RESUMEN
INTRODUCTION: In parallel with a tremendous increase in medical PhD enrolments, concerns have risen about PhD candidates' poor well-being, increasing attrition rates for PhD programmes, and, eventually, a decline in clinician-scientists. According to the Self-Determination Theory, autonomous motivation is strongly linked to positive aspects of well-being and other positive outcomes such as study completion and success. In this way, motivation has a pivotal role in successful completion of medical doctoral programmes. In this study we explored factors affecting motivation during the PhD journey and aimed to contribute to engaging doctoral education environments, and, eventually, a sustainable clinician-scientist workforce. METHODS: This constructivist qualitative interview study was conducted among ten medical PhD candidates in the final phase of their PhD. We used timeline assisted interviews to identify meaningful experiences throughout their PhD journey. Thematic analyses as an iterative process resulted in overarching themes. RESULTS: We identified six themes influencing autonomous and controlled motivation along the challenging PhD journey: (1) Initial motivation to start a PhD matters; (2) Autonomy as a matter of the right dose at the right time; (3) PhD as proof of competence and/or learning trajectory?; (4) It takes two to tango; (5) Peers can make or break your PhD; (6) Strategies to stay or get back on track. CONCLUSION: This study revealed factors that contribute positively and/or negatively to autonomous and controlled motivation. Some factors impacted motivation differently depending on the PhD phase and individual strategies. Additionally, some factors could coincide and change from positive to negative and vice versa, showing that a successful journey cannot simply be reduced to an absence of negative experiences.
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Educación de Postgrado en Medicina , Motivación , Humanos , Aprendizaje , Investigación Cualitativa , Autonomía PersonalRESUMEN
OBJECTIVES: Postgraduate trainee selection is a high-stakes process. While many studies focused on selection methods and psychometrics, little is known about the influence of selectors' personal values and beliefs in the judgment and decision-making process. A better understanding of these factors is vital since selectors determine the future workforce. METHODS: We interviewed programme directors (PDs) from 11 specialties in one University Hospital. Thematic analysis was conducted with a combined approach of generic and in-vivo coding. RESULTS: PDs value excellence, 'fit' and personal characteristics. The content of these values are subject to personal interpretation and differ between PDs. PDs use various 'proxies' as alternative indicators of performance. They consider intuition, teamwork and autonomy important in judgement and decision-making. PDs find selection challenging and feel great accountability towards candidates and society. CONCLUSIONS: Selectors criteria of judgement- and decision-making often remain implicit and focus on prior achievements and 'fit' with the current trainee-pool, possibly compromising the workforce's diversity. Implicit 'proxies' and intuitive decision-making may be an unwitting source of judgemental bias. 'Making the implicit explicit', by increasing awareness of personal values and beliefs and structuring the selection interview, may improve the quality of trainee selection.
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Internado y Residencia , Humanos , Juicio , Psicometría , Investigación CualitativaRESUMEN
Physicians need to stay up-to-date with new developments in their field of expertise. This expectation has been made explicit by competency-based educational outcomes in the domain of scholar in the Dutch blueprint. There is a great diversity in teaching methods that aim to achieve a better understanding of scientific knowledge. Applying a constructivist approach to learning in acquiring research competencies we wonder how a research-intensive course is evaluated early in the curriculum and what learning gain students perceive. In a collaborative research-intensive course, the class of 300s-year students rated the quality of 150 preselected randomized controlled trials (RCT) using JAMA Users' Guides, and the pharmaceutical advertisements in which they were referenced. Each student rated two RCTs. Data were analyzed to answer a relevant research question. After the course students completed an evaluation survey. We did this in five consecutive years to capture student experience in relation to fostering a scientific mindset (n = 1,500). In addition we studied outcome of this scientific mindset as scientific output (publications) in journals. Survey data indicate that it is feasible to successfully implement a research-intensive course based on a large cohort using a constructivist paradigm early in the curriculum. Students consider it challenging and report high learning gain in several domains. Aggregated data have even led to four publications in journals. Implementing an active learning research experience early in the curriculum can foster student attitudes, provided the level of difficulty correctly matches the learners' prior knowledge. Further research is required to determine how to improve these active research curricula to maximize impact on learners.
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Competition between background microflora and microbial pathogens raises questions about the application of predictive microbiology in situ, i.e., in non-sterile naturally contaminated foods. In this article, we present a review of the models developed in predictive microbiology to describe interactions between microflora in foods, with a special focus on two approaches: one based on the Jameson effect (simultaneous deceleration of all microbial populations) and one based on the Lotka-Volterra competition model. As an illustration of the potential of these models, we propose various modeling examples in estimation and in prediction of microbial growth curves, all related to the behavior of Listeria monocytogenes with lactic acid bacteria in three pork meat products (fresh pork meat and two types of diced bacon).
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Microbiología de Alimentos/métodos , Lactobacillus/crecimiento & desarrollo , Listeria monocytogenes/crecimiento & desarrollo , Productos de la Carne/microbiología , Modelos Biológicos , Animales , Recuento de Colonia Microbiana , PorcinosRESUMEN
BACKGROUND: Most infants born through meconium-stained amniotic fluid (MSAF) are observed clinically for 24 h postnatally. Only 5% of infants born through MSAF develop the meconium aspiration syndrome (MAS), a serious condition requiring medical intervention. OBJECTIVE: To evaluate the value of 24-h postnatal observation of infants born through MSAF. METHODS: A cohort of 394 term neonates born through MSAF was studied. Data were collected on Apgar scores, the development of MAS and other perinatal factors. RESULTS: Nineteen of the 394 (4.8%) infants born through MSAF developed MAS. 298 (76%) infants had a 5-minute Apgar score (5'AS) of >or=9. In this group the number of infants developing MAS (1; 0.3%) was significantly lower compared with the 5'AS Asunto(s)
Líquido Amniótico
, Síndrome de Aspiración de Meconio/epidemiología
, Meconio
, Alta del Paciente
, Atención Perinatal/métodos
, Puntaje de Apgar
, Estudios de Cohortes
, Femenino
, Humanos
, Recién Nacido
, Masculino
, Síndrome de Aspiración de Meconio/diagnóstico
, Países Bajos
, Embarazo
RESUMEN
One in every 7 pregnancies ends with meconium-stained amniotic fluid and approximately 5% of these infants develop the meconium aspiration syndrome (MAS). MAS is a severe disease of the (mainly) term neonate, characterized by respiratory distress, pulmonary inflammation, persistent pulmonary hypertension and chronic hypoxia. The pathophysiology of MAS is multifactorial and complex. In this article, we discuss the mechanical and chemical effects of meconium on a newborn's airway, meconium-induced inflammation, mediated by proinflammatory cytokines and chemokines, the complement system and the proinflammatory enzyme phospholipase A2. Furthermore, we focus on MAS-related apoptotic cell death, causing severe acute lung injury due to damage and detachment of lung airway and alveolar cells. Finally, risk factors for MAS development to identify those newborns that develop MAS and those who do not are discussed.
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Síndrome de Aspiración de Meconio/etiología , Meconio , Apoptosis , Quimiocinas/fisiología , Citocinas/fisiología , Humanos , Recién Nacido , Pulmón/embriología , Pulmón/patología , Síndrome de Aspiración de Meconio/patología , Fosfolipasas A2/fisiología , Factores de RiesgoRESUMEN
AIM: Evaluation of the agreement between axillary temperature measurements and rectal temperature measurements in neonates. METHODS: Rectal and axillary body temperatures were simultaneously measured for 3 min in 33 neonates (gestational age 25-42 weeks, weight 840-4,005 g). Two investigators performed paired measurements, one in each neonate. A single type of thermometer was used in this study: one thermometer for each rectal and another thermometer for each axillary measurement. The Bland-Altman method was used (95% 'limits of agreement': mean +/- 2 SD) to determine the level of agreement between axillary and rectal measurements. RESULTS: The axillary temperature was significantly lower than the rectal temperature (mean +/- SD 0.27 +/- 0.20 degrees C, p < 0.05). The '95% limits of agreement' ranged from -0.13 to +0.67 degrees C. Increasing postnatal age (days) showed a significant increase in temperature difference (rectal minus axillary; r = 0.54; p < 0.05). CONCLUSIONS: The mean difference between axillary and rectal temperature shows a wide variation. Axillary temperature measurements cannot be used interchangeably with rectal measurements in neonates.
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Axila/fisiología , Temperatura Corporal/fisiología , Recién Nacido/fisiología , Recien Nacido Prematuro/fisiología , Recto/fisiología , Humanos , Reproducibilidad de los Resultados , TermómetrosRESUMEN
OBJECTIVE: To investigate secretory phospholipase A(2) (sPLA(2)) activity in neonatal sepsis. STUDY DESIGN: Plasma sPLA(2) activity, C-reactive protein (CRP) concentration, leukocyte count and immature/total neutrophil (I/T) ratio were assessed in a group of 156 infants admitted for neonatal intensive care, who were classified as documented sepsis (n=24), suspected infection (n=77) and controls (n=55). Interleukin-6 (IL-6) concentrations were assessed in a subgroup (n=29). RESULT: sPLA(2) activity, CRP concentration and I/T ratio were higher in sepsis than in suspected infection or control groups. sPLA(2) activity advanced with increasing CRP, I/T ratio and IL-6 was highest in infants with respiratory distress syndrome (RDS). Compared to CRP, sPLA(2) had equal sensitivity and lower specificity. Compared to I/T ratio, sensitivity and specificity of sPLA(2) were higher. CONCLUSION: Plasma sPLA(2) activity is increased in neonatal sepsis and highest in infants with RDS. Further studies should assess the potential of sPLA(2) inhibition in neonatal sepsis.
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Enfermedades del Prematuro/diagnóstico , Enfermedades del Prematuro/enzimología , Fosfolipasas A2 Secretoras/sangre , Sepsis/diagnóstico , Sepsis/enzimología , Proteína C-Reactiva/metabolismo , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/sangre , Interleucina-6/sangre , Recuento de Leucocitos , Masculino , Neutrófilos , Valor Predictivo de las Pruebas , Sepsis/sangreRESUMEN
Three male newborns, born at 30 weeks, 36 weeks and at term, respectively, developed serious complications related to umbilical venous catheters. The first patient had persistent bacteraemia due to a cardiac thrombus. He recovered after treatment. In the second patient, the umbilical venous catheter was placed in the pericardial sac, causing accumulation of parenteral nutrition and fatal cardiac tamponade. In the third patient, the umbilical catheter was positioned in the liver, leading to extravasation of parenteral nutrition in the liver and peritoneal cavity. At follow-up, he had developed an atrial septum defect, hypotonia and developmental retardation. Umbilical venous catheterisation has been used in neonatal intensive care units for more than 50 years to allow continuous infusion of medication, fluids and nutrition. However, the use of umbilical venous catheters can be associated with severe infectious, thrombotic and traumatic complications. Therefore, umbilical venous catheterisation requires a critical assessment of the need, alternatives and possible complications.
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Bacteriemia/etiología , Taponamiento Cardíaco/etiología , Catéteres de Permanencia/efectos adversos , Derrame Pericárdico/etiología , Venas Umbilicales , Trombosis de la Vena/etiología , Resultado Fatal , Humanos , Recién Nacido , Masculino , Factores de Riesgo , SeguridadRESUMEN
AIM: To investigate Listeria monocytogenes contamination and behaviour in naturally contaminated French cold-smoked salmon (CSS). METHOD AND RESULTS: Between 2001 and 2004, L. monocytogenes was detected in 104 of 1010 CSS packs, produced by nine French plants, with different prevalence (from 0% to 41%). The initial contamination, measured with a sensitive filtration method, was low (92% of contaminated products below 1 CFU g(-1)) and growth was limited. CONCLUSION: Growth was consistent with results of a predictive model including microbial competition. SIGNIFICANCE AND IMPACT OF THE STUDY: To be included in a quantitative risk assessment.
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Microbiología de Alimentos , Conservación de Alimentos , Listeria monocytogenes/crecimiento & desarrollo , Listeria monocytogenes/aislamiento & purificación , Salmón/microbiología , Animales , Frío , Recuento de Colonia Microbiana , Embalaje de Alimentos , Medición de RiesgoRESUMEN
Salting and smoking are ancient processes for fish preservation. The effects of salt and phenolic smoke compounds on the growth rate of L. monocytogenes in cold-smoked salmon were investigated through physico-chemical analyses, challenge tests on surface of cold-smoked salmon at 4 degrees C and 8 degrees C, and a survey of the literature. Estimated growth rates were compared to predictions of existing secondary models, taking into account the effects of temperature, water phase salt content, phenolic content, and additional factors (e.g. pH, lactate, dissolved CO2). The secondary model proposed by Devlieghere et al. [Devlieghere, F., Geeraerd, A.H., Versyck, K.J., Vandewaetere, B., van Impe, J., Debevere, J., 2001. Growth of Listeria monocytogenes in modified atmosphere packed cooked meat products: a predictive model. Food Microbiology 18, 53-66.] and modified by Giménez and Dalgaard [Giménez, B., Dalgaard, P., 2004. Modelling and predicting the simultaneous growth of Listeria monocytogenes and spoilage micro-organisms in cold-smoked salmon. Journal of Applied Microbiology 96, 96-109.] appears appropriate. However, further research is needed to understand all effects affecting growth of L. monocytogenes in cold-smoked salmon and to obtain fully validated predictive models for use in quantitative risk assessment.
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Manipulación de Alimentos/métodos , Conservación de Alimentos/métodos , Listeria monocytogenes/crecimiento & desarrollo , Salmón/microbiología , Alimentos Marinos/microbiología , Animales , Seguridad de Productos para el Consumidor , Embalaje de Alimentos/métodos , Humanos , Concentración de Iones de Hidrógeno , Oxígeno/metabolismo , Fenoles/farmacología , Valor Predictivo de las Pruebas , Medición de Riesgo , Cloruro de Sodio/farmacología , TemperaturaAsunto(s)
Antidepresivos de Segunda Generación/efectos adversos , Ciclohexanoles/efectos adversos , Síndrome de Abstinencia Neonatal/diagnóstico , Antidepresivos de Segunda Generación/administración & dosificación , Ciclohexanoles/administración & dosificación , Femenino , Humanos , Recién Nacido , Embarazo , Complicaciones del Embarazo/tratamiento farmacológico , Clorhidrato de VenlafaxinaRESUMEN
The quantitative risk assessment (QRA) approach recommended by the Codex Alimentarius Commission was used to assess the risk of human salmonellosis from the consumption of 'cordon bleu', a specific turkey product, in collective catering establishments (CCEs) of a French department. The complete process was modeled and simulated, from the initial storage in the CCE freezer to the consumption, using a Monte Carlo simulation software. Data concerning the prevalence of contaminated 'cordon bleu', the level of contamination of Salmonella, the cooking and storage process were collected from 21 CCEs and 8 retailers of 'cordon bleu' in the selected department. Thermal inactivation kinetics for Salmonella were established to estimate the effect of heat treatment on the concentration in the product and to calculate the dose that could be ingested by the consumer. The Beta-Poisson dose-response model of Rose and Gerba [Water Science and Technology 24 (1991) 29] with the specific parameters for Salmonella was used to estimate the probability of infection related to the ingestion of a particular dose and a factor was applied to estimate the probability of illness from ingestion. The individual risk of salmonellosis, the risk of outbreak and the number of cases were calculated using Monte Carlo simulation method. The risk of salmonellosis was close to zero when the 'cordons bleus' were cooked in the oven. Therefore, the risk was calculated for the fryer cooking since the insufficient cooking time observed was, sometimes, at the origin of low temperatures (37-89 degrees C). The influence of both the initial concentration of Salmonella in the product and the heat storage before consumption on the final risk was studied. For a high initial concentration of Salmonella in the product, when the 'cordons bleus' are fryer cooked, the average risk of salmonellosis was equal to 3.95 x 10(-3) without storage before consumption and 2.8 x 10(-4) if the product is consumed after storage. This paper presents the results of the QRA and discusses risk management options to minimize the risk of salmonellosis.
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Culinaria , Contaminación de Alimentos , Productos de la Carne/microbiología , Medición de Riesgo , Salmonella/crecimiento & desarrollo , Animales , Seguridad de Productos para el Consumidor , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Humanos , Modelos Biológicos , Método de Montecarlo , Intoxicación Alimentaria por Salmonella/etiología , Intoxicación Alimentaria por Salmonella/microbiología , Intoxicación Alimentaria por Salmonella/transmisión , PavosRESUMEN
UNLABELLED: Atelectasis, a major contributor to pulmonary dysfunction in meconium aspiration syndrome (MAS), is produced by bronchiolar obstruction and surfactant inactivation. It has been shown that substances in meconium, e.g. fatty acids, inhibit surfactant activity. However, the role of the enzyme phospholipase A2 (PLA2), which hydrolyses surfactant in adult respiratory distress syndrome (ARDS), has not yet been studied. Our objective was to investigate whether PLA2 is present in meconium and inhibits pulmonary surfactant activity in vitro. Therefore, the presence of PLA2 activity in meconium, collected from 10 newborns, was measured by the formation of lysophosphatidylcholine after incubation of meconium with radioactively labelled dipalmitoylphosphatidylcholine. Meconium was fractionated by Sephadex G-100 column chromatography and the fractions were assayed for PLA2 activity. Also, their effect on the surface tension of surfactant (Curosurf) was measured using a pulsating bubble surfactometer (PBS). PLA2 activity was present in all meconium samples. Addition of meconium to surfactant significantly increased surface tension (mean +/- SD: 1.7 +/- 1.6 mN/m to 24.3 +/- 6.7 mN/m, p = 0.0001) and only the addition of the PLA2 containing fraction from meconium to surfactant also significantly increased surface tension (mean 1.7 +/- 1.6 mN/m to 19.0 +/- 3.58 mN/m, p < 0.0001). CONCLUSION: PLA2 is present in meconium and inhibits the activity of pulmonary surfactant in vitro. Therefore, PLA2 in meconium may contribute to surfactant inactivation and alveolar atelectasis in MAS.
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Productos Biológicos , Meconio/enzimología , Fosfolipasas A/análisis , Fosfolipasas A/fisiología , Fosfolípidos , Surfactantes Pulmonares/fisiología , Cromatografía en Gel , Humanos , Técnicas In Vitro , Recién Nacido , Fosfolipasas A2 , Tensión SuperficialRESUMEN
BACKGROUND: Prooxidant activity of non-protein-bound iron (NPBI) is an important contributor to reactive oxygen species-induced injury after the resuscitation of critically ill patients. Plasma NPBI occurs in critically ill adults, children, and newborn babies, who often require resuscitation. The ability of the resuscitation fluids to bind iron and lower the patients' NPBI levels in vitro has not previously been studied. STUDY DESIGN AND METHODS: In an in vitro model, highly iron-saturated cord blood plasma from 10 preterm and 10 term babies was mixed with FFP, pasteurized plasma protein solution, and 0.9-percent saline. Plasma from 10 healthy adult volunteers was used as a control. Before and after the mixing with any resuscitation fluid, NPBI levels and ceruloplasmin iron-oxidizing and transferrin iron-binding antioxidant capacities were measured. RESULTS: After the in vitro mixing with FFP, the incidence and concentration of NPBI were markedly decreased and the iron-binding antioxidant capacity was increased in the plasma of the preterm and term babies. Being mixed with pasteurized plasma protein solution and 0.9-percent saline did not influence the iron-binding antioxidant capacity of newborn babies' plasma. In the control plasma, results were not changed after the mixing with any resuscitation fluid. In every group, the iron-oxidizing antioxidant capacity was not changed after the mixing with any fluid. CONCLUSION: Iron-induced oxidative tissue damage may be influenced by resuscitation fluids. In the ongoing debate over the choice of crystalloid or colloid resuscitation fluids, the influence of each fluid on the patient's antioxidant capacity warrants more attention.
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Antioxidantes/farmacología , Transfusión Sanguínea , Hierro/sangre , Resucitación , Adulto , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro/sangre , Hierro/metabolismo , Oxidación-Reducción , Embarazo , Unión ProteicaRESUMEN
OBJECTIVE: To evaluate a less invasive management strategy for pregnant women with neonatal alloimmune thrombocytopenia without a history of intracranial haemorrhage. DESIGN: Retrospective and descriptive. METHOD: In Leiden University Medical Centre, the Netherlands, in the period 1994-August 1999, 31 women with 32 pregnancies were treated. Six women had a history of a sibling with thrombocytopenia and intracranial haemorrhage and 26 a history of a sibling with (severe) thrombocytopenia without haemorrhage. Treatment options consisted of weekly administered intravenous immunoglobulin (ivIG) to the mother without diagnostic cordocentesis, cordocentesis with foetal blood sampling and intrauterine platelet transfusions to the fetus. In the group without history of intracranial haemorrhage fetal blood sampling and platelet transfusion were gradually abandoned as much as possible. RESULTS: In the children of the treated pregnant women there were no instances of intracranial haemorrhage. In addition, the platelet count in cord blood was higher, compared with patients treated before 1994 and with literature data. CONCLUSION: A less invasive management strategy in case of a history without intracranial haemorrhage seems justified based on results in our population. Administration of ivIG without diagnostic cordocentesis, however, results in a lost opportunity to verify the indication and the effectiveness of treatment.
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Enfermedades Fetales/tratamiento farmacológico , Inmunoglobulinas Intravenosas/uso terapéutico , Enfermedades del Recién Nacido/prevención & control , Hemorragias Intracraneales/prevención & control , Complicaciones Hematológicas del Embarazo/prevención & control , Atención Prenatal/métodos , Trombocitopenia/tratamiento farmacológico , Contraindicaciones , Femenino , Enfermedades Fetales/diagnóstico , Enfermedades Fetales/inmunología , Transfusión Fetomaterna/inmunología , Fetoscopía , Humanos , Recién Nacido , Enfermedades del Recién Nacido/inmunología , Hemorragias Intracraneales/inmunología , Masculino , Transfusión de Plaquetas , Embarazo , Complicaciones Hematológicas del Embarazo/inmunología , Diagnóstico Prenatal/métodos , Estudios Retrospectivos , Análisis de Supervivencia , Trombocitopenia/inmunología , Resultado del TratamientoAsunto(s)
Monitoreo Intraoperatorio/normas , Austria , Alemania , Humanos , Países Bajos , Bloqueo NeuromuscularRESUMEN
Acinetobacter junii caused sepsis in six preterm infants in our neonatal unit within 48 h. Each infant with clinical signs of systemic infection and activation of the acute phase response had two positive blood cultures with Acinetobacter junii. The sudden onset, the short duration of the outbreak and the fact that none of the infants were colonized by A. junii suggested a common source of A. junii administered directly into the blood. The only feature shared by all six affected newborns was an intravenous fat emulsion (Intralipid 10%), which was shown to be an excellent growth medium for A. junii. Sepsis did not occur in four infants with 20% fat emulsion or amino acids only. Vaminolact did not support growth of the outbreak strain. The immediate source of the outbreak could not be identified: samples of the actual feeds given were not available for investigation, but A. junii was not isolated from parenteral solutions with identical batch numbers used in the septic infants. We conclude that Acinetobacter junii can cause a life-threatening infection in preterm neonates. Contaminated intravenous fat emulsion is implicated as a possible source of the infection. As a part of rigid infection control, intravenous feedings should be prepared under aseptic conditions.
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Infecciones por Acinetobacter/complicaciones , Bacteriemia/microbiología , Infecciones por Acinetobacter/prevención & control , Bacteriemia/prevención & control , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal , Masculino , Factores de TiempoRESUMEN
Four previously healthy children, two boys aged 5 and one boy and one girl aged 4 more or less acutely developed a stumbling gait. The causes varied from benign such as postviral acute cerebellar ataxia and benign paroxysmal vertigo to potentially life-threatening such as intoxication with benzodiazepines and medulloblastoma. Treatment led to complete or partial recovery. (Sub)acute balance disorders in previously healthy children can be due to cerebellar ataxia, vestibular disorders and abnormal proprioception. Ancillary investigations are warranted in case of gradually developing ataxia, accompanying neurological deficits, suspicion of intoxication, recurrent or familial ataxia, no spontaneous remission or even progression. In children with an isolated cerebellar ataxia without these features, ancillary investigations may be avoided, although in such cases careful follow-up remains necessary.