Phenotypic characterization of X-linked hypophosphatemia in pediatric Spanish population.

BACKGROUND: X-linked hypophosphatemia (XLH) is a hereditary rare disease caused by loss-of-function mutations in PHEX gene leading tohypophosphatemia and high renal loss of phosphate. Rickets and growth retardation are the major manifestations of XLH in children, but there is a broad phenotypic variability. Few publications have reported large series of patients. Current data on the clinical spectrum of the disease, the correlation with the underlying gene mutations, and the long-term outcome of patients on conventional treatment are needed, particularly because of the recent availability of new specific medications to treat XLH. RESULTS: The RenalTube database was used to retrospectively analyze 48 Spanish patients (15 men) from 39 different families, ranging from 3 months to 8 years and 2 months of age at the time of diagnosis (median age of 2.0 years), and with XLH confirmed by genetic analysis. Bone deformities, radiological signs of active rickets and growth retardation were the most common findings at diagnosis. Mean (± SEM) height was - 1.89 ± 0.19 SDS and 55% (22/40) of patients had height SDS below-2. All cases had hypophosphatemia, serum phosphate being - 2.81 ± 0.11 SDS. Clinical manifestations and severity of the disease were similar in both genders. No genotype-phenotype correlation was found. Conventional treatment did not attenuate growth retardation after a median follow up of 7.42 years (IQR = 11.26; n = 26 patients) and failed to normalize serum concentrations of phosphate. Eleven patients had mild hyperparathyroidism and 8 patients nephrocalcinosis. CONCLUSIONS: This study shows that growth retardation and rickets were the most prevalent clinical manifestations at diagnosis in a large series of Spanish pediatric patients with XLH confirmed by mutations in the PHEX gene. Traditional treatment with phosphate and vitamin D supplements did not improve height or corrected hypophosphatemia and was associated with a risk of hyperparathyroidism and nephrocalcinosis. The severity of the disease was similar in males and females.

The influence of clinical situation on health-related quality of life in paediatric chronic kidney disease patients.

BACKGROUND: Studies examining health-related quality of life (HRQOL) in adults with chronic kidney disease (CKD) have demonstrated that certain clinical situations such as number of hospitalisations and anaemia can affect patient quality of life. Very few such studies have been carried out in children. OBJECTIVE: To analyse the impact of laboratory variables and various clinical situations on HRQOL of paediatric CKD patients. PATIENTS AND METHOD: We carried out a cross-sectional study using the TECAVNER questionnaire in 71 children with CKD and their parents (33 transplanted patients, 11 on peritoneal dialysis, 5 on haemodialysis, and 22 on conservative treatment). We analysed laboratory variables (blood urea nitrogen, creatinine, haematocrit, and albumin), clinical situation (short stature, arterial hypertension, and bone deformities), number of hospitalisations, and days spent in the hospital in the previous 6 months, as well as number of drugs administered and fluids/diet restrictions. RESULTS: The factor that most heavily affected the quality of life of our patients was water restrictions. In addition, hypertension affected cognitive function in these children. A haematocrit value >35% improved physical activity and functionality. We observed no association between albumin and HRQOL. CONCLUSIONS: These results confirm previous hypotheses and contribute to the validity of the TECAVNER questionnaire.

Influencia de la situación clínica en la calidad de vida relacionada con la salud de los pacientes pediátricos con enfermedad renal crónica / The influence of clinical situation on health-related quality of life in paediatric chronic kidney disease patients

Antecedentes: Estudios sobre la calidad de vida relacionada con la salud (CVRS) en adultos con enfermedad renal crónica (ERC) han demostrado que situaciones clínicas como el número de ingresos o la anemia afectan a su calidad de vida. Existen muy pocos estudios similares en niños. Objetivo: Analizar el impacto de variables analíticas y de la situación clínica en la CVRS de los pacientes pediátricos con ERC. Pacientes y métodos: Estudio transversal utilizando el cuestionario TECAVNER en 71 niños con ERC y en sus padres (33 trasplantados, 11 en diálisis peritoneal, 5 en hemodiálisis, 22 en tratamiento conservador). Se analizaron variables analíticas (nitrógeno ureico en sangre, creatinina, hematocrito, albúmina) y situación clínica (talla baja, hipertensión arterial [HTA], deformidades óseas), número de ingresos y días de ingreso en los seis meses previos a la realización del estudio, así como número de fármacos administrados, restricción de líquidos o dieta. Resultados: uno de los factores que más distorsiona la calidad de vida de nuestros pacientes es la restricción hídrica. La HTA afecta a la función cognitiva de los niños. El hematocrito superior a un 35 % mejora la función y la actividad física. No encontramos relación entre valores de albúmina y CVRS. Conclusiones: Estos resultados confirman las hipótesis previas y contribuyen a dar validez al cuestionario TECAVNER (AU)

Background: Studies examining health-related quality of life (HRQOL) in adults with chronic kidney disease (CKD) have demonstrated that certain clinical situations such as number of hospitalisations and anaemia can affect patient quality of life. Very few such studies have been carried out in children. Objective: To analyse the impact of laboratory variables and various clinical situations on HRQOL of paediatric CKD patients. Patients and Method: We carried out a cross-sectional study using the TECAVNER questionnaire in 71 children with CKD and their parents (33 transplanted patients, 11 on peritoneal dialysis, 5 on haemodialysis, and 22 on conservative treatment). We analysed laboratory variables (blood urea nitrogen, creatinine, haematocrit, and albumin), clinical situation (short stature, arterial hypertension, and bone deformities), number of hospitalisations, and days spent in the hospital in the previous 6 months, as well as number of drugs administered and fluids/diet restrictions. Results: The factor that most heavily affected the quality of life of our patients was water restrictions. In addition, AHT affected cognitive function in these children. A haematocrit value >35% improved physical activity and functionality. We observed no association between albumin and HRQOL. Conclusions: These results confirm previous hypotheses and contribute to the validity of the TECAVNER questionnaire (AU)