Factors influencing the development of infantile traumatic brain injury with a biphasic clinical course and late reduced diffusion.

BACKGROUND: Infantile traumatic brain injury (TBI) with a biphasic clinical course and late reduced diffusion (TBIRD) has been reported as a type of TBI. However, it remains uncertain which pediatric patients with TBI develop TBIRD. METHODS: Patients with TBI who were admitted to our hospital and underwent magnetic resonance imaging (MRI) between December 2006 and October 2022 were included in this study. A diagnosis of TBIRD was made in patients with or suspected TBI, with initial symptoms being convulsions or disturbance of consciousness and late-onset subcortical reduced diffusion, the so-called bright tree appearance. Clinical features, neuroimaging (computed tomography (CT) and MRI) findings, laboratory data, and Tada score were retrospectively compared between TBIRD and non-TBIRD patients. Neurological prognosis was assessed using the Pediatric Cerebral Performance Category scale. RESULTS: Of 21 patients who met the inclusion criteria, a diagnosis of TBIRD was made in 7 patients (median age: 8 months). The factors contributing to TBIRD development were seizures lasting over 30 min as the initial symptom (5/7 in TBIRD vs. 0/14 in non-TBIRD), tracheal intubation during initial treatment (5/7 vs. 0/14), and brain parenchymal lesions on CT (3/7 vs. 0/14), suggesting that severe TBI may progress to TBIRD. The Tada score was more positive in patients with TBIRD (6/7) than in those without (0/14). CONCLUSIONS: It is important to monitor infant patients with severe TBI for the development of TBIRD. The Tada score can be a useful tool for TBIRD prediction.

Unilateral internal carotid artery absence in trisomy 18.

BACKGROUND: Internal carotid artery (ICA) absence (agenesis or aplasia) is a rare congenital anomaly that is usually asymptomatic and found coincidentally. There has been no report showing a specific chromosomal abnormality causes ICA absence. CASE REPORTS: MR angiography in a Japanese male infant with trisomy 18 revealed left ICA absence with the left middle cerebral artery (MCA) and anterior cerebral artery (ACA) supplied from the ipsilateral posterior communicating artery and anterior communicating artery (ACoA), respectively, type A in Lie's classification. Another Japanese male infant with trisomy 18 showed right ICA absence with the right ACA and MCA supplied from the ACoA, that is, type B in Lie's classification. CONCLUSION: There have been no pathological or radiological reports of ICA absence in trisomy 18, however, it may be underestimated because the anomaly usually causes no clinical symptoms. It is necessary to evaluate further patients to clarify whether or not unilateral ICA absence is a characteristic congenital malformation.

Increased cytokines/chemokines and hyponatremia as a possible cause of clinically mild encephalitis/encephalopathy with a reversible splenial lesion associated with acute focal bacterial nephritis.

OBJECTIVE: Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS), the second most common encephalopathy syndrome in Japan, is most often associated with viral infection. Bacterial MERS has been rarely reported but is mostly associated with acute focal bacterial nephritis (AFBN) for an unknown reason. We examined cytokines and chemokines in four MERS patients with AFBN to determine if they play an important role in the pathogenesis. METHODS: We examined the clinical charts and MRI results in four MERS patients with AFBN, and measured 10 cytokines and chemokines in serum and cerebrospinal fluid in the acute phase. These were analyzed using the Mann-Whitney U test, compared with the control group (cases with a non-inflammatory neurological disease). Longitudinal changes in the serum cytokine and chemokine levels were evaluated in two patients. RESULTS: Hyponatremia was observed in all four patients with MERS associated with AFBN (128-134 mEq/L). CSF analysis revealed increased cytokines/chemokines associated with Th1 (CXCL10, TNF-α, IFN-γ), T reg (IL-10), Th17 (IL-6), and neutrophil (IL-8 and CXCL1). In serum, upregulation was observed in those associated with Th1 (CXCL10, TNF-α, IFN-γ), Th17 (IL-6), and inflammasome (IL-1ß). The increased serum cytokines/chemokines in the acute stage normalized within 2 weeks in patients 1 and 2, so examined, in accordance with their clinical improvement. CONCLUSION: Increased cytokines/chemokines and hyponatremia may be factors that explain why AFBN is likely to cause MERS.

Infantile traumatic brain injury with a biphasic clinical course and late reduced diffusion.

Reduced diffusion in the subcortical white matter has been reported in some infants with traumatic brain injury (TBI), including abusive head trauma. However, the pathomechanisms of the lesions and clinical features are uncertain. We herein report two infants with TBI who presented with biphasic clinical courses and late reduced diffusion in the subcortical white matter, and reviewed seven clinically and radiologically similar patients with TBI. Their clinical features (secondary neurological symptoms on days 3 to 6) and radiological findings (normal diffusion on days 1 to 2, followed by reduced diffusion on days 3 to 6) are very similar to those observed in patients with acute encephalopathy with biphasic seizures and late reduced diffusion (AESD). MR spectroscopy in one patient revealed a transient increase of glutamine, which is also observed in AESD, suggesting excitotoxicity as a possible pathomechanism.