Go With Your Gut Feeling

Serum heavy metal screening was performed. Unexpectedly, the level of arsenic was 5x upper limit of normal. This was confirmed on repeated testing 1 month later. Patient's partner was tested with normal results. Detailed questioning for possible sources of environmental, occupational, or recreational exposures that would put patient at risk of arsenic exposure were all unrevealing. Since serum arsenic is cleared within 24-48 hours of exposure, there was continuing exposure to arsenic. When asked whether he has any hobbies, patient thought and responded that he goes to his remote cottage weekly. When partner's normal testing was brought up, the patient said that he always goes to his cabin alone. When asked about the water source at the cottage, patient immediately recalled the water was well-sourced and not municipal. Reviewing his medical history, remote history of hemorrhagic colitis requiring colectomy was consistent with acute arsenic poisoning. When deed of purchase for the cottage was located, it was identified that hemorrhagic colitis occurred 3 months after the cottage was was bought 28 years ago. Pathology slides from the colectomy were retrieved and re-examined by several gastrointestinal pathologists who agreed that the samples were not consistent with previous diagnosis of Crohn's colitis. A research laboratory with the capability to perform Total Reflection X-ray Fluorescence (TXRF) was contacted and a sample of the colonic tissue excised 28 years ago was analyzed. Arsenic content of the colon was measured and was found to be 5.9 ppb, 3 to 10 times the mean arsenic concentrations found in visceral organs of normal subjects. Well water from the cottage is currently being tested. In retrospect, persistent mild leukopenia and thrombocytopenia were also consistent with arsenic toxicity. Thus, in this case, chronic exposure to arsenic for 28 years caused slowly progressive toxic optic neuropathy.