scotti: jeanna marraffa looked at all the symptoms, looked at the medical charts, and said, "i think to test for colchicine." marraffa: it's not very common. i've probably only had 15 colchicine cases in my career. narrator: colchicine works in ways similar to chemotherapy. it stops the normal process of cell division, which is good if you have something like gout. if you don't, it can be a problem. it's potentially very toxic, so it's used in very low doses and usually monitored clinically if people are taking it. narrator: mary's blood sample was subjected to a process called liquid chromatography tandem-mass spectrometry. the first step is to separate whatever is not blood from the rest of the blood sample. once those compounds are separated, they can actually enter the mass spectrometer. narrator: all compounds have a specific chemical signature that, once isolated, produce distinctive waveforms in the mass spectrometer. this is done based on the chemical characteristics and the mass of the compound. narrator: in this case, the resulting waveform was measured against the waveform