Laurence-Moon-Biedl syndrome: report of two cases.

The Laurence-Moon-Biedl syndrome is characterized by features of familial occurrence, retinitis pigmentosa, obesity, polydactyly, hypogenitalism and mental retardation. Recently, several reports have suggested renal abnormalities as an additional cardinal feature of the syndrome. We present two cases of this syndrome from two different families. The first case was an obese eight-year-old girl with poor vision and signs of mental retardation beginning at four months of age. An intravenous urogram showed dilatation of the minor calyces of both kidneys. Genital agenesis and typical retinitis pigmentosa on fundal examination all supported the diagnosis of Laurence-Moon-Biedl syndrome. The patient's father and grandmother also had symptoms of poor vision, mental retardation and obesity. The second case was an obese 14-year-old girl with blurred vision and severe mental retardation noticed at two to three months of age. Fundi showed typical retinitis pigmentosa. She also had genital agenesis but no significant family history.