An 8-year-old girl presented with fibromuscular dysplasia of the intracranial vessels manifesting as ischemic stroke. Neuroimaging showed infarction of the right putamen and ipsilateral frontal white matter. Angiography revealed "string of beads" sign involving the terminal portion of the right internal carotid artery and the horizontal segment of the ipsilateral middle cerebral artery. She was treated conservatively. Magnetic resonance angiography at 2 months post ictus showed similar findings in the middle cerebral artery but improvement of the stenosis of the internal carotid artery. Her neurological deficits had almost resolved. Fibromuscular dysplasia should be part of the differential diagnosis of ischemia in children.
Pediatric movement disorders are still a diagnostic challenge, as many patients remain without a (genetic) diagnosis. Magnetic resonance imaging (MRI) pattern recognition can lead to the diagnosis. MEGDEL syndrome (3-MethylGlutaconic aciduria, Deafness, Encephalopathy, Leigh-like syndrome MIM #614739) is a clinically and biochemically highly distinctive dystonia deafness syndrome accompanied by 3-methylglutaconic aciduria, severe developmental delay, and progressive spasticity. Mutations are found in SERAC1, encoding a phosphatidylglycerol remodeling enzyme essential for both mitochondrial function and intracellular cholesterol trafficking. Based on the homogenous phenotype, we hypothesized an accordingly characteristic MRI pattern. A total of 43 complete MRI studies of 30 patients were systematically reevaluated. All patients presented a distinctive brain MRI pattern with five characteristic disease stages affecting the basal ganglia, especially the putamen. In stage 1, T2 signal changes of the pallidum are present. In stage 2, swelling of the putamen and caudate nucleus is seen. The dorsal putamen contains an "eye" that shows no signal alteration and (thus) seems to be spared during this stage of the disease. It later increases, reflecting progressive putaminal involvement. This "eye" was found in all patients with MEGDEL syndrome during a specific age range, and has not been reported in other disorders, making it pathognomonic for MEDGEL and allowing diagnosis based on MRI findings.
Acute necrotizing encephalopathy of childhood (ANEC) is a rare condition which is important for clinicians to recognize as it has a high mortality rate and can result in significant neurological morbidities. It presents as acute encephalopathy with radiological findings of symmetrical brain lesions in bilateral thalami, putamen, brain stem teg- mentum, internal capsule, periventricular white matter and cerebellar medulla. Intravenous methylprednisolone is the mainstay of treatment. Immunoglobulin therapy and therapeutic hypothermia may be used as adjunctive therapy in cases with severe clinical and neuroradiological presentation. We present a case of severe ANEC and discuss the clinical manifestations, neuroimaging and management options.
We have developed and characterised a mouse model of Japanese encephalitis virus (JEV) infection via
footpad inoculation in order to better mimic viral transmission by mosquito bites. Two-week-old and
5-week-old mice consistently developed signs of infection such as ruffled fur, weight loss, hunchback
posture, tremors, mask-like facies and occasionally, hindlimb paralysis at 4 days post infection (dpi)
and 11-13 dpi, respectively. Most of the animals died within 24 to 48 hours following the onset of signs
of infection, with mortalities of 100% and 33.3% in 2-week-old and 5-week-old mice, respectively.
Mild meningitis and variable parenchymal inflammation with formation of microglial nodules, focal
necrosis and neuronophagia, and perivascular cuffing by inflammatory cells were observed in the
caudate nucleus, putamen, thalamus, cerebral cortex, brainstem, and spinal cord. Viral antigens/RNA
were demonstrated by immunohistochemisty and in situ hybridization, respectively, in most of these
areas as well as in the hippocampus and cerebellum, albeit more focally. The pathological findings in
this mouse model were generally similar to human Japanese encephalitis (JE) and other established JE
models but perhaps, compared to other JEV mouse models, it demonstrates lethal encephalitic infection
more consistently. We believe that our mouse model should be useful to study the pathogenesis of JE,
and for testing anti-viral drugs and vaccines