Neuromelioidosis: Craniospinal MRI Findings in Burkholderia pseudomallei Infection

Multi-systemic melioidosis in a patient with type 2 diabetes in non-endemic areas: A case report and review of literature

BACKGROUND

Melioidosis, an infectious disease caused by Burkholderia pseudomallei (B. pseudomallei), occurs endemically in Southeast Asia and Northern Australia and is a serious opportunistic infection associated with a high mortality rate.

CASE SUMMARY

A 58-year-old woman presented with scattered erythema on the skin of her limbs, followed by fever and seizures. B. pseudomallei was isolated successively from the patient's urine, blood, and pus. Magnetic resonance imaging showed abscess formation involving the right forehead and the right frontal region. Subsequently, abscess resection and drainage were performed. The patient showed no signs of relapse after 4 months of follow-up visits post-treatment.

CONCLUSION

We present here a unique case of multi-systemic melioidosis that occurs in non-endemic regions in a patient who had no recent travel history. Hence, it is critical to enhance awareness of melioidosis in non-endemic regions.

Case report long segment myelitis secondary to neuro melioidosis

Background

Neuro-melioidosis, comprising 4% of all cases of melioidosis carries a risk of high morbidity and mortality. We describe two Sri Lankan patients presenting with long segment myelitis secondary to melioidosis.

Case presentation

Case 1: 47-year-old male presented with right side hemiparesis which progressed rapidly to quadriparesis. Initial cerebro spinal fluid (CSF) analysis revealed protein 76 mg/dl and glucose 72 mg/dl but without a cellular reaction. MRI spine revealed long segment myelitis with contrast enhancement. The patient was treated with intravenous methyl prednisolone pulses (IV MPP) and plasma exchanges(PLEX) on suspicion of an immune mediated myelitis but without success. A repeat MRI revealed high signal changes in the brain stem and along the entire spinal cord with contrast enhancement. MRI brain after treatment with MPP/PLEX showed enhancing hyper intensities along the corticospinal tracts. The repeat CSF revealed protein 1187 mg/dl, glucose 78 mg/dl, lymphocytes 1600/mm3 and neutrophils 10,200/mm3. CSF culture has become positive for Burkholderia pseudomallei. Serum melioidosis antibody titre was 1: 320. He was started on IV meropenem with oral cotrimoxazole for 12 weeks followed by oral co trimoxazole. But he had poor clinical recovery.

Case 2: 47-year-old female presented with bilateral lower limb weakness for 1-week duration. On examination, she had flaccid paraparesis with a sensory level at T11. Inflammatory markers were elevated. CSF analysis revealed protein 50 mg/dl with lymphocytes 172/mm3. MRI pan spine revealed a long segment myelitis. Serum melioidosis antibody titre was 1: 640. She was treated with IV meropenem for 8 weeks followed by oral co-trimoxazole with an excellent clinical and radiological response.

Conclusion

Numerous neurological manifestations have been described with melioidosis, however long segment myelitis with a positive CSF culture is not yet reported. These cases signify the importance of considering melioidosis as a differential in patients with long segment myelitis especially in endemic areas.

Magnetic resonance imaging patterns of paediatric brain infections: a pictorial review based on the Western Australian experience

Paediatric brain infections are relatively uncommon, but it is important for radiologists to recognise the disease and provide accurate differential diagnoses. Magnetic resonance imaging (MRI) plays an important role in determining the most likely causative pathogen—either in the setting of an unwell child with acute infectious encephalitis, or in the evaluation of a child for sequela of prior infection. Image analysis can, however, be difficult since a particular pathogen can cause variable MRI findings across different geographic environments, and conversely, a particular appearance on MRI may be caused by a variety of pathogens. This educational review aims to identify some of the key MRI patterns seen in paediatric brain infections and present example cases encountered in Western Australia. Based on (i) the predominant type of signal abnormality (restricted diffusion versus T2 hyperintensity) and (ii) the distribution of signal abnormality throughout the brain, this review presents a framework of six key MRI patterns seen in paediatric brain infections, with an emphasis on acute infectious encephalitis. There is general utility to these MRI patterns—each suggestive of a group of likely diagnostic possibilities which can be calibrated according to institution and local environment. The pattern-based framework of this review can be easily transitioned into daily radiological practice, and we hope it facilitates the formation of accurate differential diagnoses in paediatric brain infections.

Case report: First case of neuromelioidosis in Europe: CNS infection caused by Burkholderia pseudomallei

Neuromelioidosis is a rare CNS infection caused by Burkholderia pseudomallei and is characterized by high morbidity and mortality. Our report presents the diagnostic and therapeutic approach of the first case of neuromelioidosis confirmed in Europe. A 47-year-old man with a medical history of recurrent otitis with otorrhea and fever after tympanoplasty and radical cavity revision operation on the left ear was admitted with headache, decreased level of consciousness, dysarthria, left-sided hemiparesis, and urinary incontinence. After extensive investigations including MRI, microbiological, serological, and CSF analyses, and, ultimately, brain biopsy, a diagnosis of neuromelioidosis was established. Despite antibiotic treatment, the patient showed no clinical improvement and remained in a severely compromised neurological state under mandatory mechanical ventilation. Neuromelioidosis can pose a diagnostic challenge requiring an extensive diagnostic evaluation because of its uncommon clinical and radiological presentations.

Melioidosis of the central nervous system; impact of the bimABm allele on patient presentation and outcome

BACKGROUND

The autotransporter protein Burkholderia intracellular motility A (BimA) facilitates the entry of Burkholderia pseudomallei into the central nervous system (CNS) in mouse models of melioidosis. Its role in the pathogenesis of human cases of CNS melioidosis is incompletely defined.

METHODS

Consecutive culture-confirmed cases of melioidosis at two sites in tropical Australia after 1989 were reviewed. Demographic, clinical and radiological data of the patients with CNS melioidosis were recorded. The bimA allele (bimABm or bimABp) of the B. pseudomallei isolated from each patient was determined.

RESULTS

Of the 1587 cases diagnosed at the two sites during the study period, 52 (3.3%) had confirmed CNS melioidosis; 20 (38.5%) had a brain abscess, 18 (34.6%) had encephalomyelitis, 4 (7.7%) had isolated meningitis and 10 (19.2%) had extra-meningeal disease. Among the 52 patients, there were 8 (15.4%) deaths; 17/44 (38.6%) survivors had residual disability. The bimA allele was characterized in 47/52; 17/47 (36.2%) had the bimABm allele and 30 (63.8%) had the bimABp allele. Patients with a bimABm variant were more likely to have a predominantly neurological presentation (odds ratio (OR) (95% confidence interval (CI)): 5.60 (1.52-20.61), p=0.01), to have brainstem involvement (OR (95%CI): 7.33 (1.92-27.95), p=0.004) and to have encephalomyelitis (OR (95%CI): 4.69 (1.30-16.95), p=0.02. Patients with a bimABm variant were more likely to die or have residual disability (odds ratio (95%CI): 4.88 (1.28-18.57), p=0.01).

CONCLUSIONS

The bimA allele of B. pseudomallei has a significant impact on the clinical presentation and outcome of patients with CNS melioidosis.

Isolated Myelitis and Intramedullary Spinal Cord Abscess in Melioidosis-A Case Report

Neuromelioidosis is a severe tropical infection with high morbidity and mortality. Isolated myelitis is an extremely rare manifestation of melioidosis which may evade diagnosis. We report a 69-year-old diabetic male patient who presented with acute flaccid paraplegia and longitudinally extensive myelitis and no systemic symptoms. MRI of spinal cord showed lower dorsal cord and conus T2 hyperintensity and microabscesses with dural enhancement. The diagnosis was clinched with blood culture growing Burkholderia pseudomallei. He rapidly developed colitis, septicemia and multiorgan dysfunction and succumbed to the illness in spite of antibiotics and aggressive supportive care. The case highlights that melioidosis should be considered as a differential diagnosis of infectious myelitis, especially in the tropics. Presence of a neutrophilic blood and cerebrospinal fluid picture and microabscesses in spinal cord are important diagnostic clues. The outcome is dismal unless the diagnosis is considered early in the disease course and managed expeditiously with sensitive antibiotics.

Epidemiology of Neuromelioidosis in Asia-Pacific: A Systematic Review

Introduction: Neuromelioidosis is a rare complication of melioidosis caused by Burkholderia pseudomallei, a Gram-negative bacterium commonly found in soil and surface water. Although cerebral involvement of melioidosis comprises only 4% of total complications, it significantly impacts mortality and morbidity. This study aims to perform a systematic review on various neurological complications of melioidosis in the Asia-Pacific region within the previous 5 years. Method: Systematic search was performed in PubMed, Web of Science databases and Google Scholar on neuromelioidosis complications published from 2015-2019. Results: Central nervous system (CNS) complications comprise 5% of all cases of melioidosis. 16 selected articles were analysed based on its risk factors like diabetes mellitus, chronic renal and lung disease, alcohol abuse, and immunosuppression. Neuromelioidosis is detected 6-14 days after the first presentation and confirmed by detailed investigations. Radioimaging helps to differentiate neuromelioidosis from other diagnoses such as meningitis or brain abscess. The majority of literature recommended 2-week intensive Ceftazidime or Meropenem therapy, followed by 3–6 months Trimethoprim and Sulfamethoxazole oral eradication therapy. Conclusion: Neuromelioidosis is rare, with relatively nonspecific CNS clinical features. Patients or travelers from endemic areas with risk factors should be treated cautiously. Radioimaging modalities aid early microbiological sampling and appropriate antibiotic therapy.

Neurological Melioidosis Presenting as Rhombencephalitis, Optic Neuritis, and Scalp Abscess with Meningitis: A Case Series from Southern India

Melioidosis is an under recognized infectious disease which may rarely present with neurological involvement. Neurological melioidosis has protean manifestations, and in this case series we present 3 patients diagnosed from a single center in southern India. The clinical presentation of the patients we describe includes rhomb-encephalitis, scalp infection with subdural and meningeal involvement, and optic neuritis associated with pulmonary melioidosis. We discuss the possible mechanism of involvement of the nervous system, and the recommended treatment. Diagnosis of melioidosis requires a high index of suspicion and should be considered in endemic areas. Through this series we hope to improve the awareness of this infection and its neurological presentation.

Neuromelioidosis: A Single-Center Experience with Emphasis on Imaging

Introduction  Infection with Burkholderia pseudomallei , a gram-negative bacterium found in soil and surface water, is termed melioidosis and is commonly reported to occur in Southeast Asia and Northern Australia, where it is endemic. It is being increasingly reported in India, and transmission occurs through inhalation, inoculation, and ingestion. The neuroparenchyma, the adjacent soft tissue, and bone are known to be affected in both the acute and chronic disease forms. Involvement of these structures is rare but causes significant mortality and morbidity.

Material and Methods  Eighteen culture-proven cases of neuromelioidosis were identified between January 2008 and December 2019. The patients were retrospectively identified via search of the hospital’s electronic database.

Results  Cranial disease was in the form of parenchymal abscesses ( n = 4), cerebritis/encephalitis ( n = 5), and extradural ( n = 4) and dural disease ( n = 1). Acute myelitis ( n = 1) and spondylodiscitis ( n = 3) were seen in the spinal disease form. Neuroparenchymal involvement ranged from cerebritis/encephalitis to early and mature parenchymal abscesses. Extradural involvement was in the form of extradural abscesses and/or thick irregular enhancement in the extradural region. Early diagnosis and initiation of appropriate therapy had favorable outcomes in 15 out of 18 patients. Two patients with parenchymal abscesses and one with myelitis succumbed to the illness.

Conclusion  Neuromelioidosis is a rare manifestation of melioidosis with significant morbidity and mortality, necessitating a high index of clinical suspicion, especially if there has been travel to endemic regions. Imaging plays a key role in facilitating early diagnosis and initiation of therapy.

Case Report: Ascending Myelo-Encephalitis after a Penetrating Injury to the Foot: An Atypical Case of Neuromelioidosis

Organisms penetrate the central nervous system (CNS) via three routes. The commonest is the hematogenous route, and other routes include contiguous or penetrating injury or rarely via retrograde axoplasmic route. Although the axoplasmic highway is often used by viruses, only a few bacteria are known to penetrate the CNS via this route. We present a 57-year-old man who developed a penetrating injury while working in a field. Over the next 4 months, he developed pain at the site of the poorly healing wound, which ascended up the right leg and presented as a conus-cauda syndrome. Magnetic resonance imaging (MRI) showed an enhancing intradural intramedullary enhancing lesion in the conus on the right side with cord edema from D11 to L1 level. Extensive evaluation was negative, and he continued to progress to holocord myelitis and developed bilateral corticospinal tract lesions ("tractopathy") in the brain stem and internal capsule. He died after developing a right-sided cerebritis with mass effect. Tissue biopsy from the brain at the time of decompressive craniectomy grew Burkholderia pseudomallei and confirmed a diagnosis of neuromelioidosis (NM). We reviewed the literature for NM, its variable presentations, and the concept of an "infectious tractopathy" and imaging findings which could generate suspicion of this entity.

Melioidosis of the nervous system: atypical presentation of a rare disease in a 48-year-old man

A 48-year-old man who worked in mining in remote, northern Australia was transferred from a rural hospital 5 days after the onset of headaches, subjective fevers and flaccid paralysis of the left upper limb. Initial investigations demonstrated inflammatory cerebrospinal fluid (CSF) changes and a longitudinally extensive cervical cord lesion. Given two serial negative blood and CSF cultures, he was treated as inflammatory myelitis with intravenous methylprednisolone. Despite the initial improvement in pain and left arm power, the patient's neurological deficit plateaued and then deteriorated with worsening neck pain, diaphragmatic dysfunction and dysphagia requiring intubation and respiratory support. A third CSF culture isolated Burkholderia pseudomallei confirming a diagnosis of neuro-melioidosis. Repeat imaging revealed the rostral extension of the original spinal cord lesion into the medulla and pons. Over the next 4 weeks, the patient's neurological deficits slowly improved with continued intravenous antibiotic therapy with meropenem and oral trimethoprim/sulfamethoxazole.

Multinucleated Giant Cell Formation as a Portal to Chronic Bacterial Infections

This review provides a snapshot of chronic bacterial infections through the lens of Burkholderia pseudomallei and detailing its ability to establish multi-nucleated giant cells (MNGC) within the host, potentially leading to the formation of pyogranulomatous lesions. We explore the role of MNGC in melioidosis disease progression and pathology by comparing the similarities and differences of melioidosis to tuberculosis, outline the concerted events in pathogenesis that lead to MNGC formation, discuss the factors that influence MNGC formation, and consider how they fit into clinical findings reported in chronic cases. Finally, we speculate about future models and techniques that can be used to delineate the mechanisms of MNGC formation and function.

Human Melioidosis

The causative agent of melioidosis, Burkholderia pseudomallei, a tier 1 select agent, is endemic in Southeast Asia and northern Australia, with increased incidence associated with high levels of rainfall. Increasing reports of this condition have occurred worldwide, with estimates of up to 165,000 cases and 89,000 deaths per year. The ecological niche of the organism has yet to be clearly defined, although the organism is associated with soil and water. The culture of appropriate clinical material remains the mainstay of laboratory diagnosis. Identification is best done by phenotypic methods, although mass spectrometric methods have been described. Serology has a limited diagnostic role. Direct molecular and antigen detection methods have limited availability and sensitivity. Clinical presentations of melioidosis range from acute bacteremic pneumonia to disseminated visceral abscesses and localized infections. Transmission is by direct inoculation, inhalation, or ingestion. Risk factors for melioidosis include male sex, diabetes mellitus, alcohol abuse, and immunosuppression. The organism is well adapted to intracellular survival, with numerous virulence mechanisms. Immunity likely requires innate and adaptive responses. The principles of management of this condition are drainage and debridement of infected material and appropriate antimicrobial therapy. Global mortality rates vary between 9% and 70%. Research into vaccine development is ongoing.

Burkholderia pseudomallei invades the olfactory nerve and bulb after epithelial injury in mice and causes the formation of multinucleated giant glial cells in vitro

The infectious disease melioidosis is caused by the bacterium Burkholderia pseudomallei. Melioidosis is characterised by high mortality and morbidity and can involve the central nervous system (CNS). We have previously discovered that B. pseudomallei can infect the CNS via the olfactory and trigeminal nerves in mice. We have shown that the nerve path is dependent on mouse strain, with outbred mice showing resistance to olfactory nerve infection. Damage to the nasal epithelium by environmental factors is common, and we hypothesised that injury to the olfactory epithelium may increase the vulnerability of the olfactory nerve to microbial insult. We therefore investigated this, using outbred mice that were intranasally inoculated with B. pseudomallei, with or without methimazole-induced injury to the olfactory neuroepithelium. Methimazole-mediated injury resulted in increased B. pseudomallei invasion of the olfactory epithelium, and only in pre-injured animals were bacteria found in the olfactory nerve and bulb. In vitro assays demonstrated that B. pseudomallei readily infected glial cells isolated from the olfactory and trigeminal nerves (olfactory ensheathing cells and trigeminal Schwann cells, respectively). Bacteria were degraded by some cells but persisted in other cells, which led to the formation of multinucleated giant cells (MNGCs), with olfactory ensheathing cells less likely to form MNGCs than Schwann cells. Double Cap mutant bacteria, lacking the protein BimA, did not form MNGCs. These data suggest that injuries to the olfactory epithelium expose the primary olfactory nervous system to bacterial invasion, which can then result in CNS infection with potential pathogenic consequences for the glial cells.

Infections of the central nervous system (CNS), though uncommon, are associated with severe morbidity and mortality. Burkholderia pseudomallei, the causative agent of melioidosis, can infect the CNS. We have shown that B. pseudomallei can enter the CNS via peripheral nerves extending between the nasal cavity and the brain (bypassing the blood-brain/blood-cerebrospinal fluid barriers). In the current study, we show that prior injury to the olfactory epithelium can increase B. pseudomallei invasion of the olfactory nerve and bulb, highlighting a novel risk factor for CNS infections. We also demonstrate the ability of peripheral nerve glia to internalise B. pseudomallei, resulting in the formation of multinucleated giant cells (MNGCs), dependent on the bacterial protein BimA. These findings provide important new insights into the pathogenesis of B. pseudomallei.

Cranial Melioidosis Presenting as Osteomyelitis and/or Extra-Axial Abscess: Literature Review

BACKGROUND

Central nervous system (CNS) melioidosis is rare. Clinical presentations depend on the region of endemicity. Despite treatment, neurologic disease has relatively high mortality rates. Less than 80 cases of CNS involvement have been reported.

METHODS

A literature review was performed by searching online databases for melioidosis presenting as osteomyelitis or scalp/extra-axial abscess (OSEAA). In addition, 3 similar cases managed at my institute have been presented.

RESULTS

Including this report of 3 cases, 20 additional cases have been reported. Of these, 12 cases (60%) were from India. The mean age of patients was 45.5 years (range, 29-74 years), and none were in the pediatric age group. Patients in the fifth to sixth decades were most frequently affected. The male to female ratio was 5.3:1. Eleven patients had predisposing factors. Fever, headache, and scalp swelling were the most common features. Five cases had history of previous melioid infection. Seven cases had systemic disease. Debridement was performed in 11 cases. The average intensive phase treatment duration was 4.6 weeks (range, 2-8 weeks) and 5.5 months (range, 3-12 months) for the maintenance phase. Mean follow-up duration was 13.5 months (range, 2 weeks-40 months). Two deaths (10%) were reported, and 1 case of residual frontal abscess had relapse.

CONCLUSIONS

Cranial melioidosis presenting as OSEAA is associated with good outcome, in contrast with other neurologic presentations. Intensive phase for at least 2-3 weeks followed by maintenance phase for 3-6 months is the standard treatment, similar to other melioid presentations. A high degree of suspicion and accurate identification of the organism is crucial. Patients need to be monitored for recurrences, both clinically and radiologically.

Central nervous system melioidosis: A systematic review of individual participant data of case reports and case series

BACKGROUND

Central nervous system (CNS) melioidosis is rare. However, delayed diagnosis and treatment could lead to fatality. To identify knowledge of CNS melioidosis, we systematically review case reports and case series.

METHODOLOGY/PRINCIPAL FINDINGS

We searched through PubMed, Web of Science and Thai-Journal Citation Index databases as well as Google Scholar with the last date on July 10, 2018. The diagnosis of CNS melioidosis had to be confirmed with culture, serology or polymerase chain reaction. We excluded the animal cases and the studies that the clinical data were not available. We identified 1170 relevant studies, while 70 studies with a total of 120 patients were analyzed. Ninety-three percent of patients were reported from the endemic area of melioidosis. Median age was 40 years (IQR 18-53), and 70% were men. A total of 60% had one or more risk factors for melioidosis. The median duration from clinical onset to diagnosis was ten days (IQR 5-25). Fever (82%), headache (54%), unilateral weakness (57%) and cranial nerve deficits (52%) are among the prominent presentation. Most patient (67%) had at least one extraneurological organ involvement. The CSF profile mostly showed mononuclear pleocytosis (64%), high protein (93%) and normal glucose (66%). The rim-enhancing pattern (78%) is the most frequent neuroimaging finding in encephalomyelitis and brain abscess patients. Both brainstem (34%) and frontal lobe (34%) are the most affected locations. Mortality rate was 20%.

CONCLUSIONS/SIGNIFICANCE

This study is the most extensive systematic review of case reports and case series of CNS melioidosis in all age groups. However, the results should be cautiously interpreted due to the missing data issue. The propensity of brainstem involvement which correlates with prominent cranial nerve deficits is the characteristic of CNS melioidosis especially encephalomyelitis type. The presenting features of fever and neurological deficits (especially cranial nerve palsies) along with the mononuclear CSF pleocytosis in a patient who lives in the endemic area and also has the risk factor for melioidosis should raise the CNS melioidosis as the differential diagnosis.

The Tunnel Sign Revisited: A Novel Observation of Cerebral Melioidosis Mimicking Sparganosis

The tunnel sign has been described as a specific feature of cerebral sparganosis. We present a case of a 55-year-old gentleman found to have cerebral melioidosis and with initial imaging mimicking the appearance of sparganosis. This suggests that the tunnel sign in brain abscesses may be specific for infection by Burkholderia Pseudomallei, Spirometra Mansoni or Listeria Monocytogenes.

Melioidosis: An Australian Perspective

Burkholderia pseudomallei is endemic in northern Australia, with cases of melioidosis most commonly occurring during the wet season in individuals with diabetes, hazardous alcohol use, and chronic kidney disease. Pneumonia is the most common presentation and the majority of patients are bacteraemic—however, infection may involve almost any organ, with the skin and soft tissues, genitourinary system, visceral organs, and bone and joints affected most commonly. Central nervous system involvement is rarer, but has a high attributable mortality. Increased awareness of the disease amongst healthcare providers, ready access to appropriate antibiotic therapy and high-quality intensive care services has resulted in a sharp decline in the case fatality rate over the last 20 years. Further improvement in clinical outcomes will require a greater understanding of the disease′s pathophysiology, its optimal management, and more effective strategies for its prevention.

Central nervous system melioidosis in the pediatric age group: review

PURPOSE

Melioidosis is a potentially fatal infectious disease caused by Burkholderia pseudomallei. Neurologic involvement in pediatric age group is very rare, and only a handful of cases have been reported in literature. We sought to provide a systematic review of pediatric neurologic melioidosis.

METHODS

Literature review was performed to analyze reported cases of pediatric neurologic melioidosis (≤16 years) by searching online database (PubMed/MEDLINE).

RESULTS

Twenty-seven cases were analyzed. Mean age was 6.7 years (range 2 days-14 years) and around 50% were older children (>5 years). Cranial nerve palsies and fever were most common presenting features. Major manifestations were meningoencephalitis in 16 (59%) and cerebral abscesses in eight (29%) cases. Abscesses were mostly located in parietal lobe. Among older children, abscesses were common than meningeal disease, while being converse for neonates. Mean follow-up duration was 11.5 months. Ten cases showed good to excellent outcome, while eight cases had fair (incomplete recovery) outcomes. The overall mortality rate was 18.5% (5/27) and tends to decrease with age. Among the five deaths, 4 (80%) had septicemia or pneumonia.

CONCLUSIONS

Pediatric neurologic melioidosis is very rare. Meningoencephalitis is the most common presentation. Mortality is the highest in neonates. Ceftazidime appears to be the drug of choice in intensive phase, although the best drug in maintenance phase cannot be commented upon, especially in very young children.

Neuromelioidosis: a series of seven cases in Hainan province, China

Melioidosis, which is caused by Burkholderia pseudomallei, is predominately a disease of tropical climates and is especially widespread in south-east Asia and northern Australia. Melioidosis affecting the central nervous system has a low incidence but a high mortality. We present seven cases of neuromelioidosis and analyze the disease characteristics and imaging features. Typical clinical features of this disease included high fever and headache. Five patients had an irregular fever with a temperature ≥ 39℃. Peripheral blood leukocytes and the neutrophil ratio were raised in all patients. On computed tomography and magnetic resonance imaging the disease mainly manifested as intracerebral single or multiple nodules, as well as ring and flake-like enhancements with rapid lesion progression. This study demonstrated the importance of imaging examination in the clinical evaluation and diagnosis of neuromelioidosis.

Serial magnetic resonance imaging findings of intracerebral spread of listeria utilising subcortical U-fibres and the extreme capsule

We present a case of Listeria monocytogenes cerebral abscess with axonal spread via the subcortical U-fibres and extreme capsule on magnetic resonance imaging, with follow-up studies demonstrating serial reduction in oedema and enhancement pattern of the white-matter fibre tracts following antimicrobial treatment. We discuss the microbiological mechanism of bacterial mobility to account for these unique imaging features. Recognition of this distinct pattern of spread of L. monocytogenes cerebral abscess may aid in diagnosis and enable early microbiological culture and treatment.