Intentional ingestion of elemental mercury requiring multi-step decontamination and prophylactic appendectomy: a case report and treatment proposal

Abstract

Background: Ingestion of elemental mercury (Hg0) is considered non-toxic. After massive ingestion, local intestinal complications may develop: retention within appendix is quite frequent but treatment is debated. We describe a case of intentional ingestion of Hg0 requiring multi-step decontamination and prophylactic appendectomy. Case detail: A 19-year-old woman was admitted to ED for abdominal pain. History revealed ingestion of large amount of Hg0 as suicide attempt. To prevent absorption, facilitate elimination, and avoid complications a conservative approach was started. Due to inefficacy of initial maneuvers colonoscopy with irrigation/aspiration was performed, repeated whole bowel irrigation was continued and second colonoscopy was performed to clean residual metal. Abdominal plain films confirmed the presence of retained mercury within the appendix in asymptomatic patient. To reduce risk of appendicitis, potential perforation, and possibly systemic toxicity, a prophylactic laparoscopic appendectomy was performed at day 5 with removal of all retained mercury without peritoneal spillage. Highest mercury concentration was 22.7 mcg/L in serum (1-4.5 mcg/L) and 5.1 mcg/L in urine (0.1-5 mcg/L).

Conclusions: After ingestion, metal retention in appendix is quite frequent. Evidence about optimal treatment are different and based on case reports. A multi-step approach with multidisciplinary evaluation tailored to the patient is suggested.

Keywords: chelating agents; colonoscopy; metals; poison control centre.