Hall-Riggs Mental Retardation Syndrome

Clinical Features

Hall and Riggs (1975) reported a family in which 6 of 15 offspring of first-cousin unaffected parents had a characteristic syndrome consisting of severe mental retardation, microcephaly, depressed nasal bridge with anteverted nostrils, large lips, and progressive abnormalities of the bony skeleton. They had unexplained episodes of vomiting in infancy. None of the 6 developed speech even as adults. Scoliosis, flat femoral heads and short femoral necks, relatively short proximal segments of the arms, retarded growth, and flat epiphyses in the fingers and at the ankle were skeletal features. Cataracts, corneal clouding, visceromegaly, joint contractures, and lumbar gibbus were notable for their absence.

Silengo and Rigardetto (2000) reported a second family with Hall-Riggs syndrome. The male and female sibs presented with short stature, microcephaly, hypertelorism, a flat nasal bridge, large nose with a large tip and anteverted nostrils, a wide mouth with thick lips, and severe mental retardation. Radiographs showed mild spondylometaphyseal dysplasia with some epiphyseal involvement. Both children also had cysts in the septum pellucidum and a cavum vergae on MRI scan, and abnormal EEGs.