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1.
Proc Natl Acad Sci U S A ; 121(6): e2313962121, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38306480

ABSTRACT

Ultralight architected materials enabled by advanced manufacturing processes have achieved density-normalized strength and stiffness properties that are inaccessible to bulk materials. However, the majority of this work has focused on static loading and elastic-wave propagation. Fundamental understanding of the mechanical behavior of architected materials under large-deformation dynamic conditions remains limited, due to the complexity of mechanical responses and shortcomings of characterization methods. Here, we present a microscale suspended-plate impact testing framework for three-dimensional micro-architected materials, where supersonic microparticles to velocities of up to 850 m/s are accelerated against a substrate-decoupled architected material to quantify its energy dissipation characteristics. Using ultra-high-speed imaging, we perform in situ quantification of the impact energetics on two types of architected materials as well as their constituent nonarchitected monolithic polymer, indicating a 47% or greater increase in mass-normalized energy dissipation under a given impact condition through use of architecture. Post-mortem characterization, supported by a series of quasi-static experiments and high-fidelity simulations, shed light on two coupled mechanisms of energy dissipation: material compaction and particle-induced fracture. Together, experiments and simulations indicate that architecture-specific resistance to compaction and fracture can explain a difference in dynamic impact response across architectures. We complement our experimental and numerical efforts with dimensional analysis which provides a predictive framework for kinetic-energy absorption as a function of material parameters and impact conditions. We envision that enhanced understanding of energy dissipation mechanisms in architected materials will serve to define design considerations toward the creation of lightweight impact-mitigating materials for protective applications.

2.
Nature ; 623(7987): 514-521, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37968526

ABSTRACT

Mechanical metamaterials at the microscale exhibit exotic static properties owing to their engineered building blocks1-4, but their dynamic properties have remained substantially less explored. Their design principles can target frequency-dependent properties5-7 and resilience under high-strain-rate deformation8,9, making them versatile materials for applications in lightweight impact resistance10-12, acoustic waveguiding7,13 or vibration damping14,15. However, accessing dynamic properties at small scales has remained a challenge owing to low-throughput and destructive characterization8,16,17 or lack of existing testing protocols. Here we demonstrate a high-throughput, non-contact framework that uses MHz-wave-propagation signatures within a metamaterial to non-destructively extract dynamic linear properties, omnidirectional elastic information, damping properties and defect quantification. Using rod-like tessellations of microscopic metamaterials, we report up to 94% direction-dependent and rate-dependent dynamic stiffening at strain rates approaching 102 s-1, as well as damping properties three times higher than their constituent materials. We also show that frequency shifts in the vibrational response allow for characterization of invisible defects within the metamaterials and that selective probing allows for the construction of experimental elastic surfaces, which were previously only possible computationally. Our work provides a route for accelerated data-driven discovery of materials and microdevices for dynamic applications such as protective structures, medical ultrasound or vibration isolation.

3.
Nano Lett ; 23(11): 5155-5163, 2023 Jun 14.
Article in English | MEDLINE | ID: mdl-37216440

ABSTRACT

Self-assembled nanoparticle superlattices (NPSLs) are an emergent class of self-architected nanocomposite materials that possess promising properties arising from precise nanoparticle ordering. Their multiple coupled properties make them desirable as functional components in devices where mechanical robustness is critical. However, questions remain about NPSL mechanical properties and how shaping them affects their mechanical response. Here, we perform in situ nanomechanical experiments that evidence up to an 11-fold increase in stiffness (∼1.49 to 16.9 GPa) and a 5-fold increase in strength (∼88 to 426 MPa) because of surface stiffening/strengthening from shaping these nanomaterials via focused-ion-beam milling. To predict the mechanical properties of shaped NPSLs, we present discrete element method (DEM) simulations and an analytical core-shell model that capture the FIB-induced stiffening response. This work presents a route for tunable mechanical responses of self-architected NPSLs and provides two frameworks to predict their mechanical response and guide the design of future NPSL-containing devices.

4.
J. health inform ; 14(1): 11-18, jan.-mar. 2022. ilus, tab
Article in Portuguese | LILACS | ID: biblio-1370252

ABSTRACT

Objetivo: Este artigo apresenta uma proposta de processo de avaliação da usabilidade de aplicativos móveis para prática de exercícios físicos. Método: Inicialmente, realizou-se um mapeamento sistemático da literatura a fim de identificar quais métodos de avaliação de usabilidade são mais adequados para avaliar a interface de aplicativos de exercícios físicos. Em seguida, definiu-se um processo de avaliação baseado nas principais etapas dos métodos identificados. Posteriormente, esse processo foi utilizado na avaliação do aplicativo Exercícios em Casa. Resultados: Os resultados do mapeamento sistemático apontam como métodos mais utilizados o questionário System Usability Scale (SUS) (42%), o método think aloud (14%) e a técnica cognitive walkthrough (7%). O processo proposto foi modelado usando a notação SPEM para descrever a sequência de etapas necessárias para integrar estes três métodos. Após a modelagem, a proposta foi aplicada por três avaliadores que elencaram uma série de recomendações para melhoria do processo. Conclusão: Espera-se que esse processo permita aos desenvolvedores e projetistas de aplicativos móveis elaborarem aplicativos mais aderentes às necessidades de usuários/praticantes de exercícios físicos.


Objective: This paper presents a proposal of usability evaluation process of mobile fitness applications. Method: Firstly, a systematic literature mapping was carried out in order to identify most suitable usability evaluation methods for evaluating the interface of physical exercise applications. Then, an usability evaluation process was defined based on the main steps of the identified methods. Subsequently, this process was used in the evaluation of the mobile application "Exercícios em Casa" (Exercises at Home application). Results: The results of the systematic mapping indicate as the most used methods the System Usability Scale (SUS) questionnaire (42%), the think aloud method (14%) and the cognitive walkthrough technique (7%). The proposed process was modeled using SPEM notation to describe the sequence of steps required to integrate these three methods. After the modeling, the proposal was applied by three evaluators who listed a series of recommendations for the process improvement. Conclusion: We expect that this process allows developers and designers of mobile applications to develop tools more adherent to the needs of users/practitioners of physical exercise.


Objetivo: Este artículo presenta una propuesta de proceso de evaluación de usabilidad de aplicaciones de fitness móvil. Método: En primer lugar, se realizó un mapeo sistemático de la literatura con el fin de identificar los métodos de evaluación de la usabilidad más adecuados para evaluar la interfaz de las aplicaciones de ejercicios físicos. El proceso de evaluación se definió con base en los pasos principales de los métodos identificados. Posteriormente, este proceso fue utilizado en la evaluación de la aplicación móvil "Exercícios em Casa" (Ejercicios en Casa). Resultados: Los resultados del mapeo sistemático señalan como los métodos más utilizados el cuestionario System Usability Scale (SUS) (42%), el think aloud (14%) y la técnica de cognitive walkthrough (7%). El proceso propuesto se modeló utilizando la notación SPEM para describir la secuencia de pasos necesarios para integrar estos tres métodos. Luego del modelado, la propuesta fue aplicada por tres evaluadores quienes enlistaron una serie de recomendaciones para la mejora del proceso. Conclusión: Esperamos que este proceso permita a los programadores y diseñadores de aplicaciones móviles programar aplicaciones más acordes a las necesidades de los usuarios/practicantes de ejercicios físicos.


Subject(s)
Humans , Exercise , Mobile Applications , User-Centered Design , Surveys and Questionnaires , Physical Distancing , COVID-19/prevention & control
5.
Nat Commun ; 13(1): 1041, 2022 Feb 24.
Article in English | MEDLINE | ID: mdl-35210416

ABSTRACT

Mechanical metamaterials have been designed to achieve custom Poisson's ratios via the deformation of their microarchitecture. These designs, however, have yet to achieve the capability of exhibiting Poisson's ratios that alternate by design both temporally and spatially according to deformation. This capability would enable dynamic shape-morphing applications including smart materials that process mechanical information according to multiple time-ordered output signals without requiring active control or power. Herein, both periodic and graded metamaterials are introduced that leverage principles of differential stiffness and self-contact to passively achieve sequential deformations, which manifest as user-specified alternating Poisson's ratios. An analytical approach is provided with a complementary software tool that enables the design of such materials in two- and three-dimensions. This advance in design capability is due to the fact that the tool computes sequential deformations more than an order of magnitude faster than contemporary finite-element packages. Experiments on macro- and micro-scale designs validate their predicted alternating Poisson's ratios.

6.
Rev Esp Enferm Dig ; 114(2): 103-106, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34154368

ABSTRACT

OBJECTIVE: to validate the incidence of inflammatory bowel disease (IBD) reported in Vigo in 2010 within the Epi-IBD study, which was the highest incidence reported so far in Spain. METHODS: an epidemiological, prospective, population-based inception cohort study. All incident cases of IBD living in the Vigo area at diagnosis from January 1 to December 31, 2011 were included. RESULTS: one hundred patients were diagnosed (62 % men; median age, 43.27 years): 49 with ulcerative colitis (UC), 34 with Crohn's disease (CD), and 17 with IBD unclassified (IBDU). The incidence (per 100,000 inhabitants/year) was 17.56 (CD: 5.97; UC: 8.60; IBDU: 2.98), similar to that reported in 2010. The incidence in the non-pediatric population was 19.66 (CD: 6.89, UC: 9.52; IBDU: 3.04). CD and UC phenotype was similar in 2010 and 2011. CONCLUSION: this study supports the increased incidence of EII in the Vigo area reported in 2010.


Subject(s)
Colitis, Ulcerative , Crohn Disease , Inflammatory Bowel Diseases , Cohort Studies , Colitis, Ulcerative/diagnosis , Colitis, Ulcerative/epidemiology , Crohn Disease/diagnosis , Crohn Disease/epidemiology , Humans , Incidence , Inflammatory Bowel Diseases/diagnosis , Inflammatory Bowel Diseases/epidemiology , Phenotype , Prospective Studies
7.
Nat Mater ; 20(11): 1491-1497, 2021 11.
Article in English | MEDLINE | ID: mdl-34168332

ABSTRACT

Architected materials with nanoscale features have enabled extreme combinations of properties by exploiting the ultralightweight structural design space together with size-induced mechanical enhancement at small scales. Apart from linear waves in metamaterials, this principle has been restricted to quasi-static properties or to low-speed phenomena, leaving nanoarchitected materials under extreme dynamic conditions largely unexplored. Here, using supersonic microparticle impact experiments, we demonstrate extreme impact energy dissipation in three-dimensional nanoarchitected carbon materials that exhibit mass-normalized energy dissipation superior to that of traditional impact-resistant materials such as steel, aluminium, polymethyl methacrylate and Kevlar. In-situ ultrahigh-speed imaging and post-mortem confocal microscopy reveal consistent mechanisms such as compaction cratering and microparticle capture that enable this superior response. By analogy to planetary impact, we introduce predictive tools for crater formation in these materials using dimensional analysis. These results substantially uncover the dynamic regime over which nanoarchitecture enables the design of ultralightweight, impact-resistant materials that could open the way to design principles for lightweight armour, protective coatings and blast-resistant shields for sensitive electronics.


Subject(s)
Carbon , Polymethyl Methacrylate , Polymethyl Methacrylate/chemistry
8.
Adv Sci (Weinh) ; 7(20): 2001271, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33101856

ABSTRACT

Hierarchy in natural and synthetic materials has been shown to grant these architected materials properties unattainable independently by their constituent materials. While exceptional mechanical properties such as extreme resilience and high deformability have been realized in many human-made three-dimensional (3D) architected materials using beam-and-junction-based architectures, stress concentrations and constraints induced by the junctions limit their mechanical performance. A new hierarchical architecture in which fibers are interwoven to construct effective beams is presented. In situ tension and compression experiments of additively manufactured woven and monolithic lattices with 30 µm unit cells demonstrate the superior ability of woven architectures to achieve high tensile and compressive strains (>50%)-without failure events-via smooth reconfiguration of woven microfibers in the effective beams and junctions. Cyclic compression experiments reveal that woven lattices accrue less damage compared to lattices with monolithic beams. Numerical studies of woven beams with varying geometric parameters present new design spaces to develop architected materials with tailored compliance that is unachievable by similarly configured monolithic-beam architectures. Woven hierarchical design offers a pathway to make traditionally stiff and brittle materials more deformable and introduces a new building block for 3D architected materials with complex nonlinear mechanics.

9.
Proc Natl Acad Sci U S A ; 117(11): 5686-5693, 2020 03 17.
Article in English | MEDLINE | ID: mdl-32132212

ABSTRACT

Low-density materials with tailorable properties have attracted attention for decades, yet stiff materials that can resiliently tolerate extreme forces and deformation while being manufactured at large scales have remained a rare find. Designs inspired by nature, such as hierarchical composites and atomic lattice-mimicking architectures, have achieved optimal combinations of mechanical properties but suffer from limited mechanical tunability, limited long-term stability, and low-throughput volumes that stem from limitations in additive manufacturing techniques. Based on natural self-assembly of polymeric emulsions via spinodal decomposition, here we demonstrate a concept for the scalable fabrication of nonperiodic, shell-based ceramic materials with ultralow densities, possessing features on the order of tens of nanometers and sample volumes on the order of cubic centimeters. Guided by simulations of separation processes, we numerically show that the curvature of self-assembled shells can produce close to optimal stiffness scaling with density, and we experimentally demonstrate that a carefully chosen combination of topology, geometry, and base material results in superior mechanical resilience in the architected product. Our approach provides a pathway to harnessing self-assembly methods in the design and scalable fabrication of beyond-periodic and nonbeam-based nano-architected materials with simultaneous directional tunability, high stiffness, and unsurpassed recoverability with marginal deterioration.

10.
Nature ; 573(7773): 205-213, 2019 09.
Article in English | MEDLINE | ID: mdl-31511685

ABSTRACT

Architected materials can actively respond to external stimuli-such as mechanical forces, hydration and magnetic fields-by changing their geometries and thereby achieve novel functionalities. Such transformations are usually binary and volatile because they toggle between 'on' and 'off' states and require persistent external stimuli. Here we develop three-dimensional silicon-coated tetragonal microlattices that transform into sinusoidal patterns via cooperative beam buckling in response to an electrochemically driven silicon-lithium alloying reaction. In situ microscopy reveals a controllable, non-volatile and reversible structural transformation that forms multiple ordered buckling domains separated by distorted domain boundaries. We investigate the mechanical dynamics of individual buckling beams, cooperative coupling among neighbouring beams, and lithiation-rate-dependent distributions of domain sizes through chemo-mechanical modelling and statistical mechanics analysis. Our results highlight the critical role of defects and energy fluctuations in the dynamic response of architected materials. We further demonstrate that domain boundaries can be programmed to form particular patterns by pre-designing artificial defects, and that a variety of reconfigurational degrees of freedom can be achieved through micro-architecture design. This framework enables the design, fabrication, modelling, behaviour prediction and programming of electrochemically reconfigurable architected materials, and could open the way to beyond-intercalation battery electrodes, tunable phononic crystals and bio-implantable devices.

11.
Rev. cuba. cir ; 58(2): e645, mar.-jun. 2019. graf
Article in Spanish | LILACS | ID: biblio-1093165

ABSTRACT

RESUMEN La amputación traumática completa se define como la separación total de un segmento del miembro del resto del cuerpo. El segmento cercenado algunas veces se puede reconectar, siempre que ambas partes de la extremidad hayan sido correctamente tratadas y se cumplan determinadas condiciones. Se presentan dos casos de amputación traumática de ambos miembros inferiores: el primero, una paciente femenina de 49 años de edad, debido a un accidente de trabajo y, el segundo, un paciente masculino de 39 años, víctima de un accidente en las vías férreas. Se expone la sintomatología presentada por ambos pacientes, su tratamiento quirúrgico y evolución(AU)


ABSTRACT Complete traumatic amputation is defined as the total separation of a limb segment from the rest of the body. The severed segment can sometimes be reconnected, provided that both parts of the limb have been correctly treated and certain conditions are met. Two cases of traumatic amputation of both lower limbs are presented: the first, a female patient of 49 years of age, due to an accident at work; and the second, a male patient of 39 years, victim of a railroad accident. The symptoms presented by both patients, their surgical treatment and evolution are exposed(AU)


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Accidents, Occupational , Lower Extremity/injuries , Amputation, Traumatic/surgery
12.
Rev. cuba. cir ; 58(2): e648, mar.-jun. 2019. graf
Article in Spanish | LILACS | ID: biblio-1093166

ABSTRACT

RESUMEN Se presenta el caso de un paciente masculino de 39 años de edad, que acude al cuerpo de guardia del Hospital General Docente Abel Santamaría Cuadrado por presentar un cuadro de dolor abdominal de tres días de evolución. Se interviene quirúrgicamente con el diagnóstico presuntivo de apendicitis aguda complicada. En el acto quirúrgico se comprobó que el apéndice cecal era normal y al examinar el íleon terminal, a una distancia aproximada de 50 cm se encontró un divertículo de Meckel, y a 5 cm de este, una espina de pescado adherida a la pared intestinal, la cual parecía ser la causante del cuadro, ya que el divertículo también era normal. El tratamiento consistió en trasladar la espina hacia el divertículo y realizar resección intestinal de ese tramo con anastomosis término-terminal. La evolución posoperatoria fue satisfactoria y el paciente fue dado de alta a los 8 días de la operación(AU)


ABSTRACT We present the case of a male patient, 39 years of age, who presents to the emergency room of Abel Santamaría Cuadrado General Teaching Hospital with a clinical picture of abdominal pain of three days of natural history. He is surgically intervened with the presumptive diagnosis of complicated acute appendicitis. In the surgical act, the cecal appendix was verified to be normal and, when examining the terminal ileum, at a distance of approximately 50 cm, a Meckel's diverticulum was found, and, at 5 cm from this, a fish spine adhered to the intestinal wall, which seemed to be the cause of the clinical picture, since the diverticulum was also normal. The treatment consisted of transferring the spine to the diverticulum and performing intestinal resection of that section with end-to-end anastomosis. The postoperative evolution was satisfactory and the patient was discharged 8 days after the operation(AU)


Subject(s)
Humans , Male , Adult , Appendicitis/diagnosis , Abdominal Pain/etiology , Foreign Bodies/surgery , Intestine, Small/diagnostic imaging , Meckel Diverticulum/surgery
13.
Nat Commun ; 10(1): 291, 2019 01 17.
Article in English | MEDLINE | ID: mdl-30655524

ABSTRACT

Designing mechanical metamaterials is overwhelming for most computational approaches because of the staggering number and complexity of flexible elements that constitute their architecture-particularly if these elements don't repeat in periodic patterns or collectively occupy irregular bulk shapes. We introduce an approach, inspired by the freedom and constraint topologies (FACT) methodology, that leverages simplified assumptions to enable the design of such materials with ~6 orders of magnitude greater computational efficiency than other approaches (e.g., topology optimization). Metamaterials designed using this approach are called directionally compliant metamaterials (DCMs) because they manifest prescribed compliant directions while possessing high stiffness in all other directions. Since their compliant directions are governed by both macroscale shape and microscale architecture, DCMs can be engineered with the necessary design freedom to facilitate arbitrary form and unprecedented anisotropy. Thus, DCMs show promise as irregularly shaped flexure bearings, compliant prosthetics, morphing structures, and soft robots.

14.
Nano Lett ; 18(8): 4755-4761, 2018 08 08.
Article in English | MEDLINE | ID: mdl-30022671

ABSTRACT

Creating materials that simultaneously possess ultralow thermal conductivity, high stiffness, and damage tolerance is challenging because thermal and mechanical properties are coupled in most fully dense and porous solids. Nanolattices can fill this void in the property space because of their hierarchical design and nanoscale features. We report that nanolattices composed of 24- to 182-nm-thick hollow alumina beams in the octet-truss architecture achieved thermal conductivities as low as 2 mW m-1 K-1 at room temperature while maintaining specific stiffnesses of 0.3 to 3 MPa kg-1 m3 and the ability to recover from large deformations. These nanoarchitected materials possess the same ultralow thermal conductivities as aerogels while attaining specific elastic moduli that are nearly 2 orders of magnitude higher. Our work demonstrates a general route to realizing multifunctional materials that occupy previously unreachable regions within the material property space.

15.
Nat Commun ; 9(1): 593, 2018 02 09.
Article in English | MEDLINE | ID: mdl-29426947

ABSTRACT

Most existing methods for additive manufacturing (AM) of metals are inherently limited to ~20-50 µm resolution, which makes them untenable for generating complex 3D-printed metallic structures with smaller features. We developed a lithography-based process to create complex 3D nano-architected metals with ~100 nm resolution. We first synthesize hybrid organic-inorganic materials that contain Ni clusters to produce a metal-rich photoresist, then use two-photon lithography to sculpt 3D polymer scaffolds, and pyrolyze them to volatilize the organics, which produces a >90 wt% Ni-containing architecture. We demonstrate nanolattices with octet geometries, 2 µm unit cells and 300-400-nm diameter beams made of 20-nm grained nanocrystalline, nanoporous Ni. Nanomechanical experiments reveal their specific strength to be 2.1-7.2 MPa g-1 cm3, which is comparable to lattice architectures fabricated using existing metal AM processes. This work demonstrates an efficient pathway to 3D-print micro-architected and nano-architected metals with sub-micron resolution.

16.
Rev. cuba. cir ; 55(4): 348-354, oct.-dic. 2016. ilus
Article in Spanish | LILACS | ID: biblio-844834

ABSTRACT

La incidencia de TB intestinal es desconocida, ya que puede ser asintomática y por su naturaleza a menudo resulta en diagnósticos erróneos, por lo que se debe tener un alto índice de sospecha en poblaciones de alto riesgo. Los abscesos intrabdominales en el curso de esta es una complicación poco frecuente, con una incidencia entre 2 y 30 por ciento. Presentamos un paciente masculino de 52 años de edad, con masa abdominal en mesogástrio, asociada a dolor abdominal y pérdida de peso. Se comienza su estudio con Rx. de tórax y ecografía abdominal, el cual reporta masa de 90 x 47 mm en el peritoneo, es intervenido quirúrgicamente y drenado por absceso intrabdominal. Se diagnostica TB intestinal, su evolución fue satisfactoria después de iniciado el tratamiento antituberculoso. Ante un paciente con síntomas de abdomen agudo, es importante realizar un diagnóstico temprano de TB intestinal. Esto evitaría una intervención innecesaria, porque el diagnóstico de la TB intestinal es médico. Si se realiza la intervención, puede confirmarse el diagnóstico mediante las lesiones encontradas; acción que impediría una resección intestinal innecesaria pues el tratamiento antituberculoso resolvería la TB. Generalmente, el diagnóstico se realiza durante una cirugía o por procedimientos invasivos con otros propósitos, por ser esta de difícil diagnóstico clínico y que la irregularidad del tratamiento antituberculoso es un importante factor de riesgo para el desarrollo de complicaciones en la TB intestinal diagnosticada. Esta es altamente efectivo en la resolución de complicaciones de moderada gravedad como la obstrucción intestinal y los abscesos intrabdominales(AU)


The incidence of intestinal tuberculosis is unknown since it may be symptom-free and lead to frequent misdiagnoses, so one should highly suspect of intestinal tuberculosis in high risk populations. The intra-abdominal abscesses are rare complications, with an incidence rate of 2 to 30 percent. Here is the case of a 52 years-old male patient who had an abdominal in her mesogastrium associated to abdominal pain and weight loss. The first testing was thorax X-ray and abdominal ultrasound, which revealed the presence of a 90x74mm mass in the peritoneum. As a result, he was operated on including intrabdominal abscess drainage. The final diagnosis was intestinal tuberculosis, being the recovery satisfactory after the anti-tuberculosis treatment. It is fundamental to make emphasis on the importance of early diagnosis of intestinal tuberculosis in patients with acute abdomen symptoms in risk groups since this may avoid surgical treatment. The diagnosis based on macroscopic findings in case of surgical treatment may also avoid unnecessary intestinal resections. Generally speaking, the diagnosis is made during a surgery or by invasive procedures with other purposes since the clinical diagnosis is difficult; irregular anti-tuberculosis treatment is a significant risk factor for the development of complications in diagnosed intestinal tuberculosis. It is highly effective in the resolution of moderate-severity complications such as intestinal obstruction and intra-abdominal abscesse(AU)


Subject(s)
Humans , Male , Middle Aged , Abdominal Abscess/diagnosis , Radiography, Abdominal/adverse effects , Tuberculosis, Gastrointestinal/complications , Tuberculosis, Gastrointestinal/therapy , Clinical Diagnosis
17.
Rev. cuba. cir ; 55(4): 348-354, oct.-dic. 2016. ilus
Article in Spanish | CUMED | ID: cum-67135

ABSTRACT

La incidencia de TB intestinal es desconocida, ya que puede ser asintomática y por su naturaleza a menudo resulta en diagnósticos erróneos, por lo que se debe tener un alto índice de sospecha en poblaciones de alto riesgo. Los abscesos intrabdominales en el curso de esta es una complicación poco frecuente, con una incidencia entre 2 y 30 por ciento. Presentamos un paciente masculino de 52 años de edad, con masa abdominal en mesogástrio, asociada a dolor abdominal y pérdida de peso. Se comienza su estudio con Rx. de tórax y ecografía abdominal, el cual reporta masa de 90 x 47 mm en el peritoneo, es intervenido quirúrgicamente y drenado por absceso intrabdominal. Se diagnostica TB intestinal, su evolución fue satisfactoria después de iniciado el tratamiento antituberculoso. Ante un paciente con síntomas de abdomen agudo, es importante realizar un diagnóstico temprano de TB intestinal. Esto evitaría una intervención innecesaria, porque el diagnóstico de la TB intestinal es médico. Si se realiza la intervención, puede confirmarse el diagnóstico mediante las lesiones encontradas; acción que impediría una resección intestinal innecesaria pues el tratamiento antituberculoso resolvería la TB. Generalmente, el diagnóstico se realiza durante una cirugía o por procedimientos invasivos con otros propósitos, por ser esta de difícil diagnóstico clínico y que la irregularidad del tratamiento antituberculoso es un importante factor de riesgo para el desarrollo de complicaciones en la TB intestinal diagnosticada. Esta es altamente efectivo en la resolución de complicaciones de moderada gravedad como la obstrucción intestinal y los abscesos intrabdominales(AU)


The incidence of intestinal tuberculosis is unknown since it may be symptom-free and lead to frequent misdiagnoses, so one should highly suspect of intestinal tuberculosis in high risk populations. The intra-abdominal abscesses are rare complications, with an incidence rate of 2 to 30%. Here is the case of a 52 years-old male patient who had an abdominal in her mesogastrium associated to abdominal pain and weight loss. The first testing was thorax X-ray and abdominal ultrasound, which revealed the presence of a 90x74mm mass in the peritoneum. As a result, he was operated on including intrabdominal abscess drainage. The final diagnosis was intestinal tuberculosis, being the recovery satisfactory after the anti-tuberculosis treatment. It is fundamental to make emphasis on the importance of early diagnosis of intestinal tuberculosis in patients with acute abdomen symptoms in risk groups since this may avoid surgical treatment. The diagnosis based on macroscopic findings in case of surgical treatment may also avoid unnecessary intestinal resections. Generally speaking, the diagnosis is made during a surgery or by invasive procedures with other purposes since the clinical diagnosis is difficult; irregular anti-tuberculosis treatment is a significant risk factor for the development of complications in diagnosed intestinal tuberculosis. It is highly effective in the resolution of moderate-severity complications such as intestinal obstruction and intra-abdominal abscesses.


Subject(s)
Humans , Male , Middle Aged , Tuberculosis, Gastrointestinal/complications , Tuberculosis, Gastrointestinal/therapy , Radiography, Abdominal/adverse effects , Abdominal Abscess/diagnosis , Clinical Diagnosis , Risk Factors
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