Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Primary hyperparathyroidism (PHPT), the most common cause of hypercalcemia due to excessive secretion of PTH, is usually associated with hypophosphatemia and elevated serum chloride. Although PHPT was often complicated by renal stone disease and osteitis fibrosa in the past, routine screening of serum calcium (Ca) and development of sophisticated assay of parathyroid hormone have contributed to earlier detection of asymptomatic PHPT (APHPT). The proportion of APHPT patients, who have a mild elevation of serum Ca levels, usually within 1.0 mg/dL above the upper limit of normal, rose from 10-20% to approximately 45% of all PHPT patients in 1990-1995 in our clinic. Although it has been reported that the prevalence of PHPT is about 0.1% of the American population, the prevalence of PHPT appears to be far less in the Japanese population. Determination of a strategy for the increasing number of APHPT patients, is a pressing need but has yet to be accomplished. Treatment with bone antiresorptive drugs has met with some success, although the long-term efficacy of this treatment is not clear. The therapeutic effects of Ca-sensing receptor agonists appear promising.
 ...
PMID:Pathophysiology and diagnosis of primary hyperparathyroidism--strategy for asymptomatic primary hyperparathyroidism. 1091 83

Primary hyperparathyroidism is a rather frequent pathology characterised by hypersecretion of parathormone (PTH) which is caused by adenomas in 85% of all cases. At clinical onset, the most common symptoms are hypercalcemia-related (pain due to kidney stones, polyuria, gastrointestinal and neurological disorders) while rarer symptoms are due to brown tumors, expansive lesions often found in fibro-cystic osteitis. A case in which the patient showed recurrent mandibular brown tumors as initial clinical symptoms of primary hyperparathyroidism is described. This patient was examined for hypercalcemia, and a tumor mass at the left inferior mandibular branch was found. The patient had undergone surgical removal of a tumor in the left mandibular some years before, which was diagnosed as osteoclastoma. Primary hyperparathyroidism was diagnosed during recovery, and surgical removal of the parathyroid adenoma and mandibular tumor was performed. A histological diagnosis of large cell brown tumor was made. A microscopic observation of brown tumors which are made up of large multinuclear osteoclastic cells can often be confused with other large cell tumors during diagnosis. It is therefore necessary to exclude the presence of hyperparathyroidism with ionised calcium and, in cases of high values, intact PTH (iPTH), before performing a histological diagnosis of a large cell bone tumor. Throughout the course of primary hyperparathyroidism, brown tumors might appear in the absence of other specific symptoms and localize at the level of a single bone segment.
 ...
PMID:[Recurrent brown tumors as initial manifestation of primary hyperparathyroidism. An unusual presentation]. 1108 46

1. In the patient with renal insufficiency before dialysis, the phosphocalcic disorders appear insidiously. They are dominated by hyperparathyroidism which will be diagnosed on the initially yearly determination of plasma intact PTH as soon as creatinine clearance decreases below 60 ml/min, eventhough there is still no modification in plasma concentrations of calcium and phosphate. Its diagnosis should lead to initiate the therapeutic measures in order to prevent the irreversible thining of the corticals by endosteal resorption and later the occurrence of histological and radiological osteitis fibrosa favoring fractures. 2. Hyperparathyroidism prevention relies on two main measures: prevention of phosphate retention and hypocalcemia is implemented by progressive phosphate and protein restriction (from 1 g/kg/day when Ccr < 60 ml/min to 0.6 g/kg/day when Ccr < 20 ml/min) and administration of CaCO3 (1.5 g at lunch and dinner to better complex the phosphate) as soon as PTH is above normal; optimal vitamin D repeletion will be implemented by systematic supplementation of native vitamin D or 25OH vitamin D3 in order to bring P25OHD between 30-60 ng/ml (75-150 nmol/l) or more generally around the upper limit of the epidemiologic range of the laboratory; these measures should aim at maintaining plasma intact PTH in its optimal range variable with the degree of renal insufficiency: 0.5-1; 1-2.5 and 2-3 folds the upper limit of normal for creatinine clearance respectively at 60-30; 30-10 and < 10 ml/min. 3. Because of their hyperphosphatemic and hypercalcemic effect, 1 alpha-hydroxylated vitamin D derivatives will be regularly efficient and safe only when non-calcemic non-aluminic phosphate binder will be available and proven to be without side-effects. 4. Instrumental (surgical or by alcohol injection) parathyroidectomy should be considered when plasma intact PTH is > 5 to 7 times the upper limit of normal in the presence of hypercalcemia (> 2.60 mmol/l) and/or hyperphosphatemia (> 1.70 nmol/l) in spite of the above measures, the decision being reinforced by coexistence of bone radiologic abnormalities and metastatic calcifications. 5. Adynamic bone diseases are rare before hemodialysis in the absence of aluminum exposition by the drinking water or the aluminum-phosphate binders. In absence of aluminum it will be prevented by maintaining PTH in its optimal range. 6. Osteomalacia before hemodialysis is mainly due, in the absence of aluminum exposition, to vitamin D deficiency, hypocalcemia and acidosis. It is readily cured by physiological doses of native vitamin D or 25OH vitamin D3 bringing plasma 25 OHD above 16 ng/ml, in association with alkaline salts of calcium and if necessary of sodium bicarbonate.
 ...
PMID:[Renal osteodystrophy (2): its treatment in renal insufficiency before dialysis]. 1111 6

Calciphylaxis is a rapidly developing, fatal process of vascular calcium deposition with prominent cutaneous manifestation. We treated a long-term haemodialysis patient who developed an analogous disorder limited to the lungs. A 57-year-old man was admitted for initiation of peritoneal dialysis because limited cardiac reserve precluded further haemodialysis. He was treated successfully for pneumonia until hypoxia and progressive hypercalcaemia developed. (99m)Tc-methylene disphosphonate scintigraphy showed diffusely increased pulmonary uptake. Death supervened despite aggressive and successful treatment of hypercalcaemia. Autopsy studies included immunohistochemistry and morphometric studies of bone. Alveolar capillary walls showed diffuse calcium deposition. Both gross and microscopical findings differed from those of typical metastatic calcification in dialysis patients. Immunoreactivity for parathyroid hormone-related protein was present in the lesions. Bone histomorphometry indicated mild osteitis fibrosa. Pneumonia is believed to have caused local synthesis of parathyroid hormone-related protein that, along with high calcium x phosphorus product, contributed to calcium deposition. By analogy with the cutaneous process we termed the deposition "pulmonary calciphylaxis".
 ...
PMID:Acute respiratory failure due to "pulmonary calciphylaxis" in a maintenance haemodialysis patient. 1117 29

The prevalence and the clinical gravity of the various histopathological varieties of renal osteodystrophy in dialysis patients depends on the severity of both the aluminium intoxication and that of hyperparathyroidism. The prevalence of bone pains, fractures and hypercalcemias are the highest in adynamic bone diseases (ABD) with severe aluminium intoxication, then in osteitis fibrosa and mixed osteopathy, in the ABD with moderate aluminium intoxication and rare in the mild lesion in spite of similar moderate aluminium intoxication. In the absence of aluminium intoxication, hypercalcemia and hyperphosphatemia prevalence is higher only when intact PTH is more that 4 times the upper limit of normal. When PTH is between 1 and 2 folds the ULN this prevalence is null and bone mineral density is the highest. 2. The low turnover aluminic bone diseases (osteomalacic or adynamic) will be cured by long term deferoxamine treatment. The hazards of such treatment justify the performance of a bone biopsy to ensure the diagnosis. Their prevention relies on adequate treatment of tapwater and definitive exclusion of long term administration of aluminum phosphate binders. 3. Non aluminic osteomalacia will be treated according to the same guidelines given for the uremic patients before dialysis. 4. Non aluminic adynamic bone disease will be cured by means aiming at stimulating PTH secretion as discontinuing 1 alpha hydroxylated vitamin D derivatives, and, if there is no hyperphosphatemia by discontinuation of calcium supplement. In case of hyperphosphatemia in dialysis patients CaCO3 doses have to be nevertheless increased after the dialysate calcium concentration (DCa) has been decreased in order to induce a negative perdialytic calcium balance for PTH secretion stimulation. In the near future substitution of CaCO3 by non calcemic non aluminic phosphate binders will suffice. 5. Osteitis fibrosa due to hyperparathyroidism will be treated first by securing an optimal vitamin D repletion (bringing plasma 25OH vitamin D around 30 and 60 ng/ml or 75-150 nmol/l) and by correcting hypocalcemia and hyperphosphatemia by CaCO3 at high doses (3-12 g/day) taken with the meals. In case of hypercalcemia dialysate calcium concentration will be decreased to correct it or, in a near future, CaCO3 will be decreased to 3 g/day and hyperphosphatemia will be controlled by non calcemic, non aluminic phosphate binders. When hyperphosphatemia is controlled whereas plasma calcium is normal or low, 1 alpha hydroxylated vitamin D derivatives can be administered. 6. Instrumental parathyroidectomy should be considered when plasma levels of intact PTH remain above 7 folds the upper limit of normal whereas hyperphosphatemia persists and hypercalcemia occurs in order to prevent thining of the corticals and subsequent fracture risk. In case of previous exposition to aluminum, a deferoxamine test and/or a bone biopsy will be performed to decide a long term DFO treatment before the parathyroidectomy in order to prevent the transformation of a mixed osteopathy into an aluminic adynamic bone disease. 7. The difficulty of hyperparathyroidism control in dialysis patients is due to poor compliance to phosphate binders and to irreversible parathyroid hyperplasia with occured before the dialysis stage. This stress the primary importance if its early prevention without iatrogenia by first CaCO3 and vitamin D repletion, as soon as the creatinine clearance decreases below 60 ml/min/1.73 m2.
 ...
PMID:[Renal osteodystrophy (3); its treatment in dialysis patients]. 1121 85

Osteitis fibrosa cystica (brown tumors) can be a skeletal manifestation of advanced hyperparathyroidism, including parathyroid cancer. Severe osteitis fibrosa cystica can mimic metastatic bone diseases especially in patients with a history of cancer. Because the treatment and prognosis of these two problems differ greatly considering hyperparathyroidism in the differential diagnosis of patients found to have osteolytic lesions is critical for the appropriate management of these patients. In this case report we describe a patient with a history of renal cell cancer and presumed osteolytic bone metastases. During prophylactic intramedullary rodding to prevent pathologic fracture of her femur she was found to have a benign lesion related to her previously undiagnosed hyperparathyroidism caused by an underlying parathyroid cancer. A detailed review of this disease and the associated bone changes is also included to underscore the importance of an adequate differential diagnosis as well as optimal management. Patients with hypercalcemia or bony lesions should not automatically be treated palliatively for metastatic disease just because of a past medical history of cancer. Hyperparathyroidism is a readily curable problem if properly diagnosed.
 ...
PMID:Disseminated brown tumors from hyperparathyroidism masquerading as metastatic cancer: a complication of parathyroid carcinoma. 1160 52

The typical manifestations of severe hypercalcemia with osteitis fibrosa cystica have become exceedingly rare. We describe the case of a woman hospitalized for a tibial tumor with functional impotence, leading to a diagnosis of primary hyperparathyroidism (HPT I) associated with profound vitamin D deficiency. This 31-year-old woman was admitted, after two pregnancies complicated by the HELLP syndrome. Preoperative laboratory values were as follows: calcemia 4.05 mmol/l (2.2-2.6); urinary calcium 30 mmol/24 h (1.25-7.5); parathormone (PTH) 1 195 pg/ml (10-60); and 25 OH-vitamin D 13 nmol/l (22-120). Specific MIBI uptake by the tibial lesion oriented the diagnosis towards a brown tumor. After surgical excision of a parathyroid adenoma and the brown tumor (associated with tibial fracture), calcemia fell to 1.55 mmol/l and normalized after three months. Urinary calcium fell to 0.1 mmol/24 h and remained low during the 2 years following surgery. Vitamin D levels rapidly normalized on supplementation (87 nmol/l). PTH levels fell markedly after surgery but remained higher than normal till 2 years after surgery despite normalization of calcemia three months after. Bone repair, estimated by means of bone densitometry, improved from preoperative Z-score values of - 6.54, - 5.20 and - 3.50 in the left femoral neck, right femoral neck and lumbar spine, respectively, to - 0.20, - 1.55 and - 0.28, respectively, one year after surgery. In conclusion, this case illustrates: 1) the severe osseous expression of HPT probably related to vitamin D deficiency; 2) specific MIBI uptake by the bone lesion, orientating the diagnosis towards a brown tumor; 3) the consequences of vitamin D deficiency on postoperative outcome, with transient severe initial hypocalcemia related to bone calcium avidity; 4) a possible link between HPT and the HELLP syndrome.
 ...
PMID:Vitamin D deficiency and severe hyperparathyroidism. 1252 57

Phosphorus control remains a relevant clinical problem in dialysis patients. With age, however, serum phosphorus level decreases significantly because of a spontaneous decrease in protein intake. Older patients usually need lower doses of phosphorus binders. Nevertheless, hyperphosphataemia is observed in a quarter of patients aged >65 years. Phosphorus retention is related to an imbalance between phosphorus intake and removal by dialysis, and is usually aggravated when vitamin D analogues are employed. Hyperphosphataemia induces secondary hyperparathyroidism and the development of osteitis fibrosa. Recent publications describe an association between phosphorus retention and increased calcium and phosphorus product (Ca2+ x P), with significant progression of tissue calcification and higher mortality risk. Dietary intervention, phosphorus removal during dialysis and phosphorus binders are current methods for the management of hyperphosphataemia. However, the phosphorus removed by standard haemodialysis is insufficient to achieve a neutral phosphorus balance when protein intake is >50 g/day. Additional protein restriction may impose the risk of a negative protein balance. More frequent dialysis may help to control resistant hyperphosphataemia. Phosphorus binders constitute the mainstay of serum phosphorus level control in end-stage renal disease patients. Aluminium-based phosphorus binders, associated with toxic effects, have largely been substituted by calcium-based phosphorus binders. However, widespread use of calcium-based phosphorus binders has evidenced the frequent appearance of hypercalcaemia and long-term progressive cardiovascular calcification. Sevelamer, a relatively new phosphorus binder, has proved efficacious in lowering serum phosphorus and parathyroid hormone (PTH) levels without inducing hypercalcaemia. Furthermore, several investigators have reported that sevelamer may prevent progression of coronary calcification. However, its efficacy in severe cases of hyperphosphataemia remains to be confirmed in large series. There are no specific guidelines for phosphorus control in the elderly. Until more information is available, levels of mineral metabolites should be targeted in the same range as those recommended for the general population on dialysis (calcium 8.7-10.2 mg/dL, phosphorus 3.5-5.5 mg/dL and Ca2+ x P 50-55 mg2/dL2). PTH values over 120 ng/L help to avoid adynamic bone disease. Since elderly patients have a higher incidence of adynamic bone (which buffers less calcium) and vascular calcification, sevelamer should be the phosphorus binder of choice in this population; but sevelamer is costly and its long-term efficacy has not been definitively validated. Patients with low normal levels of calcium may receive calcium-based phosphorus binders with little risk. Patients with low values of PTH and high normal calcium should receive sevelamer. Tailored combinations of calcium-based phosphorus binders and sevelamer should be considered, and calcium dialysate concentration adjusted accordingly.
 ...
PMID:Management of hyperphosphataemia in dialysis patients: role of phosphate binders in the elderly. 1497 34

Hyperparathyroidism is a disease characterized by hypercalcemia with hypophosphoremia resulting from increased secretion of parathyroid hormone (PTH). The disease may be divided into 3 forms: a) primary, b) secondary, c) tertiary (secondary refractory form). Primary hyperparathyroidism is rare in children; hyperplasia is more frequent during the early years of life (neonates and infants) and is difficult to distinguish from adenoma in children. The disease may be asymptomatic; elevated calcemia levels (>12 <13.5 mg/dl) are accompanied by anorexia, asthenia and persistent stipsis; severely elevated concentrations (>13.5 mg/dl) are accompanied by nausea, vomiting, polyuria due to osmosis, with dehydration and progressive onset of lethargy, stupor and coma. Osteopenia or osteitis fibrosa cystica may be present due to augmented bone resorption. Height and weight increases are altered due to anorexia and dehydration. Differential diagnosis includes iatrogenic causes of hypercalcemia (excessive vitamin D intake, prolonged immobilization, etc.) and idiopathic familial hypercalcemia. Emergency treatment is required in cases of extremely elevated hypercalcemia (Ca >13.5-14 mg/dl), due to risk of injury to the heart, the central nervous system, the gastrointestinal tract and the kidneys. The 4 cardinal points of treatment are: hydration, calciuresis, inhibition of bone calcium resorption, treatment of the cause underlying hyperparathyroidism. Secondary hyperparathyroidism is found in cases where chronic hypocalcemia is present, particularly in chronic renal failure, untreated deficiency rickets, chronic intestinal malabsorption, hepatobiliary disease, types I and II vitamin D-dependent rickets, tubular acidosis or Fanconi's syndrome. The tertiary form is distinguished by the autonomous nature of the parathyroid glands which have become hypertrophic/hyperplastic due to uncontrollable, chronic severe renal failure. It can also be of iatrogenic origin due to excessive intake of inorganic phosphates in familial hypophosphatemic rickets or chronic vitamin D deficiency.
 ...
PMID:Hyperparathyroidism. 1524 24

Pharmacologic interventions designed to control hyperparathyroidism (HPT) in uremic patients have limitations and potentially serious adverse clinical consequences. Hence, one still has to resort to surgical parathyroidectomy (PTX) in a considerable number of dialysis patients. The aim of the present study was to illustrate our experience with 26 renal dialysis patients who underwent surgical PTX. The main indications for PTX included iPTH > 1000 pg/mL associated with severe osteitis fibrosa, debilitating pruritus, marked soft tissue calcification, or hypercalcemia with hyperphosphatemia, which sometimes complicated vitamin D therapy. All patients were resistant to more conservative measures, including control of serum phosphate, attention to oral intake and dialysate calcium levels, and oral/intravenous administration of active vitamin-D-pulse therapy. Ultrasound and technetium 99-sestamibi scan were used to image the thyroid and the parathyroid glands. Total PTX with autotransplantation was performed in 23 patients; subtotal PTX was performed in 3 patients. Histology of frozen sections taken intraoperatively showed nodular changes in 14 and diffuse hyperplasia in 12 cases. During the 2-year follow-up period significant reductions in parathyroid hormone, alkaline phospatase blood levels, skeletal changes, and soft tissue calcifications were observed. Pruritus improved in half the cases. Some improvement in hemoglobin and hematocrit was also noticed. The complication rate after PTX was low. Transient postoperative hypocalcemia requiring intensification of calcium and vitamin D therapy was seen in cases with high preoperative alkaline phosphatase levels. Recurrence was observed in two cases. Hypoparathyroidism was not recorded. We conclude that surgical reduction of parathyroid mass is a safe and effective treatment for symptomatic disease not suppressible by pharmacologic means.
 ...
PMID:Effectiveness of surgical parathyroidectomy for secondary hyperparathyroidism in renal dialysis patients in Qatar. 1535 Apr 84


<< Previous 1 2 3 4 5 6 7 8 9 Next >>