Related Experiment Video
Updated: Jun 14, 2026
10:21
In Vivo Imaging Systems (IVIS) Detection of a Neuro-Invasive Encephalitic Virus
Published on: December 2, 2012
Beyond the borders-coma as a complication of imported Japanese encephalitis: a case report
Gio Gemelga1, Vishwajit Tuchscherer2, Jessie Wang2
1St. Joseph's Medical Center, 1800 N California St., Stockton, CA, 95204, USA. giogemelga@yahoo.com.
Journal of Medical Case Reports
|June 13, 2026
Summary
Japanese encephalitis (JE) is a rare but severe mosquito-borne illness. Immunocompromised travelers returning from endemic areas face diagnostic challenges and poor outcomes, underscoring the need for vigilance and vaccination.
Area of Science:
- Neurology
- Infectious Diseases
- Public Health
Background:
- Japanese encephalitis (JE) is a significant mosquito-borne flavivirus infection prevalent in Asia and the Western Pacific.
- While most JE infections are asymptomatic, a small percentage develop acute encephalitis with high fatality and sequelae rates.
- Risk for travelers, especially immunocompromised individuals, increases with exposure in endemic regions and lack of vaccination.
Purpose of the Study:
- To highlight the diagnostic difficulties of acute encephalopathy in immunocompromised travelers.
- To present a case of severe Japanese encephalitis in an immunocompromised patient with atypical neuroimaging findings.
- To emphasize the importance of considering imported JE in at-risk travelers.
Main Methods:
- A case report of a 70-year-old immunocompromised male with multiple myeloma presenting with confusion and weakness after travel to Laos.
- Clinical evaluation included neuroimaging (CT, MRI), cerebrospinal fluid analysis, and serologic testing for JEV.
- Management involved supportive care, empiric antibiotics, and multidisciplinary discussions leading to comfort care.
Main Results:
- The patient presented with fever, encephalopathy, and rigidity, with MRI showing bilateral frontal and insular cortical hyperintensities.
- Cerebrospinal fluid analysis revealed elevated protein without pleocytosis, and infectious workup was initially negative.
- Serology confirmed recent JEV infection, but the patient's condition rapidly deteriorated, leading to death.
Conclusions:
- Immunocompromised status, particularly myeloma-related immune dysfunction, likely impaired viral clearance and led to rapid JE progression.
- Atypical neuroimaging findings (frontal/insular involvement) and potential co-infection with neurocysticercosis complicated the presentation and prognosis.
- Holistic patient evaluation, including detailed travel history and recognition of atypical presentations, is crucial for diagnosing imported JE in immunocompromised travelers.
Related Concept Videos
01:19Encephalitis l: Introduction
Encephalitis is inflammation of the brain parenchyma, most often due to infections or autoimmune processes. It presents with neuropsychiatric features such as fever, altered mental status, behavioral changes, cognitive dysfunction, seizures, focal deficits, and sometimes autonomic instability. In some cases, the meninges are also involved, resulting in meningoencephalitis.Infectious CausesInfectious encephalitis is most commonly viral but can also result from bacterial, fungal, or parasitic...
01:26Encephalitis ll: Pathophysiology
Encephalitis is inflammation of the brain parenchyma caused by direct viral invasion or immune-mediated mechanisms triggered by infections or tumors. Both processes lead to neuronal injury, disrupted neurotransmission, and diverse neurological symptoms, often with overlapping clinical and pathological features.Autoimmune EncephalitisIn autoimmune encephalitis, antibodies target neuronal antigens on cell surfaces, synapses, or within neurons. A key example is anti-NMDAR encephalitis, which can...
01:25Arboviral Encephalitis
Arboviral encephalitis refers to brain inflammation caused by arthropod-borne viruses, particularly those transmitted through mosquito vectors. Among these, West Nile virus (WNV), a member of the Flaviviridae family, is a significant public health concern. WNV is an enveloped, positive-sense, single-stranded RNA virus. Human infection typically begins when an infected mosquito introduces the virus into the dermis during feeding. The primary transmission cycle involves birds as amplifying hosts...
01:26Brain Abscess l: Introduction
A brain abscess is a focal, intracerebral infection characterized by a localized collection of pus within the brain parenchyma, resulting from microbial invasion and the body’s inflammatory response. It progresses through stages: early and late cerebritis, followed by early and late capsule formation, reflecting tissue destruction, immune response, and eventual encapsulation.Etiology and PathogenesisCausative organisms vary with source and host factors, often involving polymicrobial infections,...
01:22Bacterial Meningitis I: Introduction
Bacterial meningitis is a severe, life-threatening inflammation of the meninges, particularly the pia mater and arachnoid mater, affecting the subarachnoid space, ventricles, and cerebrospinal fluid (CSF). If untreated, it can lead to significant neurological complications or death.Causative AgentsCommon pathogens vary with age and immune status. In adults, major organisms include Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. Streptococcus agalactiae (group B...
01:26Rocky Mountain Spotted Fever
Rocky Mountain Spotted Fever (RMSF) is a severe tick-borne illness caused by Rickettsia rickettsii, a Gram-negative, coccobacillary bacterium. This pathogen is an obligate intracellular parasite, requiring a host cell for replication. Transmission occurs through the bite of an infected tick. In the United States, the most important vectors are Dermacentor variabilis (American dog tick) and Dermacentor andersoni (Rocky Mountain wood tick), though other tick species may also serve as vectors.