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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined the predictive value of urea kinetics for patient outcomes in CAPD by measuring dialysis index (DI; a means of quantifying CAPD dose using urea kinetics), KT/V and normalized protein catabolic rate (PCRN) on 222 occasions in 76 new patients at the time of starting CAPD and at subsequent six month intervals. We investigated how these indices altered with time and in relation to each other, and how they correlated with a wide range of subsequent patient outcomes. DI, KT/V and PCRN all tended to decrease with time on CAPD (P less than 0.0004, less than 0.0001 and 0.0005, respectively). DI and KT/V were highly correlated with each other (r = 0.89, P less than 0.0001) and both correlated with PCRN (r = 0.57, P less than 0.0001 and r = 0.60, P less than 0.0001, respectively). DI and KT/V both correlated inversely with subsequent values for serum creatinine (P less than 0.0001), urea (P less than 0.0002), potassium (P less than 0.02) and phosphate (P less than 0.002), and directly with bicarbonate (P less than 0.0001). PCRN correlated inversely with serum creatinine (P less than 0.0002) and directly with urea (P less than 0.0001) and with the number of blood transfusions received (P less than 0.03). None of these indices correlated with levels of hemoglobin, PTH, alkaline phosphatase or albumin, or with nerve conduction velocity or any other subsequent clinical outcomes including death, technique failure, hospital days, peritonitis rate and subjective indices of fatigue, pruritus and insomnia. We conclude that the urea kinetic model is predictive of some biochemical outcomes but not of clinical outcomes in CAPD patients.
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PMID:Lack of correlation between urea kinetic indices and clinical outcomes in CAPD patients. 205 26

We present the case of a woman with classical osteitis fibrosa cystica generalisata von Recklinghausen, caused by a single adenoma of the left inferior parathyroid gland. After six months with increasing bone pain, pathological fractures and cystic lesions radiologically, hyperparathyroidism was diagnosed by persistent elevated levels of serum calcium, and elevated levels of PTH. Surgical extirpation of the parathyroid adenoma caused a period with severe hypocalcemia followed by complete clinical restitution. The diagnosis should be considered in any case of persistent bone pain and uncharacteristic fatigue.
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PMID:[Osteitis fibrosa cystica von Recklinghausen]. 232 Dec 26

The atrophy produced by endocrine disorders is primarily due to alterations in protein and carbohydrate metabolism. Type II muscle fibers are more severely affected than are Type I fibers. Steroid myopathy and the myopathy associated with excess ACTH have a typical pattern of proximal weakness affecting the legs more than the arms. Steroid myopathy is usually not apparent until other signs of glucocorticoid excess are present. Treatments of steroid myopathy are as follows: Lower the dose of steroid, use a nonfluorinated glucocorticoid, and exercise or physical therapy. Adrenal insufficiency produces generalized weakness, muscle cramping, and fatigue in 50 per cent of patients. Some patients also develop hyperkalemic paralysis. The treatment is hormone replacement. Thyrotoxicosis produces myopathy caused by net protein catabolism, accelerated basal metabolic rate and impaired carbohydrate metabolism. Shortening of contraction time may result from accelerated myosin ATPase activity and enhanced calcium uptake by the sarcoplasmic reticulum. Depolarization of the muscle fiber and impaired Na-K activity in muscle may predispose to thyrotoxic periodic paralysis. Neuromuscular presynaptic impairment may account for the worsening of myasthenia gravis by thyrotoxicosis. In hypothyroidism, impaired energy metabolism may limit force generation. Slow contraction and relaxation reflect reduction in myosin ATPase activity and impaired calcium uptake by the sarcoplasmic reticulum. Treatment for thyroid-associated muscle disorders is restoration of a euthyroid state. Muscle weakness associated with hypopituitarism is due to loss of thyroid and adrenal cortical hormones. Children require growth hormone for muscle development. T3 and growth hormone synergize to maintain normal protein synthesis. Primary and secondary hyperparathyroidism and osteomalacia are often associated with proximal weakness and fatigability. The myopathy improves with restoration of normal PTH levels and vitamin D replacement. Hypoparathyroidism and pseudohypothyroidism are associated with tetany. Tetany is worsened by alkalosis and is treated by calcium and magnesium replacement.
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PMID:Endocrine myopathies. 306 2

It could be advantageous for the parathyroids to be able to sense not only the absolute concentration of extracellular Ca2+, but also the rate and direction of change of Ca2+, thereby allowing the parathyroids to respond earlier to threats to Ca2+ homeostasis. By using high and low Ca2+ dialysis in a single session, we examined the parathyroid response to direction of change of Ca2+ during acute Ca2+ perturbation in nine hemodialysis patients. Separate PTH/ionized calcium (PTH/iCa) response curves were generated for rising Ca2+ and falling Ca2+. Significant directional hysteresis (higher PTH level during falling than during rising Ca2+) was found. During hypercalcemia, PTH levels were between 2.2 and 1.6 times higher at iCa concentrations of between 0 and +0.1 mM above the baseline iCa, when Ca2+ was falling than when it was rising. During the phase of induced hypocalcemia, parathyroid fatigue was seen in six of the nine patients. Fatigue patients tended to have higher basal PTH (1-84) levels than those not showing fatigue. The existence of fatigue provides an explanation for directional hysteresis during hypocalcemia, and therefore parathyroid sensing of the direction of change of Ca2+ could not be assessed during hypocalcemia. These studies demonstrate a capacity of the parathyroids to sense the direction of movement of Ca2+ during hypercalcemia.
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PMID:Parathyroid sensing of the direction of change of calcium in uremia. 851 Mar 89

Many studies document bone loss at diagnosis in patients with PHPT (including mild PHPT) that is greater than would be expected in comparable persons without this condition. However, there is no general agreement regarding the severity of bone mass loss in these patients and the rate at which it progresses. A few studies suggest that such accelerated osteoporosis may be self-limited, with patients showing no further decline in BMD after diagnosis. There is insufficient evidence to conclude that PTH-related bone loss is associated with an increased risk of fracture. The few studies that have evaluated the risk of fracture in these patients are conflicting. Some evidence also suggest that, like bone loss in these patients, fracture risk may change during the course of the disease. One study found that patients with PHPT (including those with mild hypercalcemia) were more likely than matched controls to have a history of fractures prior to diagnosis, but that both groups had similar rates of fractures during followup. Moreover, the studies of fractures suffer from several limitations, such as nonrandomization of patients, different definitions of vertebral fractures, small study populations, and short followup times. There is also insufficient evidence to determine the effect of parathyroidectomy on the incidence of fractures in patients with mild PHPT, partly because the natural history of this condition is incompletely understood. Although studies demonstrate that patients with PHPT gain bone mass following parathyroidectomy, the bone reparation is incomplete and bone mass density remains below normal, even though the hyperparathyroidism is cured. Currently, decisions to perform parathyroidectomy are based on signs and symptoms of bone disease, metabolically active renal stones, decreased renal function, fatigue and/or depression, and high levels of serum calcium. Although the use of bone mass measurements has been advocated to aid clinical decisions regarding the risks and benefits of surgery, specific bone changes that indicate the need for parathyroidectomy have not been clearly established. There are virtually no prospective data that evaluate decisions to operate based upon bone mass measurements nor randomized clinical trials comparing the outcome of surgically treated patients with those who have not had surgery. Based on the literature, bone mass measurements cannot predict who among asymptomatic patients will require parathyroidectomy. There is some evidence that nonsurgically treated patients and those who remained hypercalcemic after unsuccessful surgery lost bone at the same percentage rate as normal control subjects.
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PMID:Bone densitometry: patients with asymptomatic primary hyperparathyroidism part I. Technical report. 893 32

A 51-year-old woman was admitted because of general fatigue assumed to be due to climacteric disturbance. Laboratory examinations suggested a diagnosis of hyperparathyroidism based on high serum levels of Ca, intact PTH, and high-sensitivity PTH. No abnormalities were found in the cervix. Chest X-ray films and CT scans showed a mass measuring 4 cm in the right postero-upper mediastinum. The tumor was positive on a parathyroid scintigram, and was diagnosed as a mediastinal parathyroid adenoma with hyperparathyroidism. Operative findings showed a tumor surrounded by the superior vena cava, vagus nerve, azygos vein, and brachiocephalic artery. Careful resection of the hypervascular tumor from surrounding tissues was performed using a thoracoscopic technique alone. The postoperative course was uneventful. Serum values of Ca, intact PTH, and high-sensitivity PTH decreased to within normal ranges. after surgery. Pathohistological study confirmed the diagnosis of parathyroid adenoma including a cyst caused by degeneration of the tumor.
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PMID:[Thoracoscopic resection of mediastinal parathyroid adenoma with cyst and hyperparathyroidism--a case report]. 945 9

Primary hyperparathyroidism is the most common cause of hypercalcemia and 80-85% of the patients have parathyroid tumors. The purpose of this retrospective review was to analyse whether differences exist between patients with parathyroid tumors treated in the 1980s and 1990s. Between 1980-1997, 253 patients underwent initial surgical neck exploration for hyperfunctioning parathyroid tumors. Renal (polyuria, nocturia, renal colic due to lithiasis), rheumatologic (bone and joint pain), neurological (fatigue, memory loss, depression) and gastrointestinal (dyspepsia, anorexia, nausea) symptoms were recorded and main biochemical parameters were measured. In all patients one or more preoperative localization procedures were carried out prior to successful parathyroidectomy, and the confirmation of imaging findings was obtained after surgery. The patients were divided in two groups. Group A: 121 (47.8%) patients who underwent surgery from 1980-1989; Group B: 132 (52.2%) patients in whom parathyroidectomy was performed from 1990-1997. There were no differences (p=NS) between the two groups in average age, preoperative serum creatinine and intact-PTH levels. Symptoms were most common in Group A, and pre-operative serum calcium levels were significantly lower in Group B. Ultrasonography (n=191) sensitivity did not improve significantly (82.8% vs 82.9%), but positive predictive value (PPV) was higher (89.8% vs 96.0%). CT-scan (n=73) sensitivity was 79.2% and 82.6%, and PPV was 95.0% and 100% in Groups A and B, respectively. 201Tl/99mTc subtraction scintigraphy (n=111, Group A) was 84.6% sensitive (PPV=92.6%) whereas 99mTc-sestamibi scanning (n=90, Group B) was 85.1% sensitive (PPV=96.1%). In conclusion, the clinical features of parathyroid tumors has changed in the nineties and increasing asymptomatic pHPT rate has been found. Although sensitivity and PPV of preoperative localization procedures has improved moderately, at present noninvasive techniques may offer excellent results and should be used in all patients with suspected parathyroid tumors.
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PMID:Tumors of the parathyroid glands. Changes in clinical features and in noninvasive localization studies sensitivity. 1084 Sep 29

A clear relationship between vitamin D status and the clinical indices of primary hyperparathyroidism (pHPT) severity has not been convincingly established. We proposed that such a relationship might exist, in so far as vitamin D deficiency could contribute to the severity of metabolic bone disease and promote the growth of the parathyroid tumor. Accordingly, we undertook a retrospective study and analyzed the clinical, biochemical, radiological and histopathological findings in a group of 49 patients who underwent parathyroidectomy at our center. Patients who had skeletal X-rays were grouped, according to their X-ray findings, in group A (19 patients; 45%) if they had severe bone changes, or group B (23 patients; 55%) if they had mild or no bone changes. Patients were also stratified according to their 25-hydroxyvitamin D (25-OHD) levels in tertiles. The 2 groups were compared using Fisher's exact test or analysis of variance as appropriate. Group A patients were younger (p=0.001), had more musculoskeletal symptoms (p=0.0003), and complained more frequently of fatigue (p=0.02). They had higher alkaline phosphatase (AP; p=0.0002), PTH index (p=0.0007), and serum Ca level (p=0.006). There were more patients from the lower and middle vitamin D tertiles and fewer patients from the upper vitamin D tertile in group A (p=0.02). Post-operative severe hypo-calcemia was more prevalent in group A patients (p<0.0001). Resected parathyroid tumors were larger in size in group A patients (p=0.01), and weighed more (p=0.01). There was a positive correlation between the weight of the parathyroid tumor and the PTH index (p=0.002), and AP level (p=0.0007). We concluded that vitamin D deficiency is a contributing factor to both the severity of bone disease and the high activity of parathyroid tumors seen in many patients with pHPT in vitamin D deficient regions.
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PMID:The effect of vitamin D status on the severity of bone disease and on the other features of primary hyperparathyroidism (pHPT) in a vitamin D deficient region. 1564 43

To investigate rates of bone turnover and calcium homeostasis in Gambian women, we recruited 103 peri- and postmenopausal women, aged 45 to 80+ years and 11 women of reproductive age. Fasting blood was analyzed for plasma osteocalcin, PTH, 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D], total- and bone-specific alkaline phosphatase. Plasma and urinary calcium, inorganic phosphate, sodium, potassium, creatinine, and albumin and urine free deoxypyridinoline (Dpd) was also measured. Samples from 20 premenopausal and 31 postmenopausal women from Cambridge, UK were analyzed, using the same methodology for comparison. For the Gambian women, peak calcium excretion occurred at around 50 years of age. For women aged > or =45 years, calcium excretion decreased by 3.0% per year of age (SE 1%; P < 0.005). In this age group, 25(OH)D also decreased with age (P < 0.005). Urinary sodium output, pH, and titratable acid output decreased (all P < 0.05) and total alkaline phosphatase (P < 0.005), osteocalcin (P < 0.005), and PTH (P < 0.05) increased with age. Comparisons were made between the following groups of Gambian and British women: premenopausal, early (age 55-64 years)- and late (age 65+ years)-postmenopausal. Gambian women of all ages were lighter (P < 0.001), shorter (P < 0.01), and had higher plasma bone-specific alkaline phosphatase activity (P < 0.05) and higher concentrations of osteocalcin (P < 0.05), PTH (P < 0.001), 1,25(OH)(2)D (P < 0.001), and 25(OH)D (P < 0.001). There were no consistent differences in calcitonin, while urinary free Dpd outputs were lower in the Gambians (P < 0.001). Plasma calcium, phosphate, and albumin (P < 0.01) were significantly lower. Urinary calcium, phosphate, sodium, and potassium excretion were lower, particularly in the postmenopausal group (P < 0.001). Although Gambian urine pH was more acidic, titratable acid output was lower (P < 0.01). These data show that Gambian women with low dietary calcium intakes and good vitamin D status have low urinary calcium excretion and that menopausal changes in calcium and bone metabolism among Gambian women are similar to those seen in other populations. In addition, they demonstrate that Gambian women of all ages have raised plasma PTH and 1,25(OH)(2)D concentrations and raised markers of osteoblast activity. We postulate that high endogenous PTH concentrations may be beneficial to bone health in Gambian women, removing fatigue damage and improving bone quality.
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PMID:Parathyroid hormone and rates of bone formation are raised in perimenopausal rural Gambian women. 1578 Sep 75

Primary hyperparathyroidism (PHPT) is characterized by excessive PTH secretion in respect to calcium homeostasis needs, due to parathyroid adenoma (80% of cases), hyperplasia (15-20%), or carcinoma (1-2%). In familial forms of PHPT, several mutations have an established role: menin gene for MEN type 1, RET for MEN type 2a, calcium-sensing receptor gene for familial hypocalciuric hypercalcemia, parafibromin gene for PHPT-jaw tumour and carcinoma. Etiology of sporadic adenomas (80% of PHPT cases) is less defined, being most commonly found a mutation of menin gene or activation of PRAD1 oncogene. In recent years, the classical features of the disease became less common. Typically, bone involvement is now represented by a reduced bone mass at skeletal sites more rich in cortical tissue. Prominently trabecular skeletal sites are relatively spared, because of the anabolic effects of a slight PTH excess on trabecular tissue. PHPT patients may have increased fracture risk, though it is not clear why bone damage is more severe in a subgroup of patients. Clinical features of hypercalcemia may be fatigue, anorexia, thirst, and polyuria. Vague neurological and psychiatric symptoms, such as weakness, anxiety, depression, paresthesias, and muscular cramps may ameliorate after parathyroidectomy. Recent reports indicate increased cardiovascular mortality in PHPT patients. Diagnosis is based on the detection of hypercalcemia, together with inappropriately high serum PTH levels. Preoperative localization of the diseased glands is mandatory in persistent or recurrent PHPT, as like as when minimally invasive surgery is planned. High resolution ultrasonography and SPECT double-phase 99m Tc-sestamibi scintigraphy are the most commonly employed techniques. Intraoperatory PTH assay may confirm successful surgery when serum concentrations decrease more than 50%. Surgical therapy is indicated in patients with renal or skeletal complications, such as in those with previous parathyrotoxic crisis. Many surgeons in recent years adopted minimally invasive parathyroidectomy. Medical treatment is an option for patients unwilling or unfitted for surgery because of severe concomitant diseases. Employed therapy includes estrogens, SERMs, bisphosphonates and calcimimetics.
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PMID:[Primary hyperparathyroidism]. 1638 70


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