Mucolipidosis III alpha/beta (MLIII alpha/beta) is a lysosomal disorder characterized by progressive slowing of the growth rate from early childhood, stiffness and pain in joints, gradual coarsening of facial features, moderate developmental delay and mild intellectual disability in most patients. The disease is mucolipidosis type III, alpha/beta (Monarch Disease Ontology identifier MONDO_0018931). Also known as: ML 3 alpha/beta, ML III alpha/beta, MLIII, Pseudo Hurler Polydystrophy, mucolipidosis type 3 alpha/beta, mucolipidosis type III, pseudo-Hurler polydystrophy.