Late-Onset Melas with Midd: An Uncommon Age of Presentation

Abstract

Objective: Maternally inherited diabetes and deafness (MIDD) is a rare form of diabetes caused by a mutation in mitochondrial DNA, usually a point mutation at position 3243 in the leucine tRNA gene. This same mutation can cause a rare but severe syndrome called mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). Methods: We describe a case of MIDD with acute mitochondrial decompensation that progressed to MELAS. Results: A 63-year-old male with MIDD and a history of hypoglycemic seizures presented for evaluation of altered mental status with fever, tachycardia, hypotension, and somnolence. His history was also significant for deafness and cochlear implants. The physical exam results were consistent with mild, proximal muscle wasting. The initial workup was concerning for sepsis and a urinary tract infection. Laboratory evaluation revealed lactic acidosis with normal white cell count, liver enzymes, and ammonia level. After fluid resuscitation and 4 days of broad-spectrum...