Skip to main content
. 2017 Mar 15;76(4):323–331. doi: 10.1093/jnen/nlx011

FIGURE 1.

FIGURE 1

Macrophagic myofasciitis morphology. (A–F) FFPE tissue. Low-power H&E stain shows perimysial and endomysial aggregates of macrophages with a lymphocytic component (A, asterisk). High-power H&E (B) and trichrome (C) stains on consecutive sections show macrophages percolating through the endomysial connective tissue without inducing apparent myofiber damage. The granular cytoplasm of the macrophages is highlighted by PAS with diastase (D), anti-CD68 (E) and Morin (F) stains on consecutive sections. (G–J) Frozen sections. The macrophages are intensely basophilic by H&E (G), strongly positive for acid phosphatase (H), but do not elicit alkaline phosphatase reactivity in connective tissue (I). Immunostain for MHC1 highlights the macrophages but shows minimal sarcolemmal upregulation in myofibers (J). (K, L) Electron microscopy shows macrophages containing spiculated electron dense inclusions characteristic of aluminum crystalloid.