@article{oai:tsukuba.repo.nii.ac.jp:00045127,
 author = {Shoda, Junichi and 正田, 純一},
 issue = {2},
 journal = {胆道, Journal of Japan Biliary Association},
 month = {},
 note = {石症は胆囊や胆管の胆道系に結石が形成される疾患の総称であり，日常臨床において遭遇する頻度の高い疾患である．胆石症の自然史は，無治療にて追跡調査をしていくと，追跡調査前の 1 年間に胆道疝痛を経験した有症状患者では，調査前に胆道疝痛を経験しなかった無症状患者に比較して，より高頻度に症状が出現する．しかし，大多数の有症状患者において胆道疝痛は長期間にわたり持続することはなく，穏やかな自然経過をとることが多いとされる．無症状胆石の自然史において，重症合併症の発生頻度は数％である．重症合併症の中で最も頻度の高いものは急性胆囊炎である．無症状胆石の有症状化率は診断されてからの 1～3 年が最も高く，経過観察期間が長期にわたるほど合併症の発生頻度は低下してくる．観察期間中に胆囊癌の発生を認めた症例はなかったと報告されている．
無症状胆石の対応手順は原則的に経過観察することが推奨されている．

A gallstone is defined as a concrement present  in the biliary tract consisting f the gallbladder and bile duct. Gallstone diseases are often encountered in daily clinical practice. In the natural history of gallstones, a follow-up survey for gallstone patients with no treatment showed that the probability of having biliary tract pain during the prospective evaluation was significantly increased in the patients who had a prior history of biliary tract pain compared to those who had no history of pain before. However, the majority of symptomatic gallstone patients do not persist biliary colic for a long time but take a peaceful natural course. In the natural history of asymptomatic gallstones, the incidence rate of severe complications is reportedly a few percent. Among the severe complications, the most frequent one is acute cholecystitis. The conversion rate from asymptomatic to symptomatic gallstone is the highest with in a few years after the diagnosis is made, and the rate complications decreases in parallel to the observation period. Moreover, it has been reported that no occurrence of gallbladder cancer is found in the observation period. The corresponding manner for asymptomatic gallstone is generally advised to watch clinical course.},
 pages = {187--195},
 title = {胆石の自然史},
 volume = {31},
 year = {2017},
 yomi = {ショウダ, ジュンイチ}
}