Supine volume drop and diaphragmatic function in adults with Pompe disease: Table 1–

Abstract

To the Editors: 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]. The prominent diaphragmatic dysfunction in Pompe disease, together with the recent introduction of enzyme replacement therapy in adults, indicate a need for clarifying respiratory outcomes in adult-onset Pompe disease [2]. An international database of medical information on patients with Pompe disease has been set up by Genzyme Corporation (Cambridge, MA, USA), a manufacturer of replacement enzymes (www.pomperegistry.com). The only parameter recommended in the Genzyme Pompe registry for assessing diaphragmatic function is vital capacity (VC) in the upright position. However, it has been demonstrated in a population of patients with suspected diaphragmatic weakness that the supine VC drop provided a good estimate of diaphragmatic dysfunction [3–5]. The aim of the current study was to determine the relationship between invasive diaphragmatic indices and noninvasive respiratory function variables in patients with adult-onset Pompe disease. We retrospectively retrieved data from the clinical files of patients with adult-onset Pompe disease at the respiratory laboratory of the Raymond Poincare Teaching Hospital (Garches, France) between 2002 and 2010 for diaphragmatic muscle evaluation. Our study was approved by the French Commission Nationale de l’Informatique et des Libertes in accordance with current French legislation. …