BCG膀胱内注入療法後にアナフィラクトイド紫斑を認めた1例

Abstract

83歳男。患者は両下肢紫斑, 肉眼的血尿を主訴に受診し, 右側壁に単発有茎性乳頭腫瘍を認めて経尿道的膀胱腫瘍切除術(TURBT)が施行された。しかし4ヵ月後, 三角部, 頸部に腫瘍の再発を認め, 再度TURBTが行われた。その後, BCG膀胱内注入療法週1回を6回施行するも, 2度再発しTURBTを施行, この間, 患者の希望によりUFT内服療法が開始された。4度目のTURBT後はBCG膀胱内注入療法が週1回始められ, 初回, 2回注入日には発熱を認めたのみであったが, 3回目の注入日の翌日, 発熱と軽度そう痒感を伴う両下肢の皮疹が自覚された。この皮疹は軽快せず, 皮膚生検, リンパ球幼若化試験行なったところ, BCG膀胱内注入療法を契機に発症したアナフィラクノイド紫斑と診断された。安静で保存的に経過観察を行った結果, 約2週間で紫斑は軽快し, 以後は腫瘍を含め再発は認められていない。尚, BCG膀胱内注入療法に伴う紫斑の報告は我が国では認められず, 海外でも1例認めたのみで, 副作用として極めて稀と考えられた。

We report a very rare side effect, anaphylactoid purpula, after intravesical administration of bacillus Calmette-Guerin (BCG). A 83-year-old man presented with purpura located on his bilateral lower legs. He had received transurethral resections four times for superficial bladder tumors. Intravesical therapy using BCG was performed. During the treatment course, asymptomatic purpura was suddenly seen in the lower legs after the third administration. Lymphocyte stimulation test was highly positive for BCG. He was diagnosed with anaphylactoid purpura caused by BCG. Conservative treatment was selected because there were no concomitant diseases in other organs. There have been no signs of recurrence of tumors or purpura during the one-year follow-up. However, physicians need to be cautious of anaphylactoid purpura which could lead to severe diseases, such as renal failure, gastrointestinal dysfunction and systematic arthritis.