Presacral abscess as a rare complication of sacral nerve stimulator implantation

Abstract

A 50-year-old man with intractable anal pain attributed to proctalgia fugax underwent insertion of a sacral nerve stimulator via the right S3 vertebral foramen for pain control with good symptomatic relief. Thirteen months later, he presented with signs of sepsis. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a large presacral abscess. MRI demonstrated increased enhancement along the pathway of the stimulator electrode, indicating that the abscess was caused by infection introduced at the time of sacral nerve stimulator placement.The patient was treated with broad spectrum antibiotics, and the sacral nerve stimulator and electrode were removed. Attempts were made to drain the abscess transrectally using minimally invasive techniques but these were unsuccessful and CT guided transperineal drainage was then performed. Despite this, the presacral abscess progressed, developing enlarging gas locules and extending to the pelvic brim to involve the aortic bifurcation, causing hydronephrosis and radiological signs of impending sacral osteomyelitis. MRI showed communication between the rectum and abscess resulting from transrectal drainage. In view of the progressive presacral sepsis, a laparotomy was performed with drainage of the abscess, closure of the upper rectum and formation of a defunctioning end sigmoid colostomy. Following this, the presacral infection resolved.Presacral abscess formation secondary to an infected sacral nerve stimulator electrode has not been reported previously. Our experience suggests that in a similar situation, the optimal management is to perform laparotomy with drainage of the presacral abscess together with simultaneous removal of the sacral nerve stimulator and electrode. Sacral nerve stimulation is the implantation of a permanent pulse generator that delivers controlled electrical impulses via an electrode placed in contact with the sacral nerve roots, the S3 nerve root being the most common. It is of proven value in the treatment of urinary and faecal incontinence, urinary non-obstructive retention, and chronic pelvic and anal pain including proctalgia fugax. 1 We report the case of a 50-year-old man having severe anal pain attributed to proctalgia fugax for 7 years. Treatments with caudal epidural injection and ganglion impar block had been unsuccessful. He was referred to a tertiary centre for chronic pain management, where a temporary trial of S3 nerve stimulation was successful in controlling his anal pain. A permanent nerve stimulator was then implanted with the electrode being sited adjacent to the right S3 nerve root with good symptomatic relief. The patient presented 13 months later with symptoms and signs of sepsis including poor appetite, weight loss, night sweats, pyrexia, leucocytosis and elevated C-reactive protein. Computed tomography (CT) showed a chronic presacral abscess and magnetic resonance imaging (MRI) demonstrated enhancement along the pathway of the implanted electrode, indicating that the presacral abscess was caused by infectio...

The clinical characteristics of patients with chronic idiopathic anal pain

“…The pain is usually severe, deep, and long-lasting, which constitute a significant constant threat to patients’ life quality [ 6 ]. Although new diagnostic techniques such as pudendal nerve terminal motor latency measurement, sacral nerve stimulation, botox injection, biofeedback and transanal ultrasound have been made available [ 1 , 7 – 9 ], the unknown etiology leads to poor diagnosis and treatment outcomes in patients with chronic anal pain and generally causes psychological disorders such as emotional disorders, depression and anxiety [ 4 , 10 – 13 ]. Therefore, the study of psychological factors and clinic characteristics that are implicated in the incidence of chronic anal pain and associated treatment outcomes may be of assistance in clinical practice.…”

Treatment of the infected sacral nerve stimulator: A scoping review

“…Two articles discuss infections of the gluteal pocket, 5,8 four articles discuss infections of the lead tract 8,10,13,18 . One case report discusses sacral osteomyelitis due to SNS infection 9 and another case discusses the formation of presacral abscess 17 …”

“…However, it appears all reported cases pertaining to abscess formation secondary to infected SNS implant required explantation. 9,17 There is no consensus on the antibiotic choice, method of administration, dose, and duration of administration for patients undergoing antibiotic therapy for infected SNS. General advice has been published, and cephalosporins are the most used antibiotic for infected SNS, given Staphylococcus aureus is the most common cause.…”

“…There are no guidelines stipulating which patients should undergo a trial of conservative management versus immediate complete explant, and it seems current treatment is influenced by treating surgeon and local hospital guidelines. However, it appears all reported cases pertaining to abscess formation secondary to infected SNS implant required explantation 9,17 …”

“…2 The literature presents a population that will fail conservative management and require explantation of their infected SNS system. 9,10,17,19,25,30 There is currently no data identifying populations at higher risk of failing conservative management. It is not clear which patients should undergo immediate explantation of their device, although staged implantations are more likely to have infection that require explantation.…”