A New York Times diagnosis column by Lisa Sanders MD described a 27 year old man with exercise intolerance and sensory loss. The patient had several hospital Emergency Department visits after which the doctors would “pronounce him just fine”.
It all started a couple of months ago, when he noticed that his hands and fingers felt numb. Then he started having chest pains — a strange tightness that made it hard for him to breathe… He was a garbage collector and noticed that the short sprints from house to truck, which had been part of his daily routine, now left him panting. And the cans he emptied felt heavier. His muscles hurt constantly; he had frequent cramps… There were other symptoms too: he was losing weight — 20 pounds in two months. And he was tired. After work, he’d nap, get up for supper, then go back to bed. He also had terrible constipation…
On one of these Emergency Department visits anemia was noted. Using this information in SimulConsult’s diagnostic decision support system one can get diagnostic suggestions, which focused on Vitamin B12 deficiency (subscribers can click here to run the software with this information):
At a subsequent Emergency Department visit some physical findings were noted:
On examination there was no evidence of muscle atrophy, and while he easily passed the standard doctor’s-office tests of strength, the resident thought that was because those tests were not designed for someone with greater-than-average strength, like this young man. The patient had decreased sensation in both his hands and feet — a so-called stocking-and-glove distribution. When the doctor tapped his joints with her small rubber hammer, there was no spontaneous jerk. No reflexes. When she asked the patient to close his eyes and tell her whether she had moved his great toe up or down, he couldn’t say.
Adding this information strengthened the case for B12 deficiency (click here to run this in the software):
The “Add tests” tab of the software recommends the tests that were done and confirmed the diagnosis:
The tests were not expensive and could have been done earlier if the doctors had spent a few minutes to consult software to help with diagnosis. On one of the earlier Emergency Department visits the patient had recounted “My fingers were too weak… I couldn’t hold on tight. Just one bump and I would have been on the ground.” The delay in diagnosis could have resulted in significant injury.
Note the red asterisk near the diagnosis. Clicking such asterisks provide non-obvious information about a disease, here that “Treating B12-deficient patients with folate alone may worsen associated neurologic damage”. Folate deficiency also causes anemia with large red blood cells, and a doctor could be tempted to give both B12 and folate to cover possible causes of the abnormalities found on the blood tests. The red asterisk makes clear that such a strategy could make the patient worse.