He could barely walk and had to give up golf. What happened?

In the spring, the 69-year-old man most of all missed playing golf. How he loved the cool South Carolina morning, the feel of the club in his hands, the movement of his arms and body in a perfect arc. But even before he had to stop, he noticed a change. The feeling in his fingers slowly faded, then their strength faded. He quit the game after nearly scoring a friend; his club went straight out of his hands at the end of the blow. Missed by a few inches.

There was so much he couldn’t do. He couldn’t open jars, couldn’t turn the doorknob. His wife gave him a special tool so he could button his own shirts. He had to wear slippers. He couldn’t even cut his own meat. He had always been independent, and each new loss seemed devastating to him.

He told his doctor about it years before he had to quit the game. She became worried and sent him to a neurologist. The specialist diagnosed him with carpal tunnel syndrome. She explained that the nerve that carries sensation from his fingers to the brain was compressed as it passed through a bony passage in his wrist called the carpal tunnel. It was an overuse injury and rest and splints usually helped. Not this time. And it soon became clear that the matter was not only in his hands. His legs began to burn, and then they lost the ability to feel. Finally, he felt as if he were walking on wooden blocks. Then his legs began to feel weak.

When he got worse, he saw a whole line of specialists. More neurologists and rheumatologists, and since he had cancer 20 years ago and was treated with radiation to the neck and chest, he visited a couple of oncologists. Almost anyone could tell him what he had: peripheral neuropathy, loss of nerve function in his arms and legs, and more recently, his arms and legs. But why did he have it, where did it come from and how could it be stopped – these basic questions continued to elude them.

He had blood, urine, nerve tests. Six years later, he knew that there were dozens of terrible diseases that he did not have. It wasn’t diabetes, HIV, Lyme disease or hepatitis. His thyroid was disabled due to the radiation therapy he received for cancer, but he took thyroid hormone every day. His level has always been perfect. Vitamin levels were normal.

More recently, a rheumatologist tested him for every autoimmune disease he could think of, and when none of the tests came back, he tried a high-dose course of prednisone. If it’s his immune system that’s failing, then suppressing that system, which is what prednisolone does, might help. When that didn’t happen, the doctor told him he didn’t know what else he could do. What the patient needed at the moment was specialists at the academic medical center. They saw a wider range of diseases and kept up with the latest research. He suggested a group of rheumatologists at the Medical University of South Carolina in Charleston, a couple of hours south. The man immediately called them, but for months he could not make an appointment. By then, he and his wife would be in coastal New Jersey, where they would spend every summer with their adult children.

Instead, he turned to the health care system at the University of Pennsylvania in Philadelphia. It was only an hour from their beach house, and a few years ago he had a pacemaker put in there. Just one call landed him an appointment with a Pennsylvania neurologist the following week from his home in North Myrtle Beach, South Carolina.

After the patient signed up for a video visit, Dr. Mariam Saleb listened intently as he spoke of the things he could no longer do and his growing weakness and disability. He could barely walk and had lost almost 40 pounds over the past few years. He was only 69 years old, but he felt like an old man. Salib asked him to stand up and show her how he walks. He leaned forward and used his hands to push himself upright.

Even in the video, Saleb could see that the patient’s arms had become almost skeletal, as if the fat and muscle had simply melted away. His arms were also much thinner than she expected from his physique. His gait was clumsy, his feet were spread far beyond the width of his hips, which gave him the characteristics of a Frankenstein’s monster, and he could not raise his toes on his right foot, so it dragged when walking. She needed to undergo further testing. When could he come to her office? Soon he told her. They traveled north in six weeks.

When she finally saw the patient, Saleb noticed that the man was even thinner than he looked during the video visit. And he almost didn’t feel his legs. When she pricked him with the tip of the safety pin, he didn’t even blink until she was above her knees. His hands were almost as bad. And he was right – he was very weak. She tested the nerves in his arms and legs, sending tiny pulses of electricity into one nerve and measuring the strength of the signal and the time it took to get from one point to another. There was almost no signal from the lower leg to the feet, and there was only a trace from the palms to the forearms.

There are hundreds of possible causes of peripheral neuropathy. Diabetes is perhaps the most common. Alcohol abuse can do this. So maybe too little vitamin B12 or too much vitamin B6. Some medications can cause this type of neuropathy, as well as some toxins. Autoimmune diseases and hereditary diseases can also.

Most peripheral neuropathies primarily affect sensation. He had a so-called stocking-and-glove neuropathy: the one that starts in the legs, spreads up to the arms and continues. Most of the time, the legs and arms burn and sting, as if they were being stuck with pins and needles, and then slowly, usually over the years, the sensation dulls. But such a rapidly progressive and profound loss of sensation, combined with weakness, was a wake-up call. Salib wasn’t sure what he had, but she was sure he needed to see someone even more specialized and referred him to a clinic that specialized in neuromuscular diseases.

Dr. Margaret Means was the first physician to express confidence in the possibility of a diagnosis. After the exam, she said, “You really have a lot to worry about, but I know we’ll get to the bottom of it.” Then she disappeared. Ten minutes later, she returned with a tall man in a dressing gown, whom she introduced as Dr. White. Chafik Karam.

Karam asked a few questions and reviewed the notes the patient had brought. After a brief examination, he told the patient that they would send him to a lab for more blood work, but first they wanted to take a biopsy of the subcutaneous fat on his abdomen to look for a condition known as amyloidosis. In this disease, the liver produces abnormal proteins that form fibers that circulate throughout the body, invading organs and nerves, and even fat and skin. These fibers interfere with the normal functioning of the body simply by their presence. They are one of the causes of peripheral neuropathy.

Two weeks later, Karam called with the results. What he had, Karam explained, was very rare, with about 10,000 cases worldwide. It was a type of amyloidosis caused by a genetic abnormality he had inherited from one of his parents. And this anomaly was the cause of many of his medical problems. That’s why he needed a pacemaker – because the fibers were preventing his heart from regulating its rhythm. That’s why he lost weight. His digestive system had difficulty absorbing the nutrients he ate. And that’s why he had this debilitating neuropathy. The patient thought about his parents, who died many years ago. Both had many health problems, but he had no idea which of them might have had amyloidosis.

His children were in danger, Karam told him: there was a 50/50 chance that he had passed on the abnormal gene to them. None of his children had been tested yet, and the patient was worried about what they might find. However, there are new drugs that can slow this process down, although they cannot reverse the damage already done. The patient is currently on two of these drugs and the deterioration in his physical abilities has stopped. He can still walk, albeit slowly. And he resigned himself to the fact that he would never play golf again. It’s easy enough to watch these days.

Lisa Sanders, MD, is the journal’s contributor. Her latest book is Diagnosis: Solving the Most Baffling Medical Mysteries. If you have a solved case to share, please email Lisa.Sandersmdnyt@gmail.com here.