Laurence-Moon syndrome

Laurence-Moon syndrome (LMS) is an extremely rare autosomal recessive genetic disorder historically distinguished from Bardet-Biedl syndrome, though the two conditions share overlapping features and have been subject to considerable nosological debate. Laurence-Moon syndrome is characterized by the combination of retinitis pigmentosa (progressive degeneration of the retina leading to vision loss), spastic paraplegia (progressive stiffness and weakness of the lower limbs), intellectual disability, and hypogonadism (underdevelopment of the reproductive organs with reduced or absent production of sex hormones). Unlike Bardet-Biedl syndrome, classic Laurence-Moon syndrome typically does not include polydactyly (extra fingers or toes) or truncal obesity as primary features, though some clinical overlap exists. The condition affects multiple body systems, including the central nervous system, the eyes, and the endocrine and reproductive systems. Neurological involvement manifests as progressive spastic paraplegia, which can significantly impair mobility over time. The retinal dystrophy typically presents in childhood and may progress to severe visual impairment or blindness. Hypogonadism can lead to delayed or absent puberty and infertility. Intellectual disability ranges from mild to moderate in most reported cases. There is currently no cure for Laurence-Moon syndrome. Management is supportive and multidisciplinary, involving ophthalmologists for monitoring and managing vision loss, neurologists for spasticity management (including physical therapy and antispasticity medications), endocrinologists for hormone replacement therapy to address hypogonadism, and educational support services for intellectual disability. Genetic counseling is recommended for affected families. The molecular genetic basis of Laurence-Moon syndrome remains incompletely characterized, and some researchers consider it part of the broader Bardet-Biedl syndrome spectrum, with mutations in ciliopathy-related genes potentially implicated.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Common questions about Laurence-Moon syndrome