TRANSRECTAL STENT PLACEMENT FOR THE DEBRIDEMENT OF A PRESACRAL PHLEGMON

Michelle Ganyo, MD, Robert Lawson, MD. Naval Medical Center San Diego

INTRODUCTION: A presacral phlegmon is a contained collection of infected fluid and inflammation within the bony pelvis, posterior to the rectum and anterior to the sacrum, that usually arises as a complication of surgery, malignancy, inflammatory bowel disease, ischemic colitis or perforated viscous. Symptoms include low-back pain, pelvic pain and fevers. Antibiotics and supportive therapy are the mainstay of treatment. However, if abscess develops, drainage is required usually by trans-gluteal percutaneous and/or surgical methods, both of which are associated with significant morbidity and mortality. Endoscopic ultrasound (EUS) -guided drainage of perirectal and presacral abscesses is a well described minimally-invasive approach that permits clear definition of anatomy, real-time access to the abscess and creation of an internalized fistula through placement of one or more transluminal stents. However, to date there is no published report describing endoscopic treatment of the more complicated, clinically challenging presacral phlegmon. Here we present a case of a symptomatic presacral phlegmon recalcitrant to medical management that was successfully treated with an endoscopically placed retrievable, transmural, lumen-apposing metal stent.

CASE REPORT: This is a case-report of a 21-year-old, post-partum female who presented with fevers and recurrent lower back pain radiating to her rectum and vagina. Her spontaneous vaginal delivery was notable for a second-degree laceration that was primarily repaired at the time of delivery 3 months prior to presentation. Her past medical history was otherwise unremarkable. Radiographic imaging revealed several perirectal and presacral abscesses that were considered too small for percutaneous drainage. IV antibiotics were started and the largest abscess was targeted for EUS-guided aspiration. Unfortunately, her pain became constant and progressed in severity. A follow-up MRI a week later revealed a 7-cm presacral phlegmon.

RESULTS: Colonoscopy revealed a luminal bulge in the rectum but was otherwise normal. To permit drainage and multiple sessions of endoscopic necrosectomy, a 15mm lumen-apposing metal stent (LAMS) was placed transrectally under EUS-guidance into the presacral phlegmon. Endoscopic debridement with forceps and copious irrigation was performed. Over the following 2 weeks the patient reported purulent rectal drainage and resolution of her fevers and pain. Repeat endoscopy revealed a normal rectum and no sign of the stent. A follow up MRI showed a 3-cm area of heterogenous tissue in the presacral area.

CONCLUSIONS: Although not previously described for management of a presacral phlegmon, LAMS appears to be a safe and effective, minimally-invasive treatment option.