Imaging of spinal infections

Magnetic resonance imaging findings in central nervous system tuberculosis: A pictorial review

Central nervous system (CNS) tuberculosis is a post-primary form of tuberculosis. It has high mortality and morbidity rates despite early diagnosis and treatment. CNS tuberculosis can manifest as subacute/chronic meningitis, parenchymal tuberculous lesions, and spinal tuberculosis. Hematogenous spread of tuberculous bacilli to the brain results in the development of so called "rich foci" on the pial surface, ependyma, and grey-white matter junction. Rupture of these "rich foci" into the subarachnoid space triggers an intense granulomatous inflammatory reaction. Tuberculous meningitis can manifest as leptomeningitis or pachymeningitis. Intracranial parenchymal tuberculous lesions may present as tuberculoma, tuberculous abscess, cerebritis, rhombencephalitis, and encephalopathy, with atypical presentations not uncommon. Complications of CNS tuberculosis encompass hydrocephalus, syrinx formation, vasculitis, infarcts, neuritis, and enduring neurological deficits. Post-contrast 3D fluid-attenuated inversion recovery (FLAIR) and post-contrast T1 spin-echo sequences excel in detecting tuberculous meningitis compared to other conventional magnetic resonance imaging (MRI) sequences. In proton magnetic resonance spectroscopy (PMRS), the presence of a lipid peak at 1.3 ppm is indicative of tuberculous lesions. Magnetization transfer (MT) imaging enhances the detection of tuberculous lesions, as the magnetization transfer ratio (MTR) of tuberculous pathologies, owing to their high lipid content, is lower than that in bacterial or fungal pathologies and higher than that in viral pathologies. This review article delves into the various typical and atypical imaging presentations of CNS tuberculosis in MRI, along with recent advances in imaging techniques.

Infectious Myelitis

Myelitis is an extensive group of pathologies, including inflammatory, demyelinating, and infectious disorders, sometimes mimicking tumors. This article will discuss infectious myelitis, mainly the patterns of spinal cord involvement caused by each infectious agent and the contribution of magnetic resonance imaging as a major tool to establish the specific diagnosis.

Isolated cryptococcosis of a lumbar vertebra in an immunocompetent patient: A case report and literature review

Background

Cryptococcus, a kind of fungus, can be found in soil, decayed wood, and avian excreta. Immunocompromised patients are prone to infection caused by Cryptococcus, and the lungs and central nervous system are the main target organs. Cryptococcosis rarely occurs in the lumbar vertebra or in immunocompetent patients.

Case presentation

A 40-year-old adult male with isolated lumbar vertebra cryptococcosis at the L4 vertebra underwent successful lesion removal surgery performed via the posterior approach and postoperative administration of an antifungal agent. At the 12-month follow-up, the patient's pain was relieved, and his motor function had improved. Isolated Cryptococcus vertebrae infection is a rare infectious disease.

Conclusions

A needle biopsy can confirm the diagnosis of Cryptococcus infection. When patients present with unbearable symptoms of nerve compression, posterior depuration combined with postoperative antifungal agents is a good option.

International Framework for Red Flags for Potential Serious Spinal Pathologies

The International Federation of Orthopaedic Manipulative Physical Therapists (IFOMPT) led the development of a framework to help clinicians assess and manage people who may have serious spinal pathology. While rare, serious spinal pathology can have devastating and life-changing or life-limiting consequences, and must be identified early and managed appropriately. Red flags (signs and symptoms that might raise suspicion of serious spinal pathology) have historically been used by clinicians to identify serious spinal pathology. Currently, there is an absence of high-quality evidence for the diagnostic accuracy of most red flags. This framework is intended to provide a clinical-reasoning pathway to clarify the role of red flags. J Orthop Sports Phys Ther 2020;50(7):350-372. Epub 21 May 2020. doi:10.2519/jospt.2020.9971.

Red flags for the early detection of spinal infection in back pain patients

BACKGROUND

Red flags are signs and symptoms that are possible indicators of serious spinal pathology. There is limited evidence or guidance on how red flags should be used in practice. Due to the lack of robust evidence for many red flags their use has been questioned. The aim was to conduct a systematic review specifically reporting on studies that evaluated the diagnostic accuracy of red flags for Spinal Infection in patients with low back pain.

METHODS

Searches were carried out to identify the literature from inception to March 2019. The databases searched were Medline, CINHAL Plus, Web of Science, Embase, Cochrane, Pedro, OpenGrey and Grey Literature Report. Two reviewers screened article texts, one reviewer extracted data and details of each study, a second reviewer independently checked a random sample of the data extracted.

RESULTS

Forty papers met the eligibility criteria. A total of 2224 cases of spinal infection were identified, of which 1385 (62%) were men and 773 (38%) were women mean age of 55 (± 8) years. In total there were 46 items, 23 determinants and 23 clinical features. Spinal pain (72%) and fever (55%) were the most common clinical features, Diabetes (18%) and IV drug use (9%) were the most occurring determinants. MRI was the most used radiological test and Staphylococcus aureus (27%), Mycobacterium tuberculosis (12%) were the most common microorganisms detected in cases.

CONCLUSION

The current evidence surrounding red flags for spinal infection remains small, it was not possible to assess the diagnostic accuracy of red flags for spinal infection, as such, a descriptive review reporting the characteristics of those presenting with spinal infection was carried out. In our review, spinal infection was common in those who had conditions associated with immunosuppression. Additionally, the most frequently reported clinical feature was the classic triad of spinal pain, fever and neurological dysfunction. This is an Open Access article distributed in accordance with the Creative Commons Attribution Non-Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

Challenges in diagnosis of spinal epidural abscess: A case report

RATIONALE

Spinal epidural abscess (SEA) is a rare condition that shows a high prevalence in immunocompromised patients. The clinical presentation of SEA includes the "classic triad" of pain, fever, and neurological dysfunction. However, these nonspecific features can lead to a high rate of misdiagnosis. SEA may lead to paralysis or even death; thus, prognosis of these patients remains unfavorable.

PATIENT CONCERNS

We report a case of a multilevel (T6-T12) SEA in a 22-year-old woman.

DIAGNOSIS

The patient was initially diagnosed with spinal tuberculosis at a local hospital based on a history of tuberculosis exposure, as well as radiography and computed tomography. Histopathological examination of the tissue resected during laminectomy confirmed the diagnosis of SEA in this patient.

INTERVENTIONS

The patient underwent multilevel laminectomy combined with long-term antibiotic therapy.

OUTCOMES

Physical examination performed 16 months postoperatively revealed that superficial and deep sensation was restored to normal levels in the lower extremities with improvement in the patient's motor function (muscle strength 2/5).

LESSONS

This case report indicates that whole spine magnetic resonance imaging is warranted in patients with SEA and that prompt surgical intervention is important at symptom onset. Long-term antibiotic therapy is also essential postoperatively.

Recent Developments in the Treatment of Spinal Epidural Abscesses

Spinal epidural abscess (SEA) is a serious condition that can be challenging to diagnose due to nonspecific symptomology and delayed presentation. Despite this, it requires prompt recognition and management in order to prevent permanent neurologic sequelae. Several recent studies have improved our understanding of SEA. Herein, we summarize the recent literature from the past 10 years relevant to SEA diagnosis, management and outcome. While surgical care remains the mainstay of treatment, a select subset of SEA patients may be managed without operative intervention. Multidisciplinary management involves internal medicine, infectious disease, critical care, and spine surgeons in order to optimize care.

Practical Considerations in Sepsis Resuscitation

BACKGROUND

Sepsis is a common condition managed in the emergency department, and the majority of patients respond to resuscitation measures, including antibiotics and i.v. fluids. However, a proportion of patients will fail to respond to standard treatment.

OBJECTIVE

This review elucidates practical considerations for management of sepsis in patients who fail to respond to standard treatment.

DISCUSSION

Early goal-directed therapy revolutionized sepsis management. However, there is a paucity of literature that provides a well-defined treatment algorithm for patients who fail to improve with therapy. Refractory shock can be defined as continued patient hemodynamic instability (mean arterial pressure, ≤ 65 mm Hg, lactate ≥ 4 mmol/L, altered mental status) after adequate fluid loading (at least 30 mL/kg i.v.), the use of two vasopressors (with one as norepinephrine), and provision of antibiotics. When a lack of improvement is evident in the early stages of resuscitation, systematically considering source control, appropriate volume resuscitation, adequate antimicrobial coverage, vasopressor selection, presence of metabolic pathology, and complications of resuscitation, such as abdominal compartment syndrome and respiratory failure, allow emergency physicians to address the entire clinical scenario.

CONCLUSIONS

The care of sepsis has experienced many changes in recent years. Care of the patient with sepsis who is not responding appropriately to initial resuscitation is troublesome for emergency physicians. This review provides practical considerations for resuscitation of the patient with septic shock. When a septic patient is refractory to standard therapy, systematically evaluating the patient and clinical course may lead to improved outcomes.

Imaging of Spinal Manifestations of Hematological Disorders

Imaging manifestations of hematological diseases and their potential complications are broad, and there may be significant overlap in features of various disease processes. Knowledge of appropriate choice of imaging test, pertinent imaging patterns, and pathophysiology of disease can help the reader increase specificity in the diagnosis and treatment of the patient. Most importantly, we encourage readers of this review to engage their radiologists during the diagnostic, treatment, and management phases of care delivery.

Upper Cervical Epidural Abscess in Clinical Practice: Diagnosis and Management

Study Design Narrative review. Objective Upper cervical epidural abscess (UCEA) is a rare surgical emergency. Despite increasing incidence, uncertainty remains as to how it should initially be managed. Risk factors for UCEA include immunocompromised hosts, diabetes mellitus, and intravenous drug use. Our objective is to provide a comprehensive overview of the literature including the history, clinical manifestations, diagnosis, and management of UCEA. Methods Using PubMed, studies published prior to 2015 were analyzed. We used the keywords "Upper cervical epidural abscess," "C1 osteomyelitis," "C2 osteomyelitis," "C1 epidural abscess," "C2 epidural abscess." We excluded cases with tuberculosis. Results The review addresses epidemiology, etiology, imaging, microbiology, and diagnosis of this condition. We also address the nonoperative and operative management options and the relative indications for each as reviewed in the literature. Conclusion A high index of suspicion is required to diagnose this rare condition with magnetic resonance imaging being the imaging modality of choice. There has been a shift toward surgical management of this condition in recent times, with favorable outcomes.

Spinal brucellosis

Spinal involvement in human brucellosis is a common condition and a significant cause of morbidity and mortality, particularly in endemic areas, because it is often associated with therapeutic failure. Most chronic brucellosis cases are the result of inadequate treatment of the initial episode. Recognition of spinal brucellosis is challenging. Early diagnosis is important to ensure proper treatment and decrease morbidity and mortality. Radiologic evaluation has gained importance in diagnosis and treatment planning, including interventional procedures and monitoring of all spinal infections.

Overview of the complications and sequelae in spinal infections

Spondylitis or infection of the spine is a spectrum of diseases involving the bone, disks, and/or ligaments. Because of a significant increase in the immunocompromised patient population, spinal infections are a growing and changing group of conditions, making the diagnosis based on imaging more challenging. Most cases of spinal infections are pyogenic and occur after hematogeneous spread of an infection located elsewhere in the body. A prompt diagnosis remains crucial and MR imaging remains the cornerstone in the diagnosis. This article provides a pictorial overview of the complications and sequelae in spinal infections in general. Discussed are postoperative infections, extraspinal spread of infection, fractures and malformations, and neurologic complications.

Imaging findings of cryptococcal infection of the thoracic spine

Cryptococcosis with thoracic spine involvement is extremely rare, with most cases occurring in immunosuppressed patients. We report a case of cryptococcosis of the thoracic vertebrae confirmed by histopathology. The immunocompetence of the patient is a most interesting feature of this case. Laboratory investigations were normal, but the erythrocyte sedimentation rate was raised. A computed tomography scan showed an eccentric lytic lesion with a clear boundary at T2-T3. Magnetic resonance imaging showed the endplates of the T2 and T3 vertebral bodies to be involved, but without significant loss of the intervertebral disk height. A prespinal and large paraspinal soft tissue component was spreading along T1-T4, and the pleura and dural sac at the level of T2-T3 had thickened abnormally. (18)F-fluorodeoxyglucose positron emission tomography/computed tomography showed abnormal uptake in the lesion. The above-mentioned clinical and imaging information will help improve our understanding of this rare disease.

Pyogenic and non-pyogenic spinal infections: emphasis on diffusion-weighted imaging for the detection of abscesses and pus collections

The incidence of spinal infections has increased in the past two decades, owing to the increasing number of elderly patients, immunocompromised conditions, spinal surgery and instrumentation, vascular access and intravenous drug use. Conventional MRI is the gold standard for diagnostic imaging; however, there are still a significant number of misdiagnosed cases. Diffusion-weighted imaging (DWI) with a b-value of 1000 and apparent diffusion coefficient (ADC) maps provide early and accurate detection of abscess and pus collection. Pyogenic infections are classified into four types of extension based on MRI and DWI findings: (1) epidural/paraspinal abscess with spondylodiscitis, (2) epidural/paraspinal abscess with facet joint infection, (3) epidural/paraspinal abscess without concomitant spondylodiscitis or facet joint infection and (4) intradural abscess (subdural abscess, purulent meningitis and spinal cord abscess). DWI easily detects abscesses and demonstrates the extension, multiplicity and remote disseminated infection. DWI is often a key image in the differential diagnosis. Important differential diagnoses include epidural, subdural or subarachnoid haemorrhage, cerebrospinal fluid leak, disc herniation, synovial cyst, granulation tissue, intra- or extradural tumour and post-surgical fluid collections. DWI and the ADC values are affected by susceptibility artefacts, incomplete fat suppression and volume-averaging artefacts. Recognition of artefacts is essential when interpreting DWI of spinal and paraspinal infections. DWI is not only useful for the diagnosis but also for the treatment planning of pyogenic and non-pyogenic spinal infections.

Spinal epidural abscess and paralytic mechanisms

PURPOSE OF REVIEW

The incidence of spinal epidural abscess is increasing, and the understanding of the pathophysiology is evolving. Better understanding of the pathophysiology, specifically the role of ischemia, warrants a change in therapy.

RECENT FINDINGS

Paralysis in spinal epidural abscess may be the result of spinal cord compression, spinal cord arterial and/or venous ischemia and thrombophlebitis or a combination of these.

SUMMARY

Recent evidence indicates the following areas of investigation and management can improve outcome in spinal epidural abscess: minimally invasive surgery early versus medical management when there are no significant neurological deficits, neuroradiologic arterial evaluation with therapies directed at vascular ischemia and thrombosis, and aggressive rehabilitation.

Imaging of spine infection

This article reviews the imaging and relevant clinical details of infection of the extradural spine. Spine infections are increasing in incidence and in frequency of diagnosis. They are clinically important despite their relative rarity, because they may be life-threatening, and because early diagnosis leads to improved outcomes. The focus is on pyogenic spondylodiscitis. The also typically pyogenic conditions of epidural and subdural abscess, facet joint infection, and pyomyositis are discussed. Nonpyogenic, granulomatous infections are also addressed. Magnetic resonance imaging is emphasized. The radiologist's role in performing minimally invasive sampling procedures is highlighted.

Avoiding misdiagnosis in patients with neurological emergencies

Approximately 5% of patients presenting to emergency departments have neurological symptoms. The most common symptoms or diagnoses include headache, dizziness, back pain, weakness, and seizure disorder. Little is known about the actual misdiagnosis of these patients, which can have disastrous consequences for both the patients and the physicians. This paper reviews the existing literature about the misdiagnosis of neurological emergencies and analyzes the reason behind the misdiagnosis by specific presenting complaint. Our goal is to help emergency physicians and other providers reduce diagnostic error, understand how these errors are made, and improve patient care.

Hematogenous spinal infection in central Greece

STUDY DESIGN

We retrospectively analyzed spinal infection (SpI), in a teaching Hospital, in Central Greece.

OBJECTIVE

To study presentation, etiology, and outcome of SpI in Central Greece.

SUMMARY OF BACKGROUND DATA

SpI most frequently involves the intervertebral disc and adjacent vertebral bodies and can cause neurologic impairment.

METHODS

Thirty three patients (23 men; age [mean +/- standard deviation], 60.6 +/- 11.3 years; disease duration, 44.5 [+/-54.7] days) hospitalized with SpI between January 2000 and December 2007 were included in the study. All patients had magnetic resonance imaging of the spine.

RESULTS

Nineteen patients had pyogenic SpI (57.6%) and 14 patients had granulomatous SpI, 11 due to Brucella spp (34.4%), 3 due to Mycobacterium tuberculosis (9.4%). Staphylococcus aureus was the most frequent cause of pyogenic SpI, and spondylodiscitis (SpD) was the most frequent localization. Epidural entension was found in 8 of 17 pyogenic SpD and in 2 of 11 brucellar SpD patients. Subdural extension was detected in 3 patients with pyogenic SpD. Blood cultures were positive in 17 of 19 patients with pyogenic SpI. Two patients had concomitant endocarditis (staphylococcal 1, enterococcal 1). The most common associated disease was diabetes mellitus. All but 2 patients received medical treatment alone. Two patients died of uncontrollable sepsis.

CONCLUSION

Back pain in presence of fever, constitutional symptoms, and/or high inflammation markers should alert physicians for spinal infection. In endemic areas, Brucella is a frequent cause of SpI.

Spontaneous spondylodiscitis: presentation, risk factors, diagnosis, management, and outcome

BACKGROUND

Spontaneous spondylodiscitis is an uncommon disease, which may result in serious complications with potentially high morbidity and mortality. We conducted a prospective case study over a 2-year period in order to analyze the clinical features, approaches to management, and outcome of spondylodiscitis.

METHODS

Eight consecutive patients (four men, four women; age range 53-82 years) suffering from spondylodiscitis were identified during the study period. Parameters recorded included: demographics, past medical history, predisposing factors, presenting signs and symptoms, spinal level and extension of the infection, laboratory indices of inflammation, microbiological testing, radiological assessment, kind and duration of treatment, follow-up magnetic resonance imaging (MRI) studies, and outcome.

RESULTS

Duration of symptoms varied from 14 to 90 days. All patients had back pain; fever>or=38 degrees C was present in 5/8 (62.5%) and neurological findings in 6/8 (75%). Diabetes mellitus was identified in six (75%). Most of the patients had elevated laboratory markers of inflammation. At the initial MRI, 12 anatomical levels were found. The microorganism was identified in 7/8 by blood or bone marrow cultures (50% Staphylococcus aureus). None of the patients underwent surgical intervention. Seven patients (87.5%) recovered to full activity; follow-up MRI study results were not always in parallel with the clinical improvement of patients.

CONCLUSIONS

Spontaneous spondylodiscitis should be considered in every patient with back pain accompanied by fever and laboratory markers of inflammation. The major predisposing risk factor seems to be uncontrolled diabetes. MRI appears to be the method of choice for confirming diagnosis. Timely and accurate diagnosis along with prompt administration of antibiotics appears mandatory for a favorable outcome and avoidance of surgical intervention.