Spontaneous intracerebral haemorrhage associated with early-onset cerebral amyloid angiopathy and Alzheimer's disease neuropathological changes five decades after cadaveric dura mater graft

In Vivo Seeding of Amyloid-β Protein and Implications in Modeling Alzheimer's Disease Pathology

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by extracellular plaques containing amyloid β-protein (Aβ) and intracellular neurofibrillary tangles formed by tau. Cerebral Aβ accumulation initiates a noxious cascade that leads to irreversible neuronal degeneration and memory impairment in older adults. Recent advances in Aβ seeding studies offer a promising avenue for exploring the mechanisms underlying amyloid deposition and the complex pathological features of AD. However, the extent to which inoculated Aβ seeds can induce reproducible and reliable pathological manifestations remains unclear due to significant variability across studies. In this review, we will discuss several factors that contribute to the induction or acceleration of amyloid deposition and consequent pathologies. Specifically, we focus on the diversity of host animals, sources and recipe of Aβ seeds, and inoculating strategies. By integrating these key aspects, this review aims to offer a comprehensive perspective on Aβ seeding in AD and provide guidance for modeling AD pathogenesis through the exogenous introduction of Aβ seeds.

Iatrogenic Dementia: Providing Insight into Transmissible Subtype of Alzheimer's Disease, Creutzfeldt-Jakob Disease and Cerebral Amyloid Angiopathy

Within the phenotypic spectrum of Alzheimer's disease (AD), Creutzfeldt-Jakob disease (CJD) and cerebral amyloid angiopathy (CAA), dementia that is attributed to iatrogenic transmission has increasingly gained scientific attention recently. Newly recognized, this treatment-induced form of dementia may result from exposure to certain medical or surgical procedures. The present review aims to explore the distinct features of acquired dementia encompassing a history of potential exposure and relatively early age of onset, highlighting transmission potential with a rather prion-like pattern. Having reviewed all available relevant literature, dementia of iatrogenic etiology represents a new disease entity that requires an individualized investigation process and poses a great clinical challenge as far as patients with AD, CJD and CAA are concerned. Understanding the underlying pathophysiology of these rare forms of dementia may significantly enhance awareness within clinical field of neurodegenerative diseases and facilitate their prompt management.

The probability of cerebral amyloid angiopathy according to the Simplified Edinburgh CT criteria in a large, unselected lobar intracerebral hemorrhage population

PURPOSE

Early identification of the underlying cause of intracerebral hemorrhage (ICH) is important for treatment and prognosis. This study aims to investigate the association of hematoma volume and other clinical parameters on the distribution of cerebral amyloid angiopathy (CAA) probability according to the simplified Edinburgh CT criteria in a large, unselected intracerebral hemorrhage (ICH) population.

METHOD

Patients with spontaneous ICH residing in Skane county registered with clinical data in the Swedish Stroke Register 2016-2020 were included. Radiological parameters were evaluated using baseline non-contrast CT (NCCT) for categorization according to the simplified Edinburgh CT criteria by the presence of subarachnoid hemorrhage (SAH) and fingerlike-projections (FLP). Multivariable logistic regression analysis was used to determine factors associated with an increased (intermediate/high) CAA probability.

RESULTS

Of 666 patients with lobar ICH, 190 (29%) had high, 92 (14%) had intermediate, and 384 (58%) had low CAA probability. Patients with increased CAA probability presented more often with decreased level of consciousness, larger hematoma volumes, and higher 90-day mortality. Baseline hematoma volume [10-30 ml (OR = 4.03;95%CI: 2.26-7.19); 30-80 ml (OR = 12.00;95%CI:7.26-22.53); >80 ml (OR = 30.00;95%CI:15.94-59.09)], female sex (OR = 1.58;95%CI:1.08-2.32) and age (OR = 1.04;95%CI:1.02-1.06) were associated with an increased odds of having an increased CAA probability.

CONCLUSION

We identified a strong association between baseline hematoma volume and an increased probability of CAA in lobar ICH patients on NCCT, indicating that large hematoma volumes alone may contribute to the occurrence of FLP and SAH, and act as a confounder for the simplified Edinburgh CT criteria. Validation against MRI is warranted.

A Case of Multiple Intracerebral Hemorrhages Due to Early-Onset Cerebral Amyloid Angiopathy With Alzheimer's Disease: Neuropathological Changes Three Decades After Childhood Neurosurgery

Cerebral amyloid angiopathy (CAA) is a disease in which amyloid beta (Aβ) is deposited in blood vessels and meninges in the brain. Cerebral amyloid angiopathy typically occurs in the elderly but is also known to occur in younger patients with a history of childhood head trauma or dura graft following neurosurgical procedures. The patient was a 39-year-old female who had undergone neurosurgery for an arachnoid cyst in the right temporal lobe at the age of two years. Severe headache, dizziness, and right leg weakness developed abruptly. The Aβ42/40 ratio had decreased in cerebrospinal fluid. Brain MRI showed multiple cerebral hemorrhages. Considering CAA, a brain biopsy was performed. Pathological examination showed severe CAA in many leptomeningeal and cortical vessels. We reported early-onset CAA after neurosurgery in childhood. In young patients with cerebral hemorrhages, it is necessary to consider early-onset CAA following childhood head trauma or neurosurgery.

[A case of young onset cerebral amyloid angiopathy associated with dural grafting]

A 47-year-old man was admitted to our hospital because of sudden-onset motor aphasia and right hemiplegia. His past medical history was notable for left craniotomy and hematoma evacuation following a traumatic brain hemorrhage approximately 40 years earlier, for which dural grafting was performed. He also had a history of three lobar hemorrhages in the left hemisphere since the age of 42 years. Brain CT imaging revealed an acute left frontal lobar hemorrhage. His initial brain MRI conducted at our hospital demonstrated hemorrhagic findings with left hemisphere dominance, including acute and old lobar hemorrhage, cortical superficial siderosis, and cerebral microbleeds. Cerebrospinal fluid analyses demonstrated reduced levels of cerebral amyloid-β 42, and elevated total tau. His apolipoprotein E genotype was ε3/ε3. Whole-exome sequencing did not detect mutations in genes associated with Alzheimer's disease, including presenilin 1, presenilin 2, and amyloid precursor protein. These findings led to a clinical diagnosis of iatrogenic cerebral amyloid angiopathy (CAA) using recently proposed diagnostic criteria, which do not require pathological evaluation of the brain. Iatrogenic CAA should be considered as a cause of lobar hemorrhage in young patients, especially those with a past history of neurosurgery.

Cognitive Impairment and Early-onset Cerebral Amyloid Angiopathy in a Middle-aged Man with a History of Childhood Traumatic Brain Injury

We herein report the a 42-year-old man with early-onset cerebral amyloid angiopathy (CAA) and a history of traumatic brain injury and neurosurgery in childhood. Computed tomography revealed cognitive impairment and recurrent lobar intracerebral hemorrhaging. Magnetic resonance imaging indicated cerebral microbleeds, and Pittsburgh compound B positron emission tomography detected brain amyloid deposition, mainly in the region of trauma and occipital lobes. Interestingly, the patient had no genetic predispositions or relevant family history. This case suggests that a single traumatic brain injury or neurosurgery in childhood can cause early-onset CAA.

Iatrogenic cerebral amyloid angiopathy in older adults

BACKGROUND AND PURPOSE

An increasing number of cases of iatrogenic cerebral amyloid angiopathy (CAA) have now been reported worldwide. Proposed diagnostic criteria require a history of medical intervention with potential for amyloid-β transmission, for example those using cadaveric dura mater or requiring instrumentation of the brain or spinal cord. Clinical presentation occurs after an appropriate latency (usually three or four decades); to date, most patients with iatrogenic CAA have had 'early-onset' disease (compared to sporadic, age-related, CAA), as a consequence of childhood procedures.

RESULTS

We describe five cases of possible iatrogenic CAA in adults presenting in later life (aged 65 years and older); all had prior neurosurgical interventions and presented after a latency suggestive of iatrogenic disease (range 30-39 years). Use of cadaveric dura mater was confirmed in one case, and highly likely in the remainder.

CONCLUSION

The presentation of iatrogenic CAA in older adults widens the known potential spectrum of this disease and highlights the difficulties of making the diagnosis in this age group, and particularly in differentiating iatrogenic from sporadic CAA. Increased vigilance for cases presenting at an older age is essential for furthering our understanding of the clinical phenotype and broader implications of iatrogenic CAA.

Spatial colocalization of imaging markers in iatrogenic cerebral amyloid angiopathy with the site of surgery: A metaanalysis

INTRODUCTION

Iatrogenic cerebral amyloid angiopathy (iCAA) is a rare form of CAA. Imaging features are overlapping with spontaneous CAA. However, in iCAA imaging features have not been systematically described so far. The aim of this metaanalysis was to evaluate if any of the described imaging features showed colocalization with the initial site of surgery.

MATERIAL AND METHODS

A systematic review of the medical literature was performed. Patients with probable iCAA were included if the route of potential entry of amyloid into the CNS was unambiguous.

RESULTS

24 patients from 19 reports could be included. 84 ICHs were reported. 11 of the first ever ICH (69%, p = 0.0498, Fisher's exact test) occurred ipsilateral to the site of the initial surgery, whereas 59% of all ICH (n = 63, p = 0.126, Fisher's exact test) occurred ipsilateral to the site of the initial surgery. No cerebellar hemorrhages (0%) were reported. In 5 of 8 patients, ipsilateral hemorrhagic and non-hemorrhagic manifestations were present before symptom onset and/or occurrence of ICH.

DISCUSSION

This metananalysis of the imaging markers of iCAA revealed a spatial colocalization of first ICH with the site of the surgery. Imaging studies with patients at risk for iCAA after exposure to lyophilized dura should be conducted.

Iatrogenic cerebral amyloid angiopathy: A multinational case series and individual patient data analysis of the literature

BACKGROUND

The transmission of amyloid β (Aβ) in humans leading to iatrogenic cerebral amyloid angiopathy (iCAA) is a novel concept with analogies to prion diseases. However, the number of published cases is low, and larger international studies are missing.

AIMS

We aimed to build a large multinational collaboration on iCAA to better understand the clinical spectrum of affected patients.

METHODS

We collected clinical data on patients with iCAA from Austria, Croatia, Italy, Slovenia, and Spain. Patients were included if they met the proposed Queen Square diagnostic criteria (QSC) for iCAA. In addition, we pooled data on disease onset, latency, and cerebrospinal fluid (CSF) biomarkers from previously published iCAA cases based on a systematic literature review.

RESULTS

Twenty-seven patients (22% women) were included in this study. Of these, 19 (70%) met the criteria for probable and 8 (30%) for possible iCAA. Prior neurosurgical procedures were performed in all patients (93% brain surgery, 7% spinal surgery) at median age of 8 (interquartile range (IQR) = 4-18, range = 0-26 years) years. The median symptom latency was 39 years (IQR = 34-41, range = 28-49). The median age at symptom onset was 49 years (IQR = 43-55, range = 32-70). Twenty-one patients (78%) presented with intracranial hemorrhage and 3 (11%) with seizures.

CONCLUSIONS

Our large international case series of patients with iCAA confirms a wide age boundary for the diagnosis of iCAA. Dissemination of awareness of this rare condition will help to identify more affected patients.

Dural Reconstruction Materials for the Repairing of Spinal Neoplastic Cerebrospinal Fluid Leaks

Spinal tumors often lead to more complex complications than other bone tumors. Nerve injuries, dura mater defect, and subsequent cerebrospinal fluid (CSF) leakage generally appear in spinal tumor surgeries and are followed by serious adverse outcomes such as infections and even death. The use of suitable dura mater replacements to achieve multifunctionality in fluid leakage plugging, preventing adhesions, and dural reconstruction is a promising therapeutic approach. Although there have been innovative endeavors to manage dura mater defects, only a handful of materials have realized the targeted multifunctionality. Here, we review recent advances in dura repair materials and techniques and discuss the relative merits in both preclinical and clinical trials as well as future therapeutic options. With these advances, spinal tumor patients with dura mater defects may be able to benefit from novel treatments.

Case report of iatrogenic cerebral amyloid angiopathy after exposure to Lyodura: an Australian perspective

Background

Recently proposed diagnostic criteria for iatrogenic cerebral amyloid angiopathy (iCAA) have sparked increased recognition of cases across the globe. Whilst these patients tend to have a tumultuous course, much like sporadic CAA, there is a high degree of variability. What is unique in this case is the breadth of clinicoradiological data available, including handwritten surgical notes from 1985. In retrospect, early imaging changes of what would ultimately lead to profound morbidity, were apparent 30 years after inoculation with cadaveric dural tissue.

Aim

In this case study we examine the clinicoradiological features of a case of probable iCAA and draw awareness to the presence of this disease in Australia.

Methods

This case was admitted under the care of the author at the Royal Brisbane and Women's Hospital (RBWH). Clinical details and data were gathered during the patient's care and consent for publication provided by the enduring power of attorney.

Results

This 56-year-old female presented in 2018 with left hemiparesis, neglect, and dysarthria secondary to a large right frontal lobe intracerebral hemorrhage (ICH) without an underlying macrovascular cause. MRI brain demonstrated diffuse superficial siderosis assumed related to previous surgical interventions during the mid-1980s for a Chiari malformation and cervical syrinx. There was evidence of extensive white matter disease, discordant with her lack of cerebrovascular disease risk factors. Brain biopsy confirmed CAA. Archived surgical notes confirmed exposure to Lyodura in 1985 and 1986. Two decades of MRI data were available for review and illustrate the evolution of CAA, from normal post-operative findings to marked and unrecognized abnormalities 4 years prior to her first ICH.

Discussion

This is the first Australian case of probable iatrogenic CAA (iCAA) to have such extensive documentation of clinicoradiological evolution. It demonstrates the aggressive course iCAA can take and provides insights into early disease manifestations, relevant to the more common sporadic cases. A brief review of the history of commercial cadaveric tissue use in Australia highlights enormous changes in medical practice over the last 50 years. Awareness within Australia should be raised for this clinical phenomenon, and cases collated to contribute to the growing international pool of evidence.