Congenital myopathy associated with proximal extremity weaknesses, external
ophthalmoplegia, and eventual respiratory failure. In the neonatal subgroup,
severe hypotonia, delayed motor development, generalized muscle weakness and
amyotrophy which may progress or remain stable. This presentation corresponds
to a subgroup called “Central core disease" and susceptibility to malignant
hyperthermia has been suggested.
MmD; Multicore Myopathy with External Ophthalmoplegia;
Minicore Myopathy with External Ophthalmoplegia.
Remains unknown. No more than 30 cases of this
medical condition have been reported in the literature.
Autosomal recessive; also a possible dominant
Myopathy characterized by the presence of
multiple, short, core lesions (known as minicores) in most muscle fibers as a result
of sarcomere disorganization and mitochondria depletion. Four subgroups have
been identified. RYR1 mutations were recently identified in the moderate
form—the central core disease. The genes responsible for the three other
forms remain unknown, but a mutation of the selenoprotein N gene is
The most prevalent phenotype is characterized by
the predominance of axial muscle weakness that leads, in two thirds of
patients, to development of severe life-threatening respiratory
insufficiency and scoliosis. The second group is the classic form with
ophthalmoplegia, which occurs in only 10% of cases. The third group
consists of the mild cases of central core disease. The fourth group is rare
and probably consists of rigid spine dystrophy.
Assessment of severity of
respiratory failure and degree of cardiac involvement is necessary, with
complete pulmonary function test, blood gas analysis, and echocardiography.
High complication rate because of muscle weakness, respiratory insufficiency,
and cardiac myopathy (late onset). A risk for malignant hyperthermia has been
suggested in the subgroup (e.g., central core disease) of the disease but
remains unknown in the classic form. Positioning may be challenging because of
often severe spinal deformity.
Succinylcholine should be considered
absolutely contraindicated. Muscle relaxants are usually not mandatory and
must be carefully adjusted if used. Volatile halogenated agents are not
advisable because of the possibility of malignant hyperthermia.
Central core disease of muscle,
rigid spine muscular dystrophy. Association with short-chain acyl-CoA
dehydrogenase deficiency has been described.
Docquer MA, Veyckemans F, Prudhomme S, et al: Anesthesia in a child
presenting a anhydrotic ectodermic dysplasia associated with a multiminicore
myopathy. Can J Anaesth 47:449, 2000.
Ferreiro A, Quijano-Roy S, Pichereau C, et al: Mutations of the
selenoprotein N gene, which is implicated in rigid spine dystrophy, cause
the classical phenotype of multiminicore disease: Reassessing the nosology
of early-onset myopathies. Am J Hum Genet
Jungbluth H, Sewry C, Brown SC, et al: Minicore myopathy in children: A
clinical and histopathological study in 19 cases. Neuromuscul Disord