Intrathecal Drug Delivery Device Infection
A major complication of Intrathecal Drug Delivery Device (IDDD) implantationis infection.
Morgalla et al., assessed IDD-related complications in 51 patients who had IDD systems implanted for the treatment of chronic pain or spasticity.
Twelve patients (23.5%) presented a total of 22 complications. The main type of complication was catheter-related (50%), followed by pump failure, infection, and inappropriate refilling 1).
Device-related and surgical wound infection occurred in 12 patients (3%), and nine were regarded as severe in the series of Taira et al., 2).
Risk Factors
Patients with extremely low muscle bulk, visceral pumps may be impractical or impossible, with increased risks of dehiscence and infection 3).
Periodic refills of intrathecal implanted pumps do not seem to be a risk factor for infection if standard sterile refill procedures are performed. In a study, it was clear that comorbid infections from other parts of the body do not present as a risk for device contamination 4).
Prevention
Follett et al., concluded from the available data that the most effective antiinfection measures consist of adherence to published guidelines and recommendations that apply to surgical site infections (SSIs) in general 5).
The use of vancomycin powder in patients with implants in the series of is series of Ghobrial et al., did not reduce infection rates compared to published historical controls, and was elevated compared to institutional controls 6).
The combination of local neomycin/polymyxin with systemic antibiotic therapy can lead to a significantly lower rate of postoperative infection than when systemic antibiotics are used alone 7).
The subfascial implantation technique was associated with a reduced rate of local wound and pump infections and provided optimal cosmetic results as compared with that observed in retrospective cases 8).
Treatment
The current standard of care in the treatment of IDDD infection necessitates that the pump be explanted and the infection treated prior to implantation of a new IDDD. This process leads to long hospital stays, interruptions in optimal medical management, and a high risk for dangerous drug withdrawals.
Infections can be treated with repetitive local application of gentamicin-impregnated collagen fleece 9).
Leibold et al., describe a technique that allows for the explantation of the infected pump and implantation of a new pump concurrently, which they have named the “Turner Switch” technique in honor of its inventor.
The authors conducted a retrospective analysis of cases of infected IDDDs in which patients underwent simultaneous explantation of the infected pump and implantation of a new pump. Demographics and clinical data were collected.
Data from a total of 17 patients (11 male, 6 female) who underwent simultaneous IDDD explantation and implantation to treat infections were analyzed from a 3-year period. No patients experienced infection of the newly implanted pump or catheter. Of the 17 patients, 14 (82.4%) had baclofen pumps to treat spasticity and 3 (17.6%) had fentanyl pumps to treat chronic pain. The median hospital stay was 7 days, with 16 of 17 (94.1%) patients able to be discharged home or to a facility with a level of care similar to their preoperative care. All patients ultimately experienced complete resolution of their initial infections. Five patients (29.4%) required a return to the operating room within the next 5 months (for repair of a CSF leak in 2 cases, for treatment of infection at the old pump site in 2 cases, and for treatment of a CSF leak compounded with infection in 1 case). No patient experienced infection of the newly implanted pump or catheter.
IDDD infections represent a large portion of morbidity associated with these devices. The current standard of care for deep pump infections requires pump explantation and a course of antibiotics prior to reimplantation of the IDDD. The authors demonstrate the effectiveness of a procedure involving simultaneous explantation of an infected pump and implantation of a new pump on the contralateral side in the treatment of IDDD infections 10).
Ingale et al., suggested that consideration should be given to selective dorsal rhizotomy (SDR) as an alternative in patients previously implanted with Intrathecal Drug Delivery systems complicated by infection or nearing end of battery life 11).
Case reports
A patient with pump-site infection and Escherichia coli meningitis secondary to transcolonic perforation of an intrathecal baclofen pump catheter. While this is rare, we review the intraoperative precautions and best practices that should be taken to prevent and manage this unusual complication 12).
Intrathecal drug delivery device infection with Mycobacterium fortuitum was not been reported previously. Aliabadi et al., reported a case of an implanted baclofen pump infection and associated mycobacterium meningitis due to Mycobacterium fortuitum. The entire pump system was removed and the patient was treated successfully with a prolonged regimen of antibiotics 13).
In a case neurological complaints were pain and dysaesthesiae in the lower back and thigh, as well as paresis of the ileopsoas muscle. MRI of the lumbar spine showed an intradural-extramedullary mass at the level of L1 homogeneously enhancing with gadolinium. This mass was situated at the tip of an intrathecal catheter implanted 11 years before for a morphine trial infusion as therapy for phantom pain after amputation of the right arm. Now, removal of the catheter was performed. Cultures of lumbar CSF and the catheter tip demonstrated coagulase negative staphylococcus. Antibiotic medication with cephalosporines was given for 6 weeks. After removal of the catheter, the patient was free of pain and he progressively regained full neurological function. Although most catheter-associated granulomas reported so far were sterile in nature, bacterial infection should still be considered even years after catheter placement 14).
A patient who experienced a prolonged course of intrathecal baclofen withdrawal syndrome after removal of an implantable baclofen pump for treatment of pump infection and meningitis. The current literature outlines management options for the acute management of this syndrome. In this report the authors discuss the long-term presentation of this syndrome and suggest a treatment strategy for management of the syndrome. A 37-year-old man who presented with a baclofen pump infection and meningitis experienced acute onset of intrathecal baclofen withdrawal syndrome 12 hours after the pump had been surgically removed. The patient’s symptoms evolved into a severe, treatment-refractory withdrawal syndrome lasting longer than 1 month. Oral baclofen replacement with adjunctive administration of parenteral gamma-aminobutyric acid agonists only served to stabilize the patient’s critical condition throughout his hospital course. Replacement of the baclofen pump and restoration of intrathecal delivery of the medication was necessary to trigger the patient’s dramatic recovery and complete reversal of the withdrawal syndrome within approximately 48 hours. These findings indicate that a more direct method of treating infected baclofen pumps than immediate surgical removal is necessary to prevent the onset of intrathecal baclofen withdrawal syndrome. Various options for preventing the onset of the syndrome while simultaneously treating the infection are discussed 15).