LGMD Type 2D is a form of Limb Girdle Muscular Dystrophy, caused due to reduction or absence of the alpha sarcoglycan protein. Like other LGMDs, and especially like other sarcoglycopathies, LGMD2D is characterized by muscle weakness, especially of the proximal girdle muscles. In LGMD2D, the thigh muscles and muscles of the shoulder blades are the most severely affected. Patients in whom the disorder appears early on in life have a severe form of the disease, whereas those in whom the condition expresses itself later on in life usually have a much milder course of progression.
Diagnosis is similar to other muscular dystrophies, and includes muscle biopsies, evaluation of serum creatine kinase (CK) levels, and electromyography studies. Molecular genetic testing is also available. The ondition is only managed by supportive treatment.
Fendri et al. (2006) described an extended consanguineous family with two siblings diagnosed with LGMD2D. Both patients had the onset of the disease at 5-years of age and had become wheelchair-bound by the age of 18. At the time of presentation, they were 31 and 25-years old. Upon examination, the elder brother showed severe kyphoscoliosis, amyotrophy in all four limbs, moderate calves hypertrophy, and CK level of 89 IU/l, while the younger sister showed severe proximal predominant muscle weakness in all limbs, severe reduction of all four sarcoglycans upon immunostaining, and CK of 313 IU/l. Mutation screening confirmed homozygous mutations in the SGCA gene in both patients, confirming the diagnosis of LGMD2D. At the same time, a second degree cousin of these patients was diagnosed with LGMD Type 2C.