oxalates and Hypothyroidism

Primary hyperoxaluria (PH) is a rare genetic disorder characterized by overproduction of oxalate due to specific enzyme deficiencies in glyoxylate metabolism. The primary clinical presentation is in the form of recurrent urolithiasis, progressive nephrocalcinosis, end-stage renal disease, and systemic oxalosis. Herein, we present a case of PH who was diagnosed at 47 years of age after 6 years on hemodialysis. He presented with fatigue, anorexia, weight loss, and was found to have cachexia, diffuse edema, hepatomegaly, ascites, hypercalcemia, hyperphosphatemia, hypoalbuminemia, low parathyroid hormone levels, lytic and resorptive areas in the vertebrae, diffusely increased echogenity of the liver, multiple renal stones, and bilateral nephrocalcinosis. Bone marrow biopsy showed calcium oxalate crystals and crystal granulomas. The liver biopsy could not be performed. The absence of an identifiable reason for secondary forms, the severity of the clinical presentation, and pathological findings led to the diagnosis of PH2. He died while waiting for a potential liver and kidney donor. The presented case is consistent with the literature as he had renal stone disease in the third decade and end-stage renal disease in the fifth decade. Hypercalcemia was thought to be due to osteoclast-stimulating activity of macrophages constituting the granuloma. Erythropoietin-resistant anemia and hypothyroidism were thought to be due to accumulation of oxalate in the bone marrow and thyroid gland, respectively. It is very important to keep in mind the possibility of PH when faced with a patient with nephrocalcinosis and oxalate stone disease.

Topics: Ascites; Bone Marrow; Granuloma; Hepatomegaly; Humans; Hypercalcemia; Hyperoxaluria, Primary; Hypothyroidism; Kidney Failure, Chronic; Male; Middle Aged; Nephrocalcinosis; Oxalates; Renal Dialysis; Urolithiasis

The effects of hypothyroidism on the Ca2+-transport capabilities of fast-twitch muscle (m. gastrocnemius) of the rat were studied in whole-muscle homogenate and isolated sarcoplasmic reticulum. Hypothyroidism did not affect the percentage recovery and the vesicle composition of the sarcoplasmic reticulum fraction, the total lipid and phospholipid-to-protein ratios and the protein composition (both qualitative and quantitative). Also the Ca2+-loading capacity of purified sarcoplasmic reticulum, in the presence of oxalate, and the Ca2+ and pH dependence of both the uptake reaction and the coupled ATPase activity were unchanged. However, the homogenate Ca2+-loading capacity and the Ca2+-uptake activity were depressed, as was the yield of purified sarcoplasmic reticulum. The results indicate a 31% reduction of the entire sarcoplasmic reticulum membrane system per volume of muscle. Ca2+/ATP coupling ratios, determined in purified sarcoplasmic reticulum vesicles by measurement of initial rates of net Ca2+ uptake and Ca2+-Mg2+-dependent hydrolysis of ATP, were found to be 1.48 +/- 0.06 and 2.08 +/- 0.05 in the euthyroid and hypothyroid groups, respectively. Identical values were obtained with a recently described Ca2+-pulse method (Meltzer, S. and Berman, M.C. (1984) Anal. Biochem. 138, 458-464), i.e., 1.53 +/- 0.06 and 2.01 +/- 0.03 in the euthyroid and hypothyroid groups, respectively. Passive Ca2+ efflux from sarcoplasmic reticulum was the same in both groups (30 nmol/mg per min), as was the fraction of vesicles that did not show net uptake of Ca2+ (less than 10%), which makes it unlikely that these parameters provide an explanation for the differences in the coupling ratio. The energy of activation of the (Ca2+ + Mg2+)-ATPase was increased in hypothyroidism, which may point to changes in the phospholipid environment of the enzyme. Physiological concentrations of T3 and T4 had no effect on the (Ca2+ + Mg2+)-ATPase in vitro, but all observed changes in the hypothyroid state could be reversed within 14 days by administration of T3 to hypothyroid animals. Approximate calculations indicate that the observed changes in the sarcoplasmic reticulum as a result of thyroid-hormone depletion may contribute significantly to the decrease in relaxation rate and the decrease in energy consumption during contraction.

Topics: Animals; Biological Transport, Active; Ca(2+) Mg(2+)-ATPase; Calcium; Calcium-Transporting ATPases; Energy Metabolism; Hypothyroidism; Kinetics; Male; Muscle Contraction; Muscle Proteins; Muscle Relaxation; Muscles; Oxalates; Oxalic Acid; Oxygen Consumption; Rats; Rats, Inbred Strains; Sarcoplasmic Reticulum; Temperature; Triiodothyronine

In this chemiluminescence enzyme immunoassay for thyroxin, glucose oxidase (EC 1.1.3.4) is the enzyme label and the bound and free fractions are separated by the double-antibody solid-phase technique. In the assay of enzyme activity, hydrogen peroxide generated from glucose substrate is measured by its chemiluminescence reaction with bis(2,4,6-trichlorophenyl)oxalate and 8-anilino-1-naphthalene-sulfonic acid. The measurable range of thyroxin is 2.5 to 200 micrograms/L. The coefficients of variation for thyroxin concentrations of 43.2 and 12.8 micrograms/L were 7.0% and 8.6% (intra-assay), and 6.4% and 12.3% (interassay), respectively. The proposed method is applicable to large-scale preliminary screening of neonates for congenital hypothyroidism, with samples consisting of dried blood spotted on filter paper.

Topics: Congenital Hypothyroidism; Fluorescent Dyes; Glucose Oxidase; Humans; Hypothyroidism; Immunoenzyme Techniques; Infant, Newborn; Luminescent Measurements; Mass Screening; Oxalates; Radioimmunoassay; Thyroxine

Topics: Animals; Body Weight; Female; Hypothyroidism; Iodine; Male; Monoiodotyrosine; Oxalates; Rats; Sex Factors; Thyroid Gland; Thyrotropin; Thyroxine; Triiodothyronine

1. Cardiac sarcoplasmic reticulum (SR) was prepared by differential centrifugation from euthyroid, hyperthyroid, hypothyroid as well as (131)I-treated plus thyroxine-substituted rabbits. The function of the isolated SR has been characterized by measuring the ATP-dependent calcium uptake, the calcium storing capacity, the calcium concentrating ability and the calcium-dependent ATP hydrolysis by the calcium-activated ATPase in the presence of oxalate.2. The rate of calcium uptake and the rate of the calcium-dependent ATP hydrolysis (calcium-activated ATPase) by the SR were significantly increased in hyperthyroidism, whilst both activities were markedly reduced in hypothyroidism. Thyroxine administration to (131)I-treated animals prevented a decrease in the rate of calcium uptake as well as in the rate of the calcium-dependent ATP hydrolysis by the calcium-activated ATPase.3. The transport ratio (rate of calcium uptake divided by the rate of calcium-dependent ATP hydrolysis) of SR preparations from euthyroid controls was 0.93, suggesting a stoicheiometry of calcium uptake and calcium-activated ATP split of 1.0. The transport ratio was unchanged in one hyper- and hypothyroid group, whilst a small but significant decrease or increase was observed after an excessive thyroxine treatment of a prolonged state of hypothyroidism, respectively.4. The saturation kinetics of calcium transport by the SR were described by Michaelis-Menten kinetics. The maximum rate of calcium uptake (V) was 0.193+/-0.004, 0.223+/-0.002 and 0.124+/-0.003 mumole Ca(2+)/mg protein. min (means +/-S.E.) for euthyroid, hyperthyroid and hypothyroid SR, respectively. The Michaelis constants (K(m)) were (2.87+/-0.30) x 10(-7)M (2.68+/-0.15) x 10(-7)M and (4.00+/-0.48) x 10(-7)M for the euthyroid, hyperthyroid and hypothyroid SR, respectively (means +/-S.E.). The K(m) values for the hyper- and hypothyroid SR were not significantly different from controls.5. The calcium storing capacity as well as the calcium concentrating ability of the SR was unaltered at different levels of thyroid activity.6. The steady-state level of calcium was the same for SR isolated from euthyroid, hyperthyroid and hypothyroid rabbits, indicating that calcium influx and calcium efflux are strongly coupled at steady-state filling of the SR.7. It is suggested that the increased or reduced rate of calcium transport by the SR in hyperthyroidism or hypothyroidism, respectively, found in vitro, might be at least partially respon

Topics: Adenosine Triphosphatases; Adenosine Triphosphate; Animals; Biological Transport, Active; Calcium; Female; Hyperthyroidism; Hypothyroidism; In Vitro Techniques; Iodine Isotopes; Kinetics; Magnesium; Male; Myocardium; Oxalates; Potassium Chloride; Rabbits; Sarcoplasmic Reticulum; Thyroid Diseases; Thyroxine

Topics: Adenosine Triphosphatases; Animals; Biological Transport; Calcium; Calcium Isotopes; Female; Hyperthyroidism; Hypothyroidism; Iodine; Iodine Isotopes; Male; Myocardium; Oxalates; Rabbits; Sarcoplasmic Reticulum; Thyroid Hormones; Thyroxine

Topics: Aspirin; Bilirubin; Blood Chemical Analysis; Blood Proteins; Cholesterol; Glucose; Heparin; Hyperthyroidism; Hypothyroidism; Iodides; Iodine; Iodine Isotopes; Mercury; Oxalates; Phenytoin; Potassium; Research; Thyroid Function Tests; Thyroid Hormones; Thyroxine; Triiodothyronine