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STUDY DESIGN: Prospective, randomized, controlled parallel group trial with single-blinded data analysis. OBJECTIVES: To determine the safety and efficacy of higher (20 ml kg(-1) ideal body weight (IBW)) vs standard (10 ml kg(-1) IBW) tidal volumes (Vt) for patients with sub-acute traumatic tetraplegia during ventilator weaning using a 14-day (minimum) weaning protocol. SETTING: United States regional spinal cord injury treatment center. METHODS: Thirty-three ventilator requiring inpatients were randomized to either the higher (Group 1) or the standard (Group 2) Vt protocol. Initially, all patients were ventilated at 10 ml kg(-1) IBW Vt and 5 cm H(2)O [corrected] of PEEP for 72 h. For Group 1, Vt was raised 100 ml kg(-1) until reaching target Vt of 20 ml kg(-1) IBW. Group 2 was maintained at Vt of 10 ml kg(-1) IBW. Plateau pressures were kept at or below 30 cm H(2)O. [corrected]. Safety outcomes included incidence of adverse events. RESULTS: Because of smaller than expected enrollment, evaluation of efficacy was not possible. Therefore, we report the safety outcomes of 33 study participants. The 16 patients in Group 1 and 17 patients in Group 2 were demographically similar at baseline, except for age. The average age was 39.3 years in Group 1 and 27.2 years in Group 2, (P=0.002). There was no difference in median days to wean: 14.5 days in Group 1 and 14 days in Group 2. The incidence of adverse pulmonary events was similar between groups. CONCLUSION: Higher tidal volumes can be safely utilized during weaning of patients with tetraplegia from mechanical ventilation using a 14-day weaning protocol.
Assuntos
Traumatismos da Medula Espinal/complicações , Volume de Ventilação Pulmonar/fisiologia , Desmame do Respirador/métodos , Adulto , Vértebras Cervicais/lesões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismos da Medula Espinal/fisiopatologiaRESUMO
The letter to the editor plays a dual role in the literature. It serves a corrective critical function but also has the capacity to spread and share knowledge. We sought to identify the role and theme of letters to the editor published in four leading otorhinolaryngology journals, to elicit how well this form of communication is being utilised. All letters to the editor published in; Clinical Otolaryngology, The Laryngoscope, The European Archives of Otorhinolarygnology and The Journal of Laryngology and Otology, for the year 2012, were examined and the individual journal guidelines for submission of letters were noted. Seventeen different countries produced a total of 92 letters for the year 2012. The majority of letters originated from Otolaryngology/Head and Neck departments (78 %). Clinical Otolaryngology contributed to 58 % of total letters, of which 55 % were unrelated to original journal material (n = 29). The Laryngoscope published letters solely in response to original journal material. The Journal of Laryngology and Otology was the only journal to index letters with their corresponding article. More letters agreeing (49 %) than disagreeing (32 %) were published, with the remaining letters either clarifying or ignoring issues raised. Letters to the editor serve two main purposes; post-publication peer review and sharing experiences with fellow readers. Both are equally important in maintaining journals' high standards. Indexing needs to be improved otherwise valuable comment does not endure while the original manuscript's message lives on.
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Correspondência como Assunto , Políticas Editoriais , Otolaringologia , Publicações Periódicas como Assunto , HumanosRESUMO
OBJECTIVES: Medical research involving human subjects must follow ethical standards as outlined in the Declaration of Helsinki of the World Medical Association. The aim of this study was to assess the frequency of reporting of informed consent and regional ethical committee (REC) approval in all reports of trials published in the major European Otolaryngology journals. DESIGN: Review of all clinical research articles published online in the calendar year 2012. SETTING: Three leading European Otolaryngology journals. PARTICIPANTS: Clinical Otolaryngology, The Journal of Laryngology and Otology and The European Achieves of Oto-Rhino-Laryngology. MAIN OUTCOME MEASURES: Evaluate the incidence of reporting of REC approval and informed consent. RESULTS: Of the 767 articles reviewed, 401 met the inclusion criteria (manuscripts reporting human subjects, human tissue or identifiable personal data research which require ethical approval). 49.9% lacked a statement of REC approval and 42.9% lacked disclosure of informed consent. Articles that did not state REC approval were associated with not stating informed consent (P < 0.05). CONCLUSION: Articles that lack explicit statements of REC approval and informed consent are frequent and continue to be published in major otolaryngology journals.
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Pesquisa Biomédica/ética , Revelação , Comitês de Ética em Pesquisa , Consentimento Livre e Esclarecido , Otolaringologia , Publicações Periódicas como Assunto , HumanosRESUMO
OBJECTIVE: To explore alternative bibliometric markers to the well-established journal impact factor. The bibliometric evolution of a leading ENT journal over a six year period is discussed with critical analysis of a predetermined set of bibliometric alternatives to the journal impact factor. DESIGN: Retrospective review of the bibliometric performance of Clinical Otolaryngology over a six year period. RESULTS: The results of the study reveal that Clinical Otolaryngology has made steady bibliometric progress when the impact factor (IF) is considered with a gradual increase in impact factor from 1.098 in 2006 to a peak of 2.393 in 2011. Self-citation rates reported by the Journal Citation Report (JCR) demonstrated a significant decline during 2007 with a reported self-citation rate of 0%. The SCImago Journal Rank (SJR) database however recorded a self-citation rate of 67. Independent evaluation demonstrated a 56 self-citations during this period. The percentage of review articles published remained stable during the period in question. A lagged association between the number of review manuscripts and the IF failed to demonstrate any significant correlation (r = -0.19). Comparison between the IF and the Eigen factor (EF) as well as the SJR yielded negative correlation (r = -0.46) and (r = -0.35) respectively. The Article Influence score (AIS) and Source Normalised Impact per Paper (SNIP) were the only bibliometric alternatives to demonstrate a positive correlation when compared to the IF (r = 0.94) and (r = 0.66) respectively. CONCLUSIONS: The necessity of bibliometric markers cannot be called into question however the most widely employed of these, the journal impact factor has come under increased scrutiny of late. Despite some of the advantages offered by novel bibliometric markers, these do not necessarily compare favourably to the IF with regards to bibliometric performance. The only two markers to demonstrate a positive correlation when compared to the IF were the AI score and SNIP which would suggest that these are potential alternatives to the IF and have the added advantage that they are open access.
Assuntos
Bibliometria , Editoração , Fator de Impacto de Revistas , Otolaringologia , Estudos RetrospectivosRESUMO
Despite an increase in ENT postal questionnaires, the quality of their methodology has been questioned (Ramphul et al. in J Laryngol Otol 119:175-178, 1). This retrospective study examined whether quality and utility of such questionnaires published since 2005 has improved. Seventeen consultant postal questionnaires published between 2005 and 2012 were reviewed. Quality of questionnaires was assessed using a 30-point score based on compliance with 15 criteria previously established to evaluate postal questionnaire study-design (Ramphul et al. in J Laryngol Otol 119:175-178, 1). Citation rates were used as an indicator of utility. The specific comments made in each citing paper was reviewed providing information on whether questionnaire findings (a) had an impact on clinical practice, (b) were the citing comments positive, (c) negative or (d) non-specific. Recurrent methodological flaws were identified in all questionnaires. The average score assigned was 44 %, versus 32 % previously reported (Ramphul et al. in J Laryngol Otol 119:175-178, 1) (P < 0.01, Student's t test). The low citation rate demonstrates poor utility for postal questionnaires. Citations were general non-specific referencing with no clear indication that questionnaire findings positively impacted clinical practice. In conclusion, although the quality of ENT postal questionnaire has improved since the original study (Ramphul et al. in J Laryngol Otol 119:175-178, 1), important recurring methodological flaws still exist. The poor utility, based on low citation rates, also reflects the continued deficiencies in design quality. It is recommended that authors of questionnaire-based research should ensure that guidelines for questionnaire design are adhered in order to improve the validity of findings and hence impact on clinical practice.
Assuntos
Consultores , Otolaringologia , Serviços Postais , Inquéritos e Questionários/estatística & dados numéricos , Inquéritos e Questionários/normas , Humanos , Fator de Impacto de Revistas , Publicações Periódicas como Assunto , Controle de Qualidade , Estudos Retrospectivos , Revisão da Utilização de Recursos de SaúdeAssuntos
Dor de Orelha/diagnóstico , Dor de Orelha/etiologia , Otolaringologia , Seleção de Pacientes , Encaminhamento e Consulta , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Dor de Orelha/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
AIMS: Ascertain whether a demographic analysis of the archives of an annual national meeting head and neck section could reflect contemporary issues in our specialty and compare the results with available analysis from other ORL-HNS meetings. MATERIALS AND METHODS: A review of all accepted abstracts of Sylvester O'Halloran Symposium-H&N section, from 2005 to 2020. RESULTS: ORL-HNS was responsible for 77% of the accepted abstracts. Presentations on H&N Malignancy were predominantly from ORL-HNS (84%), while Thyroid presentations were divided with General Surgery (45%). Medical students have appeared in recent years and produced 4% of papers at the last meeting while more junior presenters are participating with an increasing female preponderance (ranging from 7 to 53%). The overall publication rate was 27%, where male authors had a rate of 28% and females 22%. Similar papers published subsequent to the relevant meeting were identified from other institutions in 40% of presentations. CONCLUSION: This review of presentations at a surgical meeting provides an insight into contemporary issues involving our specialty and lays down markers or challenges for organisers and presenters alike. Presentations on H&N Malignancy have become almost exclusively ORL-HNS, while Thyroid presentations are becoming more valorised to General Surgery and Facial Plastics with our colleagues in Plastic Surgery and Maxillofacial. Our publication rate of 27% is similar to other ORL-HNS meetings. Approximately 10% are published over 5 years after the meeting but presenters should endeavour to publish earlier as others may usurp publication in up to 40% of presentations.
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Medicina , Procedimentos de Cirurgia Plástica , Humanos , Masculino , FemininoRESUMO
We report that, to enable studies of their compositional, structural and electrical properties, freestanding individual nanoobjects can be selectively felled in a controllable way by the technique of low-current focused-ion-beam (FIB) milling with the ion beam at a chosen angle of incidence to the nanoobject. To demonstrate the suitability of the technique, we report results for zigzag/straight tungsten nanowires grown vertically on support substrates and then felled for characterization. We also describe a systematic investigation of the effect of the experimental geometry and parameters on the felling process and on the induced wire-bending phenomenon. The method of felling freestanding nanoobjects using FIB is an advantageous new technique enabling investigations of the properties of selected individual nanoobjects.
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Transtorno Conversivo/diagnóstico , Transtornos de Deglutição/diagnóstico , Doenças Faríngeas/diagnóstico , Terminologia como Assunto , Transtorno Conversivo/etiologia , Transtorno Conversivo/psicologia , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/psicologia , Diagnóstico Diferencial , Humanos , Doenças Faríngeas/etiologia , Doenças Faríngeas/psicologiaRESUMO
OBJECTIVES: Tonsillectomy has generated extensive comment on the internet, but this content has not been examined in a scientific manner. This study aimed to determine what the blogosphere has to say about adult tonsillectomy and to report whether this information can be used to improve post-surgical care. METHODS: The internet was searched to find personal blogs relating to tonsillectomy. A retrospective review of data collected on these blogs was carried out and the blogs were conceptually analysed by the authors. RESULTS: Fifty blogs were included. Seventy per cent of patients had read blogs prior to their procedure. The average pain score where available was 7.2. Complications occurred in 10 per cent of patients. Only 1 patient (2 per cent) regretted having a tonsillectomy. CONCLUSION: It is important for otolaryngologists to stay in tune with the blogosphere as this unregulated and easily accessible source of information is both friend and foe but will ultimately help in pre-operative counselling and post-operative management.
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Analgésicos/uso terapêutico , Blogging , Dor Pós-Operatória/tratamento farmacológico , Satisfação do Paciente , Complicações Pós-Operatórias , Tonsilectomia , Tonsilite/cirurgia , Adulto , Feminino , Humanos , Internet , Masculino , Medição da DorRESUMO
A 2-yr study was conducted to evaluate the effects of beef genotypes and feeding systems on performance, carcass traits, meat quality, and sensory attributes. A 2×2 factorial experiment was used to randomly allocate 60 steers in year 1 (YR1) and 44 steers in year 2 (YR2). The two beef genotypes evaluated were Red Angus (RA), and RA x Akaushi (AK) crossbreed. The steers were allotted to two finishing feeding systems: grazing, a multi-species forage mixture (GRASS) and feedlot finishing, conventional total mixed ration (GRAIN). All steers were slaughtered on the same day, at 26 and 18 mo of age (GRASS and GRAIN, respectively), and carcass data were collected 48 h postmortem. Growth and slaughter characteristics were significantly impacted by the finishing system (P < 0.01), with the best results presented by GRAIN. Beef genotype affected dressing percent (P < 0.01), ribeye area (P = 0.04), and marbling score (P = 0.01). The AK steers had a tendency (P = 0.09) for lower total gain; however, carcass quality scores were greater compared to RA. There was a genotype by system interaction for USDA yield grade (P < 0.01), where it was lower in GRASS compared to GRAIN in both genotypes, and no difference was observed between the two genotypes for any GRASS or GRAIN systems. There was no difference in meat quality or sensory attributes (P > 0.10) between the two genotypes, except that steaks from AK tended to be juicier than RA (P = 0.06). Thawing loss and color variables were impacted by the finishing system (P < 0.01). L* (lightness) and hue angle presented greater values while a* (redness), b* (yellowness), and chroma presented lower values in GRAIN compared to GRASS. Sensory attributes were scored better in GRAIN than GRASS beef (P < 0.01). There was a genotype by system interaction for flavor (P = 0.02), where beef from RA had a lower flavor rating in GRASS than in GRAIN, and no difference was observed for AK. Within each system, no difference was observed for flavor between RA and AK. Beef from steers in GRASS had greater (P < 0.01) WBSF than those from GRAIN. These results indicate that steers from GRAIN had superior performance and carcass merit and that AK enhanced these traits to a greater degree compared to RA. Furthermore, the beef finishing system had a marked impact on the steaks' sensory attributes and consumer acceptability. The favorable results for texture and juiciness in GRAIN, which likely impacted overall acceptability, may be related to high marbling.
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Interleukin 1 (IL-1) is a potent mediator of inflammatory and immunologic phenomena. In addition, IL-1 may be intimately involved in the regulation of hemostasis, since interaction of IL-1 with endothelial cells has been reported to induce tissue factor activity. We demonstrate that perturbation of the endothelial cell induces augmented IL-1 release. Human umbilical vein endothelial cells perturbed by treatment with lipopolysaccharide produced enhanced amounts of IL-1 activity. IL-1 activity from lipopolysaccharide-treated endothelial cell supernatants could be absorbed by an antibody to IL-1 coupled to Sepharose. Elaboration of IL-1 activity was dependent on the dose of lipopolysaccharide and occurred in a time-dependent manner. Addition of cycloheximide blocked generation of IL-1 activity. A physiological vessel wall perturbant, the coagulation enzyme thrombin, induced comparable amounts of IL-1 activity in endothelial cell cultures. This effect was specific for the enzyme, since active site-blocked thrombin and prothrombin had no effect on IL-1. In addition, IL-1-containing supernatants from thrombin-stimulated endothelial cells induced tissue factor procoagulant activity in fresh endothelial cell cultures. Thus, in contrast to the multiple, known inhibitory mechanisms that block thrombin procoagulant activity, these data suggest a circle of interaction in which thrombin induces endothelial cell elaboration of IL-1, a mediator of endothelial cell procoagulant activity. Endothelial cell production of IL-1 in response to perturbation allows these cells to play an integral role in the regulation of the inflammatory and coagulation systems.
Assuntos
Coagulação Sanguínea , Endotélio/fisiologia , Interleucina-1/biossíntese , Animais , Células Cultivadas , Humanos , Lipopolissacarídeos/farmacologia , Coelhos , Trombina/farmacologia , Veias Umbilicais/metabolismoRESUMO
BACKGROUND: The risk of death after tonsillectomy is extremely small, and is mostly caused by the direct or indirect effects of haemorrhage or anaesthetic complications. These complications include aspiration, accidental dislodgement of the tracheal tube (TT), and pneumothorax or pneumomediastinum. The Boyle-Davis mouth gag (BDG) is a device used to visualize the oropharynx and stabilize the TT during tonsillectomy. We postulate that a deployed BDG may influence the position of the TT, and potentially result in silent aspiration, accidental extubation, and unilateral pulmonary ventilation. This has not, to our knowledge, been evaluated before. The aim of this prospective, pilot study was to evaluate the displacement of the TT upon opening and closing the BDG, in an objective manner. METHODS: Patients undergoing tonsillectomy with/without adenoidectomy at a regional department underwent flexible bronchoscopy to evaluate the changes in position of the TT tip with the BDG in an open and closed position, relative to the position of the carina. RESULTS: Twenty-three patients were enrolled into the study. Deploying the BDG resulted in TT displacement in 96% of patients. The mean displacement was 9.5 mm (range -10 to +27 mm). CONCLUSIONS: We believe that this study raises concerns not previously highlighted, on how manipulating a BDG may influence the TT position. It may serve to explain additional mechanisms of potentially fatal anaesthetic complications such as TT dislodgement, unilateral ventilation, and pneumothorax, particularly in paediatric patients, after tonsillectomy.
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Intubação Intratraqueal/instrumentação , Tonsilectomia/instrumentação , Adolescente , Adulto , Anestesia Geral/métodos , Broncoscopia , Criança , Pré-Escolar , Feminino , Tecnologia de Fibra Óptica , Migração de Corpo Estranho/etiologia , Humanos , Intubação Intratraqueal/efeitos adversos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Tonsilectomia/efeitos adversos , Adulto JovemRESUMO
The Hirsch (h) index is an original and simple new bibliometric measure incorporating both quantity and quality. In this study, our aim was first to present characteristics of the statistical correlation between the h index and several standard bibliometric indicators and secondly we compared the h index between otolaryngologists from Europe and US. We used the Institute of Scientific Information (ISI) Web of Knowledge to identify citation reports from a random sample of influential editors from six otolaryngology journals: Journal of Laryngology and Otology (n = 21), Clinical Otolaryngology (n = 16), European Archives of Oto-Rhino-Laryngology (n = 49), The Laryngoscope (n = 66), Otolaryngology-Head and Neck Surgery (n = 15), and Archives of Otolaryngology-Head and Neck Surgery (n = 15). The following data were gathered: Number of publications (P), total citations received by P(C), total citations received by P without self-citations (Cs), average number of citations per publication (CPP), and Hirsch index (h). Statistical analysis was used to correlate the above data and we also compared the h index of European and North American editors. There were 182 randomly selected editors. We observed a good correlation between the h index and other standard bibliometric indicators. Using the non-parametric Mann-Whitney test, the median P between Europe and US was not statistically significant. However, the median C, CS and h were statistically significant. In conclusion, the h index is a simple yet powerful indicator as it combines productivity and impact. Overall, the US editorial panel have a higher h index.
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Autoria , Bibliometria , Comparação Transcultural , Fator de Impacto de Revistas , Otolaringologia/estatística & dados numéricos , Publicações Periódicas como Assunto , Editoração/estatística & dados numéricos , Europa (Continente) , Humanos , Estados UnidosRESUMO
The study of errors in medicine has proliferated since the publication of The Institute of Medicine Report 'TO ERR IS HUMAN' in 2000. Case nuances and process of care issues are valuable areas to explore if the goal is to provide the health care worker with the knowledge to avoid future errors. Meta-analysis and randomized controlled trials provide a large data base of evidence towards improvement and opportunities, but it is suggested that case reports can still provide valuable clinical information. The aim is to use the published literature to produce a series of rare harm case reports in E.N.T. The methods include systematic literature review. Journals searched in PUBMED were 60. Rare harm case obtained from the search were 5,322. Rare harm case reports not reported in any other form of evidence-based medicine were 40. Yes, the case report can be defended as it is an important pillar of evidence-based medicine.
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Medicina Baseada em Evidências , Erros Médicos , Registros Médicos Orientados a Problemas , Otolaringologia , Humanos , Erros Médicos/prevenção & controle , Metanálise como Assunto , Garantia da Qualidade dos Cuidados de Saúde , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: We investigated the hypothesis that a lymphocyte/white cell count ratio should be used as a diagnostic indicator of infectious mononucleosis. DESIGN: Retrospective study to compare lymphocyte counts and white blood cell counts, against the criterion standard, the mononucleosis spot test. SETTING: Department of Otolaryngology, Mater Misericordiae University Hospital, Dublin, Ireland. PARTICIPANTS: We reviewed 1000 patients who had Monospot assays, 500 positive and 500 negative. MAIN OUTCOME MEASURES: The lymphocyte counts and white blood cell ratio was calculated and compared with the monospot result to calculate the sensitivity and specificity at various ratios. RESULTS: The lymphocyte counts and white blood cell ratio was significantly different in the positive and negative monospot groups (P < 0.05). The mean lymphocyte counts and white blood cell ratio in the positive group was 0.49 and the mean lymphocyte to white cell count ratio in the monospot negative group was 0.29.A ratio of 0.35 had a specificity of 72% and a sensitivity of 84% for the detection of glandular fever. A higher ratio will give a greater specificity, but a lower sensitivity, and vice versa. CONCLUSIONS: The mean lymphocyte to white cell count ratio is not sufficient to diagnose or exclude infectious mononucleosis. Thus, this study does not confirm the conclusions of earlier studies.
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Testes Hematológicos/métodos , Mononucleose Infecciosa/diagnóstico , Contagem de Leucócitos , Feminino , Humanos , Mononucleose Infecciosa/sangue , Contagem de Linfócitos , Masculino , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
Large post intubation tracheal tears are usually detected intra-operatively due to unstable signs namely impaired ventilation and mediastinal emphysema and often require surgical management. Smaller tracheal tears are often missed during anaesthesia and recognized during the postoperative period. Conservative management should be considered in these latter cases.
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Doença Iatrogênica , Intubação Intratraqueal/efeitos adversos , Enfisema Mediastínico/etiologia , Traqueia/lesões , Adulto , Feminino , Humanos , Lacerações/diagnóstico por imagem , Enfisema Mediastínico/diagnóstico , Radiografia , Traqueia/diagnóstico por imagemRESUMO
BACKGROUND: Fungal otitis externa is prevalent in tropical and sub-tropical climates; however, over the past two decades, there has been a reported increase in the prevalence of otomycosis in paediatric patients from more temperate climates. This study aimed to review the children diagnosed with otomycosis at the University Hospital Limerick with reference to frequency, causative organism, predisposing factors and management. METHODS: A retrospective review was conducted of paediatric patients from 2001 to 2015. Patients with positive fungal ear swabs and a diagnosis of otomycosis were identified. RESULTS: Ninety-three patients were positive for candida (mean age, 5.8 years), 10 patients were positive for aspergillus (mean age, 9.1 years) and 1 patient had mixed fungal infection containing both fungi. There was a positive correlation between a diagnosis of otomycosis and prior treatment with topical fluoroquinolones (r = 0.8; p < 0.01). CONCLUSION: The incidence of otomycosis has been increasing since 2001, which correlates with an increase in the use of topical fluoroquinolones. Previous studies identify aspergillus as the commonest causative fungi; however, this study found that candida was the commonest isolated fungi in the paediatric population.
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Otomicose/epidemiologia , Antifúngicos/uso terapêutico , Aspergilose/diagnóstico , Aspergilose/tratamento farmacológico , Aspergilose/epidemiologia , Aspergilose/microbiologia , Candidíase/diagnóstico , Candidíase/tratamento farmacológico , Candidíase/epidemiologia , Candidíase/microbiologia , Criança , Pré-Escolar , Coinfecção/diagnóstico , Coinfecção/tratamento farmacológico , Coinfecção/epidemiologia , Coinfecção/microbiologia , Feminino , Humanos , Incidência , Irlanda/epidemiologia , Masculino , Otomicose/diagnóstico , Otomicose/tratamento farmacológico , Otomicose/microbiologia , Estudos RetrospectivosRESUMO
To assess interlaboratory variability in qualitative and quantitative cytomegalovirus (CMV) viral load (VL) testing, we distributed a panel of samples to 33 laboratories in the USA, Canada and Europe who performed testing using commercial reagents (n = 17) or laboratory-developed assays (n = 18). The panel included two negatives, seven samples constructed from purified CMV nucleocapsids in plasma (2.0-6.0 log(10) copies/mL) and three clinical plasma samples. Interlaboratory variation was observed in both actual (range, 2.0-4.0 log(10) copies/mL) and self-reported lower limits of detection (range, 1.0-4.0 log(10) copies/mL). Variation observed in reported results for individual samples ranged from 2.0 log(10) (minimum) to 4.3 log(10) (maximum)(.) Variation was greatest at low VLs. Assuming +/- 0.5 log(10) relative to the expected result represents an acceptable result, 57.6% of results fell within this range. Use of commercially available reagents and procedures was associated with less variability compared with laboratory-developed assays. Interlaboratory variability on replicate samples was significantly greater than intralaboratory variability (p < 0.0001). The significant interlaboratory variability in CMV VL observed may be impacting patient care and limiting interinstitutional comparisons. The creation of an international reference standard for CMV VL assay calibration would be an important step in quality improvement of this laboratory tool.