An atypical presentation of meliodosis – A case report

Abstract

Meliodosis is bacterial infection caused by gram negative bacillus called Burkholderia pseudomallei. It is endemic in tropical and subtropical regions of world. Clinical manifestations can vary which include pneumonia, abscess, joint infection, non-healing ulcer and sometimes severe sepsis requiring ICU admission. This article narrates our encounter with a neuromeliodosis which presents as acute transverse myelitis.

Introduction

The infective pathogen Burkholderia pseudomallei was first recognized in 1911 in rhinosphere and ground water in tropical and subtropical regions. This can cause infections in animals and humans⁽¹⁾. Entry of organisms into human occur through broken skin or inhalational route. Neuromelioidosis is a rare but severe manifestation of melioidosis caused by Burkholderia pseudomallei, a gram-negative environmental organism endemic to tropical regions such as Southeast Asia and India. Central nervous system (CNS) involvement occurs in approximately 1–5% of cases but carries high mortality and neurological sequelae.

Case presentation

A 57 years old female presented to OPD with history of difficulty in using bilateral upper limbs for past 7 days. MRI brain was normal. MRI cervical spine revealed long segment T2w hyperintensity involving cervical spinal cord from C2 to D1- likely inflammatory, longitudinal transverse myelitis. CSF analysis showed inflammatory pattern with lymphocyte predominant leucocytosis with elevated protein. She was started on pulse steroids Inj. Methylpred 500 mg IV BD. Her weakness  worsened  during  hospital  stay.  She  was  intubated  in  view  of respiratory muscle weakness. Repeat MRI cervical spine showed progression of disease with involvement of medulla and midbrain superiorly and involvement of dorsal spine inferiorly. She was planned for IV immunoglobulin. But due to logistic issues patient attenders opted for discharge against medical advice. CSF cultures send finally grew Burkholderia pseudomallei, which grew after the patient discharge. Hence it was neuromeliodosis which presented as acute transverse myelitis, a rare presentation.

Discussion

Epidemiology

Neuromelioidosis is an uncommon but life-threatening manifestation of infection caused by Burkholderia pseudomallei, an environmental gram-negative bacillus found in soil and surface water. The disease is endemic in regions such as Southeast Asia and northern Australia, with increasing recognition in India, particularly in coastal and tropical zones. Central nervous system (CNS) involvement occurs in a small proportion of melioidosis cases (around 1–5%), but it is associated with disproportionately high mortality and morbidity(2). ICU admission is often required due to severe neurological impairment, respiratory compromise, or septic shock.

Pathophysiology

The organism gains entry primarily through:

• Skin inoculation
• Inhalation
• Ingestion

Following entry, bacteremia can occur, leading to hematogenous spread to the CNS. Two major mechanisms are described(3):

1. Hematogenous dissemination
   • Leads to multiple microabscesses in the brain
   • Common in septic patients
2. Neural spread
   • Particularly via cranial nerves (e.g., olfactory, trigeminal pathways)
   • Explains predilection for brainstem involvement Common predisposing conditions include:
   • Diabetes mellitus (most important)
   • Chronic kidney disease
   • Alcohol use disorder
   • Chronic lung disease
   • Immunosuppression

However, neuromelioidosis can also occur in immunocompetent individuals, especially following heavy environmental exposure.

Clinical Spectrum in ICU

Neuromelioidosis presents with a wide range of neurological and systemic manifestations:

Neurological Features(4)

• Altered sensorium (most common ICU presentation)
• Focal neurological deficits (hemiparesis, cranial nerve palsies)
• Brainstem syndromes (highly suggestive)
• Seizures
• Acute flaccid paralysis (spinal involvement) Systemic Features
• Fever with sepsis
• Pneumonia (common co-manifestation)
• Septic shock
• Multiorgan dysfunction

Radiological Characteristics

MRI Findings(5)

• Multiple small abscesses (ring-enhancing lesions)
• White matter tract involvement
• Brainstem predilection
• Diffusion restriction (abscesses)
• Spinal cord lesions   (longitudinally extensive    myelitis-like picture)

Diagnostic Challenges

Neuromelioidosis is frequently misdiagnosed due to its resemblance to other CNS infections:

Common Differentials(6)

• Tuberculous meningitis / tuberculoma
• Pyogenic brain abscess
• Viral encephalitis
• Fungal infections

Microbiological Diagnosis

• Gold standard: culture of pseudomallei from blood, CSF or any abscess material(7).

Challenges:

• Slow growth
• Misidentification in routine labs

CSF findings:

• Mild pleocytosis
• Elevated protein
• Normal or mildly low glucose

Management

Early initiation of optimal antimicrobial therapy is key, which along with effective critical care management of sepsis will decrease the mortality to 10%⁽⁸⁾. Burkholderia pseudomallei is mostly susceptible to β-lactum antibiotics, doxycycline, chloramphenicol and co-trimoxazole. They are resistant to penicillins, first and second generation cephalosporins, tobramycin, macrolides and polymyxins. Antibiotic therapy is divided into intensive phase and eradication phase.

Intensive phase

Intensive phase includes the use of IV Ceftazidime 2gm IV 6^th hourly or IV Meropenam 1gm IV 8^th hourly for 10-14 days⁽⁹⁾. Dose of meropenam can increased to 2gm IV 8^th hourly for neuromelioidosis. Therapeutic response can be slow such that resolution of fever can take upto 9 days. Duration of intensive phase can be prolonged to 4-6 weeks in case of deep seated abscess or osteomyelitis.

Eradication phase

Eradication phase starts from the end of intensive phase for a duration of 3 month. It involves the use of co-trimoxazole with careful monitoring of adverse effects of co-trimoxazole. Occurance of adverse effects needs dose modification or switch to second line drugs which include oral doxycline or amoxy-clav⁽¹¹⁾. Longer eradication phase of 6 months may be needed in neuromelioidosis and osteomyelitis.

Surgical management

Surgical drainage of abscess is usually needed in case of single large abscess of muscle, liver or prostate. Repeated drainage and washouts may be needed in case of septic arthiritis. Mycotic aneurysms will require urgent surgery with replacement of prosthetic grafts. In such case, life long eradication therapy will be needed.

Prognosis

Neuromelioidosis carries a guarded prognosis(10):

• Mortality: ~20–30% (higher in ICU settings)
• Poor neurological recovery common
• Long-term sequelae:
• Motor deficits
• Cranial nerve palsies
• Cognitive impairment

Poor Prognostic Factors

• Delayed diagnosis
• Brainstem involvement
• Septic shock
• Diabetes with poor glycemic control
• Inadequate duration of therapy

Conclusion

Melioidosis is serious infection caused by gram negative bacilli, more common in patients with diabetes mellitus or on any immunosupperasants. It has wide range of organ involvement. No vaccine is currently available against melioidosis. Adherence to therapy is the key.

Referances

1. Dimitriou NG, et Case report: Neuromelioidosis in Europe. Front Neurol. 2022.
2. Pareek M, et Neuromelioidosis in Rajasthan. IDCases. 2025.
3. Pandey V, et Spinal meliodosis presenting as myelitis.
4. Isolated spinal neuromelioidosis PubMed. 2021.
5. Melioidosis ICU case PMC. 2023.
6. Saravu K, et Neuromeliodosis case series from India.
7. Huang L, et B. pseudomallei infection case. Medicine. 2018.
8. Cheng AC, Currie Melioidosis review. Clin Microbiol Rev.
9. Limmathurotsakul D, et Global burden of melioidosis. Lancet Infect Dis.

Currie BJ. Neurological melioidosis review. Clin Infect Dis.

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