First reported case of abdominal Nocardia pseudocyst in the setting of a ventriculoperitoneal shunt: a case report and review of literature.

INTRODUCTION: Ventriculoperitoneal shunt placement is a common neurosurgical procedure that is used to divert cerebrospinal fluid from the ventricular system to the peritoneal cavity to alleviate hydrocephalus. Ventriculoperitoneal shunts carry the risk of several complications, from mechanical shunt failure and infection to rarer complications such as abdominal pseudocysts. Skin flora has been found to be the cause of most ventriculoperitoneal shunt-related pseudocysts. In this case presentation, we describe what we believe to be the first reported case of Nocardia species-induced ventriculoperitoneal shunt-related abdominal pseudocyst. CASE REPORT: A 27-year-old white male with a past medical history of cerebral palsy, congenital seizures, and hydrocephalus treated with four separate ventriculoperitoneal shunts presented to the emergency department for abdominal pain and distension for several months. A computed tomography scan of the abdomen showed a 6.1 cm × 10.7 cm × 14 cm thinly encapsulated fluid collection containing the peritoneal ends of the ventriculoperitoneal shunts, which was indicative of an abdominal pseudocyst. Percutaneous aspiration of the pseudocyst fluid grew Nocardia paucivorans. The patient had no history of immunosuppression. The patient underwent externalization of All the shunts along with pseudocyst drainage. Antibiotic therapy was guided by the infectious disease team. Daily cerebrospinal fluid samples were sent until three consecutive cultures demonstrated no growth. The patient later underwent revision of the shunt systems with placement of the distal catheters into the pleural cavities. He was discharged on oral Bactrim and scheduled for a 4-week follow-up in the neurosurgery clinic and the infectious disease clinic. We conducted a systematic review that yielded a total of 27 articles. Our case represents the first case of a Nocardia-infected abdominal pseudocyst associated with a ventriculoperitoneal shunt that has been reported in literature. CONCLUSION: Abdominal pseudocysts are a rare complication of ventriculoperitoneal shunt placement and can be associated with an underlying shunt infection. We present the first reported case of a Nocardia-infected abdominal pseudocyst associated with a ventriculoperitoneal shunt. The patient was successfully treated with shunt revision and antibiotic treatment. This case raises awareness that, in rare cases, uncommon central nervous system pathogens can cause abdominal sequelae in the setting of a ventriculoperitoneal shunt.