Melorheostosis with osteopoikilosis

Other Names: MSBD syndrome; Mixed sclerosing bone dystrophy

Melorheostosis with osteopoikilosis is a rare sclerosing bone dysplasia, combining the clinical and radiological features of melorheostosis and osteopoikilosis , that has been reported in some families with osteopoikilosis and that is characterized by a variable presentation of limb pain and deformities.

Epidemiology

Less than 5 families have been reported in the literature to date.

Cause

The combination of melorheostosis with osteopoikilosis may be an unusual complication of familial osteopoikilosis. Osteopoikilosis is caused by a germline mutation in the LEMD3 gene (12q14). A germline mutation in the LEMD3 gene may predispose individuals with osteopoikilosis to develop melorheostosis. However, the exact pathogenesis is currently unknown.

Inheritance

Autosomal dominant pattern, a 50/50 chance.

Osteopoikilosis is inherited autosomal dominantly. There are no reports of parent to child transmission of melorheostosis. Genetic counseling is possible.

Signs and symptoms

As osteopoikilosis is a benign, usually asymptomatic condition, the clinical signs are primarily those of melorheostosis that can manifest with joint contractures, pain, stiffness, limited joint functions, limb-length discrepancy and deformity.

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. 80%-99% of people have these symptoms

• Abnormal cortical bone morphology
• Complete duplication of the distal phalanges of the hand(Complete duplication of the outermost bones of the hand)
• Osteopoikilosis

5%-29% of people have these symptoms

• Hypertension
• Multiple lipomas(Multiple fatty lumps)
• Subcutaneous nodule(Firm lump under the skin)

NIH genetic and rare disease info

• NIH info on Melorheostosis with osteopoikilosis

Melorheostosis with osteopoikilosis is a rare disease.