May Acute Appendicitis Complicate the Management of Pseudotumor Cerebri in Shunt-Dependent Patients? A Paediatric Case Report.

Introduction: Shunt-dependent secondary pseudotumor cerebri may remain clinically stable for many years; however, intra-abdominal sepsis such as perforated appendicitis can necessitate abrupt shunt removal, eliminating cerebrospinal fluid (CSF) diversion and precipitating sudden, vision-threatening intracranial pressure (ICP) elevation. Case Presentation: A 17-year-old girl with a long-standing ventriculoperitoneal shunt for a childhood arachnoid cyst initially developed papilledema that was successfully managed with the addition of a lumboperitoneal shunt. Nine months later, she presented with perforated appendicitis requiring emergent appendectomy and removal of both shunts because of the high risk of ascending shunt infection. Although visual acuity was initially preserved after surgery, rapidly progressive bilateral papilledema developed within days, accompanied by marked retinal nerve fibre layer thickening and enlarging visual field defects despite maximal acetazolamide therapy. As reinstitution of CSF diversion was not feasible, bilateral optic nerve sheath fenestration (ONSF) was performed as a vision-preserving intervention. Visual acuity, visual fields, and papilledema improved promptly and subsequently normalised. Conclusion: Perforated appendicitis in shunt-dependent patients may precipitate abrupt, vision-threatening ICP elevation following unavoidable shunt removal. Abdominal pain in patients with a history of CSF diversion should raise immediate suspicion for intra-abdominal sepsis. Early recognition of appendicitis may prevent perforation-related shunt complications, and timely ONSF is critical to avert permanent optic nerve damage when CSF diversion cannot be promptly restored.