Atypical Presentation of a Rare Disease: Eosinophilic Cholangitis Posing as a Cancer.

BACKGROUND A variety of benign etiologies of biliary stricture may initially be mistaken for hilar cholangiocarcinoma. Consequently, many patients undergo surgery for a benign disease that could have been treated medically. Eosinophilic cholangitis (EC) is an uncommon, benign, self-limiting disease that should be considered when approaching a case of obstructive jaundice since it causes biliary stricture formation. Transmural eosinophilic infiltration of the biliary tree is characteristic of EC. It may initially be indistinguishable from hilar cholangiocarcinoma. CASE REPORT We present a rare case of an 84-year-old male who was referred to our hospital for abdominal mass investigation with the provisional diagnosis of cholangiocarcinoma. During the workup, the index of suspicion for malignancy remained high as the typical laboratory and radiological findings for benign causes of biliary stricture were not present. Hence, the patient underwent left hepatectomy with caudate lobe resection and received a retrograde diagnosis of EC. CONCLUSIONS This case demonstrates that EC could present in the elderly with cardinal signs of cancer and absence of the typical findings of EC which was not previously reported. Since only 70% of patients present with peripheral eosinophilia, we stress on the importance of implementing diagnostic criteria for EC in the setting where peripheral eosinophilia is absent. Furthermore, this disorder has been reported to respond well to steroid therapy, hence, diagnostic criteria for EC would provide another treatment option for elderly and/or those who are not fit for surgery.