Unusual course of nemaline myopathy

A boy with onset features common for a moderate form of congenital nemaline myopathy, after some years developed scapulo-humeral syndrome. Extra- and intrafusal muscle fibers overloaded with rods and indicating focal degenerative changes were seen in the first biopsy. The biopsy was later repeated and revealed an improvement in muscle architecture with a dramatically decreased number of rods. This transformation suggests that rods, as well as Z-line streaming, might be a reversible anomaly of Z-discs.