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The July 2003 Case of the Month (COM). A 62-year-old female patient experienced progressive muscular weakness over the last ten years, involving shoulder and pelvic girdle muscles, paraspinal and facial muscles. A biopsy was taken from the left deltoid muscle where hepatitis vaccination had taken place 4 weeks previously. The specimen revealed macrophagic myofasciitis due to the injection of aluminium-bound vaccines. The finding can be reproduced experimentally by injecting vaccines in rats. The pathomechanism is supposed to involve immune stimulation due to long term persistence of the adjuvant. Macrophagic myofasciitis has been suggested to occasionally cause myopathy but is supposed to be unrelated to the underlying myopathy in our patient.

Using light and electron microscopy, 65 cases of amyloid deposits in the heart were examined. Five different groups were distinguished: I. isolated atrial amyloidosis, II. senile cardiac amyloidosis, III. cardiac amyloid accompanying chronic infections and tumors, IV. cardiac amyloid accompanying plasma cell dyscrasia, V. idiopathic cardiac amyloidosis. Seen structurally, no principal differences in the precise localization of the amyloid deposits were found in any of the groups investigated. Amyloid is always deposited in the vicinity of cells with myocytic cell differentiation (i.e. the heart muscle cells, non-striated muscle cells of the vessels), whereby the relevant basement membranes serve as conductors. A systematic relationship between amyloid and the collagenous fibers of the interstitium or the tunica adventitia of the vessels could not be demonstrated, which shows the concept "pericollagen" to be inadequate for the morphological characterization of amyloid deposits in the heart. Whereas for group I a localized mechanism for the production of amyloid must be considered, in the case of groups II-V a vascular principle expression of a generalized amyloidosis seems to be the major factor. The question of the differing concentration of amyloid deposits in the heart suggests that localized factors (e.g. changes in the myocytic basement membranes) and quantitative changes of the amyloid-building proteins may also be important.