Spontaneous retroperitoneal hemorrhage in Menkes disease: A rare case report

ATP7A-Regulated Enzyme Metalation and Trafficking in the Menkes Disease Puzzle

Copper is vital for numerous cellular functions affecting all tissues and organ systems in the body. The copper pump, ATP7A is critical for whole-body, cellular, and subcellular copper homeostasis, and dysfunction due to genetic defects results in Menkes disease. ATP7A dysfunction leads to copper deficiency in nervous tissue, liver, and blood but accumulation in other tissues. Site-specific cellular deficiencies of copper lead to loss of function of copper-dependent enzymes in all tissues, and the range of Menkes disease pathologies observed can now be explained in full by lack of specific copper enzymes. New pathways involving copper activated lysosomal and steroid sulfatases link patient symptoms usually related to other inborn errors of metabolism to Menkes disease. Additionally, new roles for lysyl oxidase in activation of molecules necessary for the innate immune system, and novel adapter molecules that play roles in ERGIC trafficking of brain receptors and other proteins, are emerging. We here summarize the current knowledge of the roles of copper enzyme function in Menkes disease, with a focus on ATP7A-mediated enzyme metalation in the secretory pathway. By establishing mechanistic relationships between copper-dependent cellular processes and Menkes disease symptoms in patients will not only increase understanding of copper biology but will also allow for the identification of an expanding range of copper-dependent enzymes and pathways. This will raise awareness of rare patient symptoms, and thus aid in early diagnosis of Menkes disease patients.

Fatal Exsanguination Following Rupture of an Iliac Artery Aneurysm in an Infant With Menkes Disease

Menkes disease (MD) usually presents in infancy with respiratory and neurological complications. Severe isolated vasculo-connective tissue involvement in infancy is rare, and hence the precise and timely diagnosis is difficult. We report a case of an 8-week-old male infant who succumbed to acute, severe exsanguination, and hemorrhagic shock secondary to a large retroperitoneal hematoma due to rupture of a right iliac artery aneurysm. Perimortem musculoskeletal findings raised suspicion of nonaccidental injury. However, postmortem review of facial traits raised the suspicion of MD. MD was subsequently confirmed on genetic testing. Child health clinicians must remain aware of MD as a rare cause of infant vasculopathy or atypical skeletal abnormalities.