A world of difference: David Voeltz
At 71, David Voeltz is a happily married family man who appreciates putting in a hard day’s work and enjoys spending time in the woods. But for David, the ability to walk through nature with his children and grandchildren, and to climb in and out of the dump truck that is an integral part of his work as a truck driver, has not always been a given. Just two years ago, most of David’s muscular function was gone. He was dependent on a wheelchair to move more than several yards, and dependent on his family to help him dress, navigate stairs, climb into bed, and maneuver into his vehicle.
The profound improvement in David’s mobility is the result of familial support and abiding faith, along with a steadfast search for answers that culminated in David undergoing a newly developed Mayo Clinic Laboratories antibody test (Test ID: NMS1). The test confirmed the presence of a condition called necrotizing autoimmune myopathy (NAM), and its results led to successful treatment for the rare, life-threatening disease.
“Before, it was like, am I ready for a nursing home?” says David, who lives in southeastern Minnesota. “But you’ve got to keep pushing and Dr. (Teerin) Liewluck and Dr. (John) Mills, they gave me my life back. It’s amazing.”
At 56, David was diagnosed with a slowly progressive form of muscle disease thought to be muscular dystrophy. Because of that, he was accustomed to incremental muscle wasting and weakness. But his condition took a nosedive in the months before undergoing the antibody test that confirmed the diagnosis of NAM — a serious, immune-mediated myopathy that causes rapidly progressive muscle weakness.
David’s swift decline started in spring 2019. The previous fall, David had an emergency appendectomy. During the surgery, he experienced a cardiac event, and as part of his cardiac rehabilitation, his Mayo Clinic team prescribed statin therapy to lower his cholesterol. David thought little of the treatment. But unbeknownst to him, it was having a toxic effect on his system.
“Everyday things that you normally would take for granted to do, it just wasn’t there,” David says. “You go to the bathroom, and you couldn’t get off the stool and would have to have somebody help you. Getting into bed, I couldn’t sit down and swing my legs into bed because the weakness was so bad. I couldn’t shower myself. It left me so fast.”
Care and support from his wife, Christine, (left) and his daughter, Megan, (right) were crucial for David Voeltz during his journey to a diagnosis of necrotizing autoimmune myopathy.
When David began experiencing swallowing difficulty, his family feared the worst. “He was dying in front of our eyes, every day,” says David’s daughter, Megan Sprout. “We were to the point of deciding to sell the house and having to build a one-level home super-fast because he was declining so fast, and we didn’t have a choice. One day he looked at my mom and said, ‘You’ve got to put me in a nursing home.’”
While the family grappled with accommodating David’s alarming condition, they continued looking for an explanation. David’s Mayo Clinic neurology team, who had diagnosed him with muscular dystrophy in 2007, attributed the sudden worsening to a change in the disease progression.
“We knew deep down, that wasn’t it, so we just kept questioning,” Megan says. “Could there be something else?”
As the summer drew to a close and David’s family worried that he would choke or stop breathing, David’s wife, Christine, pressed for an appointment with Dr. Liewluck, a Mayo Clinic neuromuscular neurologist who the family hoped could offer a different opinion on David’s worsening condition.
“My mom called every day at 8 a.m. asking if there were any cancellations to see Dr. Liewluck. One day she called, and there was a cancellation,” Megan says.
That same day, Friday, Sept. 27, 2019, David’s family drove him to Rochester and wheeled him to his appointment with Dr. Liewluck. After reviewing David’s medical history and conducting a thorough neurological exam, Dr. Liewluck believed something other than muscular dystrophy was at work.
“What made me think of an alternate diagnosis was just within the past four months, the muscle weakness that had been slowly progressing changed and became more rapidly progressing,” Dr. Liewluck says. “That would be very unusual for muscular dystrophy.”
Instead, Dr. Liewluck considered David’s history with statins, which he had been taking since his appendectomy. David’s worsening condition tracked with his postsurgical statin use. He was placed on three different kinds of statins, all of which were discontinued because of intolerable side effects.
“It has been known for the past few years that statins, common cholesterol-lowering agents, can trigger NAM,” Dr. Liewluck says. “It was quite obvious to me because his weakness became more rapidly progressive each time he was put on a new statin.”
Although scientists discovered in 2010 statin use can trigger an autoimmune response that causes the body to produce antibodies against the HMGCR (3-hydroxy-3methylglutaryl-CoA reductase), an actual test to check for the presence of these antibodies hadn’t been validated for clinical use by Dr. Mills’ team in the Neuroimmunology Laboratory and offered at Mayo Clinic until 2018.
“A few months before I saw David, there was a report of patients with NAM that can present with a slowly progressing course mimicking muscular dystrophy. So putting the pieces together, I thought David could have this unusual presentation of NAM triggered by statins,” Dr. Liewluck says. “Luckily, he got the testing, and it was positive, so it made the diagnosis easy.”
The following week, David received his first round of immunomodulation infusion therapy to combat the effects of the problematic antibodies. Since beginning therapy, his infusions have tapered from five days a week to one day a week and are currently once every two weeks.
David’s testing journey didn’t end with his NAM diagnosis. Because Mayo Clinic Laboratories archives patient specimens, serum collected from David in 2007 was tested and identified as positive for NAM antibodies. This discovery prompted his team to look further back in time to 1997 to pinpoint when the symptoms first started. That year, David, then 49, was prescribed a statin to treat high cholesterol. He stopped the medication after a short time because of elevated liver enzymes and muscle weakness, which slowly worsened. At that time, it was not known that statins could trigger NAM.
For David and his family, receiving a NAM diagnosis and learning that he never had muscular dystrophy brought with it mixed emotions, including relief at having answers; gratitude to Dr. Liewluck for his astute insight and to the Mayo Clinic Labs team for developing the test; and excitement for a treatment. But there was also frustration around the functional losses David has suffered that will never be regained.
“All of those years we lost because they weren’t able to diagnose in 2007 causes anger and frustration because I could have had more back if we knew what it was back in the day,” David says. “But it was impossible to know.”
Because the clinical presentation of muscular dystrophy and the unusual chronic form of NAM are similar, and muscle biopsies for the conditions look much the same, confirming a chronic NAM without antibody testing is nearly impossible, Dr. Liewluck says.
“Ten years ago, we didn’t yet know that statin use triggers NAM,” Dr. Liewluck says. “And for him to have weakness for over a decade, that’s very rare for NAM. If I saw him back then, I would have come to the same conclusion.”
Although David won’t regain his full strength and continues to struggle with fatigue and weakness, the treatment he receives every two weeks makes a significant difference. Worries over the long-term effectiveness of his treatment are countered by faith, David says, explaining, “We trust in the Lord and science.”
David will likely require some form of therapy for the rest of his life to counteract the effects of NAM, but the benefit he receives following each infusion assures him that he’s on the right path. “What a difference one lab can make — one thing can change a life,” he says.