Neurology India
menu-bar5 Open access journal indexed with Index Medicus
  Users online: 2597  
 Home | Login 
About Editorial board Articlesmenu-bullet NSI Publicationsmenu-bullet Search Instructions Online Submission Subscribe Videos Etcetera Contact
  Navigate Here 
 Resource Links
  »  Similar in PUBMED
 »  Search Pubmed for
 »  Search in Google Scholar for
 »Related articles
  »  Article in PDF (1,714 KB)
  »  Citation Manager
  »  Access Statistics
  »  Reader Comments
  »  Email Alert *
  »  Add to My List *
* Registration required (free)  

  In this Article
 »  Abstract
 » Discussion
 »  References
 »  Article Figures
 »  Article Tables

 Article Access Statistics
    PDF Downloaded5    
    Comments [Add]    

Recommend this journal


Table of Contents    
Year : 2022  |  Volume : 70  |  Issue : 2  |  Page : 767-771

Corticospinal Tract Involvement in MRI of Neuromelioidosis: Report of Three Cases with a Review of Clinicoradiological Features

1 Departments of Radio-Diagnosis, Pediatrics, Jawaharlal Institute of Postgraduate Medical Education and Research JIPMER, Pondicherry, India
2 Departments of Medicine, Jawaharlal Institute of Postgraduate Medical Education and Research JIPMER, Pondicherry, India

Date of Submission11-Dec-2020
Date of Decision31-Mar-2021
Date of Acceptance11-Apr-2021
Date of Web Publication3-May-2022

Correspondence Address:
Dr. Krishnan Nagarajan
Professor of Radio-Diagnosis, Jawaharlal Institute of Postgraduate Medical Education and Research JIPMER, Pondicherry
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0028-3886.344622

Rights and Permissions

 » Abstract 

Melioidosis is gram-negative bacterial infection endemic in parts of Australia and Asia with significant morbidity and mortality. It is acquired in wet rainy seasons through occupational and recreational activities. Although central nervous system (CNS) involvement is seen in less than 10%, it can have severe sequelae. MRI (magnetic resonance imaging) findings in reported cases have shown predominant brain stem and frontoparietal involvement. We present three pediatric cases of neuromelioidosis in which corticospinal tract involvement was a characteristic finding.

Keywords: Corticospinal tact involvement, magnetic resonance imaging, neuromelioidosis
Key Message: Corticospinal tract involvement is one of the characteristic features of neuromelioidosis and MRI plays an important role in the early diagnosis as laboratory findings maybe delayed or even negative.

How to cite this article:
Raj JV, Nagarajan K, Ananthanarayanan K, Swaminathan RP, Bammigatti C. Corticospinal Tract Involvement in MRI of Neuromelioidosis: Report of Three Cases with a Review of Clinicoradiological Features. Neurol India 2022;70:767-71

How to cite this URL:
Raj JV, Nagarajan K, Ananthanarayanan K, Swaminathan RP, Bammigatti C. Corticospinal Tract Involvement in MRI of Neuromelioidosis: Report of Three Cases with a Review of Clinicoradiological Features. Neurol India [serial online] 2022 [cited 2022 Jun 27];70:767-71. Available from: https://www.neurologyindia.com/text.asp?2022/70/2/767/344622

Melioidosis is a bacterial infection, affecting humans as well as animals, caused by gram-negative motile rod-shaped bacterium Burkholderia pseudomallei. It is endemic in Northern Australia and Southeast and South Asia (including India and Sri Lanka).[1] In India, it has been mainly reported from the southwestern coast with increased incidence in rainy or monsoon months.[2] Neurological involvement has been reported as 5% to 10% in various studies but may have significant morbidity and mortality.[1],[3],[4],[5],[6],[7],[8], Currie et al.[3] found 12 cases of neurological involvement out of 232 cases of melioidosis (5%) and also first reported the involvement of corticospinal tract on magnetic resonance imaging (MRI). Chadwick et al.[4] reported five cases from Singapore, of whom three presented with poor GCS (Glasgow Coma Scale) scores but responded to antibiotics and surgical drainage and two had residual neurological impairment. They reported sinusitis on imaging and ascribed this as a route of central nervous system (CNS) entry and the associated extracerebral collections seen in these patients. Similar extradural collections were also reported by Muthuswamy et al.[5] in 2006 from Malaysia in three patients (out of 160 patients with melioidosis over 28 years). Another review by the same group from Darwin in Australia[6] reported 14 cases of primary neurological involvement (10 encephalomyelitis, two myelitis, two cerebral abscesses) and another eight cases of secondary neurological involvement in 540 patients of melioidosis. Five out of the 14 with primary involvement also had extraneurological disease, including three with pneumonia. Of the eight with secondary neurologic melioidosis, all were blood culture positive, whereas only 3 of 14 with primary neurologic melioidosis were blood culture positive. Those acquired through inhalation had severe disease and low bacteremic counts. Deuble et al.[7] in their review reported 12 with neurological involvement out of 211 (4%) of which 20% of blood, CSF (cerebrospinal fluid), and sputum/respiratory aspirate were positive and 50% of pleural fluid and brain biopsy were positive. The sensitivity of indirect hemagglutination (IHA) test was 50%. The Darwin group[8] in 2015 updated their review with 45 pediatric patients (5%) out of total 820 melioidosis cases over 24 years. Cutaneous involvement was the most common presentation (60% vs. 13% in adults), with inoculating event in 42% and brain stem encephalitis in three children. But bacteremia was less common in children (16% vs. 59%) compared with adults. Wongwandee and Linasmita[1] recently analyzed 120 cases of reported neurological melioidosis in 70 reports and found fever, headache, and motor and cranial nerve deficits as common presentations. They also found brain stem (34%) and frontoparietal (34%) involvement in neuroimaging (CT [computed tomography] and MRI) with a mortality of 20%.

Case 1

An 8-year-old boy presented with fever and headache since 20 days and one episode of vomiting. He had three episodes of GTCS (generalized tonic–clonic seizure) and deviation of the left eye since 2 weeks with some difficulty in swallowing and regurgitation. He was febrile with neck stiffness. Power was 2/5 in all four limbs with hypertonia. Cranial nerve examination showed left facial palsy, left lateral rectus palsy, and weak gag reflex. Total white cell count was 13,000 (75% neutrophils) with ESR (erythrocyte sedimentation rate) 95 mm/hr. CSF showed 20 lymphocytes and 5 neutrophils (with glucose 68, protein 78, and chloride 119). MRI showed T2/FLAIR (fluid-attenuated inversion recovery) hyperintensities in the brain stem and cerebellar peduncles, more in the pons with swollen appearance. Similar signal changes were noted in bilateral cerebral peduncles, internal capsule, corona radiata, and perirolandic (frontoparietal) regions with a small “ring-enhancing” lesion in the left precentral region. Linear enhancement was noted along the left side pons and middle cerebellar peduncle along trigeminal entry zone with subtle enhancement along the left corticospinal tract. The spinal cord showed T2 hyperintensities in the upper cervical (up to C5) and upper thoracic (T2–T4) levels without enhancement. On MRS (magnetic resonance spectroscopy), the pontine lesion showed elevated choline and reduced NAA (N-acetylaspartate) [Figure 1]. In view of high choline and atypical imaging findings, stereotactic biopsy was attempted, which showed only reactive gliosis. But antibody titers for Burkholderia pseudomallei (by IHA) were very high (1:2560). The child improved on treatment with meropenem. Follow-up MRI showed a significant decrease in intensity and extent of involvement [Figure 2]. He was discharged without residual deficits.
Figure 1: Case 1. FLAIR axial sections (a-e) showing hyperintensities in pons, middle cerebellar peduncles, midbrain, including cerebral peduncles, internal capsules, corona radiata and peri-rolandic regions (left side more than right). Postcontrast T1-weighted axial (f), T2 coronal (g), and T1 coronal sections (h) showing enhancement in left pons along trigeminal nerve root zone and bilateral corticospinal tracts (left > right). T2-weighted spine sagittal sections showing intramedullary signal changes in the upper cervical (i) and thoracic cord (j)

Click here to view
Figure 2: Case 1 follow-up MRI. FLAIR axial (a-c) and T2 coronal (d) sections showing decrease in the signal changes. T2 sagittal section of cervical cord (e) shows resolution of signal changes. Postcontrast T1 axial (f and g) and coronal sections (h) showing reduction in the lesions and enhancement

Click here to view

Case 2

A 11-year-old boy presented with fever with chills and rigors for 8 days and diplopia and vomiting for 2 days. He was also unable to stand or sit without support since 2 days. He was febrile with neck stiffness. Power was 3/5 in the right upper and lower limbs and 4/5 in the left upper and lower limbs. Cranial nerve examination showed diplopia with right eye ptosis, right eye convergent squint, and right facial nerve palsy. He had neutrophilic leucocytosis 30,760 (82% neutrophils). CSF showed 5 pus cells (glucose 74, protein 75, and chloride 141), and the culture was sterile. MRI showed T2/FLAIR hyperintensities in deep cerebellar white matter and middle cerebellar peduncles. Similar to the first case, there was corticospinal tract involvement including cerebral peduncles, internal capsule, corona radiata and perirolandic (frontoparietal) regions mainly on the left side. Spinal cord was swollen with T2 hyperintensities extending from medulla up to the lower thoracic cord.

Prominent tracking of enhancement was noted along the left corticospinal tract, bilateral inferior cerebellar peduncles, and medullary pyramids extending down into the cord [Figure 3]. Neuromelioidosis was strongly suspected, and the patient improved on treatment with meropenem. On follow-up MRI after 2 months of treatment, a significant decrease in the signal changes and enhancement were noted with near-total resolution of cerebellar and cord involvement.
Figure 3: Case 2. FLAIR axial sections (a-e) showing hyperintensities in deep cerebellar hemispheres and adjacent middle cerebellar peduncles, midbrain, including cerebral peduncles, internal capsules, left corona radiata, and perirolandic regions (minimally on right). T2 coronal (f), postcontrast T1-weighted section (g-j) showing involvement of corticospinal tracts (arrows in f-h), inferior cerebellar peduncles (* ini), and pyramids (arrow in j). T2-wighted sagittal section of cervicothoracic spine (k) showing cord swelling with intramedullary signal changes

Click here to view

Case 3

A 15-year-old boy presented with on-and-off fever since 2 months with headache and weakness of the right upper and lower limbs for 2 weeks. He was febrile with neck stiffness. Power was 2/5 in the right upper and lower limbs and 4/5 in the left upper and lower limbs. Total count was 13,230 (80% neutrophils). CSF showed 122 lymphocytes, 58 neutrophils (glucose 66, protein 52, and chloride 123). MRI showed T2/FLAIR hyperintensities in bilateral perirolandic regions, left corona radiata, and bilateral internal capsule, along the corticospinal tracts up to the cerebral peduncles. Minimal signal changes were noted in the posterior pons. Postcontrast study showed linear tracking enhancement of corticospinal tract noted with small ring-enhancing and nodular lesions in left perirolandic region [Figure 4]. Neuromelioidosis was presumed, and the patient improved on treatment with intravenous meropenem and ceftazidime. Follow-up MRI after 6 weeks revealed significant decrease in signal changes and enhancement.
Figure 4: Case 3. FLAIR axial sections (a-e) showing hyperintensities in pons, cerebral peduncles, internal capsules, left corona radiata, and perirolandic regions (left side more than right). T2 coronal (f), postcontrast T1 sections (g-j) showing ring and nodular enhancement with corticospinal tract involvement

Click here to view

 » Discussion Top

There are two ways of CNS entry of melioidosis that have been described – the transneural (olfactory, trigeminal) and hematogenous (“Trojan horse”), but the former is considered more likely.[9],[10] Trigeminal route is supported by the significant brain stem involvement and subsequent extension cranially to cerebral hemispheres or caudally to spinal cord. But hematogenous route might explain the initial involvement of perirolandic (frontoparietal) region in some of these cases because this region is the direct ending of the dominant middle cerebral artery (MCA) supply to the cerebral hemisphere similar to other infections and metastases.

The earliest MRI report of neuromelioidosis was by Tan et al.[11] in 1995. They reported a case of left frontoparietal abscess out of 28 cases of melioidosis with various organ involvements. Padiglione et al.[12] mentioned that the combination of “striking early, extensive, confluent T2 hyperintensity with disproportionately small enhancing lesions” may be characteristic of melioidosis. Bergin et al.[13] reported two cases of left parietooccipital involvement. Hsu et al.[14] reported neuroimaging findings in 10 cases (two children) and showed that corticospinal tract involvement from the perirolandic region through the internal capsule up to the brain stem (medulla) as characteristic feature of neuromelioidosis. Similar tract involvement was also noted along the corpus callosum and cerebellar peduncles. The second patient showed involvement of inferior cerebellar peduncles apart from corticospinal tract involvement. These lesions may have a mass effect and may be mistaken for space-occupying lesions (SOLs) leading to attempts at biopsy.[15] Extension along the white matter tracts was also noted by Peh et al.[16] in their report and called it a “tunnel sign” similar to that seen with listeria involvement of brain.[17] Melioidosis can also mimic tubercular meningitis not only in clinical and imaging features but also histopathologically as incompletely formed granulomas and abscesses.[18],[19] They may be mistaken for tubercular infection as FDG (fluorodeoxyglucose)-avidity in PET (positron emission tomography) studies.[20] The relatively less common involvement of CNS in melioidosis is hypothesized to be due to variant strains or pathogen-specific determinants that are still under active study.[21],[22]

All our three patients presented during the rainy season (October–November) with fever, neck stiffness, limb weakness, and leucocytosis. Two had cranial nerve palsies. MRI showed involvement of corticospinal tracts in all three cases with enhancement and brain stem involvement in two cases. Spinal cord involvement was seen in two cases. The third case had minimal pontine involvement indicating that entry other than the trigeminal route could be a possibility. First case had high antibody titers, but the other two cases were diagnosed mainly based on MRI findings. All three cases showed prompt clinical improvement with intravenous meropenem and ceftazidime. Follow-up MRI done in all three cases showed decrease in the extent of involvement and contrast enhancement. Steroids were not used in these patients, but acute disseminated encephalomyelitis can closely mimic this picture.

Melioidosis continues to evade early diagnosis because it is not easily isolated from clinical specimens and also due to the prevalence of other infections such as tuberculosis. A strong index of clinical suspicion, in an appropriate background of a young patient from an endemic area; particularly in rainy season presenting with fever, meningeal signs, and cranial nerve palsies; and showing characteristic MRI finding of corticospinal tract involvement, is important as these children have a better outcome with early treatment than adults with preexisting comorbidities. Although corticospinal tract involvement may be noted in many other causes [Table 1], it is important to consider the possibility of neuromelioidosis in acute presentation.
Table 1: Corticospinal tract involvement as the main lesion or part of diffuse lesions

Click here to view

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

 » References Top

Wongwandee M, Linasmita P. Central nervous system melioidosis: A systematic review of individual participant data of case reports and case series. PLoS Negl Trop Dis 2019;13:e0007320.  Back to cited text no. 1
Vidyalakshmi K, Shrikala B, Bharathi B, Suchitra U. Melioidosis: An under-diagnosed entity in western coastal India: A clinico-microbiological analysis. Indian J Med Microbiol 2007;25:245-8.  Back to cited text no. 2
[PUBMED]  [Full text]  
Currie BJ, Fisher DA, Howard DM, Burrow JNC. Neurological melioidosis. Acta Tropica 2000;74:145-51.  Back to cited text no. 3
Chadwick DR, Ang B, Sitoh YY, Lee CC. Cerebral melioidosis in Singapore: A review of five cases. Trans R Soc Trop Med Hyg 2002;96:72-6.  Back to cited text no. 4
Muthusamy K, Waran V, Puthucheary SD. Spectra of central nervous system melioidosis. J Clin Neurosci 2007;14:1213-5.  Back to cited text no. 5
Deuble M, Aquilina C, Norton R. Neurologic melioidosis. Am J Trop Med Hyg 2013;89:535-9.  Back to cited text no. 6
Currie BJ, Ward L, Cheng AC. The epidemiology and clinical spectrum of melioidosis: 540 cases from the 20 year darwin prospective study. PLoS Negl Trop Dis 2010;4:e900.  Back to cited text no. 7
McLeod C, Morris PS, Bauert PA, Kilburn CJ, Ward LM, Baird RW, et al. Clinical presentation and medical management of melioidosis in children: A 24-year prospective study in the Northern territory of Australia and review of the literature. Clin Infect Dis 2015;60:21-6.  Back to cited text no. 8
St. John JA, Ekberg JA, Dando SJ, Meedeniya AC, Horton RE, Batzloff M, et al. Burkholderia pseudomallei penetrates the brain via destruction of the olfactory and trigeminal nerves: Implications for the pathogenesis of neurological melioidosis. mBio 2014;5:e00025-14.  Back to cited text no. 9
Liu PJ, Chen YS, Lin HH, Ni WF, Hsieh TH, Chen HT, et al. Induction of mouse melioidosis with meningitis by CD11b+phagocytic cells harboring intracellular B. pseudomallei as a Trojan horse. PLoS Negl Trop Dis 2013;7:e2363.  Back to cited text no. 10
Tan AP, Pui MH, Tan LK. Imaging patterns in melioidosis. Australas Radiol 1995;39:260-4.  Back to cited text no. 11
Padiglione A, Ferris N, Fuller A, Spelman D. Brain abscesses caused by Burkholderia pseudomallei. J Infect 1998;36:335-7.  Back to cited text no. 12
Bergin P, Boyes L, Sage M. Cerebral melioidosis. Australas Radiol 2005;49:79-83.  Back to cited text no. 13
Hsu CC, Singh D, Kwan G, Deuble M, Aquilina C, Korah I, et al. Neuromelioidosis: Craniospinal MRI findings in Burkholderia pseudomallei infection. J Neuroimag 2016;26:75-82.  Back to cited text no. 14
Liang CC, Chen S-Y, Chen T-Y, Chen S-T. Central nervous system melioidosis mimics malignancy: A case report and literature review. World Neurosurg 2016;89:732.e19-23.  Back to cited text no. 15
Peh WM, Hean GG, Clement YH. The tunnel sign revisited: A novel observation of cerebral melioidosis mimicking sparganosis. J Radiol Case Rep 2018;12:1-11.  Back to cited text no. 16
Bojanowski MW, Seizeur R, Effendi K, Bourgouin P, Magro E, Letourneau-Guillon L. Spreading of multiple listeria monocytogenes abscesses via central nervous system fiber tracts: Case report. J Neurosurg 2015;123:1593-9.  Back to cited text no. 17
Vidyalakshmi K, Chakrapani M, Shrikala B, Damodar S, Lipika S, Vishal S. Tuberculosis mimicked by melioidosis. Int J Tuberc Lung Dis 2008;12:1209-15.  Back to cited text no. 18
Stockton JL, Torres AG. Multinucleated giant cell formation as a portal to chronic bacterial infections. Microorganisms 2020;8:1637.  Back to cited text no. 19
Kulkarni P, Shelley S, Elangoven IM, Jaykanth A, Ejaz AP, Rao NS. 18-Fluorine fluorodeoxyglucose positron emission tomography – Computed tomography in the evaluation of the great masquerader melioidosis: A case series. Indian J Nucl Med 2020;35:222-5.  Back to cited text no. 20
  [Full text]  
Morris JL, Fane A, Sarovich DS, Price EP, Rush CM, Govan BL, et al. Increased neurotropic threat from Burkholderia pseudomallei strains with a B. mallei-like variation in the bimA motility gene, Australia. Emerg Infect Dis 2017;23:740-9.  Back to cited text no. 21
Shaw T, Tellapragada C, Kamath A, Kalwaje Eshwara V, Mukhopadhyay C. Implications of environmental and pathogen specific determinants on clinical presentations and disease outcome in melioidosis patients. PLoS Negl Trop Dis 2019;13:e0007312.  Back to cited text no. 22


  [Figure 1], [Figure 2], [Figure 3], [Figure 4]

  [Table 1]


Print this article  Email this article
Online since 20th March '04
Published by Wolters Kluwer - Medknow