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2.
Alzheimers Res Ther ; 13(1): 50, 2021 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-33608039

RESUMEN

BACKGROUND: Dementia with Lewy bodies (DLB) and dementia in Parkinson's disease (PDD) are recognised to be under-recognised in clinical practice in the UK, with only one third to a half of expected cases diagnosed. We aimed to assess whether clinical diagnostic rates could be increased by the introduction of a structured assessment toolkit for clinicians. METHODS: We established baseline diagnostic rates for DLB and PDD in four memory clinics and three movement disorder/Parkinson's disease (PD) clinics in two separate geographical regions in the UK. An assessment toolkit specifically developed to assist with the recognition and diagnosis of DLB and PDD was then introduced to the same clinical teams and diagnostic rates for DLB and PDD were reassessed. For assessing DLB diagnosis, a total of 3820 case notes were reviewed before the introduction of the toolkit, and 2061 case notes reviewed after its introduction. For PDD diagnosis, a total of 1797 case notes were reviewed before the introduction of the toolkit and 3405 case notes after it. Mean values and proportions were analysed using Student's t test for independent samples and χ2 test, respectively. RESULTS: DLB was diagnosed in 4.6% of dementia cases prior to the introduction of the toolkit, and 6.2% of dementia cases afterwards, an absolute rise of 1.6%, equal to a 35% increase in the number of DLB cases diagnosed when using the toolkit (χ2 = 4.2, P = 0.041). The number of PD patients diagnosed with PDD was not found overall to be significantly different when using the toolkit: 9.6% of PD cases before and 8.2% of cases after its introduction (χ2 = 1.8, P = 0.18), though the ages of PD patients assessed after the toolkit's introduction were lower (73.9 years vs 80.0 years, t = 19.2, p < 0.001). CONCLUSION: Introduction of the assessment toolkit was associated with a significant increase in the rate of DLB diagnosis, suggesting that a structured means of assessing symptoms and clinical features associated with DLB can assist clinicians in recognising cases. The assessment toolkit did not alter the overall rate of PDD diagnosis, suggesting that alternate means may be required to improve the rate of diagnosis of dementia in Parkinson's disease.


Asunto(s)
Enfermedad por Cuerpos de Lewy , Enfermedad de Parkinson , Anciano , Humanos , Enfermedad por Cuerpos de Lewy/diagnóstico , Enfermedad por Cuerpos de Lewy/epidemiología , Memoria , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/epidemiología
3.
Sci Rep ; 10(1): 12985, 2020 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-32737390

RESUMEN

As whales recover from commercial exploitation, they are increasing in abundance in habitats that they have been absent from for decades. However, studying the recovery and habitat use patterns of whales, particularly in remote and inaccessible regions, frequently poses logistical and economic challenges. Here we trial a new approach for measuring whale density in a remote area, using Very-High-Resolution WorldView-3 satellite imagery. This approach has capacity to provide sightings data to complement and assist traditional sightings surveys. We compare at-sea whale density estimates to estimates derived from satellite imagery collected at a similar time, and use suction-cup archival logger data to make an adjustment for surface availability. We demonstrate that satellite imagery can provide useful data on whale occurrence and density. Densities, when unadjusted for surface availability are shown to be considerably lower than those estimated by the ship survey. However, adjusted for surface availability and weather conditions (0.13 whales per km2, CV = 0.38), they fall within an order of magnitude of those derived by traditional line-transect estimates (0.33 whales per km2, CV = 0.09). Satellite surveys represent an exciting development for high-resolution image-based cetacean observation at sea, particularly in inaccessible regions, presenting opportunities for ongoing and future research.


Asunto(s)
Ecosistema , Imágenes Satelitales , Navíos , Ballenas/fisiología , Animales , Densidad de Población
4.
Clin Microbiol Infect ; 26(7): 842-847, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32344166

RESUMEN

BACKGROUND: The COVID-19 pandemic caused by SARS-CoV-2 remains a significant issue for global health, economics and society. A wealth of data has been generated since its emergence in December 2019, and it is vital for clinicians to keep up with this data from across the world at a time of uncertainty and constantly evolving guidelines and clinical practice. OBJECTIVES: Here we provide an update for clinicians on the recent developments in the virology, diagnostics, clinical presentation, viral shedding, and treatment options for COVID-19 based on current literature. SOURCES: We considered published peer-reviewed papers and non-peer-reviewed pre-print manuscripts on COVID19 and related aspects with an emphasis on clinical management aspects. CONTENT: We describe the virological characteristics of SARS-CoV-2 and the clinical course of COVID-19 with an emphasis on diagnostic challenges, duration of viral shedding, severity markers and current treatment options. IMPLICATIONS: The key challenge in managing COVID-19 remains patient density. However, accurate diagnosis as well as early identification and management of high-risk severe cases are important for many clinicians. For improved management of cases, there is a need to understand test probability of serology, qRT-PCR and radiological testing, and the efficacy of available treatment options that could be used in severe cases with a high risk of mortality.


Asunto(s)
Betacoronavirus/patogenicidad , Control de Enfermedades Transmisibles/métodos , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/patología , Neumonía Viral/diagnóstico , Neumonía Viral/patología , Betacoronavirus/genética , Betacoronavirus/fisiología , COVID-19 , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Humanos , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , SARS-CoV-2 , Esparcimiento de Virus/fisiología
5.
Eur J Clin Microbiol Infect Dis ; 39(7): 1287-1294, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32124106

RESUMEN

Enhanced surveillance for CREs was established at national sentinel sites in South Africa. We aimed to apply an epidemiological and microbiological approach to characterise CREs and to assess trends in antimicrobial resistance from patients admitted to tertiary academic hospitals. A retrospective analysis was conducted on patients of all ages with CRE bacteraemia admitted at any one of 12 tertiary academic hospitals in four provinces (Gauteng, KwaZulu-Natal, Western Cape and Free State) in South Africa. The study period was from July 2015 to December 2018. A case of CRE bacteraemia was defined as a patient admitted to one of the selected tertiary hospitals where any of the Enterobacteriaceae was isolated from a blood culture, and was resistant to the carbapenems (ertapenem, meropenem, imipenem and/or doripenem) or had a positive result for the Modified Hodge Test (MHT) according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. A positive blood culture result obtained after 21 days of the last blood culture result was regarded as a new case. To distinguish hospital-acquired (HA) from the community-acquired (CA) bacteraemia, the following definitions were applied: the HA CRE bacteraemia was defined as a patient with CRE isolated from blood culture ≥ 72 h of hospital admission or with any prior healthcare contact, within 1 year prior to the current episode or referral from a healthcare facility where the patient was admitted before the current hospital. A case of the CA CRE bacteraemia was defined as a patient with CRE isolated from blood culture < 72 h of hospital admission and with no prior healthcare contact. The majority of carbapenem-resistant Enterobacteriaceae (CRE) (70%) were hospital-acquired (HA) with Klebsiella pneumoniae being the predominant species (78%). In-hospital mortality rate was 38%. The commonest carbapenemase genes were bla-OXA-48 (52%) and bla-NDM (34%). The high mortality rate related to bacteraemia with CRE and the fact that most were hospital-acquired infections highlights the need to control the spread of these drug-resistant bacteria. Replacement with OXA-48 is the striking finding from this surveillance analysis. Infection control and antibiotic stewardship play important roles in decreasing the spread of resistance.


Asunto(s)
Bacteriemia/epidemiología , Bacteriemia/microbiología , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/microbiología , Centros de Atención Terciaria/estadística & datos numéricos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Proteínas Bacterianas/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/clasificación , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , ADN Bacteriano/genética , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Monitoreo Epidemiológico , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos , Factores de Riesgo , Sudáfrica/epidemiología , beta-Lactamasas/genética
6.
S Afr Med J ; 109(12): 934-940, 2019 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-31865955

RESUMEN

BACKGROUND: In South Africa (SA), the National Department of Health has developed an Antimicrobial Resistance National Strategy Framework document to manage antimicrobial resistance (AMR). One of the strategic objectives is to optimise surveillance and early detection of AMR. At the National Institute for Communicable Diseases (NICD), an analysis of selected organisms and antimicrobial agents from both the public and the private sectors was conducted. OBJECTIVES: The relevance of surveillance for AMR is increasingly recognised in the light of global action plans to combat resistance. In this report, we present an overview of ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp.) organisms and Escherichia coli reported from public and private sector laboratories in SA for the period 2016 - 2017. METHODS: Antimicrobial susceptibility testing (AST) profiles on selected ESKAPE organisms and E. coli isolated from blood cultures from the public and private sectors in 2016 and 2017 were analysed. AST data were extracted from a web-based electronic platform created by the NICD. Drug-bug combinations following the World Health Organization's Global Antimicrobial Surveillance System guidelines were included in the analysis. RESULTS: A total of 28 920 ESKAPE organisms and E. coli were reported in 2016 and 32 293 in 2017 across the two health sectors. Proportions of some organisms differed between the two health sectors, such as E. coli (19% in the public sector and 36% in the private sector), A. baumannii (14% public and 4% private), P. aeruginosa (7% public and 11% private) and S. aureus (27% public and 17% private). Susceptibility data indicated changing patterns in both sectors towards an increase in non-susceptibility to carbapenems in K. pneumoniae (p<0.01). However, we demonstrated an increase in susceptibility to cloxacillin in S. aureus (p<0.01) in both sectors. CONCLUSIONS: The key clinically important finding is the rapidly decreasing carbapenem susceptibility among Enterobacteriaceae reported in SA, irrespective of sector. In addition, the analysis provides information that could be used to monitor the effectiveness of interventions implemented at a national level under the guidance and direction of the national AMR framework.


Asunto(s)
Antibacterianos/farmacología , Bacteriemia/microbiología , Farmacorresistencia Bacteriana , Vigilancia de la Población , Sector Privado/estadística & datos numéricos , Sector Público/estadística & datos numéricos , Acinetobacter baumannii/efectos de los fármacos , Cultivo de Sangre , Enterobacter/efectos de los fármacos , Enterococcus faecium/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Humanos , Klebsiella pneumoniae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacos , Sudáfrica , Staphylococcus aureus/efectos de los fármacos
7.
S Afr Med J ; 108(5): 386-388, 2018 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-29843850

RESUMEN

A 34-year-old HIV-positive man with a history of chronic substance abuse was admitted with dual infection of Streptococcus pneumoniae and Listeria monocytogenes. Combined bacteraemia with S. pneumoniae and L. monocytogenes is very rare. To the best of our knowledge, this is the first such case documented at our institution and in South Africa. Ampicillin should be added to antibiotic regimens to improve patient outcome if L. monocytogenes infection is suspected. Co-infections that occur with L. monocytogenes may have conflicting antibiotic treatment options. This case report emphasises the need for a good relationship between the local microbiology pathologist and physician to select appropriate antibiotic treatment before definitive results are available.


Asunto(s)
Ampicilina/administración & dosificación , Ceftriaxona/administración & dosificación , Seropositividad para VIH/sangre , Listeria monocytogenes/aislamiento & purificación , Listeriosis , Neumonía Neumocócica , Streptococcus pneumoniae/aislamiento & purificación , Adulto , Anemia/diagnóstico , Anemia/terapia , Antibacterianos/administración & dosificación , Transfusión Sanguínea/métodos , Recuento de Linfocito CD4/métodos , Coinfección/diagnóstico , Coinfección/inmunología , Coinfección/fisiopatología , Coinfección/terapia , Resultado Fatal , VIH/inmunología , Humanos , Listeriosis/diagnóstico , Listeriosis/inmunología , Listeriosis/fisiopatología , Listeriosis/terapia , Masculino , Insuficiencia Multiorgánica/diagnóstico , Insuficiencia Multiorgánica/etiología , Neumonía Neumocócica/diagnóstico , Neumonía Neumocócica/inmunología , Neumonía Neumocócica/fisiopatología , Neumonía Neumocócica/terapia , Respiración Artificial/métodos
8.
Psychol Med ; 47(13): 2358-2368, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28464963

RESUMEN

BACKGROUND: Cognitive deficits in schizophrenia have major functional impacts. Modafinil is a cognitive enhancer whose effect in healthy volunteers is well-described, but whose effects on the cognitive deficits of schizophrenia appear to be inconsistent. Two possible reasons for this are that cognitive test batteries vary in their sensitivity, or that the phase of illness may be important, with patients early in their illness responding better. METHODS: A double-blind, randomised, placebo-controlled single-dose crossover study of modafinil 200 mg examined this with two cognitive batteries [MATRICS Consensus Cognitive Battery (MCCB) and Cambridge Neuropsychological Test Automated Battery (CANTAB)] in 46 participants with under 3 years' duration of DSM-IV schizophrenia, on stable antipsychotic medication. In parallel, the same design was used in 28 age-, sex-, and education-matched healthy volunteers. Uncorrected p values were calculated using mixed effects models. RESULTS: In patients, modafinil significantly improved CANTAB Paired Associate Learning, non-significantly improved efficiency and significantly slowed performance of the CANTAB Stockings of Cambridge spatial planning task. There was no significant effect on any MCCB domain. In healthy volunteers, modafinil significantly increased CANTAB Rapid Visual Processing, Intra-Extra Dimensional Set Shifting and verbal recall accuracy, and MCCB social cognition performance. The only significant differences between groups were in MCCB visual learning. CONCLUSIONS: As in earlier chronic schizophrenia studies, modafinil failed to produce changes in cognition in early psychosis as measured by MCCB. CANTAB proved more sensitive to the effects of modafinil in participants with early schizophrenia and in healthy volunteers. This confirms the importance of selecting the appropriate test battery in treatment studies of cognition in schizophrenia.


Asunto(s)
Compuestos de Bencidrilo/farmacología , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/fisiopatología , Pruebas Neuropsicológicas , Nootrópicos/farmacología , Evaluación de Resultado en la Atención de Salud , Esquizofrenia/fisiopatología , Adolescente , Adulto , Compuestos de Bencidrilo/administración & dosificación , Disfunción Cognitiva/etiología , Estudios Cruzados , Método Doble Ciego , Femenino , Voluntarios Sanos , Humanos , Masculino , Modafinilo , Nootrópicos/administración & dosificación , Esquizofrenia/complicaciones , Adulto Joven
9.
S Afr Med J ; 104(3): 183-6, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24897820

RESUMEN

BACKGROUND: There is an alarming global increase in the incidence of nosocomial infections with multidrug-resistant Gram-negative bacteria, which are often only susceptible to colistin. Colistin was developed prior to current methods of establishing dosing using pharmacokinetic-pharmacodynamic relationships. Dosing regimens differ in package inserts from different manufacturers and in different guidelines. It is imperative to avoid under-dosing with colistin in order to limit the development of resistance, as it is the last line of defence. METHODS: We conducted a systematic review of the literature to develop guidelines for rational dosing of intravenous colistin, with a particular focus on critically ill patients. RESULTS: Colistin is administered as the inactive pro-drug colistimethate sodium. Colistin demonstrates concentration-dependent bacterial killing, suggesting that higher doses should be administered less frequently to achieve higher peak concentrations. Dose-related nephrotoxicity occurs, making it impossible to safely achieve concentrations that prevent the selection of resistant mutants or the effective eradication of bacteria with higher minimum inhibitory concentrations. Theoretically, combination therapy should be used to reduce the risk of selection of resistant bacteria. In critically ill patients, a loading dose should be given to rapidly achieve therapeutic concentrations, followed by maintenance doses of 4.5 MU 12-hourly. Maintenance dose adjustment is necessary with renal impairment. CONCLUSION: Easier access to colistin is needed in South Africa, where it is not a registered medicine. Further research is needed to better characterise colistin's pharmacokinetic-pharmacodynamic relationships in humans and to establish whether combinations of colistin with other antimicrobials result in improved clinical outcomes or a reduction in selection of resistant bacteria.


Asunto(s)
Colistina/administración & dosificación , Colistina/farmacocinética , Enfermedad Crítica , Medicina Basada en la Evidencia , Bacterias Gramnegativas/efectos de los fármacos , Humanos , Inyecciones Intravenosas
12.
Mol Oral Microbiol ; 25(6): 369-83, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21040511

RESUMEN

Interactions with fibronectin are important in the virulence strategies of a range of disease-related bacteria. The periodontitis-associated oral spirochaete Treponema denticola expresses at least two fibronectin-binding proteins, designated Msp (major surface protein) and OppA (oligopeptide-binding protein homologue). To identify other T. denticola outer membrane fibronectin-binding proteins, the amino acid sequence of the Treponema pallidum fibronectin-binding protein Tp0155 was used to survey the T. denticola genome. Seven T. denticola genes encoding orthologous proteins were identified. All but two were expressed in Escherichia coli and purified recombinant proteins bound fibronectin. Using antibodies to the N-terminal region of Tp0155, it was demonstrated that T. denticola TDE2318, with highest homology to Tp0155, was cell surface localized. Like Tp0155, the seven T. denticola proteins contained an M23 peptidase domain and four (TDE2318, TDE2753, TDE1738, TDE1297) contained one or two LysM domains. M23 peptidases can degrade peptidoglycan whereas LysM domains recognize carbohydrate polymers. In addition, TDE1738 may act as a bacteriocin based on homology with other bacterial lysins and the presence of an adjacent gene encoding a putative immunity factor. Collectively, these results suggest that T. denticola expresses fibronectin-binding proteins associated with the cell surface that may also have cell wall modifying or lytic functions.


Asunto(s)
Adhesinas Bacterianas/análisis , Fibronectinas/análisis , Péptido Hidrolasas/análisis , Treponema denticola/metabolismo , Secuencias de Aminoácidos/genética , Adhesión Bacteriana/genética , Proteínas de la Membrana Bacteriana Externa/análisis , Proteínas Bacterianas/análisis , Bacteriocinas/metabolismo , Western Blotting , Proteínas Portadoras/análisis , Secuencia de Consenso/genética , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Genoma Bacteriano/genética , Humanos , Lipoproteínas/análisis , Proteínas de la Membrana/análisis , Oligopéptidos/análisis , Sistemas de Lectura Abierta/genética , Peptidoglicano/metabolismo , Plásmidos/genética , Homología de Secuencia de Aminoácido , Treponema denticola/genética , Treponema denticola/patogenicidad , Treponema pallidum/genética
13.
Int J Infect Dis ; 14(5): e423-8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19889562

RESUMEN

OBJECTIVES: To assess the risk of nosocomial transmission by confirmed pulmonary tuberculosis (PTB) patients in a high TB/HIV incidence environment. METHODS: Between November 2006 and April 2007, we carried out a cross-sectional survey of PTB patients with positive smears or cultures at an academic tertiary hospital in the Western Cape, South Africa. RESULTS: Of 394 confirmed PTB patients, only 199 (50.5%) had a known HIV status, of whom 107 (53.8%) were HIV-co-infected. Sensitivity testing for Mycobacterium tuberculosis (TB) was done in 49.3% of patients with available cultures (140/284). Of these patients, 9.3% (13/140) had multidrug-resistant (MDR) TB strains. The turnaround times (TAT) for culture and susceptibility testing were delayed: mean TAT for cultures was 27 days (range 63 days) and for susceptibility testing was 42 days (range 63 days). One fifth of PTB patients (82/394) were diagnosed from wards that do not deal with TB on a daily basis. PTB inpatients were hospitalized for an average of 13 days and were on average transferred twice. Only 14.2% of all PTB patients were notified to the South Africa Provincial Department of Health. Throughout their hospitalization, PTB patients were potentially infectious. CONCLUSIONS: The potential for nosocomial TB transmission in a setting of high TB and HIV co-infection with a high MDR prevalence, inconsistent infection prevention and control measures, and delayed diagnosis cannot be ignored. Barriers to TB infection control must urgently be addressed.


Asunto(s)
Mycobacterium tuberculosis/crecimiento & desarrollo , Tuberculosis Resistente a Múltiples Medicamentos/transmisión , Tuberculosis Pulmonar/transmisión , Adolescente , Adulto , Niño , Preescolar , Estudios de Cohortes , Estudios Transversales , Transmisión de Enfermedad Infecciosa , Femenino , Humanos , Lactante , Modelos Logísticos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/aislamiento & purificación , Sudáfrica/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/microbiología , Adulto Joven
14.
Arch Dis Child ; 95(1): 48-50, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19723640

RESUMEN

Fine needle aspiration biopsy (FNAB) offers a simple outpatient technique for specimen collection in child tuberculosis suspects with peripheral lymphadenopathy. To perform FNAB with mycobacterial culture on an outpatient basis requires use of a sterile transport medium to facilitate bedside inoculation, maintain organism viability and reduce contamination risk en route to the laboratory. The mycobacterial yield and time to positive culture following bedside inoculation into standard mycobacterial growth indicator tubes were compared with initial inoculation into an inexpensive "in-house" liquid growth medium. Of 150 FNAB performed, 57 (38%) cultured Mycobacterium tuberculosis complex. There was one case each with non-tuberculous mycobacteria and Mycobacterium bovis BCG; the remaining 55 being M tuberculosis. Results were concordant in 142 (94.7%) bedside and laboratory inoculation pairs. There was no significant difference in time to positive culture between bedside and laboratory inoculation (16.2 days (SD 0.87) vs 17.1 days (SD 0.85)). Provision of inexpensive specimen transport bottles and practical tuition in FNAB should improve cost-effective diagnosis of tuberculosis at the primary healthcare level.


Asunto(s)
Medios de Cultivo , Mycobacterium tuberculosis/aislamiento & purificación , Manejo de Especímenes/métodos , Tuberculosis Ganglionar/diagnóstico , Adolescente , Técnicas Bacteriológicas/métodos , Biopsia con Aguja Fina/métodos , Niño , Preescolar , Humanos , Lactante , Mycobacterium tuberculosis/crecimiento & desarrollo , Transportes/métodos
15.
Artículo en Inglés | AIM (África) | ID: biblio-1270635

RESUMEN

Providing rapid results for blood culture isolates is a critical function of clinical microbiology laboratories. This study evaluated the accuracy and turnaround time for identification and susceptibility testing of Gram-negative bacilli inoculated directly from positive blood cultures into the Vitekr 2 system. Direct inoculation was compared to conventional methods; which included biochemical tests; commercial identification systems and disc diffusion susceptibility testing. Two hundred and ninety-one of 327 isolates (89) were correctly identified to at least genus level by the direct Vitekr method. Susceptibility test results were compared for 3;925 organism antibiotic combinations. The overall rate of categorical agreement of direct and conventional antimicrobial susceptibility testing was 92with less than 3very major and major errors combined. The mean turnaround time for identification and susceptibility testing was 7.5 hours (SD 3.0 hours) compared to a mean of 32.3 hours (SD 14.7 hours) for the conventional method. These results suggest that direct inoculation of the Vitekr 2 system from blood cultures provides accurate; reliable identification and antimicrobial susceptibility results for the majority of commonly occurring Gram-negative pathogens; while the significantly reduced turnaround time should benefit patients and permit earlier rationalisation of antibiotic therapy; with a reduction in the use of broad spectrum antibiotics. A suggested protocol for routine use is included


Asunto(s)
Medios de Cultivo , Bacterias Gramnegativas , Pruebas de Sensibilidad Microbiana , Reproducibilidad de los Resultados , Tiempo
16.
Int J Tuberc Lung Dis ; 13(11): 1373-9, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19861009

RESUMEN

OBJECTIVE: To evaluate the diagnostic yield and time to diagnosis of fine-needle aspiration biopsy (FNAB) vs. routine respiratory specimens collected from children with a palpable peripheral lymph node mass and symptoms suspicious of tuberculosis (TB). DESIGN: We performed a retrospective review of laboratory records at Tygerberg Hospital over a 4-year period from January 2003 to December 2006. All children (aged <13 years) in whom an FNAB and other mycobacterial specimens were collected as part of their diagnostic workup were included. RESULTS: In 95 children, the following specimens were collected: FNAB (n = 95), gastric aspirates (n = 142), other respiratory specimens (n = 36), non-respiratory specimens (n = 26). Mycobacterial disease was diagnosed in 70 (73.7%) patients. Children without respiratory specimens (n = 6) and/or with Mycobacterium bovis bacille Calmette-Guérin disease (n = 15) were excluded from comparative analysis. In the remainder, FNAB was positive in 45/74 (60.8%) vs. any respiratory specimen in 29/74 (39.2%, P < 0.001). The mean time to bacteriological diagnosis with FNAB was 7.1 days (95%CI 4.2-10.1) compared to 22.5 days (95%CI 15.8-29.1) for any respiratory specimen. CONCLUSION: FNAB is a simple, rapid and effective modality for achieving confirmation of mycobacterial disease in paediatric TB suspects with a palpable peripheral lymph node mass.


Asunto(s)
Técnicas Bacteriológicas , Biopsia con Aguja Fina , Mycobacterium/aislamiento & purificación , Tuberculosis Ganglionar/diagnóstico , Tuberculosis/diagnóstico , Niño , Preescolar , Femenino , Contenido Digestivo/microbiología , Humanos , Lactante , Masculino , Palpación , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Esputo/microbiología , Factores de Tiempo , Tuberculosis/microbiología , Tuberculosis Ganglionar/microbiología
17.
Artículo en Inglés | AIM (África) | ID: biblio-1270612

RESUMEN

Retrospective antibiotic surveillance data of selected invasive pathogens isolated from blood and cerebrospinal fluid at public sector hospitals in South Africa in 2007 are presented. Antimicrobial susceptibilities were determined according to the 2007 Clinical and Laboratory Standards Institute criteria. Klebsiella pneumoniae remains a highly resistant pathogen; with approximately half of all strains producing extended-spectrum beta-lactamases. All laboratories reported considerable resistance among Acinetobacter spp. Approximately 50-60of Staphylococcus aureus isolates from blood were resistant to cloxacillin. Among Streptococcus pneumoniae isolates from blood and cerebrospinal intermediate resistance to penicillin. Resistance to ceftriaxone in S. pneumoniae was rare


Asunto(s)
Antiinfecciosos , Resistencia a Medicamentos , Enterobacteriaceae , Hospitales , Staphylococcus aureus
19.
J Thromb Haemost ; 3(5): 991-1000, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15869596

RESUMEN

BACKGROUND: The development of inhibitors in hemophiliacs is a severe complication of factor VIII (FVIII) replacement therapy and is a process driven by FVIII specific T helper cells. OBJECTIVES: To finely map T cell epitopes within the whole FVIII protein in order to investigate the possibility of engineering FVIII variants with reduced propensity for inhibitor development. PATIENTS AND METHODS: T cell lines were generated from five patients with severe hemophilia who had developed inhibitors, and were screened for T cell proliferation against pools of overlapping peptides spanning the entire B domain deleted (BDD) FVIII sequence. Positive peptide pools were decoded by screening individual peptides against the T cell lines. Positive peptides, and mutants thereof, were tested for their ability to bind major histocompatibility complex (MHC) Class II and stimulate T cell proliferation in a panel of healthy donors. The activities of the corresponding mutant proteins were assessed via chromogenic assay. RESULTS: One peptide, spanning FVIII amino acids 2098-2112, elicited a vigorous response from one hemophiliac donor, induced strong T cell responses in the panel of healthy donors and bound to a number of HLA-DR alleles. Mutations were made in this peptide that removed its ability to stimulate T cells of healthy donors and to bind to MHC Class II while retaining full activity when incorporated into a mutant BDD-FVIII protein. CONCLUSIONS: Fine T cell epitope mapping of the entire FVIII protein is feasible, although challenging, and this knowledge may be used to create FVIII variants which potentially have reduced immunogenicity.


Asunto(s)
Linfocitos T CD4-Positivos/química , Mapeo Epitopo , Factor VIII/química , Alelos , Secuencia de Aminoácidos , Proliferación Celular , Clonación Molecular , Epítopos/química , Antígenos HLA-DR/inmunología , Hemofilia A/sangre , Hemofilia A/inmunología , Antígenos de Histocompatibilidad Clase II/química , Humanos , Concentración 50 Inhibidora , Iones , Activación de Linfocitos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mutación , Péptidos/química , Unión Proteica , Ingeniería de Proteínas , Estructura Terciaria de Proteína , Linfocitos T/inmunología , Factores de Tiempo
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