Three weeks later when she returned to her doctor, the patient still had not received the test. And now she had a new problem: her mouth felt weak. It was difficult to talk; Her voice was different. At the end of a short conversation, their words were reduced to whispers. She couldn’t smile and she couldn’t swallow. Sometimes when she drank water it came from her nose rather than her throat. It was strange. And scary.
Chen wasn’t there so she saw a colleague, Dr. Abhirami Janani Raveendran, who was also an intern. Raveendran had never seen MG either, but knew it could affect the muscles of the mouth and throat. She asked the patient to have a blood test and sent Keung a message informing him of the patient’s troublesome new symptoms and the possible diagnosis.
When Keung saw the news, he was alarmed. He agreed that these symptoms made myasthenia gravis a likely diagnosis. And a dangerous one: patients with MG can lose strength in the muscles of the throat and diaphragm and become too tired to breathe. He called the patient. He noticed that her voice was nasal and thin – signs of muscle weakness. She said she had no difficulty breathing, but Keung knew that could change. So he told her to go to the hospital immediately. He frightened her. He wanted it.
A series of minor shocks
After receiving Keung’s urgent call, the patient drove her to the emergency room at Yale New Haven Hospital and was placed in the kneeling unit. This is the section for patients who are not sick enough to need the intensive care unit but may get to that point shortly. A technician would come in every few hours to measure the strength of her breathing. If it got too low, she would have to go to intensive care and maybe land on a breathing apparatus.
Keung wasn’t sure if the patient had myasthenia. Her eyelid was always droopy, her vision always double. With MG, he would expect these symptoms to worsen after using the muscle and improve after resting. And MG usually affected the muscles closest to the body. He would expect her shoulders to be weak, not her hands. Despite his uncertainty, he decided to start treatment for MG. He didn’t want to risk her getting any weaker. She was given high-dose steroids and intravenous immunoglobulins to suppress the parts of the immune system that attack the connection between her nerves and muscles.
The next day, Keung did a test that showed if the patient had MG. In the repeated nerve stimulation test, a tiny electrode is placed over the muscle, in this case the abductor digiti minimi, the muscle that moves the little finger. A series of small (and uncomfortable) shocks are delivered in rapid succession, causing the muscle to contract. In someone with normal nerves and muscles, every identical shock results in identical muscle contraction. In this patient, however, the first shocks produced weak contractions, and then they became even weaker. This charge is characteristic of MG. The blood test that Chen asked her to do was done at the hospital. It was positive. She had myasthenia gravis.