Neurosurgical Care of Spinal Epidural, Subdural, and Intramedullary Abscesses and Arachnoiditis

Bacterial and Viral Infectious Disease of the Spine

Spinal infections are a diverse group of diseases affecting different compartments of the spine with variable clinical and imaging presentations. Diagnosis of spinal infections is based on a combination of clinical features, laboratory markers, and imaging studies. Imaging plays a pivotal role in the diagnosis and management of spinal infections. The characteristic imaging manifestations of bacterial and viral infections in the spine are discussed with key teaching points emphasized.

Para-spinal abscess presenting with abdominal pain-a case report of 'red herring' symptoms

INTRODUCTION

Paraspinal abscesses are rare infections affecting the paraspinal muscles and soft tissues. An evolving abscess may pose a threat to the spinal cord via the compressive effect which can manifest as impaired motor or sensory function at the corresponding vertebral level. Paraspinal abscess is often a late diagnosis due to non-specific symptoms at presentation. This results in high morbidity and mortality.

CASE PRESENTATION

We describe the case of a 59-year-old female with a paraspinal abscess presenting with epigastric pain who was initially worked up for a suspected intra-abdominal pathology, however computerised tomography of the chest, abdomen, and pelvis (CTCAP) revealed no abnormality. Later, rising inflammatory markers, accompanied by worsening cervicalgia, prompted a CT of the head, neck and thorax which revealed a soft tissue abscess compressing the thecal sac at cervical levels 1 to 3 (C1-3). This was successfully managed with radiologically guided drainage and long-term intravenous antibiotics. Our patient made a full recovery and a repeat MRI demonstrated resolution of the abscess.

CONCLUSION

We demonstrate that spinal abscess can present with a misleading combination of symptoms and highlight the importance of considering rarer differentials in the face of an evolving clinical picture. Our case also demonstrates that once the correct diagnosis is reached, patients can make an excellent recovery from uncomplicated spinal abscesses.

Evaluation of cefuroxime concentration in the intrathecal and extrathecal compartments of the lumbar spine-an experimental study in pigs

BACKGROUND AND PURPOSE

Optimal antibiotic prophylaxis is crucial to prevent postoperative infection in spinal surgery. Sufficient time above the minimal inhibitory concentration (fT > MIC) for relevant bacteria in target tissues is required for cefuroxime. We assessed cefuroxime concentrations and fT > MIC of 4 μg·ml-1 for Staphylococcus aureus in the intrathecal (spinal cord and cerebrospinal fluid, CSF) and extrathecal (epidural space) compartments of the lumbar spine.

EXPERIMENTAL APPROACH

Eight female pigs were anaesthetized and laminectomized at L3-L4. Microdialysis catheters were placed for sampling in the spinal cord, CSF, and epidural space. A single dose of 1500 mg cefuroxime was administered intravenously over 10 min. Microdialysates and plasma were obtained continuously during 8 h. Cefuroxime concentrations were determined by ultra-high-performance liquid chromatography.

KEY RESULTS

Mean fT > MIC (4 μg·ml-1 ) was 58 min in the spinal cord, 0 min in the CSF, 115 min in the epidural space, and 123 min in plasma. Tissue penetration was 32% in the spinal cord, 7% in the CSF, and 63% in the epidural space.

CONCLUSION AND IMPLICATIONS

fT > MIC (4 μg·ml-1 ) and tissue penetration for cefuroxime were lower in the intrathecal compartments (spinal cord and CSF) than in the extrathecal compartment (epidural space) and plasma, suggesting a significant effect of the blood-brain barrier. In terms of fT > MIC, a single dose of 1500 mg cefuroxime seems inadequate to prevent intrathecal infections related to spinal surgery for bacteria presenting with a MIC target of 4 μg· ml-1 or above.

Complications of Fluoroscopically Guided Cervical Interlaminar Epidural Steroid Injections

PURPOSE OF REVIEW

Cervical interlaminar epidural steroid injection is a common intervention in the management of cervical radiculitis. Given the large number of injections done annually, it is important to assess the potential complications associated with this procedure.

RECENT FINDINGS

Based on current published studies, the overall complication rate varies. The vast majority are minor complications. However, this review also identified potentially catastrophic complications following cervical interlaminar epidural steroid injections. Based upon our review, cervical epidural steroid injection is considered a safe intervention. Nevertheless, catastrophic complications such as spinal cord injuries from needle placement, infections, and epidural hematoma can occur. It is prudent to take appropriate measures to minimize these complications.

Intradural Staphylococcus aureus Abscess of the Cauda Equina in an Otherwise Healthy Patient

Abscesses involving the spine are usually located in the epidural space. In rare circumstances, intradural spinal abscesses can occur, typically in the setting of tuberculosis or other predisposing systemic conditions. In this illustrated case report, we discuss the imaging and intraoperative findings of an otherwise healthy patient with an intradural abscess of the cauda equina caused by Staphylococcus aureus. Although rare, intradural spinal abscesses can occur in the absence of typical “red flags” for infection, and a bacterial abscess should be considered in the differential diagnosis of intradural spinal cystic enhancing lesions.

Pediatric spinal infections-a review of non-tuberculous infections

Pediatric spinal infection includes spinal epidural abscess, spondylodiscitis and intradural (extramedullary and intramedullary) spinal infections. However, these entities are extremely rare and no clear guidelines exist for their management. Pertinent literature was searched and a detailed narrative review of this topic is presented.

Spinal Implants Can Be Inserted in Patients With Deep Spine Infection: Results From a Large Cohort Study

STUDY DESIGN

A retrospective, cohort study of 84 patients with deep spine infection managed at a major tertiary hospital over 14 years with a minimum follow up of 2 years.

OBJECTIVE

To determine the role of instrumentation in spines with deep infection.

SUMMARY OF BACKGROUND DATA

It is often believed that implants should not be inserted in patients with deep spine infection because of the risk of persistent or recurrent infection. However, there are often concerns about spinal stability and a paucity of evidence to guide clinical practice in this field.

METHODS

We compared the mortality, reoperation, and reinfection rates in patients with spine infection treated with antibiotics alone, antibiotics with debridement, and antibiotics with debridement and instrumentation. Significant outcome predictors were determined using multivariable logistic regression model.

RESULTS

Forty-nine males and 35 females with a mean age was 62.0 years had spine infection affecting the lumbar spine predominantly. The most common form of infection was osteomyelitis and spondylodiscitis (69.4%). Staphylococcus aureus was the most common causative organism (61.2%).There was no difference in terms of reoperation or relapse for patients treated with antibiotics alone, antibiotics with debridement, or antibiotics with debridement and instrumentation. However, compared with antibiotics alone, the crude inhospital mortality was lower for patients treated with instrumentation (odds ratio, OR, 0.82; P = 0.01), and antibiotics with debridement (OR 0.80; P = 0.02).

CONCLUSION

Spinal instrumentation in an infected spine is safe and not associated with higher reoperation or relapse rates. Mortality is lower for patients treated with instrumentation.

LEVEL OF EVIDENCE

3.

Diagnosis of spinal epidural abscess: a case report and literature review

INTRODUCTION

Spinal epidural abscess (SEA) is a rare but serious cause of back pain in the critical care setting. It occurs most commonly in adults in their fifth and sixth decades of life. Risk factors include diabetes mellitus, alcoholism, AIDS or other immunocompromised states, cancer, intravenous drug use, trauma and spinal surgery. The clinical presentation can be non-specific but the classical triad includes back pain, fever and neurological deficits. Magnetic resonance imaging (MRI) with gadolinium is the diagnostic imaging modality of choice.

CASE PRESENTATION

Here we report a case of SEA in a 63-year-old man with type II diabetes who presented with severe low back pain. He was found to have SEA likely secondary to a hip joint injection. The diagnosis was delayed due an earlier non-gadolinium-enhanced MRI of the spine showing no epidural abscess.

DISCUSSION

This case stresses the need for the definitive diagnostic study, MRI with gadolinium, in patients whose SEA is high on the list of differential diagnoses.

Spinal infections in children: A review

Spinal infections are uncommon but significant causes of morbidity and hospitalization in the paediatric population. These infections encompass a broad range of conditions, from discitis to osteomyelitis and spinal epidural and intramedullary abscesses. Paediatric spinal infections can be caused by a range of bacterial, viral, fungal and parasitic agents. Ultrastructural differences of the vertebrae and associated structures result in distinct mechanisms of pathogenesis of spinal infections in children compared to adults. The non-specific nature of symptoms produced by them can cause considerable diagnostic delays. Magnetic Resonance (MR) imaging can facilitate early identification of the disease, and distinguish it from other spinal pathologies. The association of antimicrobial resistant bacterial strains from some of the cases appears worrisome; as is the increasing incidence of Kingella kingae infections causing spinal infections. Rest and immobilization are the general treatment, and prompt initiation of antimicrobial therapy is warranted to ensure optimal clinical outcome. Most patients generally have a good prognosis; however, early identification and prompt initiation of antimicrobial therapy is essential to achieve the best therapeutic response.

Relationship Between Percutaneous Procedures and Lumbar Infections Based on Data From The National Health Insurance Review & Assessment Service of Korea

STUDY DESIGN

A study from the National health insurance database.

OBJECTIVE

To investigate the relationship between percutaneous procedures or open surgeries and spinal infections using the 5-year large unit national dataset.

SUMMARY OF BACKGROUND DATA

There is no nation-based research data on the relationship between percutaneous procedures and spinal infections in Korea.

MATERIALS AND METHODS

This study used disease codes (ICD-10: International Classification of Disease) and operation fee codes (national medical insurance) registered in the National Health Insurance Review & Assessment Service for the 5 years from 2007 to 2011. Using the above disease codes, the number of each percutaneous procedure, open surgery, and the number of lumbar infections were investigated by the regional and national units, and the relationship between procedures or open surgeries and lumbar infection was compared statistically.

RESULTS

Lumbar infection showed a gradual growing annual trend, with a 3-fold increase in 2011 compared with 2007. Percutaneous procedures (nerve blocks) increased by approximately 2.6 times over 4 years. Kyphoplasty tended to decrease each year. Open surgeries (posterior fusion, discectomy, and laminectomy) were at a similar level each year. Lumbar infection and percutaneous procedures were positively correlated, and a negative correlation was observed between kyphoplasty and open surgeries. The incidence of lumbar infection was higher in large cities than provinces and increased 2-3 times in 2011 compared with 2007 in all regions.

CONCLUSIONS

There was no significant difference in the number of open surgeries for the 5-year study, but the number of percutaneous procedures (nerve blocks) increased each year, showing an approximate 4-fold increase in 4 years. Lumbar infection showed a positive correlation with percutaneous procedures, and kyphoplasty and open surgeries were negatively correlated. Therefore, as selective nerve block procedure is also considered an important factor affecting the growing trend of lumbar infections, unnecessary procedures should be avoided to reduce the absolute number of infections.

Pyogenic Intradural Abscess of Lumbar Spine: A Case Report

We report a case of spinal intradural abscess which shows serial changes on magnetic resonance imaging (MRI). Well-encapsulated, rim-enhancing lesion with mass effect was visualized at ventral side of lumbar spinal canal on 17 days after initial negative MRI, which was thought to be epidural abscess. It was revealed to be intradural in location on operation and successfully treated by drainage and antibiotics. Follow-up MRI showed resolution of abscess. Clinical significance and pathogenesis of this case was briefly discussed.

Central Nervous System Infections

Central nervous system (CNS) infections—i.e., infections involving the brain (cerebrum and cerebellum), spinal cord, optic nerves, and their covering membranes—are medical emergencies that are associated with substantial morbidity, mortality, or long-term sequelae that may have catastrophic implications for the quality of life of affected individuals. Acute CNS infections that warrant neurointensive care (ICU) admission fall broadly into three categories—meningitis, encephalitis, and abscesses—and generally result from blood-borne spread of the respective microorganisms. Other causes of CNS infections include head trauma resulting in fractures at the base of the skull or the cribriform plate that can lead to an opening between the CNS and the sinuses, mastoid, the middle ear, or the nasopharynx. Extrinsic contamination of the CNS can occur intraoperatively during neurosurgical procedures. Also, implanted medical devices or adjunct hardware (e.g., shunts, ventriculostomies, or external drainage tubes) and congenital malformations (e.g., spina bifida or sinus tracts) can become colonized and serve as sources or foci of infection. Viruses, such as rabies, herpes simplex virus, or polioviruses, can spread to the CNS via intraneural pathways resulting in encephalitis. If infection occurs at sites (e.g., middle ear or mastoid) contiguous with the CNS, infection may spread directly into the CNS causing brain abscesses; alternatively, the organism may reach the CNS indirectly via venous drainage or the sheaths of cranial and spinal nerves. Abscesses also may become localized in the subdural or epidural spaces. Meningitis results if bacteria spread directly from an abscess to the subarachnoid space. CNS abscesses may be a result of pyogenic meningitis or from septic emboli associated with endocarditis, lung abscess, or other serious purulent infections. Breaches of the blood–brain barrier (BBB) can result in CNS infections. Causes of such breaches include damage (e.g., microhemorrhage or necrosis of surrounding tissue) to the BBB; mechanical obstruction of microvessels by parasitized red blood cells, leukocytes, or platelets; overproduction of cytokines that degrade tight junction proteins; or microbe-specific interactions with the BBB that facilitate transcellular passage of the microorganism. The microorganisms that cause CNS infections include a wide range of bacteria, mycobacteria, yeasts, fungi, viruses, spirochaetes (e.g., neurosyphilis), and parasites (e.g., cerebral malaria and strongyloidiasis). The clinical picture of the various infections can be nonspecific or characterized by distinct, recognizable clinical syndromes. At some juncture, individuals with severe acute CNS infections require critical care management that warrants neuro-ICU admission. The implications for CNS infections are serious and complex and include the increased human and material resources necessary to manage very sick patients, the difficulties in triaging patients with vague or mild symptoms, and ascertaining the precise cause and degree of CNS involvement at the time of admission to the neuro-ICU. This chapter addresses a wide range of severe CNS infections that are better managed in the neuro-ICU. Topics covered include the medical epidemiology of the respective CNS infection; discussions of the relevant neuroanatomy and blood supply (essential for understanding the pathogenesis of CNS infections) and pathophysiology; symptoms and signs; diagnostic procedures, including essential neuroimaging studies; therapeutic options, including empirical therapy where indicated; and the perennial issue of the utility and effectiveness of steroid therapy for certain CNS infections. Finally, therapeutic options and alternatives are discussed, including the choices of antimicrobial agents best able to cross the BBB, supportive therapy, and prognosis.

Spondylodiscitis occurring after diagnostic lumbar puncture: a case report

Spondylodiscitis is a rare disease which is generally seen after long-term epidural catheterization. However, spondylidiscitis developing after diagnostic lumbar puncture is very rare. Early diagnosis has a crucial role in the management of the disease and inclines the morbidity rates. However, the diagnosis is often delayed due to the rarity and insidious onset of the disease usually presenting with low back pain which has a high frequency in the society. If it is diagnosed early before development of an abscess requiring surgery or neurological deficit, it responds to antimicrobial therapy quite well. We report 66-year-old male case of spondylodiscitis developing after diagnostic lumbar puncture. The patient was treated with antimicrobial therapy. After antimicrobial therapy, findings of spondylodiscitis were completely resolved and no recurrence was seen in the period of 9-month followup.

Spondylodiscitis: standards of current treatment

BACKGROUND

Spinal infections are an important clinical problem that often require aggressive medical therapy, and sometimes even surgery. Known risk factors are advanced age, diabetes mellitus, rheumatoid arthritis, immunosuppression, alcoholism, long-term steroid use, concomitant infections, poly-trauma, malignant tumor, and previous surgery or invasive procedures (discography, chemonucleolysis, and surgical procedures involving or adjacent to the intervertebral disc space). The most common level of involvement is at the lumbar spine, followed by the thoracic, cervical and sacral levels: lesions at the thoracic spine tend to lead more frequently to neurological symptoms.

OBJECTIVE

The aim of the current paper is to describe current evidence-based standards of therapy in the management of SD by emphasizing pharmacological therapy and principles and indications for bracing and surgery.

METHODS

A PubMed and Google Scholar search using various forms and combinations of the key words: spondylodiscitis, spine, infection, therapy, surgery, radiology, treatment. Reference citations from publications identified in the literature search were reviewed. Publications highlighted in this article were extracted based on relevancy to established, putative, and emerging diagnostic and therapeutic standards, either conservative (antibiotic therapy and bracing) or surgical.

FINDINGS

To date, conservative therapy, based on targeted antibiotic therapy plus bracing, represents the mainstay in the management of SD. Proper diagnosis and tailored therapy can improve clinical results and decrease the chance of failure. Surgery should be an option only for patients with complications of this disease, namely deformity, neural compression and neurological compromise. Current standards in the setting of SD are continuously evolving, as can be seen in the recent advances in the field of radiological diagnostics, and the use of growth factors and cell-therapy strategies to promote infection eradication and bone healing after surgery.

Laminotomy with continuous irrigation in patients with pyogenic spondylitis in thoracic and lumbar spine

OBJECTIVE

Pyogenic spondylitis often results in acute neurological deterioration requiring adequate surgical intervention and appropriate antibiotic treatment. The purpose of this study was to conduct an analysis of the clinical effect of continuous irrigation via laminotomy in a series of patients with pyogenic spondylitis in thoracic and lumbar spine.

METHODS

The authors conducted a retrospective investigation of 31 consecutive patients with pyogenic thoracic and lumbar spondylitis who underwent continuous irrigation through laminotomy from 2004 to 2008. The study included 22 men and 9 women, ranging in age from 38 to 78 years (mean 58.1 years). The average follow-up duration was 13.4 months (range, 8-34 months). We performed debridement and abscess removal after simple laminotomy, and then washed out epidural and disc space using a continuous irrigation system. Broad spectrum antibiotics were administered empirically and changed according to the subsequent culture result. Clinical outcomes were based on the low back outcome scale (LBOS), visual analogue scale (VAS) score, and Frankel grade at the last follow-up. Radiological assessment involved plain radiographs, including functional views.

RESULTS

Common predisposing factors included local injection for pain therapy, diabetes mellitus, chronic renal failure, and liver cirrhosis. Causative microorganisms were identified in 22 cases (70.9%) : Staphylococcus aureus and Streptococcus spp. were the main organisms. After surgery, LBOS, VAS score, and Frankel grade showed significant improvement in most patients. Spinal stability was maintained during the follow-up period, making secondary reconstructive surgery unnecessary for all patients, except one.

CONCLUSION

Simple laminotomy with continuous irrigation by insertion of a catheter into intervertebral disc space or epidural space was minimally invasive and effective in the treatment of pyogenic spondylitis. This procedure could be a beneficial treatment option in patients with thoracolumbar spondylitis combined with minimal or moderate destructive change of vertebrae.

Spinal epidural abscess: aetiology, predisponent factors and clinical outcomes in a 4-year prospective study

Spinal epidural abscess (SEA) is a rare, but serious, condition with multiple causes. We prospectively studied the aetiology, predisposing factors, and clinical outcomes of SEA in all patients with SEA treated in our hospital's neurosurgical service from 2004 to 2008. For each patient, we recorded the medical history, comorbidities, focus of infection, pathogen(s), and outcome. The 36 patients (19 women and 17 men) ranged in age from 34 to 80 years old (mean 57; median 56). The SEA was primary (i.e., due to haematogenous spread) in 16 patients (44%); it was secondary to elective spinal procedures, either injections or surgery, in 20 patients (56%). The duration of follow-up was 12-60 months (mean 36; median 37.5). The most common pathogen, Staphylococcus aureus, was found in 18 patients (50%). Patients with primary SEA had different underlying diseases and a wider range of pathogens than those with secondary SEA. Only five patients (14%) had no major comorbidity; 16 of the 20 patients with secondary SEA (44% of the overall group) had undergone spinal surgery before developing the SEA; the treatment of the SEA involved multiple surgical operations in all 16 of these patients, and spinal instrumentation in 5 (14%); 22 patients (61% of the overall group) recovered fully.

Post-traumatic osteomyelitis with spinal epidural abscess of cervical spine in a young man with no predisposing factor

Spinal osteomyelitis with epidural abscess is a rare disease. Most patients have 1 or more predisposing factors, such as impaired immune system secondary to diabetes mellitus, chemotherapy for cancer, immunological compromised disease, and chronic renal or hepatic impairment. We present a case of a physically steady young man without any predisposing risk factor who suffered from cervical osteomyelitis with epidural abscess after neck blunt injury. This patient recovered well after one-stage anterior surgical debridement with implant instrumentation and proper antibiotics treatment. The initial accurate diagnosis rate of spinal epidural abscess is low, even in patients with predisposing factor(s). We present this case to raise the attention of medical staff to this disease in patients with or without any predisposing factor(s) in order to establish early diagnosis and treatment. Our case report also indicates that with adequate debridement and antibiotic coverage, one-stage surgery is a safe and efficacious method to treat patients with cervical spinal epidural abscess.

Magnetic resonance imaging features of spinal epidural empyema in five dogs

Spinal epidural empyema is defined an accumulation of purulent material in the epidural space of the vertebral canal. Spinal epidural empyema should be considered as a differential diagnosis in dogs with pyrexia, spinal pain, and rapidly progressing myelopathy. Magnetic resonance (MR) imaging is the imaging test of choice in humans. Here, we describe the MR imaging features of five dogs with confirmed spinal epidural empyema. The epidural lesions appeared as high or mixed signal masses in T2-weighted (T2W) images. Increased signal within the spinal cord gray matter at the site of the lesion was detected in T2W images in all dogs. Two patterns of enhancement were detected on postcontrast T1-weighted (T1W) images. Mild to moderate peripheral enhancement was seen in three dogs and a diffuse pattern of enhancement was seen in one. Discospondylitis was identified in three dogs on T1W postcontrast images. Decompressive spinal surgery was performed in all dogs. Bacteria isolated from the abnormal epidural tissue were Enterobacter cloacae, coagulase-positive Staphylococci, Pasteurella multocida, and Escherichia coli. In one dog bacteria were not isolated. These MR imaging features, along with appropriate clinical signs, can allow prompt diagnosis and appropriate treatment planning.

Spinal subdural abscess: A rare cause of low back pain

Spinal subdural abscess (SSA) is a rare but well-described entity. It may occur secondary to a systemic infectious focus or following a surgical procedure. There are only two SSA cases in the literature that are unrelated to such conditions and without any well-documented etiology. SSA is a neurosurgical emergency and diagnosis may be difficult. Progressive neurological deficits and severe pain with fever suggest the diagnosis. Surgical drainage and subsequent prompt antimicrobial therapy should be performed without delay. We report a patient with SSA unrelated to any predisposing condition and discuss underlying mechanisms of this disease.

Upper cervical myelopathy due to arachnoiditis and spinal cord tethering from adjacent C-2 osteomyelitis. Case report and review of the literature

Myelopathy caused by a spinal cord infection is typically related to an adjacent compressive lesion such as an epidural abscess. The authors report a case of progressive high cervical myelopathy from spinal cord tethering caused by arachnoiditis related to an adjacent C-2 osteomyelitis. This 70-year-old woman initially presented with a methicillin-sensitive Staphylococcus aureus osteomyelitis involving the C-2 odontoid process. She was treated with appropriate antibiotic therapy but, over the course of 4 weeks, she developed progressive quadriparesis. A magnetic resonance image revealed near-complete resolution of the C-2 osteomyelitis, but new ventral tethering of the cord was observed at the level of the odontoid tip. She subsequently underwent open surgical decompression and cord detethering. Postoperatively she experienced improvement in her symptoms and deficits, which continued to improve 1 year after her surgery. To the authors' knowledge, this is the first reported case of progressive upper cervical myelopathy due to arachnoiditis and cord tethering from an adjacent methicillin-sensitive S. aureus C-2 osteomyelitis.

Clinical assessment and medical treatment of spine infections

Spinal infections affect the vertebral bodies, the intervertebral disks, the spinal canal, and the paravertebral soft tissues and structures. A delay in diagnosis can result in spine deformity, substantial neurologic complications, and even death. Because of this, a high level of awareness is required by physicians in order to diagnose infections of the spine promptly. Advances in medical microbiologic testing and newer imaging methods have contributed considerably to the medical treatment of these infections. Through careful followup, less invasive approaches orchestrated by a multidisciplinary team that includes a spine surgeon, an infectious diseases specialist, and a neuroradiologist may be sufficient to treat patients with these infections. Research done through multidisciplinary collaborations will further advance our knowledge for the successful treatment of spinal infections.

LEVEL OF EVIDENCE

Level V (expert opinion). Please see the Guidelines for Authors for a complete description of levels of evidence.

Epidural abscess causing cauda equina syndrome

BACKGROUND

Spinal epidural abscesses are uncommon but are well documented in the literature as a serious causes of mortality and long-term neurological morbidity.

AIM

We describe a case of a 57-year-old female who presented to Accident and Emergency with an acute exacerbation of long standing mild lower back pain with symptoms of cauda equina syndrome and a systemic infective process.

CONCLUSION

The diagnosis of this condition requires a high index of suspicion. This report demonstrates that with adequate decompression and appropriate antimicrobial treatment a good outcome is achievable.

Spinal epidural abscess: clinical presentation, management, and outcome

BACKGROUND

We sought to describe the clinical characteristics of patients with spinal epidural abscess and to relate presentation and treatment to short-term clinical and neurologic outcome.

METHODS

We retrospectively reviewed the records and radiographic images of all patients admitted to our institution with a diagnosis of spinal epidural abscess between January 1995 and March 2001.

RESULTS

Thirty males and 18 females were admitted with spinal epidural abscess. Median age was 61 years (range, 31-84). Twenty-three of 48 patients were febrile at presentation and the mean white blood cell (WBC) count was 15.5 (range, 4.0-38.7). Twenty-seven patients presented with motor deficits, 17 with pain alone, 2 with sepsis, 1 with dysphagia, and 1 incidentally on spinal imaging. Intravenous drug abuse was the most common risk factor (13 patients) followed by the presence of nonspinal infection, including endocarditis (10 patients). Blood cultures were positive in 29 patients. Staphylococcus aureus was the most common organism cultured from abscesses. Collections were located in the cervical spine in 11 patients, cervicothoracic in 4, thoracic in 7, thoracolumbar in 4, and lumbosacral in 22. One patient harbored both cervical and lumbar epidural abscesses. Twenty-three patients initially received nonoperative therapy with antibiotics alone; 25 underwent urgent surgery. Eleven patients initially treated with antibiotics eventually deteriorated and required delayed surgery. Patients receiving antibiotics suffered a significantly greater number of unfavorable outcomes (clinical deterioration or death) than those in the early surgical group (P < 0.005).

CONCLUSIONS

Patients with spinal epidural abscess may be normothermic and have normal WBC counts. Urgent surgery was more likely to be offered to patients presenting with neurologic deficits than with pain alone. Patients treated without early surgery were significantly more likely to deteriorate and suffer poor outcomes.

General principles in the medical and surgical management of spinal infections: a multidisciplinary approach

OBJECT

Infections along the spinal axis are characterized by an insidious onset, and the resulting delays in diagnosis are associated with serious neurological consequences and even death. Infections of the spine can affect the vertebral bodies, intervertebral discs, spinal canal, and surrounding soft tissues. Neurological dysfunction occurs when the spinal cord becomes compressed, edematous, or ischemic due to compression by abscess or vascular compromise. The aim of this paper was to detail general diagnostic and management principles for this disease.

METHODS

Recent progress in medical technologies, including the development of potent antimicrobial drugs, advanced imaging, and improved surgical methods, have dramatically reduced morbidity and mortality rates for spinal infections; however, debate still exists on the proper management of this disease. In this paper, the authors review the current management protocols for spinal infections at their institution, focusing on medical and surgical treatments for vertebral osteomyelitis, intervertebral disc space infections, and spinal canal and soft-tissue abscesses.

CONCLUSIONS

Technological advances in imaging modalities, pharmaceutics, and surgery have resulted in excellent outcomes and have greatly reduced the morbidity and mortality rates associated with spinal infections. Currently, treatment of spinal infections requires a multidisciplinary team that includes infectious diseases experts, neuroradiologists, and spine surgeons. The key to successful management of spinal infections is early detection.

Spinal epidural abscess: appearance on magnetic resonance imaging as a guide to surgical management

Spinal epidural abscess is associated with considerable rates of morbidity and mortality despite its infrequent occurrence. Advances in magnetic resonance (MR) imaging technology have allowed easier diagnosis of this potentially devastating condition. It is also possible to predict the intraoperative appearance of each case of spinal epidural abscess prior to the procedure, based on the MR findings. Surgical treatment of this condition usually involves extensive decompressive laminectomy, which predisposes patients to spinal instability and deformity. Recent advances in surgical approaches to spinal epidural abscess have included the institution of less invasive techniques to manage this condition, including saline washes of the epidural space through catheters introduced via limited laminotomy. The cases reported here illustrate the ability to predict the intraoperative findings in patients with spinal epidural abscess, and to adjust the surgical approach accordingly to minimize the extent of potentially destabilizing procedures without impinging on the effectiveness of treatment.

Cervical subdural empyema following acupuncture

A review of the literature reveals only a few cases of spinal subdural empyema. Etiologies of spinal subdural empyema include hematogenous spread from skin lesions, systemic sepsis, direct spread from spinal osteomyelitis and complications of discography. However, in this report, we describe a patient who developed spinal subdural empyema following several cervical acupuncture sessions. Operative treatment with adequate laminectomy, removal of abscess, and copious irrigation resulted in good recovery. Microbiologic culture study of pus obtained at surgery was positive for Staphylococcus aureus. The need for sterilization procedures for acupuncture is emphasized and a brief review of the relevant literature is presented.

Spinal epidural abscess in adults

Spinal epidural abscess is a potentially life-threatening disease that can cause paralysis by the accumulation of purulent material in the epidural space. Although modern diagnostic and management methods have improved the prognosis, morbidity and mortality remain significant. Outcome usually is determined by the rapidity of the diagnosis and initiation of appropriate treatment. A high index of suspicion is warranted when a patient presents with spinal pain or a neurologic deficit in conjunction with fever or an elevated erythrocyte sedimentation rate. Gadolinium-enhanced magnetic resonance imaging should be done in suspected cases to localize and define the abscess. For spinal epidural abscess associated with neurologic compromise, the treatment of choice is emergent surgical decompression and débridement (with or without spinal stabilization), followed by long-term antimicrobial therapy. In the absence of a neurologic deficit, medical management is an alternative to surgery when the risk of neurologic complications is low based on the location and morphology of the abscess, immune status of the patient, and virulence of the organism.

Cervicothoracolumbar spinal epidural abscess with tetraparesis. Good recovery after non-surgical treatment with antibiotics and dexamethasone. Case report and review of the literature

We report the conservative treatment of a spinal epidural abscess (SEA) caused by escherichia coli and affecting the anterior epidural space from C2 to L4 in a diabetic, obese patient presenting with tetraparesis. The favourable clinical response to the administration of dexamethasone and antibiotics is described. We review the literature on non-surgical treatment of SEA with special regard to the use of corticosteroids.

Surgical management of spinal epidural abscess: selection of approach based on MRI appearance

Spinal epidural abscess (SEA) is associated with considerable morbidity and mortality despite its infrequent occurrence. The evolution of magnetic resonance imaging has allowed for easier diagnosis of this potentially devastating condition. It is also possible to predict the intraoperative appearance of each individual case of SEA prior to the procedure, based on the MR findings. Surgical treatment of SEA usually involves extensive decompressive laminectomy, predisposing the patient to the development of spinal instability and deformity. Recent advances in surgical approach to SEA have seen the institution of less invasive techniques to manage this condition, including washout of the epidural space with catheters introduced via laminotomy. Our three cases illustrate the ability to predict the intraoperative findings in patients with SEA, and accordingly adjust the surgical approach to minimize the extensiveness of potentially destabilizing procedures, without impinging on the effectiveness of treatment.

Postoperative wound infections of the spine

Postoperative spinal wound infections occur in 1 to 12% of patients. The rate of infection is related to the type and duration of the procedure, comorbidities, nutritional status, and various other risk factors. Antibiotic prophylactic therapy has been clearly shown to decrease the rate of infection dramatically after lumbar surgery. These infections typically manifest with signs and symptoms of wound swelling, erythema, and drainage. Laboratory-detected values such as the erythrocyte sedimentation rate and C-reactive protein can be elevated beyond what is normal for the uncomplicated postoperative course following lumbar surgery, and combined with the clinical symptoms should alert the physician to the possibility of infection. When detected, these infections should be managed aggressively with operative debridment and irrigation, including the deep subfascial layer in all cases except those with clearly demarcated superficial infection. The choice of one versus multiple debridments can be made based on the appearance of the wound, patient factors, and nutritional status. Hardware and incorporated bone graft can be left in place in the majority of cases, adding to stability. Outcomes following aggressive treatment of this complication can be excellent, with no long-term loss of function and complete eradication of the infection.

A comprehensive review of spinal arachnoiditis

Spinal arachnoiditis is an insidious disease caused by an inflammatory process of the arachnoid membrane resulting from many possible causes, such as myelograms with oil-based radiographic contract agents and multiple back surgeries. Diagnosis is based on symptoms and magnetic resonance imaging. Arachnoiditis can also mimic the symptoms of other diseases, such as spinal cord tumors, cauda equina syndrome, arachnoiditis ossificans, and syringomyelia. Unfortunately, there is no cure, only treatment of the chronic symptoms. It is an incurable disease that can cause minor to severe symptoms from unexplained rashes to neurologic defects.

Favorable outcome of long-lasting thoracic spondylodiscitis with spinal epidural abscess induced by Staphylococcus aureus

A favorable outcome in chronic spondylodiscitis with epidural abscess is rare. A 65-year-old woman developed recurrent, localized, thoracic back pain over 2.5 years. Nine months after the onset of the pain, sensory disturbances of the left lower leg occurred. Fourteen months before admission, she developed recurrent fever, bladder dysfunction, and weakness and numbness of both lower legs. An incomplete sensory transverse syndrome with paraparesis was diagnosed. Magnetic resonance imaging of the spine suggested destruction of the T11 vertebral body, with spondylodiscitis of the adjacent discs and an epidural abscess between levels T4 and T9. Laminectomy was immediately performed and the abscess was drained. Culture revealed infection with Staphylococcus aureus. After 10 weeks of therapy, recovery was almost complete. Spondylodiscitis with epidural abscess may have a favorable outcome, even if symptoms start more than 2 years before treatment.

Spinal toxoplasmic arachnoiditis associated with osteoid formation: a rare presentation of toxoplasmosis

STUDY DESIGN

An extremely rare presentation of an isolated spinal toxoplasmic arachnoiditis is described.

OBJECTIVE

To draw attention to the fact that spinal arachnoid membranes may be a potential reservoir for Toxoplasma gondii.

SUMMARY OF BACKGROUND DATA

Central nervous system toxoplasmosis is a common manifestation in patients who are immunodeficient. Reports on the spinal toxoplasmosis are rare and focused on spinal cord involvement.

METHODS

An adult patient presented with symptoms of spastic paraparesis that had begun 13 years before admission. Thoracic spinal magnetic resonance imaging showed small lesions in posterior subarachnoid space at Th7-Th8. A Th7-Th8 laminectomy was performed. Intradural-extramedullary lesions were excised.

RESULTS

Clinical, immunologic, and pathologic examinations showed adhesive spinal arachnoiditis associated with osteoid formation caused by past toxoplasmic infection. There was no impairment of the immunologic defense system.

CONCLUSION

Where no causative factor is found in serious spinal adhesive arachnoiditis, the possibility of spinal toxoplasmosis should also be investigated.

Pyogenic abscess of the filum terminale. Case report

Intradural spinal abscesses are rare. They are predominantly encountered as intramedullary abscesses of the spinal cord and infrequently as subdural lesions. To their knowledge, the authors report the first case of a chronic pyogenic abscess of the terminal filum in an adult woman with kyphoscoliosis who presented with lumbar radiculopathies. Magnetic resonance imaging revealed a partly cystic intradural L3-4 mass that markedly enhanced after contrast administration. Laboratory signs of infection were absent. Intraoperatively a lobulated lesion observed within the terminal filum was tightly attached to neighboring nerve roots by fibrosis. On opening the cyst wall pus was revealed. Histological examination confirmed the diagnosis of a chronic abscess. Microbiological culture detected Staphylococcus aureus. Antibiotic therapy resulted in an uneventful postoperative course, with complete resolution of symptoms and radiologically demonstrated disappearance of the lesion. The pathogenesis and radiological features of the lesion are discussed. Although extremely rare, a pyogenic abscess should be considered in the differential diagnosis of mass lesions of the cauda equina, especially in patients with preexisting spinal abnormalities. Surgical exposure, including drainage and biopsy sampling to rule out underlying tumor, combined with antibiotic treatment result in a favorable outcome.

Management of an Epidural Abscess After Continuous Epidural Catheter Infusion

OBJECTIVE

To increase awareness of the possibility of epidural infection after continuous epidural infusion. Outline the salient diagnostic features of epidural infection. Outline a strategy to manage epidural infection and minimize morbidity.

SETTING

Academic multidisciplinary pain clinic.

PATIENT

A patient with a left knee meniscal tear with a history of Chronic Regional Pain Syndrome Type I (CRPS I) of the left foot.

INTERVENTIONS

Attempted control of CRPS I symptoms with a tunnelled epidural catheter infusion.

RESULTS AND CONCLUSIONS

The patient developed an epidural abscess diagnosed on the 11th postoperative day. The catheter was removed and the patient was treated successfully with intravenous antibiotics.

Spinal epidural abscesses in children: a 15-year experience and review of the literature

We reviewed medical records and laboratory and diagnostic evaluations for 8 pediatric patients with spinal epidural abscesses who were treated during the last 15 years at our institution. Staphylococcus aureus was isolated from 5 of 8 epidural abscesses, including 2 abscesses with methicillin-resistant S. aureus. Unusual isolates were group B Streptococcus in a patient with chronic vesicouretral reflux associated with the posterior urethral valves and Aspergillus flavus in a patient with acute myelogenous leukemia. An analysis incorporating our results and a review of the English-language literature about abscesses in children and adults revealed differences related to age. Abscesses in children were more posterior in epidural location, had greater spinal column extension, and were associated with more favorable clinical outcomes than were abscesses in adults. Magnetic resonance imaging is the diagnostic procedure of choice; however, radionuclide bone scans should be considered for associated distant osteomyelitis in children. Prompt diagnosis and combined medical and surgical treatment remain the cornerstones for the prevention of adverse outcomes.

Spinal epidural abscess in a young child

This is a case report of a spinal epidural abscess, caused by Staphylococcus aureus, in a 3-year-old girl. The child presented with fever and hip pain, but without any neurologic deficit. After normal plain films and a normal bone scan were obtained, the diagnosis was made via magnetic resonance imaging (MRI). The neurosurgery and pediatric infectious disease teams evaluated the patient, and the decision was made to forego surgical drainage and to treat medically with appropriate intravenous and then oral antibiotics. Several months later, the child was doing well without any signs of neurologic sequelae. Because of the rarity of this disease in children, the treatment guidelines are controversial. Many suggest that a spinal epidural abscess must be drained surgically. Our experience adds to the literature a case of a child successfully treated with antibiotics alone. We believe that this success is related to the fact that the child was diagnosed by MRI early in the course of the disease and that she never displayed any neurologic deficits.

Hematogenous pyogenic spinal infections and their surgical management

STUDY DESIGN

Mainly a retrospective study of 101 cases of pyogenic spinal infection, excluding postoperative infections. Data were obtained through medical record review, imaging examination, and patient follow-up evaluation.

SUMMARY OF BACKGROUND DATA

Hematogenous pyogenic spinal infection has been described variously as spondylodiscitis, discitis, vertebral osteomyelitis, and epidural abscess. Recommended treatment options have included conservative methods (antibiotics and bracing) and surgical intervention. However, a comprehensive classification that would aid in diagnosis, treatment planning, and prognosis has not yet been devised.

OBJECTIVES

To analyze the bacteriology, pathologic entities, complications, and results of treatment options for pyogenic spinal infection.

METHOD

All patients received plain radiographs, gadolinium-enhanced magnetic resonance imaging scans, and bone/gallium radionuclide studies. All patients had tissue biopsies. Bacteriology, hematology, and predisposing factors were analyzed. All patients received intravenous and oral antibiotics. A total of 58 patients underwent surgery. Patient outcomes were correlated with clinical status, with treatment method and, where applicable, with location and nature of epidural compression. Statistical analyses were performed.

RESULTS

Spondylodiscitis occurred most commonly with primary epidural abscess, spondylitis, discitis, and pyogenic facet arthropathy, all occurring rarely. Staphylococcus aureus was the main organism. Infection elsewhere was the most common predisposing factor. Leukocyte counts were elevated in 42.6% of spondylodiscitis cases. The erythrocyte sedimentation rate was elevated in all cases of epidural abscess. There were 35 cases of epidural abscess (frank abscess, 29; granulation tissue, 6). Epidural abscess complicating spondylodiscitis occurred most often in the cervical spine, followed by thoracic and lumbar areas. The rate of paraplegia or paraparesis also was highest in cervical and thoracic regions. There were no cases of quadriplegia. All patients with either epidural granulation tissue or paraparesis recovered completely after surgical decompression. Only 18% of patients with frank epidural abscess and 23% of patients with paralysis recovered completely after surgical decompression. Patients with spondylodiscitis who were treated nonsurgically reported residual back pain more often (64%) than patients treated surgically (26.3%).

CONCLUSIONS

Pyogenic spinal infection can be thought of as a spectrum of disease comprising spondylitis, discitis, spondylodiscitis, pyogenic facet arthropathy, and epidural abscess. Spondylodiscitis is more prone to develop epidural abscesses in the cervical spine (90%) than the thoracic (33.3%) or lumbar (23.6%) areas. Thecal sac neurocompression has a greater chance of causing neurologic deficit in the thoracic spine (81.8%). Treatment of neurologic deficit caused by epidural abscess is prompt surgical decompression, with or without fusion. Patients with frank abscess had less favorable outcomes than those with granulation tissue, and paraplegia responded to treatment more poorly than paraparesis. Surgery was preferable to nonsurgical treatment for improving back pain.

Neurosurgical emergencies

The neurologic patient is considered a neurosurgical emergency when delay of treatment may influence the patient's outcome. Diseases of the spinal cord, brain, and peripheral nerves are presented in this article. Diagnostic tools (i.e., advanced imaging and electrophysiologic tests), differential diagnoses, treatment options (conventional and controversial), whether the patient requires surgery, and the optimal time for surgical intervention are discussed.

Emergency department evaluation and treatment of back pain

Patients with back pain commonly present in the emergency department for evaluation and treatment. Because it is a common syndrome with a generally benign origin, the examiner may overlook markers of serious disease. This article reviews the important historical and physical factors to consider, with an emphasis on the red flags of serious disease. This article also reviews the management of acute lumbosacral strain, sciatica, and disc herniation, cauda equina syndrome and spinal cord compression, and back pain in the patient with a history of cancer.