Damages of Cardiovascular System at Mucopolysaccharidosis Type I: Clinical Cases

Background. Cardiac involvement in patients with mucopolysaccharidosis (MPS) type I, or Hurler syndrome, has various phenotypes.Clinical Case Description. In the first case symptoms were indicative of acute severe heart failure which was confirmed by laboratory and instrumental diagnostic methods. Left heart chambers dilatation and left ventricular hypocontractility were revealed on echocardiography. Atypical disease course with no improvement on multicomponent therapy of heart failure let us to think about metabolic disease, so we confirmed it with tandem mass spectrometry and molecular genetic testing. Therefore this led to timely enzyme replacement therapy onset and allogeneic bone marrow transplantation that positively affect the disease outcome. The second case showed classic course of MPS I. Its clinical signs such as musculoskeletal and ENT-organ manifestations allowed us to diagnosis and later confirm it by tandem mass spectrometry and molecular genetic testing at the age of 3. The cardiac pathology presented by mitral valve leaflets thickening and 2nd degree regurgitation has been diagnosed later. In our view, early treatment onset should slow down the progression of heart damage.Conclusion. Several clinical variants of cardiac pathology at MPS I are presented. The need of constant cardiovascular system monitoring in children with MPS I is shown. It is also mentioned that cardiac pathology can be the first manifestation of the disease.