miércoles, 31 de agosto de 2011

APRENDIZAJE BASADO EN UN CASO

A 55-year-old man presents to the emergency department (ED) with a 2-day history of nausea and vomiting. He has been seen a few times in the gastroenterology clinic during the past 6 months for similar symptoms. Multivitamins, antacids, and proton-pump inhibitors had been prescribed but failed to control his symptoms. He has no history of trauma, weight loss, fever, dyspnea, abdominal pain, hematemesis, diarrhea, constipation, or peripheral edema. Six years ago, he was diagnosed with type 2 diabetes and was prescribed an oral agent and a long-acting insulin. Although he was nonadherent to his recommended diet, he used his medications as prescribed. Four years ago, the patient began experiencing hypoglycemic episodes even though his daily activity and diet had not changed and his weight had remained stable. From that point on, he gradually tapered his insulin use and eventually stopped both insulin and his oral medication. Following that, occasional fingerstick glucose measurements were reportedly normal. He does not smoke tobacco, drink alcohol, or use illicit drugs.

On physical examination, the patient's axillary temperature is 97.7ºF (36.5ºC). His pulse has a regular rhythm, with a heart rate of 62 bpm. His blood pressure is 100/70 mm Hg. He appears apathetic and unwell. Head and neck examination reveals fine wrinkling of the perioral skin. His lungs are clear. His S1 and S2 heart sounds are normal. His abdomen is soft and nontender, and his peripheral pulses are weakly palpable.


Laboratory analysis reveals normochromic normocytic anemia, with a hemoglobin level of 11.8 g/dL (118 g/L; normal range, 13.5-18 g/dL), a hematocrit of 34% (0.34; normal range, 40%-54%) and a mean corpuscular volume of 91 μm3 (91 fL; normal range, 80-96 μm3). The remainder of the CBC count is normal, as is urinalysis and a random blood glucose level. The patient's renal function and liver function tests are normal. He has hyponatremia, with a serum sodium of 126 mEq/L (126 mmol/L; normal range of 136-145 mEq/L). His serum potassium level is normal. When further queried about his medical history and review of systems, he reports having a decreased libido and impotence for 3 years. The patient is hospitalized for further evaluation of his hyponatremia and progressive symptoms. Cranial magnetic resonance imaging (MRI) is obtained.



El aceite de oliva y los frutos secos revierten la arteriosclerosis


Un estudio de la Universidad de Navarra muestra que la modificación del patrón dietético logra reducir en apenas un año el espesor de la capa íntima-media de la arteria carótida
Una dieta mediterránea enriquecida con aceite de oliva virgen o con frutos secos puede revertir la arteriosclerosis en las arterias carotídeas en sólo un año, según se ha demostrado en un ensayo realizado con 187 voluntarios en la Universidad de Navarra, que ahora publica la revista Atherosclerosis.
Los participantes, mayores de 55 años y con alto riesgo cardiovascular, se dividieron en tres grupos al azar. Dos de ellos recibieron instrucciones detalladas sobre cómo seguir de forma adecuada una dieta mediterránea mediante entrevistas trimestrales con dietistas nutricionistas formadas para esta tarea y dirigidas por Ana Sánchez-Tainta, especialista en Nutrición Humana y Dietética en el centro académico.
Uno de los grupos recibió 15 litros de aceite de oliva virgen cada trimestre; al otro se le facilitaron frutos secos para que los voluntarios consumieran 30 gramos diarios de nueves, almendras y avellanas. Por último, al tercer grupo se le dieron instrucciones para seguir una dieta baja en grasa.
A todos ellos se les midió el espesor de la capa íntima-media de la arteria carótida por ecografía, tanto al principio del estudio como al cabo de un año. "Fue así”, afirma Sánchez-Tainta, “como que las personas que habían seguido una dieta mediterránea enriquecida con aceite de oliva virgen o con frutos secos presentaban una regresión del grosor de dicha capa”
Respecto a los resultados obtenidos, el director del proyecto y catedrático de Medicina Preventiva de la Universidad de Navarra, Miguel Ángel Martínez, subraya que "una modificación de todo el patrón dietético es capaz de conseguir en un solo año unos resultados que no se alcanzan con los fármacos que se prescriben ni siquiera en dos años de tratamiento".


Tomado de Jano.es


lunes, 22 de agosto de 2011

APRENDIZAJE BASADO EN UN CASO

75-year-old man presents to the emergency department (ED) with a 6-week history of worsening lower abdominal pain. He describes the pain as sharp, constant, and associated with a weight loss of approximately 20 lb over the past month. The patient states that for the past few weeks he has also noticed bilateral lower-extremity swelling and abdominal distention. The abdominal distention has been severe enough to prevent him from bending over. He experienced an increased frequency of urination until 3 days ago; he has been anuric since then. For the past week he has not been able to tolerate solid foods, resulting in an entirely liquid diet. As of the day of presentation even liquids have become intolerable. There is also a history of numbness and tingling in both legs and an unsteady gait during the last week. He reports a feeling of confusion but is fully oriented to person, place, and time. His medical history is significant for hypertension under treatment and mitral valve insufficiency. He denies any surgical history. His current medications include daily aspirin and nifedipine. The patient has an age-appropriate level of physical activity and lives alone. He does not smoke or drink.


On physical examination, the patient is a well-oriented elderly man in no acute distress. His vital signs include an oral temperature of 97.4°F (36.3°C), a blood pressure of 211/92 mm Hg, a pulse of 104 beats/min, an unlabored respiratory rate of 20 breaths/min, and an oxygen saturation of 97% on room air. Head and neck examination reveals dry oral mucous membranes with a supple neck and no jugular venous distention. The chest examination is clear to auscultation bilaterally, with normal breath sounds and normal S1 and S2 heart sounds without murmurs, rubs, or gallops. The abdominal examination is significant for distention, mostly in the hypogastric and umbilical regions, and for the presence of a reducible umbilical hernia. Normal bowel sounds are appreciated in all quadrants. The patient's lower abdomen is diffusely tender, with slight tenderness noted in the upper abdomen as well. There is no rebound tenderness or guarding and Lloyd's sign is negative. Extremity examination is significant for bilateral pitting edema of the lower extremities. The patient has no focal neurologic abnormalities (although gait testing is deferred).


Initial laboratory investigations include a complete blood count (CBC) and basic metabolic panel. There are no significant findings on the CBC. The metabolic panel reveals a serum sodium level of 130 mEq/L (normal range, 136-145 mEq/L), potassium of 4.2 mEq/L (normal range, 3.5-5.0 mEq/L), chloride of 83 mEq/L (normal range, 95-105 mEq/L), bicarbonate of 16 mEq/L (normal range, 22-28 mEq/L), and glucose of 92 mg/dL (normal range, 70-125 mg/dL). Serum creatinine is 21.2 mg/dL (normal range, 0.6-1.2 mg/dL) and blood urea nitrogen is 120 mg/dL (normal range, 7-18 mg/dL). The calculated glomerular filtration rate (GFR) is 3 mL/min/1.73 m2 (normal, ≥ 90 mL/min/1.73 m2). A CT scan of the abdomen and pelvis is obtained (Figures 1 and 2).


What is the most likely diagnosis?

miércoles, 17 de agosto de 2011

EJERCICIO Y ESPERANZA DE VIDA

Quince minutos de ejercicio al día aumentan en tres años la esperanza de vida


Un estudio publicado en “The Lancet” muestra que la actividad física a niveles muy bajos reduce la mortalidad por cualquier causa en un 14%.

Las personas que practican ejercicio durante 15 minutos al día -o 92 minutos a la semana- incrementan su esperanza de vida en tres años en comparación con las personas inactivas, según un estudio publicado en The Lancet.

“El ejercicio a niveles muy bajos reduce la mortalidad por cualquier causa en un 14%”, afirma Xifeng Wu. uno de los autores principales del estudio, catedrático de la Universidad de Texas (Estados Unidos), para quien “los beneficios del ejercicio parecen ser significativos, sin llegar a la cantidad recomendada de 150 minutos por semana, basada en resultados de investigaciones previas”.

El equipo de otro de los autores principales, Chi-Pang Wen, profesor de Medicina de los Institutos Nacionales de Investigación en Salud de Taiwán , encontró que el riesgo de muerte por cualquier causa descendió en un 4% por cada 15 minutos más de ejercicio, llegando hasta los 100 minutos de ejercicio al día durante el estudio. Así, la actividad física durante 30 minutos diarios añade unos cuatro años en la esperanza de vida. “Estos beneficios son aplicables a todos los grupos de edad, de ambos sexos y a personas con riesgos de enfermedades cardiovasculares”, señalan los autores.

Según la investigación, si las personas sedentarias en Taiwán hicieran un poco ejercicio diario, una de cada seis muertes podría ser pospuesta. “Sería una reducción estimada de mortalidad similar a la de un programa de control del tabaco con éxito”, aseguran los autores.

En el estudio, que siguió a 416.175 taiwaneses entre 1996 y 2008 durante un promedio de ocho años, los participantes completaron un cuestionario sobre su historial médico y su estilo de vida, así como la actividad física que realizaron por semana durante el mes anterior, recogida por intensidad (baja, moderada o alta) y tiempo.

Asimismo, para tener en cuenta los efectos laborales, los participantes también caracterizaron la actividad física realizada en el entorno de trabajo, que va desde la actividad sedentaria al trabajo físico duro.

Los que realizaban menos de una hora a la semana de actividad física fueron clasificados como inactivos, el 54% de todos los participantes. Otros fueron clasificados en un nivel bajo, medio, alto o muy alto, sobre la base de la duración y la intensidad de su ejercicio. Los investigadores calcularon el riesgo de mortalidad y la esperanza de vida para cada grupo.

Los participantes con bajo volumen de ejercicio tenían menores tasas de mortalidad que las personas inactivas, independientemente de la edad, el riesgo de enfermedad de género, el estado de salud, el consumo de tabaco, consumo de alcohol o enfermedad cardiovascular.

Los investigadores señalan que la Organización Mundial de la Salud (OMS) y los Centros para el Control y Prevención de Enfermedades (CDC) de Estados Unidos recomiendan por lo menos 150 minutos de ejercicio de intensidad moderada por semana. Un tercio de los adultos estadounidenses cumplen con esa pauta, y alrededor del 20% de los adultos en China, Japón o Taiwán.



The Lancet 2011;doi:10.1016/S0140-6736(11)60749-6

HBAIc AS A SCREEN FOR PRE DIABETES AND DIABETES

Hemoglobina A1c as a screen for previously undiagnosed prediabetes and diabetes in an acute-care setting

  • Robert A. Silverman, MD1,
  • Urvi Thakker, DO1,
  • Tovah Ellman, MD1,
  • Ivan Wong, BS1,
  • Kelly Smith, BS1,
  • Kazuhiko Ito, PHD2 and
  • Kirsten Graff, BS1
  • +Author Affiliations

    1. 1Department of Emergency Medicine, Long Island Jewish Medical Center, North Shore–Long Island Jewish Healthcare System, Long Island, New York
    2. 2Department of Environmental Medicine, New York University School of Medicine, New York, New York
    1. Corresponding author: Robert Silverman, rsilverm@lij.edu.

    Abstract

    OBJECTIVE Hemoglobin A1c (HbA1c) is recommended for identifying diabetes and prediabetes. Because HbA1c does not fluctuate with recent eating or acute illness, it can be measured in a variety of clinical settings. Although outpatient studies identified HbA1c-screening cutoff values for diabetes and prediabetes, HbA1c-screening thresholds have not been determined for acute-care settings. Using follow-up fasting blood glucose (FBG) and the 2-h oral glucose tolerance test (OGTT) as the criterion gold standard, we determined optimal HbA1c-screening cutoffs for undiagnosed dysglycemia in the emergency-department setting.

    RESEARCH DESIGN AND METHODS This was a prospective observational study of adults aged ≥18 years with no known history of hyperglycemia presenting to an emergency department with acute illness. Outpatient FBS and 2-h OGTT were performed after recovery from the acute illness, resulting in diagnostic categorizations of prediabetes, diabetes, and dysglycemia (prediabetes or diabetes). Optimal cutoffs were determined and performance data identified for cut points.

    RESULTS A total of 618 patients were included, with a mean age of 49.7 (±14.9) years and mean HbA1c of 5.68% (±0.86). On the basis of an OGTT, the prevalence of previously undiagnosed prediabetes and diabetes was 31.9 and 10.5%, respectively. The optimal HbA1c-screening cutoff for prediabetes was 5.7% (area under the curve [AUC] = 0.659, sensitivity = 55%, and specificity = 71%), for dysglycemia 5.8% (AUC = 0.717, sensitivity = 57%, and specificity = 79%), and for diabetes 6.0% (AUC = 0.868, sensitivity = 77%, and specificity = 87%).

    CONCLUSIONS We identified HbA1c cut points to screen for prediabetes and diabetes in an emergency-department adult population. The values coincide with published outpatient study findings and suggest that an emergency-department visit provides an opportunity for HbA1c-based dysglycemia screening.

    • Received May 24, 2010.
    • Accepted June 13, 2011.