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- ItemBeliefs, knowledge and attitudes towards Parkinson's disease among a Xhosa speaking black population in South Africa : a cross-sectional study(Elsevier, 2017-08) Mokaya, Jolynne; Carr, Jonathan; Gray, KeithPD is a progressive neurodegenerative disorder characterized by tremor, rigidity, bradykinesia and postural instability [1]. It is classically defined as a motor disorder, however there are a range of non- motor symptoms that occur with advancing age and disease severity[2].
- ItemClinical findings and genetic screening for copy number variation mutations in a cohort of South African patients with Parkinson’s disease(Health & Medical Publishing Group, 2016) Mahne, Anna Cecelia; Carr, Jonathan; Bardien, Soraya; Schutte, Clara MariaENGLISH ABSTRACT: Background. Parkinson’s disease (PD), with a prevalence of up to 4% in Western countries, appears to be less common in Africa, possibly in part because of genetic factors. African studies investigating the genetic causation of PD are limited. Objective. To describe the clinical and genetic findings in a group of black South African patients with PD. Methods. All black African patients with PD from a tertiary hospital neurology clinic were examined. Symptoms were scored according to the Unified Parkinson’s Disease Rating Scale (UPDRS), and patients were classified according to motor features. Genomic DNA was extracted and multiplex ligation-dependent probe amplification was used for detection of copy number variation (CNV) mutations in the known PD-causing genes. Results. Sixteen patients were identified (ages 56 - 82 years). Three had a family history of PD. Classification into motor subtypes showed 44% mixed, 31% akinetic-rigid, and 25% tremor-dominant subtypes. UPDRS scores ranged from 7 to 88, with dementia in 20%. No patient had G2019S LRRK2 and A30P SNCA mutations, and all except one had no CNV mutations in the known PD-causing genes. A female patient (age of onset 50 years, no family history) had a parkin gene heterozygous deletion of exon 4. She had hyperreflexia, bilateral Hoffmann’s reflexes, normal plantar responses and no dystonia. Conclusion. This group of black African patients showed similar characteristics to patients in Western studies, possibly with a higher proportion having tremor-dominant disease. Genetic analysis showed one parkin gene mutation. The limited knowledge on PD-causing genes and mutations in black populations warrants further studies involving next-generation sequencing approaches.
- ItemEEG source connectivity to localize the seizure onset zone in patients with drug resistant epilepsy(Elsevier, 2017-09) Staljanssens, Willeke; Strobbe, Gregor; Van Holen, Roel; Keereman, Vincent; Gadeyne, Stefanie; Carrette, Evelien; Meurs, Alfred; Pittau, Francesca; Momjian, Shahan; Seeck, Margitta; Boon, Paul; Vandenberghe, Stefaan; Vulliemoz, Serge; Vonck, Kristl; Van Mierlo, PieterENGLISH ABSTRACT: the presurgical evaluation of epilepsy as a reflection of the irritative zone. ESI of ictal scalp EEG to localize the seizure onset zone (SOZ) remains challenging. We investigated the value of an approach for ictal imaging using ESI and functional connectivity analysis (FC). Ictal scalp EEG from 111 seizures in 27 patients who had Engel class I outcome at least 1 year following resective surgery was analyzed. For every seizure, an artifact-free epoch close to the seizure onset was selected and ESI using LORETA was applied. In addition, the reconstructed sources underwent FC using the spectrum-weighted Adaptive Directed Transfer Function. This resulted in the estimation of the SOZ in two ways: (i) the source with maximal power after ESI, (ii) the source with the strongest outgoing connections after combined ESI and FC. Next, we calculated the distance between the estimated SOZ and the border of the resected zone (RZ) for both approaches and called this the localization error ((i) LEpow and (ii) LEconn respectively). By comparing LEpow and LEconn, we assessed the added value of FC. The source with maximal power after ESI was inside the RZ (LEpow =0 mm) in 31% of the seizures and estimated within 10 mm from the border of the RZ (LEpow ≤10 mm) in 42%. Using ESI and FC, these numbers increased to 72% for LEconn =0 mm and 94% for LEconn ≤10 mm. FC provided a significant added value to ESI alone (p < 0.001). ESI combined with subsequent FC is able to localize the SOZ in a non-invasive way with high accuracy. Therefore it could be a valuable tool in the presurgical evaluation of epilepsy.
- ItemEmerging differences between Huntington's disease-like 2 and Huntington's disease : a comparison using MRI brain volumetry(Elsevier, 2019) Anderson, David G.; Haagensen, Mark; Ferreira-Correia, Aline; Pierson, Ronald; Carr, Jonathan; Krause, Amanda; Margolis, Russell L.ENGLISH ABSTRACT: Huntington's Disease-Like 2 (HDL2), caused by a CTG/CAG expansion in JPH3 on chromosome 16q24, is the most common Huntington's Disease (HD) phenocopy in populations with African ancestry. Qualitatively, brain MRIs of HDL2 patients have been indistinguishable from HD. To determine brain regions most affected in HDL2 a cross-sectional study using MRI brain volumetry was undertaken to compare the brains of nine HDL2, 11 HD and nine age matched control participants. Participants were ascertained from the region in South Africa with the world's highest HDL2 incidence. The HDL2 and HD patient groups showed no significant differences with respect to mean age at MRI, disease duration, abnormal triplet repeat length, or age at disease onset. Overall, intracerebral volumes were smaller in both affected groups compared to the control group. Comparing the HDL2 and HD groups across multiple covariates, cortical and subcortical volumes were similar with the exception that the HDL2 thalamic volumes were smaller. Consistent with other similarities between the two diseases, these results indicate a pattern of neurodegeneration in HDL2 that is remarkably similar to HD. However smaller thalamic volumes in HDL2 raises intriguing questions into the pathogenesis of both disorders, and how these volumetric differences relate to their respective phenotypes.
- ItemEMG/ENG services rendered by clinical neurophysiology technologists in solo practice(Health & Medical Publishing Group, 1998) Bill, P. L. A.; Fritz, V. U.; Eastman, R. W.; Gledhill, R. F.; Kruger, A. J.; Mafojane, N. A.; Saffer, S. D.; Carr, J.; Van Der Meyden, C. H.[No abstract available]
- ItemListerial brainstem encephalitis – treatable, but easily missed(Health & Medical Publishing Group, 2015) Fredericks, Pearl; Britz, Marcell; Eastman, Roland; Carr, Jonathan; Bateman, Kathleen JaneENGLISH ABSTRACT: Listerial brainstem encephalitis (LBE) is an uncommon form of listerial central nervous system infection that progresses rapidly and is invariably fatal unless detected and treated early. We report on six adult patients with LBE, of whom five were managed or co-managed by our unit during the period January - June 2012. All presented with a short prodromal illness followed by a combination of brainstem signs, including multiple cranial nerve palsies with emphasis on the lower cranial nerves, ataxia, motor and sensory long-tract signs, a depressed level of consciousness and apnoea. In two cases the diagnosis was delayed with adverse outcomes. LBE may be difficult to diagnose: clinicians may not be aware of this condition, the brainstem location may not be recognised readily, general markers of inflammation such as the erythrocyte sedimentation rate, C-reactive protein level or white cell count may be normal, and the cerebrospinal fluid is typically normal or there are only mild and nonspecific findings. Serological tests are unreliable, and diagnosis is achieved through blood cultures, magnetic resonance imaging and clinical recognition.
- ItemParkinson’s disease : a systemic inflammatory disease accompanied by bacterial inflammagens(Frontiers Media, 2019-08-27) Adams, Buin; Nunes, J. Massimo; Page, Martin J.; Roberts, Timothy; Carr, Jonathan; Nell, Theo A.; Kell, Douglas B.; Pretorius, EtheresiaParkinson’s disease (PD) is a well-known neurodegenerative disease with a strong association established with systemic inflammation. Recently, the role of the gingipain protease group from Porphyromonas gingivalis was implicated in Alzheimer’s disease and here we present evidence, using a fluorescent antibody to detect gingipain R1 (RgpA), of its presence in a PD population. To further elucidate the action of this gingipain, as well as the action of the lipopolysaccharide (LPS) from P. gingivalis, low concentrations of recombinant RgpA and LPS were added to purified fluorescent fibrinogen. We also substantiate previous findings regarding PD by emphasizing the presence of systemic inflammation via multiplex cytokine analysis, and demonstrate hypercoagulation using thromboelastography (TEG), confocal and electron microscopy. Biomarker analysis confirmed significantly increased levels of circulating proinflammatory cytokines. In our PD and control blood analysis, our results show increased hypercoagulation, the presence of amyloid formation in plasma, and profound ultrastructural changes to platelets. Our laboratory analysis of purified fibrinogen with added RgpA, and/or LPS, showed preliminary data with regards to the actions of the protease and the bacterial membrane inflammagen on plasma proteins, to better understand the nature of established PD.
- ItemPeritoneal dialysis technique survival at Tygerberg Hospital in Cape Town, South Africa(African Association of Nephrology, 2017) Kapembwa, Kenneth C.; Bapoo, Nabeel A; Tannor, Elliot K.; Davids, M. RazeenBackground: The use of peritoneal dialysis (PD) as a treatment modality for patients with end-stage renal disease (ESRD) has been declining in many countries over the past few years. One of the reasons is technique failure, which occurs more frequently than is the case with chronic haemodialysis. Identifying and addressing the causes of technique failure is important in order to maintain more patients on PD, especially in settings where there are limited resources for chronic haemodialysis and a “PD first” approach is followed. Methods: In this retrospective study at Tygerberg Hospital in Cape Town, South Africa, we investigated 170 patients who were started on chronic ambulatory PD between January 2008 and July 2014, and determined rates of technique and patient survival. Demographic, clinical and laboratory data were assessed to identify risk factors for these outcomes. Results: The median age of the patients was 36 years and the most common cause of ESRD was glomerulonephritis. Only one patient had diabetes mellitus. Technique survival at 1, 3 and 5 years was 80%, 54% and 39%, respectively, while patient survival was 90%, 82% and 63%. Patients started on PD during the second half of the study period had improved rates of technique survival. Peritonitis was the most common cause of technique failure. Increasing age and Black ethnicity were associated with increased likelihood of technique failure. Other clinical and social factors were not significantly associated with the occurrence of technique failure. Conclusions: In our patients on PD, peritonitis, increased age and Black ethnicity were important factors associated with the development of technique failure. Concerted efforts are required to reduce peritonitis rates at our centre as this is the leading cause of technique failure.
- ItemA putative founder effect for Parkinson’s disease in South African Afrikaners(Health & Medical Publishing Group, 2014-06) Carr, Jonathan; Van Coller, RiaanThere is evidence for a founder effect for Parkinson’s disease in South African Afrikaners. This finding is of importance for two reasons. Firstly, given that established genetic causes of PD have not been identified in the Afrikaner population, it appears likely that this population carries unique mutations that remain to be identified by genome-wide screening. Secondly, in the event that effective treatments are developed, particularly for presymptomatic patients, the Afrikaner population may be considered to be at risk and requiring careful assessment with accurate biomarkers.
- ItemReliability and diagnostic performance of CT imaging criteria in the diagnosis of Tuberculous Meningitis(PLOS One, 2012-06) Botha, Hugo; Ackerman, Christelle; Candy, Sally; Carr, Jonathan; Griffith-Richards, Stephanie; Bateman, Kathleen J.Introduction: Abnormalities on CT imaging may contribute to the diagnosis of tuberculous meningitis (TBM). Recently, an expert consensus case definition (CCD) and set of imaging criteria for diagnosing basal meningeal enhancement (BME) have been proposed. This study aimed to evaluate the sensitivity, specificity and reliability of these in a prospective cohort of adult meningitis patients. Methods: Initial diagnoses were based on the CCD, classifying patients into: ‘Definite TBM’ (microbiological confirmation), ‘Probable TBM’ (diagnostic score $10), ‘Possible TBM’ (diagnostic score 6–9), ‘Not TBM’ (confirmation of an alternative diagnosis) or ‘Uncertain’ (diagnostic score of ,6). CT images were evaluated independently on two occasions by four experienced reviewers. Intra-rater and inter-rater agreement were calculated using the kappa statistic. Sensitivities and specificities were calculated using both ‘Definite TBM’ and either ‘Definite TBM’ or ‘Probable TBM’ as gold standards. Results: CT scan criteria for BME had good intra-rater agreement (k range 0.35–0.78) and fair to moderate inter-rater agreement (k range 0.20–0.52). Intra- and inter-rater agreement on the CCD components were good to fair (k = ranges 0.47–0.81 and 0.21–0.63). Using ‘Definite TBM’ as a gold standard, the criteria for BME were very specific (61.5%–100%), but insensitive (5.9%–29.4%). Similarly, the imaging components of the CCD were highly specific (69.2–100%) but lacked sensitivity (0–56.7%). Similar values were found when using ‘Definite TBM’ or ‘Probable TBM’ as a gold standard. Discussion: The fair to moderate inter-rater agreement and poor sensitivities of the criteria for BME suggest that little reliance should be placed in these features in isolation. While the presence of the CCD criteria of acute infarction or tuberculoma(s) appears useful as rule-in criteria, their absence is of little help in excluding TBM. The CCD and criteria for BME, as well as any new criteria, need to be standardized and validated in prospective cohort studies.
- ItemStandards for the assessment of visual evoked potentials in an ethnically heterogeneous adult population(Health and Medical Publishing Group -- HMPG, 1985-02) De Graaf, A. S.; Lombard, C. J.; Hart, G. L.Visual evoked potentials (VEPs) were recorded by chequerboard pattern-reversal stimulation in 276 normal adult subjects aged 15-73 years. The sample comprised comparable white, coloured and black groups of both sexes. Significantly shorter latencies of the major positive component were found in both male and female black subjects compared with those in whites. No significant differences were found between the amplitudes in the different population groups, but females in each population group showed significantly higher amplitudes of the major positive component than males. There was a close relationship between latency and amplitude for both right and left eyes. Except in coloured females, a nonlinear relationship of the major positive component with age was demonstrated, the shortest latency being at about 35 years of age. It is suggested that the following criteria be used in the evaluation of VEP recordings: latency as well as the difference between latencies and amplitudes of the two sides of the major positive component (P1) as compared with standardized values for ethnic, sex and age groups.
- ItemStem cell therapy and amyotrophic lateral sclerosis(Health and Medical Publishing Group (HMPG), 2012-06) Henning, Franclo; Carr, JonathanWe have been made aware of several patients with neurological diseases attending stem cell therapy centres, and in particular individuals with amyotrophic lateral sclerosis (ALS). The opening of stem cell clinics in South Africa has led to an increased number of patients pursuing this therapy at great financial cost and with high expectations.
- ItemTask analysis in neurosciences programme design - neurological problems in general practice(Health and Medical Publishing Group -- HMPG, 1983-02) Gledhill, R. F.Defining educational objectives is the key to achieving the goal of professional competence in students. The technique of task analysis was selected to determine components of competence in clinical neurology appropriate to the needs of primary care. A survey of neurological problems in general practice revealed that these constitute a significant proportion of consultations, and that teaching programmes have failed to provide the appropriate knowledge and skills to manage the commonest problems effectively. Consideration is given to innovations in curriculum and programme design whereby the graduating student might be more suitably prepared to give primary care.
- ItemUse of phenobarbitone for treating childhood epilepsy in resource-poor countries(Health & Medical Publishing Group, 2005) Wilmshurst, J. M.; Van Toorn, R.[No abstract available]