Propylthiouracil

About: Propylthiouracil is a research topic. Over the lifetime, 2181 publications have been published within this topic receiving 46996 citations. The topic is also known as: Thyreostat® & 2,3-dihydro-6-propyl-2-thioxo-4(1H)-pyrimidinone.

Propylthiouracil-induced rapidly progressive glomerulonephritis associated with antineutrophil cytoplasmic autoantibodies.

Abstract: We present a case study of a 52-year-old female patient with hyperthyroidism which had been diagnosed at the age of 35. However, the malfunction of thyroid had been poorly controlled. Thyroid function was returning to normal after the administration of propylthiouracil (PTU) 300 mg/day, however purpura appeared in both lower extremities. Renal function deteriorated rapidly, and the patient was admitted to our hospital. According to the biopsies, leukocytoclastic vasculitis in the skin was apparent, and crescent formation was observed in the glomerulus. Serological examination revealed positive antineutrophil cytoplasmic autoantibodies (ANCA) against proteinase 3 (Pr3) and myeloperoxidase (MPO). Antinuclear autoantibody was positive. After cessation of PTU and administration of prednisolone, the purpura disappeared and ANCA were becoming negative. Renal function recovered gradually. Thyroid function was kept within normal range using iodine solution. Thus, it is strongly suggested that PTU-induced rapidly progressive glomerulonephritis associated with ANCA.

Expression of 5'-deiodinase enzymes in normal pituitaries and in various human pituitary adenomas

Abstract: Objective: Local 5 0 -deiodination of L-thyroxine (T4) to active thyroid hormone 3,3 0 ,5-tri-iodothyronine (T3) catalyzed by the two 5 0 -deiodinase enzymes (D1 and D2) regulates various T3-dependent functions in the anterior pituitary and has been well studied in rodents. Only limited information about deiodinase expression and its cellular distribution in human anterior pituitaries is available. Design: We examined 5 0 -deiodinase enzyme activities in pituitary adenomas (18 non-functioning, seven TSH-producing, one GH- and TSH-producing, five GH-producing, eight prolactin (PRL)-producing, two adenomas each from patients with Cushing’s disease and Nelson’s syndrome) and three normal anterior pituitaries. Methods: Activities were measured as release of 125 I 2 from tyrosyl-ring labeled reverse T3 with or without propylthiouracil, a potent inhibitor of D1 which does not influence D2 activities. Results: Most of the adenomas and normal tissues expressed both isoenzymes, with D2 activity higher than D1. In a few tissues D1 activity was higher than D2 and some tissues did not express D1 activity at all. Highest activities of both enzymes were found in TSH- and PRL-producing adenomas but absolute activities and the D1/D2 ratio were variable in the same kind of tumor in different patients. Conclusion: The finding that all examined tissues expressed 5 0 -deiodinase activity, most of them expressing both isoenzymes, implies that both enzymes are still active in tumors and that local deiodination is important for the function and feedback regulation of human anterior pituitary.

Thyroid disease in pregnancy and childhood.

Abstract: The subject of thyroid disease in pregnancy is receiving increasing attention from many scientific disciplines. Thyroid function in pregnancy is characterised by a T4 surge at 12 weeks declining thereafter. Serum thyroid hormone concentrations fall in the second half of pregnancy but there are few data on normal reference ranges. Fetal brain development depends on T4 transport into the fetus which in turn depends on sufficient maternal iodine supply. There is current concern that adequate iodisation is not present in large parts of Europe. There is increasing evidence that thyroid autoimmunity is associated with fetal loss but the mechanism is unclear and therapy requires carefully conducted studies. While hyperthyroidism in pregnancy is uncommon, effects on both mother and child are critical if untreated. The use of propylthiouracil is recommended together with measurement of TSH receptor antibodies at 36 weeks gestation. Women receiving thyroxine therapy for hypothyroidism or as suppressive therapy should have their dose increased by up to 50% during pregnancy. There are now substantial data to show deleterious effects on child IQ resulting from low maternal T4 (or high TSH) during gestation. Major advances in molecular biology have contributed to elucidation of many genetic causes of congenital hypothyroidism. However, the aetiology of the majority of cases is still unclear and further research is required. The presence of TPO antibodies in about 10% of pregnant women in early gestation is a predictor of an increased incidence of subclinical hypothyroidism during pregnancy and also of postpartum thyroid dysfunction. The latter condition occurs in 5-9% of women and 25-30% progress to permanent hypothyroidism. This review suggests that screening for thyroid function in early pregnancy and levothyroxine intervention therapy for maternal subclinical hypothyroidism should be considered but evidence is awaited. Screening for both thyroid dysfunction and thyroid antibodies ideally at a preconception clinic but certainly in early gestation is recommended.

Propylthiouracil hepatotoxicity: two pediatric cases and review of the literature.

Abstract: We have observed isolated hepatotoxicity in two children treated with propylthiouracil (PTU) for hyperthyroidism. Neither patient had risk factors for or clinical evidence of preexisting liver disease. In one patient the drug was promptly discontinued when signs of liver disease were noted. This patient quickly recovered. The second patient continued to receive PTU for several days after developing symptoms. Her illness progressed to fulminant hepatic failure with encephalopathy, and she died. These are the third and fourth pediatric cases reported, and there have been 10 cases reported in adults in the English language literature. Thirteen of the 14 patients are female. The literature regarding all these patients is reviewed. Propylthiouracil may cause lethal hepatic damage. This drug should be discontinued immediately if signs or symptoms of hepatic injury are detected.

Thyroid Function and Insulin Secretion from the Perfused Pancreas in the Rat

Abstract: The influence of thyroid function on the kinetics of glucose-induced insulin secretion from theisolated perfused rat pancreas has been studied. L-Thyroxine (L-T4) administration did not modify the immediate insulin secretory response of the perfused pancreas to glucose. L-Triiodothyronine(L-T3) treatment as well as propylthiouracil (PTU)treatment decreased the immediate insulin secretory response of the pancreas slightly. Only thyroidectomy(Tx) reduced the immediate secretory response of the pancreas significantly. L-T4and L-T3 treatmentinhibited the late phase of glucose-induced insulin secretion from the isolated perfused rat pancreas, whereas Tx and PTU treatment resulted in increased insulin secretion. D-Thyroxine (D-T4) did not affect glucose-induced insulin release from the pancreas. Concomitantly, several parameters indicative of thyroid function were determined in these animals. When changes in body weight, rectal temperature,plasma glucose, plasma cholesterol, and plasmabutanol-extractable iodine...