’ test for neurofascin 155-IgG4 antibodies, which confirmed his diagnosis. This breakthrough allowed Tyler to switch to a more effective treatment: rituximab. Since starting this new therapy, Tyler has shown signs of improvement, with reduced symptoms and a better quality of life.

"The diagnosis was actually hopeful because I was able to stop my weekly infusions and switch to rituximab every six months," Tyler says. "It's been a good thing for me, and I haven't seen any side effects hardly at all."

Dr. Dubey added, "We are hopeful that with continued treatment, Tyler will see more improvement. The early signs are promising, and we aim to stop the progression of the disease and help him regain as much function as possible."

Understanding NF155-IgG4 autoimmune nodopathy

Neurofascin 155-IgG4 autoimmune nodopathy (NF155-IgG4 AN) is a rare autoimmune disorder affecting the peripheral nerves, leading to demyelination and neurological symptoms. A recent study from Mayo Clinic demonstrated that the pediatric patients often present with rapid progression of symptoms, including distal predominant weakness, paresthesias, and sometimes tremors or cerebellar ataxia. Sensory ataxia is less common in children compared to adults.

Properly diagnosing NF155-IgG4 AN involves testing for NF155-IgG4 antibodies, often by using a live cell-based assay. MRI and CSF analysis can also aid in diagnosis. Pediatric patients are often refractory to IVIG but respond well to rituximab, an immunotherapy. Early initiation of rituximab is associated with better outcomes. Most pediatric patients show significant improvement with immunotherapy, particularly rituximab, and can achieve favorable outcomes with reduced disability scores.

Impact on daily life

Receiving the correct diagnosis and treatment from Mayo Clinic has had a profound impact on Tyler's daily life. As a multi-craft maintenance technician at 3M in Alexandria, Minnesota, Tyler's work involves building and maintaining machines, a task that requires fine motor skills. The improvement he’s experienced in his condition since his diagnosis has allowed him to continue working and pursuing hobbies like working on his classic cars.

"I work with my hands quite often, both at work and in my hobbies," Tyler says. "Improving my fine motor skills is really important to me. I've got good strength, but fine motor skills are complicated."

Tyler's classic cars collection includes a 1949 Chevrolet and 1970 C10, which he enjoys restoring and maintaining. "I've always loved cars, which led me to find a career in the automotive industry,” he says. The ability to continue working and engaging in his hobbies has been a significant boost to Tyler's morale. "Being able to do what I love and not be limited by my condition is incredibly important to me," he said. "It gives me a sense of normalcy and purpose."

Support system

Throughout his diagnostic journey, Tyler has received unwavering support from his family and friends. Despite his preference for managing his condition independently, he knows that his loved ones are always there for him when needed. This support has been invaluable in helping him navigate the challenges of his condition.

"My family has been really supportive of me," Tyler said. "I try to pretend I don't have the condition because I don't really like to be treated differently. But they know if I ask for help, I probably actually need it."

Tyler's determination to maintain his independence is evident in his approach to managing his condition. "I don't let a lot of people help me," he says. "I try to manage on my own as much as possible, but it's comforting to know that my family is there for me if I need them."

Dr. Dubey also acknowledges the importance of a strong support system in managing chronic conditions. "Having a supportive network can make a significant difference in a patient's journey," he says. "It provides emotional and practical support, which is crucial for long-term management."

Tyler's support system extends beyond his immediate family. He has also received encouragement from friends and colleagues who have been understanding and accommodating of his condition. "My friends and co-workers have been great," Tyler said. "They understand what I'm going through and are always willing to lend a hand if I need it."

Future goals and dreams

Looking ahead, Tyler hopes to continue improving his fine motor skills. He remains optimistic about his progress and is grateful for the advancements in diagnostic laboratory testing that led to his correct diagnosis.

"We are hopeful that with continued treatment, Tyler will see more improvement,” Dr. Dubey adds. “The early signs are promising, and we aim to stop the progression of the disease and help him regain as much function as possible."

Tyler's goals extend beyond his physical health, as he also hopes to continue excelling in his career and pursuing his hobbies. "I want to keep working and doing what I love," he says. "Having a clear understanding of my health and a treatment plan that works gives me hope for the future."

Tyler also hopes to inspire others who may be facing similar challenges. "If my story can help someone else get the right diagnosis and treatment sooner, then it's worth sharing," he says. "I want others to know that there is hope and that they are not alone."

In addition to his personal goals, Tyler is also passionate about raising awareness for NF155-IgG4 autoimmune nodopathy.

"I want to help others understand this condition and the importance of early diagnosis," he says. "The more people know about it, the better chance they have of getting the right treatment."

Tyler's story is a testament to the importance of early and accurate diagnostic testing in managing complex medical conditions, and his journey further highlights the advancements in diagnostics testing and medical expertise available to patients at Mayo Clinic.

"Tyler's case underscores the importance of continued research and development in the field of neuroimmunology,” Dr. Dubey says. “The ability to accurately diagnose and treat rare conditions like NF155-IgG4 AN can make a significant difference in patients' lives."