BACKGROUND: Silent and spontaneous colonic migration of a ventriculoperitoneal (VP) shunt is an extremely rare, life-threatening long-term complication, driven by chronic foreign-body erosion. It can precipitate severe retrograde central nervous system (CNS) infection insidiously, even in the complete absence of typical abdominal symptoms or peritonitis.

CASE REPORT: A 63-year-old man with a history of VP shunt placement presented 2.5 years after the procedure with fever, somnolence, and elevated inflammatory markers. Brain computed tomography (CT) and contrast-enhanced magnetic resonance imaging (MRI) revealed progressive hydrocephalus and prominent peri-catheter cerebral edema. Subsequent abdominal CT demonstrated spontaneous distal shunt catheter perforation into the colon, with retrospective imaging ruling out iatrogenic injury. Although cerebrospinal fluid and blood cultures were negative, a diagnosis of retrograde CNS infection secondary to colonic perforation was clinically established based on direct anatomical continuity and localized neuroimaging abnormalities. The patient successfully underwent emergency shunt externalization and removal, external ventricular drainage placement, and broad-spectrum antibiotic therapy covering enteric flora, resulting in complete resolution of neurological symptoms without long-term sequelae.

CONCLUSIONS: Transmural colonic migration of a VP shunt is a critical late-onset complication that can present solely as a retrograde CNS infection without abdominal manifestations or positive cultures. High clinical vigilance for occult intra-abdominal shunt displacement, correlated neuroimaging and abdominal imaging, prompt surgical intervention, and targeted antimicrobial therapy are essential to prevent severe infectious morbidity and optimize neurological recovery.

Keywords: Hydrocephalus, infections, Ventriculoperitoneal Shunt