Cerebellar peduncle damage in Langerhans cell histiocytosis-associated neurodegenerative disease revealed by diffusion tensor imaging

PURPOSE

To confirm the hypothesis that brain white matter damage is involved in the pathogenesis and disease progression of Langerhans cell histiocytosis (LCH)-associated neurodegenerative disease (ND), we aimed to analyze pediatric patients with LCH using diffusion tensor imaging (DTI).

METHODS

We enrolled 33 patients with LCH and obtained 33 DTI datasets. Using DTI-based tractography, fractional anisotropy (FA), apparent diffusion coefficient (ADC), axial diffusivity (AD), and radial diffusivity (RD) were measured in the cerebral and cerebellar white matter tracts. The participants were divided into three groups-non-ND, ND without clinical symptoms (r-ND), and ND with clinical symptoms (c-ND)-according to their clinical status during the examination with DTI. We compared the DTI parameters in white matter tracts were compared among the three groups.

RESULTS

In the order of non-ND, r-ND, and c-ND groups, the FA in superior cerebellar peduncle (SCP) and middle cerebellar peduncle (MCP) significantly decreased, the ADC, AD, and RD of MCP, and the RD of SCP were significantly elevated (FA-SCP; p < 0.001, FA-MCP; p = 0.026, ADC-MCP; p < 0.001, AD-MCP; p = 0.002, RD-MCP; p = 0.003, and RD-SCP; p = 0.018). Furthermore, in the simple linear regression analysis, the FA, ADC, AD, and RD values in the MCP and the FA value in the SCP were significantly influenced by the presence of neurological symptoms and ND findings on MRI (all p < 0.001).

CONCLUSION

In LCH-ND, we identified microstructural damage in the SCP and MCP. DTI parameters in these tracts may help monitor LCH-ND; therefore, future studies are required to validate these results in a large cohort.

The cause of death in bacterial meningitis

Background

Death from bacterial meningitis is rarely attributed to the actual event causing death.

The present study therefore categorized and characterized the cause and time of death due to bacterial meningitis.

Methods

In a cohort of patients > 15 years of age with community acquired bacterial meningitis the medical records were reviewed, and a clinical cause of death categorized into six main categories: 1) CNS complications, 2) Systemic complications, 3) Combination of systemic and CNS complications, 4) Sudden death, 5) Withdrawal of care, or 6) Unknown.

Results

We identified 358 patients of which 84 (23%) died in-hospital. Causes of death were ascribed to CNS complications in 43%, Systemic complications in 39%, Combined CNS and systemic complications in 4%, Sudden death in 7% and withdrawal of care in 5%. Brain herniation, circulatory failure, intractable seizures and other brain injury were the most common specific causes of death within 14 days from admission (55%).

Conclusion

Fatal complications due to the primary infection – meningitis - is most common within 14 days of admission. The diversity of complications causing death in meningitis suggest that determining the clinical cause of death is essential to the evaluation of novel treatment strategies.

Central Nervous System Complications after Allogeneic Hematopoietic Stem Cell Transplantation in Children

Central nervous system complications (CNSCs) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) are common and may be a significant source of morbidity and mortality. We performed a retrospective study of 153 pediatric patients who underwent allo-HSCT to determine CNSC type, incidence, and impact on survival. A total of 34 patients (22.2%) developed CNSCs. The cumulative incidence of CNSCs at 100 days and 3 years was 18.30 and 22.73%, respectively. The most common CNSC was calcineurin inhibitor (CNI)-associated neurotoxicity (50.0%). Risk factors for CNSCs were the time from diagnosis to HSCT ≥4.8 months (p = 0.032) and the development of acute graft-versus-host disease (aGVHD) grade III-IV (p = 0.002). CNSCs after allo-HSCT negatively impacted overall survival (hazard ratio [HR] 1.97, p = 0.043) and nonrelapse mortality (HR 4.84, p < 0.001). In conclusion, CNSCs after allo-HSCT are associated with poor outcomes; patients with severe aGVHD and/or late transplantation should be given more attention.