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J M Monchik

Publications and source records attributed to J M Monchik.

31 records · Page 2Linked to original sources
PubMed1984

The role of ionized calcium in the diagnosis of subtle hypercalcemia in symptomatic primary hyperparathyroidism.

This report details our continued study of the role of ionized calcium (CAI) in the diagnosis of symptomatic primary hyperparathyroidism (HPT) in patients with persistently normal total serum calcium (CAT) or fluctuating normal total serum calcium levels with elevated CAT. A patient was considered to have fluctuating CAT values if at least 40% of the CAT values were within the normal range. Our previous study demonstrated that CAI provided no additional diagnostic benefit in patients with HPT who had persistently elevated CAT levels. This retrospective study adds 15 additional patients to the four previously reported patients whose workup for HPT included normal or fluctuating normal total serum calcium with elevated CAT values. Eighteen of these 19 patients had complications or symptoms referable to HPT. Nine of these patients had renal calculi. CAT was measured by atomic absorption spectroscopy and CAI was measured by a calcium-selective ion flow-through electrode. One hundred fifty-one concurrent preoperative measurements of CAT and CAI from these 19 patients were used for analysis. Overall, 46 (30.5%) of the CAT values were elevated, whereas 134 (88.7%) of the concurrent CAI values were elevated (P less than 0.001). In three of these 19 patients all preoperative CAT values were within normal limits, however, 20 of the 21 (95%) concurrent CAI values were elevated. In the remaining 16 patients the CAT values fluctuated between normal and elevated. In all of these patients, at least 40% of the preoperative CAT values were normal, and in 15 of these 16 patients at least 50% of the preoperative CAT values were within the normal range. In this fluctuating category there were 130 concurrent values of CAT and CAI. Only 46 of these 130 (35.4%) CAT values were elevated, whereas 114 of the 130 (87.7%) CAI values were elevated (P less than 0.001). All patients underwent parathyroid operation; 15 patients had a parathyroid adenoma and four had hyperplasia. The CAI and CAT values returned to normal in all patients subsequent to operation. These data indicate that the measurement of serum ionized calcium appears to play an important role in the identification of symptomatic HPT in patients who have normal or fluctuating normal total serum calcium with elevated CAT values.

Adenoma↗
PubMed1983

Parathyroid surgery: the role of chief cell intracellular fat staining with osmium carmine in the intraoperative management of patients with primary hyperparathyroidism.

The surgeon's gross evaluation, the hematoxylin and eosin stain, which assesses extracellular fat, and a new intracellular fat stain, osmium carmine, were comparatively evaluated in 30 consecutive patients who underwent surgery for primary hyperparathyroidism. The surgeon's gross judgment of enlarged and normal parathyroid tissue resulted in the correct functional assessment in 98% and 97% of the glands, respectively. The surgeon's functional assessment was correct in seven of 10 parathyroid glands that were considered by gross examination to be slightly enlarged (50 to 80 mg). The osmium carmine intracellular fat stain provided a correct functional assessment in all 10 of these glands. The osmium carmine stain also appears to have a role in providing scientific quantitative data to limit operations in patients who have a parathyroid adenoma to removal of the adenoma and biopsy of a grossly normal gland that demonstrates normal intracellular fat. Only one side of the neck was explored in 11 patients who fulfilled these criteria. There has been no persistent or recurrent hypercalcemia in these patients.

Adenoma↗
PubMed1980

Role of selective venous catheterization of the small thyroid veins as a diagnostic study in hypercalcemic states.

Previous studies of selective venous catheterization stress its value in localizing hyperfunctioning parathyroid tissue in patients with an established diagnosis of hyperparathyroidism. Our study presents our experience with selective venous catheterization as a diagnostic aid in differential diagnosis of hypercalcemia. In our four patients, an extensive metabolic work-up did not resolve the differential diagnosis of hypercalcemia, and selective venous catheterization provided the ultimate data that led to the correct diagnosis of hypercalcemia in each patient. Selective venous catheterization can be an important diagnostic study in carefully selected patients with hypercalcemia.

Adenoma↗
PubMed1977

Nonautonomy of parathyroid hormone and urinary cyclic AMP in primary hyperparathyroidism.

This study demonstrates that appreciable changes in serum parathyroid hormone and urinary cyclic AMP occur during experimentally induced hyper- and hypocalcemia in almost all patients with primary hyperparathyroidism regardless of histology. A single patient with tertiary hyperparathyroidism also demonstrated a significant elevation of serum parathyroid hormone and urinary cyclic AMP in response to EDTA induced reduction in ionized calcium. Thus, total autonomy of hormone secretion was not present in the great majority of the patients with a parathyroid adenoma, parathyroid hyperplasia, or the single patient with tertiary hyperparathyroidism. Therefore, preoperative evaluation of the rsponse of urinary cyclic AMP and serum parapthyroid hormone to EDTA or calcium infusion will not distinguish parathyroid adenomas from hyperplasia on the basis of total autonomy of hormone secretion. If a difference in secretory control is present between parathyroid adenomas and parathyroid hyperplasia, it is more subtle than total autonomy for adenomas and nonautonomy for hyperplasia.

Adenoma↗
PubMed1976

Experimental induction of hypoparathyroidism with parathyroid hormone antibodies.

This study describes the effect of a single injection of parathyroid hormone antiserum on the serum calcium, serum phosphate, urinary cyclic AMP, and urinary phosphate levels in the intact perfused rat. A significant decline in serum calcium level with concomitant elevation in serum phosphate level and decreased urinary excretion of phosphate and cyclic AMP was noted. These findings strongly suggest that a transient hypoparathyroid state was induced by the parathyroid hormone antiserum.

Animals↗
PubMed1976

Ionized and total serum calcium and parathyroid hormone in hyperthyroidism.

Total and ionized calcium concentrations as well as parathyroid hormone levels were measured in a group of hyperthyroid persons. Ionized and total calcium levels were elevated in 21 of 45 (47%) and in 12 of 45 (27%) thyrotoxic patients, respectively. Mean ionized and total calcium levels were higher in these 45 patients than in normal persons. Using two different radioimmunoassay systems for a total of 44 determinations, mean parathyroid hormone levels were lower in thyrotoxic patients than in subjects with proved hyperparathyroidism. These data suggest that [1] elevations of both ionized and total calcium concentrations occur frequently in thyrotoxic patients; [2] ionized calcium concentrations may be elevated in a higher percentage of hyperthyroid subjects than are total calcium concentrations; and [3] the hypercalcemia associated with thyrotoxicosis is not associated with elevated parathyroid hormone levels.

Calcium↗
PubMed1975

Localization of hyperfunctioning parathyroid tissue. Radioimmunoassay of parathyroid hormone on samples from the large veins of the neck and thorax and selectively catheterized thyroid veins.

Radioimmunoassay of parathyroid hormone on samples obtained from the large veins of the neck and thorax was utilized for localization in twenty-one patients with hyperparathyroidism. In seventeen of these patients, as many of the thyroid and mediastinal veins as possible were also sampled. This study reveals that sampling of the large veins of the neck and thorax is an insensitive means of adenoma from hyperplasia. Anatomic variations in the drainage of the inferior thyroid veins and dilution of the parathyroid venous effluent by the large veins of the neck and thorax seem to explain this insensitivity and the occasionally misleading results of large vein sampling. Sampling of the small thyroid veins, however, is a sensitive and specific means of localization and permitted preoperative differentiation of adenoma from hyperplasia in fourteen of our seventeen patients. Communications between the inferior thyroid and thymic veins and the fact that mediastinal adenomas frequently bring their blood supply down from the cerevical area suggest that sampling of the small thyroid veins may be of only limited value in identifying a mediastinal adenoma.

Adenoma↗
PubMed1975

The localization of abnormal mediastinal parathyroid glands.

The venous drainage of parathyroid glands ectopically located in the mediastinum is generally caraniad into the inferior thyroid veins. Parathyroid glands in the neck can cause elevated concentrations of parathyroid hormone in mediastinal veins because of thyroidalthymic anastomoses. Therefore venous sampling alone cannot distinguish cervical from mediastinal adenomas. Arteriography can localize mediastinal parathyroids and should be perfomred before any repeat exploration.

Adenoma↗