SIT is quite rare, with prevalence of 1 in 10,000–20,000 people worldwide. People with it have essentially mirror image of the major internal organs in the chest and abdomen. It is an autosomal recessive congenital condition and those people can live completely normal lives without any issues. It can be discovered incidentally during imaging or even during surgery, nonetheless, it can affect certain medical or surgical procedures just because doctors must keep the organ placement in mind. A well-known associated congenital anomaly is primary ciliary dyskinesia leading to Kartagener syndrome (situs inversus with chronic respiratory tract infections). In addition, congenital heart defects, great vessels malformations, polysplenia, and ectopic papilla have been reported.

Our case report represents an elderly lady with SIT and obstructive CBD stones necessitating ERCP with modified positioning and technique. She was transferred to our hospital after failed intervention at another center. Only a limited number of successful ERCPs in patients with SIT have been reported in the literature. Each case contributes valuable insights into technical modifications and endoscopic orientation strategies necessary for safe and effective intervention. Our patient is the second case reported in Saudi Arabia, along with a few case reports and case series from USA and China published in the past 5 years.

We emphasize the technical challenges of ERCP in SIT patients and the importance of experienced endoscopists capable of navigating the instruments in the opposite orientation to avoid potential complications like post ERCP pancreatitis, bleeding, perforation, or infection. Currently, there is no established consensus on the standard positioning for SIT patients undergoing ERCP. Patients could lie prone, supine, left lateral, right lateral, or even modify their position during the procedure at the discretion of the endoscopist. The endoscopist may even opt to use double-wire technique or transpancreatic precut to rescue inadvertent pancreatic duct cannulation.

We also highlight the crucial role of pre intervention imaging to address any associated congenital anomalies that may hinder the procedure, and to precisely plan the technique beforehand, raising its success rate. Typically, MRCP is considered the best noninvasive imaging modality for evaluation of the biliary and pancreatic ducts. It provides high resolution, detailed images without the risks associated with contrast agents. It is especially valuable for identifying the cause and level of biliary obstruction, detecting choledocholithiasis, and evaluating strictures or malignancies. Compared with computed tomography and ultrasound, MRCP offers superior soft tissue contrast and ductal visualization, making it the preferred diagnostic step before ERCP, which is now reserved primarily for therapeutic interventions rather than diagnosis. With careful technique and preparation, ERCP can be safely performed in these patients.