Menakuru, Sasmith R.Atta, MonaAmmannagari, NischalaYounes, Mohamad2024-02-132024-02-132023Menakuru SR, Atta M, Ammannagari N, Younes M. Hyperammonemic Encephalopathy: A Rare Presentation of Relapsed Multiple Myeloma. J Hematol. 2023;12(3):128-132. doi:10.14740/jh1097https://hdl.handle.net/1805/38413Hyperammonemia is a rare cause of encephalopathy in multiple myeloma in the absence of hepatic involvement. This is the only reported case of a 74-year-old man who presented with multiple myeloma and achieved complete remission but developed hyperammonemia afterward. He was aggressively treated with a combination of chemotherapy and immunotherapy, with a resolution of his encephalopathy; however, within one month, he relapsed with encephalopathy. He ultimately decided to pursue comfort-care measures. The authors conclude that hyperammonemia in multiple myeloma is a rare but important differential in patients with encephalopathy of unknown causes. Aggressive treatment is of the utmost importance due to the high mortality associated with the condition.en-USAttribution-NonCommercial 4.0 InternationalHyperammonemiaEncephalopathyMultiple myelomaTreatmentArticle