Función β celular en prediabetes tipo 2. Eficacia terapéutica en prediabetes: opciones de preservación de célula beta

La evolución del islote de Langerhans, y dentro de éste del pool celular β desde la normalidad hasta la diabetes mellitus tipo 2 (DM2), pasa por diferentes momentos dentro de los que pueden observarse la hiperplasia adaptativa inicial a la insulinorresistencia y su posterior claudicación con una reducción de la masa celular mayor al 50%, aumento de las células α, fibrosis y aparición de depósitos amiloides1. Entre estos dos períodos, se detecta uno intermedio, correspondiente al que clínicamente se manifiesta como prediabetes (PDM2), en el que ya existen alteraciones en la dinámica de secreción normal de la insulina, con pérdida de su primer pico2.Para prevenir la progresión desde la PDM2 a la DM2, se plantean diferentes estrategias terapéuticas:• Monitorizar anualmente a estas personas ante el posible desarrollo de DM2 (E*).• Incorporarlas a programas de cambios en el estilo de vida (CEV) para lograr y mantener una pérdida del peso corporal de al menos el 7% (A).• Incorporarlas a rutinas de actividad física de al menos 150 minutos semanales de caminata enérgica (A).• Con planes de alimentación adecuados (B).• Utilizando programas de asistencia a través de aplicaciones (B).Dado su costo-efectividad (A), todos estos programas deberían ser costeados por el sistema de salud3.Se encontró que, aún sin pérdida de peso, 150 minutos semanales de actividad física (700 kcal/semana) redujeron la incidencia de DM2 en un 44%; también que, si bien un 7% de la pérdida de peso corporal es suficiente para disminuir la incidencia de DM2, los resultados son mejores reduciendo un 10%. Se estimó necesaria una pérdida de peso de entre 0,5 y 1 Kg/semana, con una restricción calórica de entre 500 y 1000 calorías/día, no habiendo un patrón definido respecto de la composición de la dieta para lograr este objetivo4.Dado que los CEV son difíciles de lograr o mantener, se puede considerar el uso de fármacos. Aquellos que demostraron efectividad en estudios aleatorizados prospectivos son: acarbosa, liraglutida, rosiglitazona, pioglitazona, glargina, orlistat, fentermina más topiramato y metformina.La metformina es la recomendada por la American Diabetes Association3 y ésta más acarbosa por la American Association of Clinical Endocrinologist and American College of Endocrinology sumando, de existir PDM2 con más de un criterio diagnóstico, TZD y/o a-GLP1. Debe tenerse en cuenta que, sumado a los CEV, con el objeto de disminuir el peso, se puede agregar medicación u otras terapias como la cirugía bariátrica5.* Nivel de evidencia

Incidental detection of a rare hemoglobin variant (Hemoglobin N Seattle) leading to undetectable levels of HbA1c in a diabetic female: a case report

<p>Glycosylated hemoglobin (GHb) is routinely used to monitor glycemic control over past 2-3 months in diabetics. As per the recommendations of the American Association of Clinical Endocrinologist, 2007 values should be maintained below 7% to prevent the risk of chronic complications. We report a case of a 55-year old female patient with spuriously low HbA1c values by high-performance liquid chromatography. Suspecting the presence of any abnormal hemoglobin, capillary zone electrophoresis was done which identified the presence of Hb variant corresponding to -Hb N Seattle. Our case highlights that clinical laboratories should be aware of limitations of their HbA1c assay methods as well as rule out any possible interfering Hb variants.</p><p> </p><p>糖化血红蛋白(GHB)在糖尿病方面被常规用于监测过去2-3个月血糖控制。 根据美国临床内分泌医师学会2007年的建议，这个值应该被维持在7%以下，以防止慢性并发症的风险。 我们报告了一例55岁女性患者使用高效液体相色谱法测定假性低HbA1c值的病例。 因怀疑存在有某种异常血红蛋白，我们进行了毛细血管区带电泳，识别出存在对应于-Hb N Seattle的Hb变异体。 我们的病例强调了临床实验室应该意识到其HbA1c测定方法的局限性，并排除任何可能引起干扰的Hb变异体。</p>

Measurement of hormones

The role of accurate and reliable laboratory testing is particularly important for patients with potential endocrine disorders. The revolution which has taken place in the past 50 years in the methodology of hormone measurement is thus of considerable significance to this patient group. It is difficult to imagine that not too long ago common hormone measurements, such as thyroid function tests, took more than a week to produce. Now we live in a world where same day turnaround is the norm for the high throughput commonly requested tests. This is largely due to advances in the way hormones are measured and results delivered to the practising clinical endocrinologist. Measuring hormones has always been a challenge as most circulate at extremely low concentrations, typically in the pico- (10–12) or nanomolar (10–9) range, and often in a milieu of closely related and potentially interfering compounds making great demands on method sensitivity and specificity. The most common procedures currently used are immuno- and immunometric assays but gas chromatography mass spectrometry (GCMS) and high-performance liquid chromatography (HPLC) also have a place. Liquid chromatography mass spectrometry (LC-MS/MS) is rapidly gaining acceptance for a limited number of hormone measurements. It is not the aim of this chapter to provide precise detail on hormone measurement methodology but rather to overview general principles and applications of methods in current use. Attention is drawn to preanalytical and analytical problems which could have significant clinical consequences if not recognized.

Endocrinology: the next 60 years

Advances in clinical chemistry, molecular biology and information technology have brought about major changes in the field of endocrinology. The future practice of endocrinology will be influenced by secular health trends, consumer expectations and the globalisation of health. Pharmacotherapy will remain the backbone of endocrine therapy led by developments in drug delivery technology, pharmacogenomics, combinatorial chemistry and paracrinology. The endocrine-related consequences of obesity and ageing will be major health problems, demand for anti-obesity and anti-ageing treatments will escalate. There will be increased blurring between endocrine disease and non-disease. The future clinical endocrinologist must continue to practice evidence-based medicine to improve the treatment of genuine endocrinopathies.