It’s one thing if your cup runneth over. It’s another if it obstructeth your organs. Last year, doctors treated a woman in her 30s who presented with occasional pain in her side and abdomen, and blood in her urine. When it wasn’t immediately clear what was behind her symptoms, they ordered a CT scan. Her medical history, which included a gastric sleeve operation and the removal of a kidney stone three years earlier, led them to wonder if she might be experiencing a kidney stone relapse. But