Selenium (Se) Deficiency After Orthotopic Heart Transplantation (OHT) (P12-056-19)

Abstract

ObjectivesSe and selenoproteins play critical metabolic roles, as in glutathione peroxidase (antioxidant defense) and iodo-thyronine deiodinase 2 (thyroid hormone production). Other Se-dependent pathways can promote apoptosis and decrease oncogene expression. Se deficiency (SeD) is rare in the US, given its abundance in food and soil. SeD is linked to tobacco use, excessive ETOH consumption, birth control pills, and inflammatory bowel disease. SeD can increase the risk of prostate cancer and Burkitt’s lymphoma. Severe SeD can cause skeletal muscle dysfunction and endemic cardiomyopathy (Keshan disease). We present herein a case of SeD 7 + years after heart transplantation, in whom prostate cancer and Burkitt’s post transplant lymphoproliferative disorder (PTLD) developed. MethodsA 77-year-old male with hypertension, dyslipidemia, diabetes mellitus and non-ischemic cardiomyopathy underwent OHT in 2011. He developed prostate cancer in 2015, treated with hormonal and radiation therapy. In January, 2019 he had progressive dyspnea, muscle weakness, abdominal pain, weight loss and diarrhea x 1 week. An ascending colonic mass revealed Burkitt’s PTLD. A metabolic evaluation uncovered a serum Se of 31 mcg/L (normal range 63–160).The patient received TPN with additional Se. He underwent chemotherapy and developed tumor lysis syndrome, requiring renal replacement therapy. He remained on single drug immunosuppression with Tacrolimus. Renal function and oral intake returned after 3 weeks. ResultsOur patient presented with a severe SeD without apparent predisposing factors. He has developed 2 SeD-related neoplasms: prostate cancer and Burkitt’s PTLD. The congruence of his clinical course and biochemical results support the diagnosis of a true SeD. However, the etiology of the SeD state remains unknown. We hypothesize that his immunosuppression therapy with Tacrolimus may have played a role. If so, it could be a previously unidentified drug effect. ConclusionsSerum Se monitoring should be considered in post OHT patients who develop prostate cancer or Burkitt’s PTLD. Given the increased risk of prostate cancer in OHT patients, routine screening of Se levels and Se supplementation of deficiency states should be considered after OHT. Funding Sourcesnone.