A rare syndromic mitochondrial disease in which the cause of the disease is a mutation in the COX4I2 gene. It is characterized by exocrine pancreatic insufficiency, dyserythropoietic anemia, and calvarial hyperostosis. The disease is MONDO_0012992 (pancreatic insufficiency-anemia-hyperostosis syndrome). Also known as: pancreatic insufficiency, dyserythropoietic anemia, calvarial hyperostosis syndrome.