Rimmed vacuoles

What it means

Presence of abnormal vacuoles (membrane-bound organelles) in the sarcolemma. On histological staining with hematoxylin and eosin, rimmed vacuoles are popcorn-like clear vacuoles with a densely blue rim. The vacuoles are often associated with cytoplasmic and occasionally intranuclear eosinophilic inclusions.

Rimmed vacuoles are characteristic for inclusion-bosy myositis, but are also seen an a number of other diseases. This term implies that rimmed vacuoles are found histologically. In some cases, the majority of muscle fibers are involved, but in others, rimmed vacuoles can be found in only a minority of fibers.

Rare diseases that can present with this22

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, and Orphanet separately records 2 diseases where this sign is specifically absent. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Rimmed vacuoles on biopsy