Mineral metabolism in obese patients following vertical banded gastroplasty.

BACKGROUND: Bone disease has been described in patients after surgical treatment for obesity, but few studies have dealt with the impact of vertical banded gastroplasty on mineral metabolism. We have examined bone mineral metabolism in morbidly obese patients before and after 3 months after vertical banded gastroplasty without vitamin D supplementation. METHODS: Sixteen morbidly obese patients (14 women, 2 men) with a mean (+/-SD) age of 38 +/- 9 years and a body mass index (BMI) of 47.1 +/- 8.1 kg/m2 were studied. No vitamin D supplementation was given. Body weight, fat mass, calcium, 25OHD, iPTH, bone remodeling markers, and leptin levels were measured at baseline and after weight loss. RESULTS: Mean weight loss was 28 +/- 11 kg; BMI and body fat mass decreased by 20 and 35%, respectively. Bone resorption markers and albumin-corrected serum calcium increased after operation, whereas iPTH fell. Serum 25OHD levels rose. Leptin levels decreased. Serum iPTH was positively correlated with weight, BMI, and fat mass before operation (p < 0.05), and its decline after weight reduction was negatively associated with the increase in bone resorption markers (p < 0.01). Leptin concentration was correlated with BMI and body fat mass (p < 0.05) both before and after surgery. CONCLUSIONS: Weight reduction obtained in morbidly obese subjects 3 months after vertical banded gastroplasty increases bone turnover markers and decreases PTH secretion. Serum 25OHD levels rose. Therefore, no reasons for a metabolic bone disease related to hypovitaminosis D were readily apparent. However, an increase in bone turnover, which is generally regarded as a potential risk factor for osteoporosis, was observed. Further work is needed to clarify the importance of this turnover increase in the long run.

[Electrolyte disorders following colonic cleansing for imaging studies]. / Alteraciones electrolíticas inducidas por la preparación para los estudios de imagen del colon.

BACKGROUND AND OBJECTIVE: An adequate bowel cleansing is needed prior to radiologic and endoscopic procedures. However, it may have a number of adverse effects, including abnormalities of calcium-phosphorus homeostasis. PATIENTS AND METHOD: This was an observational prospective study in a hospital practice setting. We included consecutive inpatients (n = 47) subjected to a barium enema or colon endoscopy. Prior cleansing was done as indicated by the attending physician by using a low-salt oral poliethylenglicol (PEG) solution, oral sodium phosphate or a phosphate-containing enema. RESULTS: PEG solution frequently caused mild increases in serum sodium, and decreases in serum potassium. Oral phosphate caused a significant increase in serum phosphorus and parathormone concentrations, whereas it decreased serum calcium. Mild hyperphosphatemia was found in 57% of cases, and hypocalcemia in 36%. Phosphate enema also increased serum phosphate, causing mild hyperphosphatemia (33% cases). Although in the whole subgroup of enema-treated patients there were no significant changes in serum calcium, mild hypocalcemia was found in 27% cases. CONCLUSIONS: Bowel cleansing procedures, particularly those using oral phosphate salts, frequently induce hyperphosphatemia and other abnormalities in serum electrolytes. Although usually transitory and without overt clinical consequences, clinicians should be aware of this potential risk, especially in elderly patients and those with impaired renal function.

Alteraciones electrolíticas inducidas por la preparación para los estudios de imagen del colon / Electrolyte disorders following colonic cleansing for imaging studies

Fundamento y objetivo: La limpieza intestinal es imprescindible para que los estudios de imagen del colon sean eficaces. Sin embargo, no está exenta de riesgos. En particular, recientemente se ha llamado la atención sobre la posibilidad de que ocasione alteraciones del metabolismo fosfocálcico. Este estudio se ha diseñado para evaluar sistemáticamente estas alteraciones en pacientes hospitalizados. Pacientes y método: Se ha realizado un estudio observacional prospectivo en un entorno de práctica hospitalaria habitual. Se incluyó en él a los pacientes hospitalizados consecutivos que iban a ser sometidos a un estudio endoscópico o radiológico del colon (n = 47). La preparación previa se llevó a cabo, según el criterio del médico a cargo del paciente, con uno de los 3 preparados siguientes: solución de polietilenglicol (PEG) con baja concentración de sales, fosfato sódico por vía oral (Fosfosoda®) o fosfato sódico en enemas. Resultados: La solución de PEG indujo frecuentemente hipernatremia e hipopotasemia ligeras, sin alterar la homeostasia fosfocálcica. El fosfato sódico oral provocó además un aumento significativo de la fosfatemias y un descenso de la calcemia, con un incremento compensador de la hormona paratiroidea. El 57% de los pacientes presentó valores de fósforo por encima del intervalo de referencia, mientras el 36% presentó calcemias inferiores al límite normal. El fosfato sódico en enemas no provocó cambios en las concentraciones de sodio y potasio, pero también aumentó significativamente la fosfatemia y la hormona paratiroidea. En un 33% de los casos provocó hiperfosfatemia. Aunque los cambios globales de la calcemia no fueron estadísticamente significativos, en un 27% de los pacientes que recibió enemas la concentración de calcio se redujo por debajo del límite inferior de la normalidad. Conclusiones: Las preparaciones de limpieza intestinal, en particular las basadas en el fosfato oral, se asocian frecuentemente a alteraciones electrolíticas. Aunque en general son autolimitadas y sin repercusión clínica, estas complicaciones deben tenerse en cuenta en pacientes de riesgo, como los ancianos y los que presentan insuficiencia renal

Background and objective: An adequate bowel cleansing is needed prior to radiologic and endoscopic procedures. However, it may have a number of adverse effects, including abnormalities of calcium-phosphorus homeostasis. Patients and method: This was an observational prospective study in a hospital practice setting. We included consecutive inpatients (n = 47) subjected to a barium enema or colon endoscopy. Prior cleansing was done as indicated by the attending physician by using a low-salt oral poliethylenglicol (PEG) solution, oral sodium phosphate or a phosphate-containing enema. Results: PEG solution frequently caused mild increases in serum sodium, and decreases in serum potassium. Oral phosphate caused a significant increase in serum phosphorus and parathormone concentrations, whereas it decreased serum calcium. Mild hyperphosphatemia was found in 57% of cases, and hypocalcemia in 36%. Phosphate enema also increased serum phosphate, causing mild hyperphosphatemia (33% cases). Although in the whole subgroup of enema-treated patients there were no significant changes in serum calcium, mild hypocalcemia was found in 27% cases. Conclusions: Bowel cleansing procedures, particularly those using oral phosphate salts, frequently induce hyperphosphatemia and other abnormalities in serum electrolytes. Although usually transitory and without overt clinical consequences, clinicians should be aware of this potential risk, especially in elderly patients and those with impaired renal function