Related Experiment Video
Updated: Mar 18, 2026
In Vivo Imaging Systems IVIS Detection of a Neuro-Invasive Encephalitic Virus
Published on: December 2, 2012
[Saint Louis encephalitis: case report]
Carolina Carballo1, Magdalena Cabana2, Francisca Ledezma2
1Servicio de Infectología Infantil, Hospital de Niños Ricardo Gutiérrez, Ciudad Autónoma de Buenos Aires, Argentina. Carolinacarballo1981@gmail.com.
Abstract:
Saint Louis encephalitis is transmitted by Culex mosquitoes. In Argentina sporadic cases are registered. Symptomatic illness is unusual in children. We present a case of meningoencephalitis caused by an uncommon viral infection. The clinical signs and symptoms are unusual for pediatric patients and the bilateral thalamic compromise showed on magnetic resonance has not been described previously. An 8-year-old girl consulted due to fever, behavior disorders and ataxia. Clonus and neck stiffness were detected at physical exam. Cerebrospinal fluid revealed mononuclear leukocytosis; bilateral ischemic compromise was observed in thalamus by magnetic resonance. Saint Louis virus was confirmed by serology: serum and cerebrospinal fluid IgM were positive during the acute phase of the disease and serum IgG was positive four weeks later. Most of the signs and symptoms of the disease were resolved, however mild behavior disorders were observed as acute sequelae up to 45 days after hospital discharge.
Insights
Saint Louis encephalitis, a rare pediatric illness, can cause meningoencephalitis with unusual thalamic brain damage. Early diagnosis and treatment are crucial for recovery and managing potential long-term behavioral changes.
Area of Science:
- Neuroscience
- Virology
- Pediatrics
Background:
- Saint Louis encephalitis (SLE) is a mosquito-borne viral illness primarily affecting adults.
- While sporadic cases occur in Argentina, symptomatic illness in children is uncommon.
- Typical presentations involve fever, headache, and neurological symptoms.
Observation:
- An 8-year-old girl presented with fever, behavioral changes, and ataxia.
- Physical examination revealed clonus and nuchal rigidity.
- Magnetic resonance imaging (MRI) demonstrated bilateral thalamic compromise, an unusual finding.
Findings:
- Cerebrospinal fluid analysis showed mononuclear pleocytosis.
- Serological tests confirmed Saint Louis virus infection with positive IgM and IgG antibodies.
- The patient experienced resolution of most symptoms, with mild behavioral disorders persisting as sequelae.
Implications:
- This case highlights the potential for severe neurological manifestations of SLE in pediatric patients.
- Bilateral thalamic involvement represents a novel MRI finding in Saint Louis encephalitis.
- Understanding these unusual presentations is vital for accurate diagnosis and management of pediatric neurovirological infections.
