250. Retrospective Analysis Of Shunt-related Abdominal Pseudocyst Management

Authors: Joyce Koueik; Joyce Koueik, MD; Bermans Iskandar, MD; Sara Sayyahmeli (Madison, WI)

Introduction:

VP shunt-associated abdominal pseudocysts have traditionally been treated with externalization and antibiotic treatment before reinternalization into the peritoneum or other body cavity, with the assumption that even culture-negative pseudocysts may be infected.

Methods:

We conducted a retrospective review of patients who presented with VP shunt-related abdominal pseudocysts between 2004 and 2019.  

Results:

Forty-five shunted hydrocephalic patients with 50 abdominal pseudocysts were identified. All patients presented with abdominal pain, and 13 with fever. Diagnosis was made on abdominal CT and/or ultrasound. Pseudocyst fluid was obtained via ultrasound-guided aspiration or distal catheter externalization. CSF was obtained from all patients via shunt tap. 16 patients (36%) had negative CSF and pseudocyst cultures, and 29 patients (65%) had positive cultures. All infected pseudocysts were associated with shunt infections. In the 3 months preceding diagnosis, there were 15 shunt revisions (5 proximal, 10 distal) in the positive-culture group, compared to 3 shunt revisions and 2 bladder augmentations in the negative-culture group. In the positive culture group, all shunts were externalized or removed and treated with antibiotics before re-placing the shunt or seeking shunt independence. In the negative culture group, 7 were similarly treated with distal shunt externalization, antibiotics, and reinternalization, while 7 others were treated with distal catheter repositioning and/or abdominal lysis of adhesions, and 11 with conversion to a ventriculo-pleural or atrial shunt. There were no re-admissions for infection.

Conclusion:

In this study, while culture-positive pseudocysts were always associated with shunt infection, often postoperative, culture-negative pseudocysts are often associated with abdominal adhesions or recent abdominal surgery. While the former requires standard protocol shunt removal/antibiotics, the latter can be treated with catheter repositioning into a different body cavity or a different peritoneal space with/without lysis of adhesions. We recommend that treatment of pseudocysts be guided by culture results.