Heterogeneity of Nemaline Myopathy

Abstract

The marked heterogeneity of nemaline myopathy is again shown in the present series of 13 patients. Most children have a long-standing, mild, and slowly progressing proximal myopathy. Two brothers with extreme weakness died during the neonatal period of respiratory failure representing the X-linked variant. One adult with proximal weakness was also diagnosed as having nemaline myopathy. An unusual course was observed in 2 infants who initially had moderate weakness but subsequently developed severe generalized weakness including respiratory muscles. This led to irreversible respiratory failure requiring continuous ventilatory support for as long as 9 and 15 years, respectively. Although uncommon, the possibility of an imminent respiratory failure in initially weak infants should also be taken into account within the clinical spectrum of nemaline myopathy.

Unusual Fatty Infiltration of the Soleus Muscle in a Patient with Congenital Nemaline Myopathy: Fat-suppression Muscle MRI.

“…Thus, the size or distribution of type I fibers may contribute to vulnerability of the soleus muscle in several patients with congenital nemaline myopathy. Clinical courses of nemaline myopathy are varied (3). We compared the previous findings and our data of muscle MRI in congenital nemaline myopathy.…”

“…Congenital nemaline myopathy is characterized by muscle weakness and nemaline bodies in the muscle fiber (1)(2)(3)(4)(5). On the basis of neuromuscular symptoms and onset, this myopathy is generally classified as severe neonatal, moderate congenital and adult-onset forms (4,5).…”