Prurigo nodularis as a sentinel dermatologic sign of cholangiocarcinoma: A case report

Prurigo nodularis (PN) is a chronic, intensely pruritic skin disorder characterized by hyperkeratotic nodules and significant morbidity. Although PN is known to be associated with various systemic diseases, including hepatic and biliary conditions, its link to cholangiocarcinoma remains undocumented.We present a case of PN associated with bile duct stenosis secondary to cholangiocarcinoma, highlighting an uncommon but clinically important presentation of the skin–liver axis. A 71-year-old male with a history of diabetes and hypertension presented with generalized pruritus, widespread nodular skin lesions, fatigue, and jaundice. Laboratory investigations revealed a cholestatic liver profile and eosinophilia. Imaging demonstrated common bile duct stenosis with biliary dilatation, and endoscopic retrograde cholangiopancreatography with brush cytology confirmed cholangiocarcinoma. Skin biopsy confirmed PN. The patient was started on dupilumab, a biologic targeting IL-4 and IL-13, resulting in mild improvement in pruritus and skin lesions. However, his liver function deteriorated rapidly, culminating in severe hepatic failure and death within 17 days of admission. This case underlines the potential for prurigo nodularis to be an early dermatologic indicator of serious underlying hepatobiliary malignancies. It further supports the emerging evidence of skin–liver cross-talk and shared inflammatory pathways involving Th2 cytokines and neuroimmune dysregulation. Clinicians should maintain a high index of suspicion for internal malignancies, particularly cholangiocarcinoma, when encountering atypical or refractory PN. Our findings advocate for an integrated, multidisciplinary approach in evaluating chronic pruritus and underscore the need for heightened awareness of PN’s role as a possible cutaneous manifestation of internal disease.