RESUMEN
The purpose of this work is to describe a first approach to a smart bioimpedance spectroscopy device for its application to the estimation of body composition. The proposed device is capable of carrying out bioimpedance measurements in multiple configurable frequencies, processing the data to obtain the modulus and the bioimpedance phase in each of the frequencies, and transmitting the processed information wirelessly. Another novelty of this work is a new algorithm for the identification of Cole model parameters, which is the basis of body composition estimation through bioimpedance spectroscopy analysis. Against other proposals, the main advantages of the proposed method are its robustness against parasitic effects by employing an extended version of Cole model with phase delay and three dispersions, its simplicity and low computational load. The results obtained in a validation study with respiratory patients show the accuracy and feasibility of the proposed technology for bioimpedance measurements. The precision and validity of the algorithm was also proven in a validation study with peritoneal dialysis patients. The proposed method was the most accurate compared with other existing algorithms. Moreover, in those cases affected by parasitic effects the proposed algorithm provided better approximations to the bioimpedance values than a reference device.
Asunto(s)
Composición Corporal , Monitoreo Fisiológico/métodos , Algoritmos , Antropometría , Estatura , Índice de Masa Corporal , Peso Corporal , Espectroscopía Dieléctrica , Impedancia Eléctrica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/instrumentación , Programas InformáticosRESUMEN
The finding of persistent hypercalcemia suggests doing other medical tests to find the cause. Familial hypocalciuric hypercalcemia is usually benign and it requires no treatment. It is important to do CASR gene sequencing to avoid unnecessary treatments. We report a 12-year-old child, asymptomatic, with calcemia between 11.4 and 12.2 mg/dl. His father and two brothers presented asymptomatic hypercalcemia. The blood test with magnesium, phosphorus, 25(OH)Vit D was normal, remarkable normal parathyroid hormone for the level of hypercalcemia. Urinary calcium/creatinine ratio was 0,11 mg/dl and 24-hour urinary calcium was 1,8 mg/kg per day. Abdominal and parathyroid ecography, long bone radiographs and densitometry were normal. Genetic study showed a mutation, c.1651A>G, in exon 6 of the calciumsensing receptor gene, confirmed in father and brothers, too.
La presencia de hipercalcemia mantenida obliga a realizar pruebas complementarias para determinar su origen. Es benigna y, generalmente, no requiere tratamiento. La secuenciación del gen CaSR confirma el diagnóstico y evita tratamientos innecesarios. Se presenta a un niño de 12 años, asintomático, con hipercalcemia persistente entre 11,4 y 12,2 mg/dl. El padre y dos hermanos tenían hipercalcemia asintomática. El análisis de laboratorio mostró valores de magnesio, fósforo y vitamina D normales y de hormona paratiroidea llamativamente normal para el valor de la hipercalcemia. Indice de calcio/creatinina urinario: 0,11 mg/mg; y calciuria de 24 h: 1,8 mg/kg/día. Ecografía abdominal, paratiroides, radiografías de huesos largos y densitometría ósea, normales. El estudio genético mostró mutación en exón 6 (c.1651A>G) del gen CaSR (en heterocigosis), confirmada en el padre y los hermanos.
Asunto(s)
Hipercalcemia/congénito , Hipercalcemia/etiología , Receptores Sensibles al Calcio/genética , Niño , Exones , Humanos , Hipercalcemia/diagnóstico , Hipercalcemia/genética , Masculino , MutaciónRESUMEN
La presencia de hipercalcemia mantenida obliga a realizar pruebas complementarias para determinar su origen. Es benigna y, generalmente, no requiere tratamiento. La secuenciación del gen CaSR confirma el diagnóstico y evita tratamientos innecesarios. Se presenta a un niño de 12 años, asintomático, con hipercalcemia persistente entre 11,4 y 12,2 mg/dl. El padre y dos hermanos tenían hipercalcemia asintomática. El análisis de laboratorio mostró valores de magnesio, fósforo y vitamina D normales y de hormona paratiroidea llamativamente normal para el valor de la hipercalcemia. Indice de calcio/creatinina urinario: 0,11 mg/mg; y calciuria de 24 h: 1,8 mg/kg/día. Ecografía abdominal, paratiroides, radiografías de huesos largos y densitometría ósea, normales. El estudio genético mostró mutación en exón 6 (c.1651A>G) del gen CaSR (en heterocigosis), confirmada en el padre y los hermanos.
The finding of persistent hypercalcemia suggests doing other medical tests to find the cause. Familial hypocalciuric hypercalcemia is usually benign and it requires no treatment. It is important to do CASR gene sequencing to avoid unnecessary treatments. We report a 12-year-old child, asymptomatic, with calcemia between 11.4 and 12.2 mg/dl. His father and two brothers presented asymptomatic hypercalcemia. The blood test with magnesium, phosphorus, 25(OH)Vit D was normal, remarkable normal parathyroid hormone for the level of hypercalcemia. Urinary calcium/creatinine ratio was 0,11 mg/dl and 24-hour urinary calcium was 1,8 mg/kg per day. Abdominal and parathyroid ecography, long bone radiographs and densitometry were normal. Genetic study showed a mutation, c.1651A>G, in exon 6 of the calciumsensing receptor gene, confirmed in father and brothers, too.