Hypoxic ventilatory depression in a patient with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke‐like episodes

Abstract

We describe a case of a 21-year-old man with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) who presented with hypoxic ventilatory depression. He had chronic hypoventilation, which was not explained by weakness of respiratory muscles. His hypercapnic ventilatory response was not impaired. In contrast, hypoxic ventilatory depression was observed in the isocapnic progressive hypoxic response test. After exposure to hypoxic conditions, his respiratory frequency decreased and tidal volume was unchanged. The hypoxic ventilatory depression was partially blocked by pretreatment with aminophylline. In conclusion, we need to be careful with patients with MELAS who are hypoxaemic because a vicious circle of hypoxia and hypoventilation can occur.

Mitochondrial DNA m.13514G>A heteroplasmy is associated with depressive symptoms in the elderly

“…Magnetic resonance imaging findings from m.13514A>G mutation carriers confirmed a typical MELAS pattern: the presence of lesions predominantly affecting gray matter and some adjacent white matter involvement . MELAS has been associated with a number of secondary manifestations including depression …”

“…67 MELAS has been associated with a number of secondary manifestations including depression. [68][69][70][71] Low-level mtDNA heteroplasmy in humans is common and may originate in early development [72][73][74][75] or even in the germline 26,27 despite protective mechanisms to minimize the maternal transmission of mutated mtDNA. 76,77 Whether this early-life mutation load is the result of maternally transmitted mtDNA mutations 78 or is acquired during a critical period in childhood or early adult life 79 remains uncertain.…”

Clinical evolution of Kearns-Sayre syndrome with polyendocrinopathy and respiratory failure

“…Sleep apnoea of central origin has been documented in Leigh’s disease (19), where spongy degeneration of the medulla is often shown, as well as in other mitochondrial encephalomyopathies (18). A reduced ventilatory response to hypoxia, hypercapnia, or both, has been demonstrated in progressive external ophthalmoplegia (20), KSS (21) and mitochondrial encephalomyopathy with lactic acidosis and stroke‐like episodes (MELAS) (22). Proposed causes of reduced responsiveness include altered metabolic state, carotid body or ninth cranial nerve dysfunction, muscular weakness and brain stem pathology affecting respiratory centres (21).…”

Sleep Disorders Associated with Primary Mitochondrial Diseases

“…He also presented with hypoxic ventilatory depression and chronic hypoventilation of uncertain etiology. 19 Following experimental exposure to hypoxia, his respiratory rate decreased, but tidal volume did not change. Sleep PSG was not performed.…”

“…A B mitochondrial disease. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] All patients were diagnosed with a sleep disorder and/or had complaints of abnormal sleep, based on family report or self-report.…”