Sinistropostion: A case report of true left-sided gallbladder in a Vietnamese patient.

•Left-sided gallbladder without situs viscerum inversus is a rare congenital anomaly.•Left-sided gallbladder is accompanied by anatomic variations: portal vein and/or biliary system anomalies, segment IV atrophy, variations in hepato-biliary vascular anatomy.•Left-sided gallbladder can present significant intraoperative challenges due to associated variations in ductal and vessel anatomy.•There are three proposed, embryologic mechanisms for Left-sided gallbladder without situs viscerum inversus.•Even the face of routine preoperative testing, ultrasound, and CT scan, left-sided gallbladder often remains undetected until surgery.•Laparoscopic antegrade cholecystectomy can be performed safely for left-sided gallbladder.