Endoscopic biliary stenting is used for the treatment of different obstructive biliary diseases, such as benign conditions like choledocholithiasis, biliary stricture, and severe cholangitis, and for the treatment of malignant obstructive jaundice^[6]. Biliary stents are either plastic or metallic. Plastic stents are used to temporarily relieve obstructions and to maintain bile flow^[7]. This procedure stabilizes the patient before a subsequent surgical intervention or endoscopic treatment. Definite stenting with metallic stents is recommended for elderly patients with severe comorbidities who are not good candidates for ERCP or surgical intervention^[7]. The outcome of biliary stenting is good drainage and a low complication rate, but with time, stent occlusion can occur, more often with plastic stents^[8]. Therefore, plastic biliary stents are recommended to be removed or exchanged within 3–6 months of deployment to avoid infectious complications^[7].

Forgotten biliary stents (FBS) are defined as plastic stents that remained in situ for more than 12 months^[9,10]. The quick relief of symptoms and the endoscopic nature of the procedure may contribute to the instances of FBS. Patient’s lack of awareness, noncompliance, inadequate counseling, and poor documentation may also play a role^[10]. A study found that the most common reason for FBS reported by patients was that they were not informed about the long-term management of the stent^[9]. Trainee doctors often forget to counsel patients about stent follow-up and removal, and this in turn leads to this problem^[11]. Biliary stents are frequently forgotten in elderly patients, as suggested by our case and other reported cases^[5,10]. This may be explained by the fact that elderly patients face physical impairment, increased morbidity, and dependency, which may prevent them from seeking medical care. In countries like Sudan, financial constraints and a lack of healthcare facilities may also play an important role.

FBS can be asymptomatic and discovered accidentally during routine examination as in the case of our patient and other reported cases^[5]. It can remain asymptomatic for a long period and then symptoms appear. Patients can present with abdominal pain, nausea and vomiting, fever, itching, and jaundice^[10,11].

FBS can cause many complications, mainly cholangitis associated with CBD stones, obstructive jaundice, internal stent migration, and pancreatitis^[5,9]. It can rarely cause stentolith “de novo formation of biliary stones around the stent”^[9]. FBS can also remain silent for years without any obvious complications^[12].

According to the literature, patients with FBS are either symptomatic with complications, symptomatic without complications, or asymptomatic with complications^[5,10-14]. Interestingly, our patient was asymptomatic and did not have any complications, and this was a unique presentation.

Symptoms and complications are mainly due to stent obstruction. In benign disease, there is a passage between the CBD and the stent, which allows bile flow if the stent is obstructed. This may explain the absence of symptoms and complications in our patient^[13].

Our patient exhibited clinical signs of mild jaundice during a routine follow-up visit. However, the laboratory findings, including serum bilirubin levels from the liver function tests, may not accurately reflect her clinical condition. This discrepancy can be attributed to the current challenges in the healthcare sector following the war and the subsequent collapse of the healthcare system in Sudan. With many government central hospitals unable to perform essential laboratory tests, patients are compelled to seek private laboratory facilities. This often results in substantial delays between clinical evaluation and laboratory testing, potentially leading to misalignments between clinical presentation and laboratory results.

Uncomplicated FBS is usually treated by ERCP with stent removal and re-stenting^[5,11]. In complicated cases, ERCP typically fails, necessitating surgical intervention. The initial step is often CBD exploration, followed by additional procedures as needed, such as cholecystectomy, choledochoduodenostomy, or hepaticojejunostomy^[10].

Forgotten biliary stents constitute a huge health burden, with many serious complications that can be avoided if patients follow the recommended guidelines. Several measures have been proposed to increase patient adherence and compliance. A randomized controlled trial examined the effectiveness of short message service (SMS) on stent removal/exchange and found that patients’ adherence increased to stent removal/exchange after receiving the SMS^[14].

There is also promising evidence regarding the effectiveness of biodegradable biliary stents. Although they are still in trial, they will serve as a valuable alternative to conventional stents in patients with poor compliance^[12].

In conclusion, this case underscores the importance of diligent follow-up and patient education to prevent complications associated with prolonged stent placement. While our patient did not experience adverse effects, regular monitoring and timely stent replacement are crucial in managing patients with biliary stents to avoid potential complications.