Where there is no brain imaging: Safety and diagnostic value of lumbar puncture in patients with neurological disorders in a rural hospital of Central Africa

The current landscape of intracranial aneurysms in Africa: management outcomes, challenges, and strategies-a narrative review

Intracranial aneurysms (IAs) pose complex and potentially life-threatening challenges in Africa, where limited resources, restricted access to specialised healthcare facilities, and disparities in healthcare provision amplify the difficulties of management. Timely diagnosis and treatment are pivotal in preventing complications, including subarachnoid haemorrhage. Treatment options encompass observation, surgical clipping, endovascular coiling, and flow diversion. Positive outcomes observed in IA management in Africa include high survival rates, favourable functional outcomes, successful treatment techniques, and the absence of complications in some cases. However, negative outcomes such as postoperative complications, reduced quality of life, perioperative mortality, and the risk of recurrence persist. Challenges in IA management encompass limited access to diagnostic tools, a scarcity of specialised healthcare professionals, and an unequal distribution of services. Addressing these challenges requires interventions focused on improving access to diagnostic tools, expanding the number of trained professionals, and establishing specialised IA treatment centres. Collaboration, research, and capacity-building efforts hold significant importance in improving patient outcomes and reducing disparities in IA management across Africa.

Charting the Next Road Map for CSF Biomarkers in Alzheimer's Disease and Related Dementias

Clinical prediction of underlying pathologic substrates in people with Alzheimer's disease (AD) dementia or related dementia syndromes (ADRD) has limited accuracy. Etiologic biomarkers - including cerebrospinal fluid (CSF) levels of AD proteins and cerebral amyloid PET imaging - have greatly modernized disease-modifying clinical trials in AD, but their integration into medical practice has been slow. Beyond core CSF AD biomarkers (including beta-amyloid 1-42, total tau, and tau phosphorylated at threonine 181), novel biomarkers have been interrogated in single- and multi-centered studies with uneven rigor. Here, we review early expectations for ideal AD/ADRD biomarkers, assess these goals' future applicability, and propose study designs and performance thresholds for meeting these ideals with a focus on CSF biomarkers. We further propose three new characteristics: equity (oversampling of diverse populations in the design and testing of biomarkers), access (reasonable availability to 80% of people at risk for disease, along with pre- and post-biomarker processes), and reliability (thorough evaluation of pre-analytical and analytical factors influencing measurements and performance). Finally, we urge biomarker scientists to balance the desire and evidence for a biomarker to reflect its namesake function, indulge data- as well as theory-driven associations, re-visit the subset of rigorously measured CSF biomarkers in large datasets (such as Alzheimer's disease neuroimaging initiative), and resist the temptation to favor ease over fail-safe in the development phase. This shift from discovery to application, and from suspended disbelief to cogent ingenuity, should allow the AD/ADRD biomarker field to live up to its billing during the next phase of neurodegenerative disease research.

Barriers to headache care in low- and middle-income countries

Headache disorders are a common cause of disability globally and lead not only to physical disability but also to financial strain, higher rates of mental health disorders such as depression and anxiety, and reduced economic productivity which negatively impacts gross domestic product (GDP) on a national scale. While data about headache are relatively scarce in low- and middle-income countries (LMICs), those available suggest that headache disorders occur on a similar scale in LMICs as they do in high-income countries. In this manuscript, we discuss common clinical, political, economic and social barriers to headache care for people living in LMICs. These barriers, affecting every aspect of headache care, begin with community perceptions and cultural beliefs about headache, include ineffective headache care delivery systems and poor headache care training for healthcare workers, and extend through fewer available diagnostic and management tools to limited therapeutic options for headache. Finally, we review potential solutions to these barriers, including educational interventions for healthcare workers, the introduction of a tiered system for headache care provision, creation of locally contextualized diagnostic and management algorithms, and implementation of a stepped approach to headache treatment.

Continental Survey of Access to Diagnostic Tools and Endovascular Management of Aneurysmal Subarachnoid Hemorrhage in Africa

Rationale: Interventional neurovascular procedures are effective in lowering the burden of mortality and complications resulting from aneurysmal subarachnoid hemorrhage (aSAH). Despite the wide uptake of interventional neurovascular procedures in high-income countries, access to care in low- and middle-income countries remains limited, and little is known about accessibility in Africa. In this survey, we decided to assess access to diagnostic tools and treatment of aSAH in Africa.

Methodology: A Google form e-survey was distributed to African neurosurgery centers accepting responses from January 4th to March 21st 2021. Data on accessibility to diagnostic tools, treatment methodologies, and interventional neuroradiology personnel in African centers were collected. Ninety five percent confidence intervals were computed for each variable.

Results: Data was received from 36 neurosurgical centers in 16 African countries (16/54, 30%). Most centers were public institutions. Ninety four percent of the centers had the necessary resources for a lumbar puncture (LP) and a laboratory for the diagnosis of aSAH. Most centers had at least one computed tomography (CT) scanner, 81% of the centers had access to CT angiography and some had access to conventional angiography. Forty seven percent of the centers could obtain a head CT within 2 h of presentation in an emergency. Sixty one percent of centers provided clipping of intracranial aneurysms whilst only 22% of centers could perform the endovascular treatment. Sixty four percent of centers did not have an endovascular specialist.

Conclusion: This survey highlights health inequity in access to endovascular treatment for aSAH. Lack of diagnostic tools to identify an aneurysm and a shortfall of qualified endovascular specialists are prime reasons for this. Our findings can inform health system strengthening policies including the acquisition of equipment and capacity building in Africa.

High frequency of Taenia solium antigen positivity in patients admitted for neurological disorders in the Rural Hospital of Mosango, Democratic Republic of Congo

Background

The epidemiology of human cysticercosis and neurocysticercosis, caused by the larval stage of the pork tapeworm Taenia solium, is not well known in the Democratic Republic of Congo (DRC). Within a multicenter etiological and diagnostic study conducted by the NIDIAG consortium (“Better Diagnosis for Neglected Infections”) and investigating several challenging syndromes, we consecutively evaluated from 2012 to 2015 all patients older than 5 years presenting with neurological disorders (neurology cohort) and with fever > 7 days (persistent fever cohort) at the rural hospital of Mosango, province of Kwilu, DRC. In both cohorts, etiological diagnosis relied on a systematic set of reference laboratory assays and on pre-established clinical case definitions. No neuroimaging was available in the study hospital. In this study, we determined the frequency of T. solium infection in both cohorts and explored in the neurology cohort its association with specific neurological presentations and final etiological diagnoses.

Methods

We conducted a post-hoc descriptive and analytic study on cysticercosis in the neurology and persistent fever cohorts, based on the presence in serum samples of circulating T. solium antigen using the B158/B60 enzyme-linked immunosorbent assay (ELISA) and of cysticercosis IgG using the LDBIO Cysticercosis Western Blot IgG assay.

Results

For the neurology cohort, 340 samples (of 351 enrolled patients) were available for analysis (males: 46.8%; mean age: 38.9 years). T. solium antigen positivity was found in 43 participants (12.6%; 95% confidence interval [CI] 9.3–16.7%), including 9 of 60 (15%) patients with epilepsy. Among the 148 samples available from the persistent fever cohort (males: 39.9%; mean age: 19.9 years), 7 were positive in the T. solium antigen ELISA (4.7%; 95% CI 1.9–9.5%; P = 0.009 when compared to the neurology cohort). No significant association was found within the neurology cohort between positivity and clinical presentation or final diagnoses. Of note, the IgG antibody-detecting assay was found positive in only four (1.3%) of the participants of the neurology cohort and in none of the persistent fever cohort.

Conclusions

T. solium antigen positivity was found in at least 10% of patients admitted with neurological disorders in the Kwilu province, DRC, with no specific pattern of presentation. Further neuroimaging studies should be used to confirm whether neurocysticercosis is prevalent in this region.

Approaches to understanding COVID-19 and its neurological associations

There is an accumulating volume of research into neurological manifestations of COVID-19. However, inconsistent study designs, inadequate controls, poorly-validated tests, and differing settings, interventions, and cultural norms weaken study quality, comparability, and thus the understanding of the spectrum, burden and pathophysiology of these complications. Therefore, a global COVID-19 Neuro Research Coalition, together with the WHO, has reviewed reports of COVID-19 neurological complications and harmonised clinical measures for future research. This will facilitate well-designed studies using precise, consistent case definitions of SARS-CoV2 infection and neurological complications, with standardised forms for pooled data analyses that non-specialists can use, including in low-income settings. This article is protected by copyright. All rights reserved.

S1 guidelines "lumbar puncture and cerebrospinal fluid analysis" (abridged and translated version)

Introduction

Cerebrospinal fluid (CSF) analysis is important for detecting inflammation of the nervous system and the meninges, bleeding in the area of the subarachnoid space that may not be visualized by imaging, and the spread of malignant diseases to the CSF space. In the diagnosis and differential diagnosis of neurodegenerative diseases, the importance of CSF analysis is increasing. Measuring the opening pressure of CSF in idiopathic intracranial hypertension and at spinal tap in normal pressure hydrocephalus constitute diagnostic examination procedures with therapeutic benefits.Recommendations (most important 3-5 recommendations on a glimpse): The indications and contraindications must be checked before lumbar puncture (LP) is performed, and sampling CSF requires the consent of the patient.Puncture with an atraumatic needle is associated with a lower incidence of postpuncture discomfort. The frequency of postpuncture syndrome correlates inversely with age and body mass index, and it is more common in women and patients with a history of headache. The sharp needle is preferably used in older or obese patients, also in punctures expected to be difficult.In order to avoid repeating LP, a sufficient quantity of CSF (at least 10 ml) should be collected. The CSF sample and the serum sample taken at the same time should be sent to a specialized laboratory immediately so that the emergency and basic CSF analysis program can be carried out within 2 h.The indication for LP in anticoagulant therapy should always be decided on an individual basis. The risk of interrupting anticoagulant therapy must be weighed against the increased bleeding risk of LP with anticoagulant therapy.As a quality assurance measure in CSF analysis, it is recommended that all cytological, clinical-chemical, and microbiological findings are combined in an integrated summary report and evaluated by an expert in CSF analysis.

Conclusions

In view of the importance and developments in CSF analysis, the S1 guideline "Lumbar puncture and cerebrospinal fluid analysis" was recently prepared by the German Society for CSF analysis and clinical neurochemistry (DGLN) and published in German in accordance with the guidelines of the AWMF (https://www.awmf.org). /uploads/tx_szleitlinien/030-141l_S1_Lumbalpunktion_und_Liquordiagnostik_2019-08.pdf). The present article is an abridged translation of the above cited guideline. The guideline has been jointly edited by the DGLN and DGN.

Factors Associated with Incidental Neuroimaging Abnormalities in New Primary Headache Patients

Background and Purpose

Deciding whether or not to perform neuroimaging in primary headache is a dilemma for headache physicians. The aim of this study was to identify clinical predictors of incidental neuroimaging abnormalities in new patients with primary headache disorders.

Methods

This cross-sectional study was based on a prospective multicenter headache registry, and it classified 1,627 consecutive first-visit headache patients according to the third edition (beta version) of the International Classification of Headache Disorders (ICHD-3β). Primary headache patients who underwent neuroimaging were finally enrolled in the analysis. Serious intracranial pathology was defined as serious neuroimaging abnormalities with a high degree of medical urgency. Univariable and multivariable logistic regression analyses were conducted to identify factors associated with incidental neuroimaging abnormalities.

Results

Neuroimaging abnormalities were present in 170 (18.3%) of 927 eligible patients. In multivariable analysis, age ≥40 years [multivariable-adjusted odds ratio (aOR)=3.37, 95% CI=2.07–6.83], male sex (aOR=1.61, 95% CI=1.12–2.32), and age ≥50 years at headache onset (aOR=1.86, 95% CI=1.24–2.78) were associated with neuroimaging abnormalities. In univariable analyses, age ≥40 years was the only independent variable associated with serious neuroimaging abnormalities (OR=3.37, 95% CI=1.17–9.66), which were found in 34 patients (3.6%). These associations did not change after further adjustment for neuroimaging modality.

Conclusions

Incidental neuroimaging abnormalities were common and varied in a primary headache diagnosis. A small proportion of the patients incidentally had serious neuroimaging abnormalities, and they were predicted by age ≥40 years. These findings can be used to guide the performing of neuroimaging in primary headache disorders.

Potential usefulness of C-reactive protein and procalcitonin determination in patients admitted for neurological disorders in rural Democratic Republic of Congo

In low-resource hospitals of central Africa, neurological disorders are frequent and etiologies very diverse. The difficulty to identify invasive bacterial infections in this setting results in major antibiotic overuse. Biomarkers such as C-reactive protein (CRP) and procalcitonin (PCT) may help discriminate these conditions. We retrospectively determined the concentrations of CRP and PCT in the sera of patients consecutively enrolled from 2012 to 2015 in an etiological study on neurological disorders at the rural hospital of Mosango, Democratic Republic of Congo. Invasive bacterial infection had been diagnosed by the demonstration of a bacterial pathogen in cerebrospinal fluid or blood cultures or the presence of radiological pneumonia. Sera of 313 (89.2%) and 317 (90.3%) of the 351 enrolled participants were available for determination of CRP and PCT concentrations respectively. Areas under the receiver operating characteristic curves for invasive bacterial infection, diagnosed in 19 tested cases, were 94.3% for CRP and 91.7% for PCT. No single case had a normal CRP concentration (<10 mg/L). Our data, although limited, suggest that CRP or PCT concentrations may help discriminate invasive bacterial infections in patients with neurological disorders in tropical settings and that normal CRP values could assist in withholding antibiotics.