Macrophage involvement in mitral valve pathology in mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome).

Abstract

Maroteaux-Lamy syndrome (mucopolysaccharidosis type VI) is a rare lysosomal storage disorder in which the pathologic storage of glycosaminoglycans in various tissues can lead to severe symptoms, including cardiomyopathy. We report on a child with Maroteaux-Lamy syndrome whose cardiac condition deteriorated and eventually led to cardiac failure at the age of 7 years due to severe mitral regurgitation. She received a mitral valve replacement and tricuspid repair with successful outcome. Histologic examination of the mitral valve showed abundant "clear" cells in both the leaflets and chordae tendineae. In Hurler disease (MPS I), similar cells have been identified as activated valvular interstitial cells (VICs, a myofibroblast like cell type). Here we report that the "clear" cells are CD68 positive, a frequently used marker of macrophage lineage. The "clear" cells remained unstained with the more specific macrophage marker CD14 while persistent staining of other cells demonstrated macrophage infiltration. From these observations, we infer that macrophages are involved in mitral valve pathology in MPS VI.

• Authors: Marion Brands, Jorine Roelants, Ronald de Krijger, Ad Bogers, Arnold Reuser, Ans van der Ploeg, Wim Helbing
• Journal: American journal of medical genetics. Part A (Am J Med Genet A) Vol. 161A Issue 10 Pg. 2550-3 (Oct 2013) ISSN: 1552-4833 [Electronic] United States
• PMID: 23949968 (Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 Wiley Periodicals, Inc.

Topics

• Biopsy
• Child, Preschool
• Female
• Humans
• Macrophages (pathology)
• Magnetic Resonance Imaging
• Mitral Valve (pathology)
• Mucopolysaccharidosis VI (diagnosis, pathology, surgery)
• Treatment Outcome