title: Reversible respiratory muscle weakness in hypothyroidism.
abstract: Physiological studies performed 1 week after initiation of thyroid replacement showed persistence of significant respiratory muscle weakness in a patient presenting with hypothyroidism and hypercapnia. Repeat studies 12 months later demonstrated return of respiratory muscle strength to normal. Earlier reports on respiratory failure in hypothyroidism had postulated a critical role for respiratory muscle weakness in the genesis of hypercapnia. Since hypercapnia was rapidly reversed despite the persistence of severe respiratory muscle weakness, this explanation may not be always correct. It appears than in our patient thyroid replacement had its primary effect on the respiratory control system.
mesh_terms: D000368:Aged; D006801:Humans; D006935:Hypercapnia / Q000209:etiology; D007037:Hypothyroidism / Q000150:complications / Q000503:physiopathology*; D008297:Male; D012129:Respiratory Function Tests; D012132:Respiratory Muscles / Q000503:physiopathology*