Supine volume drop and diaphragmatic function in adults with Pompe disease.

The onset of the adult form of Pompe disease, also known as acid maltase deficiency or glycogen storage disease type II, is a slow progressive muscular disorder in which little correlation exists between respiratory function and locomotor function [1]. The greater degree of respiratory dysfunction, compared with mobility loss, is mainly ascribable to the predominant and progressive involvement of the diaphragm [1].