全身性アミロイドーシスにおける胃のアミロイド沈着について―特に生検診断のために

Gastric Amyloid Deposition in Generalized Amyloidosis: For diagnosis using biopsy

要旨　全身性アミロイドーシスの診断に有用な胃生検の部位，数およびその深さを決定するために，全身性アミロイドーシス4例(原発性アミロイドーシス1例，骨髄腫に合併したアミロイドーシス1例，家族性アミロイドーシス2例)を検索した．各症例の胃をすべてパラフィンブロックにして，切片を作製し，コンゴーレッド染色とその偏光による観察によってアミロイドの沈着を確認した．4例ともアミロイドの沈着は粘膜下組織に最も顕著で，次いで固有筋層，粘膜筋板，粘膜固有層，漿膜の順であった．粘膜筋板では，いずれの部位にも沈着があり，実際の生検診断に当たっては，胃粘膜筋板まで採取すれば一応その目的を達成することができる．粘膜固有層および粘膜筋板へのアミロイド沈着は胃体部と幽門部に多く，その程度も強い傾向にあり生検時に胃体部から幽門部にかけて，全周の粘膜を数か所採取すればほぼ適当であると考えられた．

　Recently, it has been emphasized that biopsy of gastric mucosa is useful for making a diagnosis of generalized amyloidosis. In order to determine the appropriate number, sites and mucosal depth in the biopsy of the stomach, four autopsy cases of generalized amyloidosis (one case of primary amyloidosis, one case of amyloidosis associated with multiple myeloma and two cases of familial amyloidosis) were examined. Numerous paraffin blocks were made of the entire part of the stomach and tissue sections were prepared from each of the blocks. Deposition of amyloid substance in tissue sections was identified by Congo red stain and additionally the stained specimens were observed by polarized light.

　The results were as follows; 1. The deposition was the most prominent in the tunica submucosa, and subsequently the tunica muscularis, lamina muscularis mucosae, tunica propria mucosae and tunica serosa, in that order. 2. The deposition in the lamina muscularis mucosae was observed in all sections of the entire part of the stomach. 3. The deposition in the tunica propria mucosae and lamina muscularis mucosae was more prominent at the body and pyloric region than others.

　Consequently for the diagnosis of generalized amyloidosis, it may be sufficient to obtain several mucosal biopsy specimens containing the lamina muscularis mucosae from different walls of the body and pyloric region of the stomach.