Role and Relevance of Cerebrospinal Fluid Cells in Diagnostics and Research: State-of-the-Art and Underutilized Opportunities

Characterization and diagnosis spectrum of patients with cerebrospinal fluid pleocytosis

PURPOSE

There is an overlap in the cerebrospinal fluid (CSF) characteristics of patients presenting with different etiologies of CSF pleocytosis. Here, we characterized patients with CSF pleocytosis treated in a large hospital.

METHODS

A retrospective cohort study of 1150 patients with an elevated CSF leukocyte count > 5 cells/µl treated at a university hospital in Germany from January 2015 to December 2017 was performed. Information on clinical presentation, laboratory parameters, diagnosis and outcome was collected. Clinical and laboratory features were tested for their potential to differentiate between bacterial meningitis (BM) and other causes of CSF pleocytosis.

RESULTS

The most common etiologies of CSF pleocytosis were CNS infections (34%: 20% with detected pathogen, 14% without), autoimmune (21%) and neoplastic diseases (16%). CSF cell count was higher in CNS infections with detected pathogen (median 82 cells/µl) compared to autoimmune (11 cells/µl, p = 0.001), neoplastic diseases (19 cells/µl, p = 0.01) and other causes (11 cells/µl, p < 0.001). The CHANCE score was developed to differentiate BM from other causes of CSF pleocytosis: Multivariate regression revealed that CSF cell count > 100 cells/µl, CSF protein > 100 mg/dl, CRP > 5 mg/dl, elevated white blood cell count, abnormal mental status and nuchal rigidity are important indicators. The CHANCE score identified patients with BM with high sensitivity (92.1%) and specificity (90.9%) (derivation cohort: AUC: 0.955, validation cohort: AUC: 0.956).

CONCLUSION

Overall, the most common causes for CSF pleocytosis include infectious, neoplastic or autoimmune CNS diseases in ~ 70% of patients. The CHANCE score could be of help to identify patients with high likelihood of BM and support clinical decision making.

Case Report: Treatment of Akinetic Mutism after Unilateral Anterior Cerebral Artery Infarction with Methylphenidate and Levodopa/Benserazide

Introduction

Akinetic mutism is a severe state of impaired volition that can result from a stroke. Its therapeutic evidence relies on single case reports that used atomoxetine or levodopa with variable latency and efficacy.

Case Presentation

We present the case of a 54-year-old woman who developed akinetic mutism after infarction in the territory of the right anterior cerebral artery, successfully treated with methylphenidate and levodopa/benserazide. Clinical examination showed a patient lacking any spontaneous speech and movement while opening her eyes and fixating. Suspecting akinetic mutism after a comprehensive diagnostic work-up, we started an individual therapy attempt with methylphenidate 10 mg and levodopa/benserazide 100/25 mg twice daily. Both drugs affect the dopaminergic and noradrenergic transmission in the frontal-subcortical circuit, compromised in akinetic mutism. We saw rapid and sustained improvement in her volitional actions, devoid of side effects. Finally, the patient was actively communicating and moving her limbs.

Conclusion

We discuss the patient's favorable clinical course in response to the synergistic combination of methylphenidate and levodopa/benserazide, emerging as a promising treatment strategy, and provide a brief literature review of treatment options in akinetic mutism following stroke.

The Diagnostic Dilemma of "The Great Imitator": Heart and Cerebral Involvement of Lupus Manifesting as Bilateral Upper and Lower Extremity Weakness

Background

Systemic lupus erythematous (SLE) is an autoimmune condition which can cause complex, multiorgan dysfunction. This autoimmune disease is caused by the production of antinuclear antibodies which allows this disease to target virtually any organ in the human body. When a patient experiences an unpredictable worsening of disease activity, it is generally considered a lupus flare. Organ dysfunction due to a lupus flare tends to manifest as separate events in the literature and rarely do we witness multiple compounding organ failures during a lupus flare. If we do witness organ dysfunction and failure, rarely do we see cardiac and cerebral involvement. Typically, patients take immunosuppressants for a long term to avoid the patient's disease process from worsening and to provide prophylaxis from a flare to occur. Despite the availability in preventive strategies, some patients will have increased disease activity multiple times throughout their lifetime and will need increases in their medication doses or changes to their regimen. Some flares can be managed in the clinic, but more severe ones may be life-threatening that they require intravenous medications and hospitalization to achieve remission. In the following case, we see a patient with a past medical history of SLE on multiple immunosuppressants who arrived at the hospital with acute, bilateral weakness of the upper and lower extremities. It was later determined via various imaging and laboratory testing that she was having an SLE flare that was directly causing myocarditis which progressed to global ischemia of the brain via myocardial hypoperfusion. She experienced substantial recovery from her flare with treatment with high-dose, intravenous corticosteroids. Case Report. A 27-year-old female with a 2-year history of lupus and a 1-week history of paroxysmal atrial fibrillation presented with three days of bilateral focal neurological deficits in the arms and legs. She was found to have ischemic cardiac and neurologic manifestations during her hospital stay.

Conclusion

Our patient presented with reversible focal neurological deficits, elevated high-sensitive troponin levels, and high lupus serum antibodies who showed significant improvement after the introduction of high-dose steroids. This case recommends keeping a large differential and to not discount patients' past comorbidities for causing atypical symptomatology.

Intrathecal delivery of Macromolecules: Clinical status and emerging technologies

The proximity and association of cerebrospinal fluid (CSF) and the intrathecal (IT) space with deep targets in the central nervous system (CNS) parenchyma makes IT injection an attractive route of administration for brain drug delivery. However, the extent to which intrathecally administered macromolecules are effective in treating neurological diseases is a question of both clinical debate and technological interest. We present the biological, chemical, and physical properties of the intrathecal space that are relevant to drug absorption, distribution, metabolism, and elimination from CSF. We then analyze the evolution of IT drug delivery in clinical trials over the last 20 years. Our analysis revealed that the percentage of clinical trials assessing IT delivery for the delivery of biologics (i.e., macromolecules, cells) for treatment of chronic conditions (e.g., neurodegeneration, cancer, and metabolic diseases) has steadily increased. Clinical trials exploring cell or macromolecular delivery within the IT space have not evaluated engineering technologies, such as depots, particles, or other delivery systems. Recent pre-clinical studies have evaluated IT macromolecule delivery in small animals, postulating that delivery efficacy can be assisted by external medical devices, micro- or nanoparticles, bulk biomaterials, and viral vectors. Further studies are necessary to evaluate the extent to which engineering technologies and IT administration improve CNS targeting and therapeutic outcome.

Single-Cell RNA Sequencing of Cerebrospinal Fluid as an Advanced Form of Liquid Biopsy for Neurological Disorders

Diagnosis and longitudinal monitoring of neurological diseases are limited by the poor specificity and limited resolution of currently available techniques. Analysis of circulating cells in cerebrospinal fluid (CSF) has emerged as a promising strategy for the diagnosis, molecular characterization, and monitoring of neurological disease. In comparison to bulk sequencing analysis, single-cell sequencing studies can provide novel insights into rare cell populations and uncover heterogeneity in gene expression at a single-cell resolution, which has several implications for understanding disease pathology and treatment. Parallel development of standardized biofluid collection protocols, pre-processing strategies, reliable single-cell isolation strategies, downstream genomic analysis, and robust computational analysis is paramount for comprehensive single-cell sequencing analysis. Here we perform a comprehensive review of studies focusing on single-cell sequencing of cells in the CSF of patients with oncological or non-oncological diseases of the central nervous system.