Dados do Trabalho

Título

Serum levels of Fibroblast Growth Factor-23 in Hypoparathyroidism

Fundamentação/Introdução

Hypoparathyroidism (HP) is a rare endocrine disease, characterized by low serum calcium levels, hyperphosphatemia and absence or inappropriately low serum levels of PTH (6,7). In hypoparathyroidism, the lack of PTH leads to hyperphosphatemia (9). One would expect, but it is not known, whether the hyperphosphatemia due to lack of PTH in hypoparathyroidism is a biochemical signal to stimulate FGF 23 production and reduce serum phosphorus levels. Both hormones interact, and an important physiological function of FGF23 may be to enable normal responsiveness to PTH signaling in the kidney. Just a few studies have measured FGF23 in patients with hypoparathyroidism. It was demonstrated that a reduction in PTH signaling in human patients with hypoparathyroidism has been shown to induce partial resistance to the phosphaturic actions of FGF23.

Objetivos

To address this point, we conducted a study to evaluate serum levels of FGF23 in patients with hypoparathyroidism. . In addition, we sought to compare FGF23 levels between the two major etiologies of hypoparathyroidism, postsurgical and autoimmune

Delineamento e Métodos

Patients diagnosed with HP by the co-presence of hypocalcemia and low PTH or by inappropriately low calcium levels with inappropriate normal PTH. were recruited from the bone metabolism outpatient clinic of Endocrinology Division of the Federal University of Paraná. An extensive chart review of clinical data, laboratory and treatment was performed and has been published elsewhere (10). Subsequently, patients were asked to participate in this study and after written informed consent they had their blood taken. The study was approved by the local Ethical Committee

Resultados

From a total of 50 patients with HP, 24 had FGF23 levels measured. In this cohort, 80% were women, mean age of 46.9 ± 18.4 years old and mean disease duration of 11.6 ± 7.7 years (isso se refere nso aos que mediram o FGF?). Talvez estes 24 pacientes devessem ser melhor explicados digo as caracteristicas clíncas. Anterior neck surgery was the cause of the HP in 82% of patients and the others had evidence for autoimmune disease. The average dose of calcium carbonate was 1255 ± 453 mg/day; calcitriol 0.67 ± 0.38 mcg/day; and vitamin D3 35,5 ± 20,3 U/week. No difference in treatment doses was observed among the two etiologies.

Conclusões/Considerações finais

This study has explored FGF23 levels in the context of exceedingly low or undetectable levels of PTH.

Palavras-chave

FGF 23, PTH hipoparatireoidismo

Área

Clínica Médica