Well: Think Like a Doctor: The Gymnast’s Big Belly Solved
On Thursday, we challenged Well readers to solve the mystery of the 15-year-old gymnast who suddenly developed a huge, distended belly and intractable constipation. More than 500 readers weighed in.
There were actually two diagnoses:
Abdominal phrenic dyssynergia (APD) and
Pelvic floor dysfunction (PFD)
No one got both answers. (Confession: I never said that there were two.)
Dr. Ann Clark, an OB-GYN in Louisville, Ky., figured that this was some kind of problem of the abdominal muscles and did a quick search on PubMed to come up with the diagnosis of abdominal phrenic dyssynergia. She was the first of three readers to make this diagnosis.
Dr. Carrie Richardson from Chicago was the first of five readers to correctly identify pelvic floor dysfunction. She is a second year resident at Northwestern. Congratulations to both doctors.
Abdominal phrenic dyssynergia and pelvic floor dysfunction are two of the many problems now known as functional gastrointestinal disorders. These are problems of how the G.I. system works rather than problems of the structures themselves. Testing will not identify any organic problem and yet, somehow, the system doesn’t work normally.
A dozen readers suggested that the patient had irritable bowel syndrome, a disorder characterized by abdominal pain, cramping and changes in bowel habits. That is the most widely known of these functional disorders, but there are many others.
Functional G.I. disorders are extremely common, affecting, by some counts, up to 25 percent of the population at some point in their lives. Up to 40 percent of the G.I. problems seen by doctors are a result of these complaints.
And they’ve had a rough road to acceptance within the medical community. They are finally achieving a certain degree of legitimacy — if not as true diseases, then at least as problems that deserve attention and treatment. However, they are so new that there’s not even agreement about what to call them.
Initially these functional disorders were named based on the presence of a symptom that persisted over 3 to 12 months. Using this approach, known as the Rome criteria, this young woman would meet the definition for functional bloating disorder and functional constipation disorder or functional defecation disorder.
However, since the Rome criteria were published, in 2006, there have been efforts to categorize these disorders based on a better understanding of which specific part of the G.I. tract seems to be causing the problem.
Many of these disorders center on a loss of coordination between the involuntary parts of the G.I. tract, which run without our conscious direction, and the muscles that we can control. You can see how this works by looking at something like swallowing. We chew food and voluntarily start it on its way to the stomach, but about halfway down the esophagus, the involuntary part of the G.I. tract takes over and delivers the food to the stomach and destinations beyond.
That coordination usually works well, and we don’t pay much attention. But when it doesn’t, people choke or food can get stuck or even come back up. There are several functional disorders identified involving the loss of coordination in the systems controlling swallowing.
A Faulty Diaphragm and Pelvic Floor:
In this patient, it was the diaphragm, the dome-shaped muscle that divides the chest and abdomen and which we use to breathe, that caused the problem. Normally when the gut is full of food or gas, the diaphragm automatically relaxes upward, giving the abdomen more room. When that coordination is lost, the diaphragm contracts rather than relaxes when it senses abdominal fullness, and the gut is forced down and out rather than upward, where it would normally go. The abdominal wall muscles are forced to relax to accommodate this change, and that causes abdominal distention and bloating.
This condition is now called abdominal phrenic dyssynergia, the loss of synergy between the muscles of the abdomen (the diaphragm and abdominal wall muscles) and the phrenic nerve (the nerve that transmits sensation and movement to the diaphragm).
The young woman also had severe constipation. We choose when to go to the bathroom and have conscious control of the muscles that allow this to happen, a skill acquired very early in life. When this coordination is lost, the result is usually severe constipation.
Testing at one of the earlier hospitals showed that, like the diaphragm, the voluntary muscles of the pelvic floor were contracting rather than relaxing when there was a sense of fullness. Contraction of these muscles meant that nothing was getting through, hence severe constipation. This is now called pelvic floor dysfunction.
Why these disorders occur is not clear. Up to 25 percent of cases of irritable bowel syndrome follow a gastrointestinal infection. How and why that happens is still unknown. Links between others of these functional disorders and infection are still being investigated.
Fortunately, there is treatment available. Intensive physical therapy, guided by biofeedback, has been shown to be effective for both of these problems.
How the Diagnosis Was Made:
Given all the testing that the patient had had, Dr. Grothe, the doctor who saw her at the Mayo Clinic, was leaning toward functional bowel disease — as opposed to organic disease — early on in her thinking.
Initially she considered aerophagia, in which the habit of swallowing air causes bloating and discomfort. Typically, with this condition, symptoms are minimal in the morning and increase throughout the day as the patient swallows more air. But that was not the pattern this patient reported. Moreover, on exam, the young woman’s abdomen didn’t sound tympanic, as it would if it were full of air.
Dr. Grothe was also struck by the mother’s report that the young woman’s abdomen flattened out when she was under anesthesia. That suggested that the problem involved the muscles. So Dr. Grothe considered functional disorders of the muscles that would cause bloating and constipation.
Right away she focused on a newly described entity: abdominal phrenic dyssynergia. In studies, M.R.I.’s of patients with bloating were compared to those without. These images clearly showed downward displacement of the diaphragm when the abdomen was full, causing the distension and bloating. Since there is some conscious control of both the diaphragm and the abdominal walls, physical therapy can be useful.
This problem is frequently seen in conjunction with constipation caused by pelvic floor dysfunction, in which the muscles of the pelvic floor, like those of the diaphragm, constrict rather than relax when signaled by a sense of fullness. Could the abnormal positioning of the gut caused by the bloating lead to constipation by interrupting the normal coordination between the G.I. tract and the external muscles that facilitate going to the bathroom? It made sense.
Dr. Grothe explained her thinking to the family, then sent the patient to a special laboratory where this type of muscle coordination can be tested. If this was what she had, the treatment was intensive physical therapy using biofeedback to help the patient relearn what her body taught itself when she was an infant — how to coordinate the muscles that can be controlled with the involuntary muscles of the G.I. tract.
The test was positive, and the young woman began treatment with biofeedback — three one-hour sessions every day. On the weekend, she took the biofeedback equipment to the hotel where she and her family were staying and continued the three-times-a-day regimen. Within two weeks, the young woman’s stomach had shrunk nearly to normal. And within three, the constipation was gone completely.
Back to the Patient:
That was three months ago. The patient continues her three-times-a-day physical therapy routine at home. And she’s in the gym daily but she isn’t certain she will ever be able to compete in gymnastics at the same level again. Missing a week of practice will set you back, her mother, a gymnastics coach, told me. Missing a year can put you out of the game.
Still, the patient is working even harder than she did before she got sick to try to get back what she lost. And she’s hopeful.
“I’ll be back at the nationals and maybe — someday — the Olympics,” she said. “And if I’m not the one on the mat, I still hope to be there, coaching the one who is.”