Pseudo-Wilsonian Crisis in a ATP7B Heterozygote

Copper is an essential nutrient involved in vital bodily functions such as the electron transport chain, protection from oxidative stress, neurotransmitter synthesis, among others(1). Absorption of copper requires an acidic gastric environment and occurs predominantly in the duodenum(2). Balance is regulated via biliary excretion, mediated by ATP7B (copper-transporting ATPase 2), a copper-exporting transmembrane protein that also facilitates the synthesis of ceruloplasmin, the major carrier of copper in the serum(1). Additional homeostatic controls are present in the intestines, via copper transporters Ctr1 and ATP7A (copper-transporting ATPase 1) (2). By virtue of these regulatory controls, copper toxicity is rare.