[Diabetic neuropathy. Current concepts on etiopathogenesis, diagnosis, and treatment]. / Neuropatía diabética. Conceptos actuales sobre etiopatogénesis, diagnóstico y tratamiento.

Diabetic neuropathy (DN) is chronic complication which occurs in 50% of long standing diabetes mellitus. DN is a consequence of hyperglycemia probably through the following mechanisms: a) activation of aldose-reductase, intracellular sorbitol accumulation and myoinositol depletion, reduced activity of Na+/K+ATPase, loss of Na+ channels and demyelination; b) proteins glycation; c) microangiopathy; the first mechanism being the best known and the most reliable. DN may be subclinical or clinical. The main clinical picture is a peripheral, bilateral, symmetric polyneuropathy with a "socks and gloves" sensory impairment, muscular weakness, hyporeflexia, plantar ulcers and arthropathy. Less frequent syndromes are proximal motor neuropathy and mononeuropathy of cranial nerves or thoraco-abdominal roots. Diagnosis is based on clinical data, and may be sustained on impaired nerve conduction velocity, abnormal evoked somatosensory potentials, or sural nerve biopsy. These methods are highly sensitive but unspecific. Etiopathogenic treatment is based on glycemic control and aldose reductase inhibitors. Improvement in clinical, electrophysiologic and histopathologic data have been obtained with the latter. Symptomatic treatment includes carbamazepin, phenytoin, tricyclic antidepressives and a phenotiazin. Mononeuropathies tend to complete recovery in less than 6 months. Polyneuropathy is thought to be irreversible and progressive; however, with excellent glycemic control or with aldose reductase inhibitors nerve damage may be stabilized or even reversed.

Hiperlipidemia familiar combinada.Estudio de una familia. / Combined familial hyperlipidemia. Study of a family

Se estudiaron 15 miembros de una familia con hiperlipidemia familiar combinada, en los que observamos las caracteristicas clinicas principales de este trastorno. El analisis del pedigree y los valores de colesterol y trigilceridos permiten postular un mecanismo de transmision autosomico dominante. El 50 de los individuos de la generacion de los probandos demonstraron valores de lipidos diagnosticos de hiperlipidemia. En base a los valores absolutos de colesterol y trigiceridos, asi como a la electroforesis de lipoproteinas en suero se diagnosticaron los patrones de Fredrickson IIa, IIb, y IV, con una frecuencia similar, de aproximadamente 33% para cada uno de los fenotipos entre los individuos afectados.Los valores medios de colesterol y trigliceridos ajustados para edad y sexo entre los miembros hiperlipidemicos fueron de 308.9 mg/dl (> P95) y 252.1 mg/dl (> P90) respectivamente, mientras que en los casos no afectados correspondieron a 212.1 mg/dl (< P50) para colesterol y 124.9 mg/dl (< P50) para trigliceridos. Se observo claramente en esta familia la existencia de cardiopatia ateroesclerosa prematura, incluyendo 3 casos de muerte a edad temprana por infarto miocardico