A case of EDTA-dependent pseudothrombocytopenia: simple recognition of an underdiagnosed and misleading phenomenon

1. BMC Clin Pathol. 2014 May 1;14:19. doi: 10.1186/1472-6890-14-19. eCollection 2014. A case of EDTA-dependent pseudothrombocytopenia: simple recognition of an underdiagnosed and misleading phenomenon. Nagler M, Keller P, Siegrist D, Alberio L. Author information: Department of Hematology and Central Hematology Laboratory, Inselspital University Hospital and University of Berne, CH-3010 Berne, Switzerland. BACKGROUND: EDTA-dependent pseudothrombocytopenia (EDTA-PTCP) is a common laboratory phenomenon with a prevalence ranging from 0.1-2% in hospitalized patients to 15-17% in outpatients evaluated for isolated thrombocytopenia. Despite its harmlessness, EDTA-PTCP frequently leads to time-consuming, costly and even invasive diagnostic investigations. EDTA-PTCP is often overlooked because blood smears are not evaluated visually in routine practice and histograms as well as warning flags of hematology analyzers are not interpreted correctly. Nonetheless, EDTA-PTCP may be diagnosed easily even by general practitioners without any experiences in blood film examinations. This is the first report illustrating the typical patterns of a platelet (PLT) and white blood cell (WBC) histograms of hematology analyzers. CASE PRESENTATION: A 37-year-old female patient of Caucasian origin was referred with suspected acute leukemia and the crew of the emergency unit arranged extensive investigations for work-up. However, examination of EDTA blood sample revealed atypical lymphocytes and an isolated thrombocytopenia together with typical patterns of WBC and PLT histograms: a serrated curve of the platelet histogram and a peculiar peak on the left side of the WBC histogram. EDTA-PTCP was confirmed by a normal platelet count when examining citrated blood. CONCLUSION: Awareness of typical PLT and WBC patterns may alert to the presence of EDTA-PTCP in routine laboratory practice helping to avoid unnecessary investigations and over-treatment. PMCID: PMC4012027 PMID: 24808761 [PubMed]

Inference in Ecology: The Sea Urchin Phenomenon in the Northwestern Atlantic

We have reviewed the considerable body of research into the sea urchin phenomenon responsible for the alternation between macroalgal beds and coralline barrens in the northwestern Atlantic. In doing so, we have identified problems with both the scientific approach and the interpretation of results. Over a period of approximately 20 years, explanations for the phenomenon invoked four separate scenarios, which changed mainly as a consequence of extraneous events rather than experimental testing. Our specific concerns are that results contrary to the keystone-predator paradigm for the American lobster were circumvented, system components of the various scenarios became accepted without testing, and modifications of some components appeared arbitrary. Our review illustrates dilemmas that, we suggest, have hindered ecological progress in general. We argue for a more rigorous experimental approach, based on sound natural-history observations and strong inference. Moreover, we believe that the scientific community needs to be cautious about allowing paradigms to become established without adequate scrutiny.

Localized Epidermal Cysts as a Radiation Recall Phenomenon in a Melanoma Patient Treated with Radiotherapy and the BRAF Inhibitor Vemurafenib

BRAF inhibitors are broadly used for metastatic melanoma with BRAF mutations. Their use results in various cutaneous side effects, such as the development of keratoacanthomas and squamous cell carcinomas. We report a patient with metastatic melanoma treated with vemurafenib who developed dozens of histologically confirmed epidermal cysts within 2 months after initiation of vemurafenib administration. The cystic lesions were observed only in the localized area where a large exophytic melanoma tumor mass had been previously irradiated. Localized epidermal cysts may constitute an unusual radiation recall reaction in patients treated with BRAF inhibitors.

Suicide tourism: a pilot study on the swiss phenomenon

While assisted suicide (AS) is strictly restricted in many countries, it is not clearly regulated by law in Switzerland. This imbalance leads to an influx of people —‘suicide tourists’—coming to Switzerland, mainly to the Canton of Zurich, for the sole purpose of committing suicide. Political debate regarding ‘suicide tourism’ is taking place in many countries. Swiss medicolegal experts are confronted with these cases almost daily, which prompted our scientific investigation of the phenomenon. The present study has three aims: (1) to determine selected details about AS in the study group (age, gender and country of residence of the suicide tourists, the organisation involved, the ingested substance leading to death and any diseases that were the main reason for AS); (2) to find out the countries from which suicide tourists come and to review existing laws in the top three in order to test the hypothesis that suicide tourism leads to the amendment of existing regulations in foreign countries; and (3) to compare our results with those of earlier studies in Zurich. We did a retrospective data analysis of the Zurich Institute of Legal Medicine database on AS of on-Swiss residents in the last 5 years (2008–2012), and internet research for current legislation and political debate in the three foreign countries most concerned. We analysed 611 cases from 31 countries all over the world. Non-terminal conditions such as neurological and rheumatic diseases are increasing among suicide tourists. The unique phenomenon of suicide tourism in Switzerland may indeed result in the amendment or supplementary guidelines to existing regulations in foreign countries.

Fluid-structure interaction of an elastic pipe immersed inside a coaxial rigid pipe: a model for the Tullio phenomenon

An axisymmetric, elastic pipe is filled with an incompressible fluid and is immersed in a second, coaxial rigid pipe which contains the same fluid. A pressure pulse in the outer fluid annulus deforms the elastic pipe which invokes a fluid motion in the fluid core. It is the aim of this study to investigate streaming phenomena in the core which may originate from such a fluid-structure interaction. This work presents a numerical solver for such a configuration. It was developed in the OpenFOAM software environment and is based on the Arbitrary Lagrangian Eulerian (ALE) approach for moving meshes. The solver features a monolithic integration of the one-dimensional, coupled system between the elastic structure and the outer fluid annulus into a dynamic boundary condition for the moving surface of the fluid core. Results indicate that our configuration may serve as a mechanical model of the Tullio Phenomenon (sound-induced vertigo).

Does the use of multiple FTAs force firms to raise local input share? : evidence of the spaghetti bowl phenomenon

This paper empirically investigates the firm-level relationship between the local input share and the number of used FTAs by employing the data on FTA utilization in Japanese affiliates in ASEAN. As a result, we do not find a robust linear relationship. However, affiliates using a large number of FTAs (seven or eight) have an extremely higher share of local inputs. This result might be interpreted as the first evidence of the “spaghetti bowl phenomenon”.

Simulation of Freight Trains Equipped with Partially Filled Tank Containers and Related Resonance Phenomenon

To study the fluid motion-vehicle dynamics interaction, a model of four, liquid filled two-axle container freight wagons was set up. The railway vehicle has been modelled as a multi-body system (MBS). To include fluid sloshing, an equivalent mechanical model has been developed and incorporated. The influence of several factors has been studied in computer simulations, such as track defects, curve negotiation, train velocity, wheel wear, liquid and solid wagonload, and container baffles. SIMPACK has been used for MBS analysis, and ANSYS for liquid sloshing modelling and equivalent mechanical systems validation. Acceleration and braking manoeuvres of the freight train set the liquid cargo into motion. This longitudinal sloshing motion of the fluid cargo inside the tanks initiated a swinging motion of some components of the coupling gear. The coupling gear consists of UIC standard traction hooks and coupling screws that are located between buffers. One of the coupling screws is placed in the traction hook of the opposite wagon thus joining the two wagons, whereas the unused coupling screw rests on a hanger. Simulation results showed that, for certain combinations of type of liquid, filling level and container dimensions, the liquid cargo could provoke an undesirable, although not hazardous, release of the unused coupling screw from its hanger. The coupling screw's release was especially obtained when a period of acceleration was followed by an abrupt braking manoeuvre at 1 m/s2. It was shown that a resonance effect between the liquid's oscillation and the coupling screw's rotary motion could be the reason for the coupling screw's undesired release. Possible solutions to avoid the phenomenon are given.Acceleration and braking manoeuvres of the freight train set the liquid cargo into motion. This longitudinal sloshing motion of the fluid cargo inside the tanks initiated a swinging motion of some components of the coupling gear. The coupling gear consists of UIC standard traction hooks and coupling screws that are located between buffers. One of the coupling screws is placed in the traction hook of the opposite wagon thus joining the two wagons, whereas the unused coupling screw rests on a hanger. This paper reports on a study of the fluid motion-train vehicle dynamics interaction. In the study, a model of four, liquid-filled two-axle container freight wagons was developed. The railway vehicle has been modeled as a multi-body system (MBS). To include fluid sloshing, an equivalent mechanical model has been developed and incorporated. The influence of several factors has been studied in computer simulations, such as track defects, curve negotiation, train velocity, wheel wear, liquid and solid wagonload, and container baffles. A simulation program was used for MBS analysis, and a finite element analysis program was used for liquid sloshing modeling and equivalent mechanical systems validation. Acceleration and braking maneuvers of the freight train set the liquid cargo into motion. This longitudinal sloshing motion of the fluid cargo inside the tanks initiated a swinging motion of some components of the coupling gear. Simulation results showed that, for certain combinations of type of liquid, filling level and container dimensions, the liquid cargo could provoke an undesirable, although not hazardous, release of an unused coupling screw from its hanger. It was shown that a resonance effect between the liquid's oscillation and the coupling screw's rotary motion could be the reason for the coupling screw's undesired release. Solutions are suggested to avoid the resonance problem, and directions for future research are given.