Hypertrophied muscle fibers

What it means

The presence of an increased amount of muscle fibers with an increased diameter. This feature can be ascertained by microscopic examination of a muscle biopsy sample. Together with fiber size variation and atrophied muscle fibers, and hypertrophied muscle fibers are commonly found in myopathies.

Muscle hypertrophy can be assessed at the whole-muscle level (macroscopic methods) or the muscle fiber level (microscopic methods). This term refers to hypertrophy assessed at the microscopic level.

Rare diseases that can present with this2

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Muscle fiber hypertrophy · Muscle fibre hypertrophy