The Dwarf Pony

Mucopolysaccharidosis Type IVB

In mucopolysaccharidosis type IVB (MPS IVB, Morquio disease B, deficiency of beta-Galactosidase) predominantly the skeletal system is affected: Deformities of the spine, thorax and extremities result in disproportionate short stature with a final height of 130 - 150 cm. In general, the symptoms are milder than in MPS IVA. Instability of the cranio-cervical junction, that may lead to paraplegia, represents a severe complication. Further symptoms include corneal clouding and hearing impairment. Patients with MPS IVB often suffer also from cardiac involvement such as cardiomyopathy or valve insufficiency. The intelligence is normal.