D-penicillamine-induced myasthenia gravis in a case of eosinophilic fasciitis

During the period 1983-1995, 200 chronic renal failure patients (115 males and 85 females) were parathyroidectomized for hyperparathyroidism in our Department. In all of them, the presenting clinical symptoms, physical signs, biochemical and radiological tests were typically those of hyperparathyroidism. One hundred ninety patients were operated for the first time whereas 10 were re-operated due to relapse of the disease; 3 of these cases were primary hyperparathyroidism, 182 secondary and 5 tertiary. All three primary hyperparathyroidism cases underwent removal of the adenoma; in the group of secondary hyperparathyroidism, 50 underwent removal of all the parathyroid glands found, 25 underwent total parathyroidectomy with forearm or deltoid autograft and 60 subtotal parathyroidectomy whereas in 39 and 8 patients only 3 and 2 parathyroid glands were found respectively. In the group of tertiary hyperparathyroidism, we removed only the hyperplastic gland detected as the operative detection of the rest was not possible. Ten cases were re-operated for removal of the remaining glands. No complications were noted postoperatively, apart from severe hypocalcemia in 20 cases, treated successfully by Calcium and Vitamin D administration. The highest relapse rate was noted among the 8 patients with only the 2 parathyroid glands removed. It seems that total or subtotal parathyroidectomy represents the most successful methods for surgical treatment of hyperparathyroidism complicating chronic renal failure.     

Analysis of proliferative activity of the parathyroid glands using proliferating cell nuclear antigen in patients with hyperparathyroidism

To elucidate the cellular proliferative kinetics of the parathyroidal gland in patients with hyperparathyroidism, we investigated the expression of proliferating cell nuclear antigen (PCNA) in parathyroidal tissues using an immunohistochemical procedure. The PCNA labeling index (LI; maximum LI, maximal stained area; average LI, evenly distributed stained area) indicating cellular proliferative activity was defined as the number of PCNA-positive cells per 1000 parathyroid cells in the region of interest. We used these indexes to compare and investigate the proliferative activity of parathyroid cells under various conditions. The specimens used for the study were 42 parathyroid glands from 21 patients with primary hyperparathyroidism (19 cases of adenoma and 2 cases of primary hyperplasia due to multiple endocrine neoplasia type 1) and 129 parathyroid glands from 32 patients with secondary hyperparathyroidism. An additional 40 parathyroid glands resected during thyroid surgery of 30 normocalcemic patients were used as normal controls. In normally functioning parathyroids, a small number of cells in the growth phase were found. In primary hyperparathyroidism, proliferative activity was highest in the adenoma followed by primary hyperplasia. In contrast, the PCNA LIs showed a low value in the normal rim of the adenoma and normal glands resected as biopsy specimens from adenoma patients. We, therefore, assumed that proliferative activity was suppressed in these cells compared with that in normally functioning glands. In secondary hyperparathyroidism, when the cell component of the parathyroid tissues was divided into five types, PCNA immunoreactivity was lowest in the dark chief cells. Proliferative activity in cells of the oxyphil series was the same or higher than that in the clear chief cells or vacuolated chief cells. When classified according to the structure of the parathyroid glands, cell proliferation was significantly higher in the nodular type than in the diffuse type (maximum LI, 176 +/- 231 vs. 38.3 +/- 55.7; average LI, 120 +/- 188 vs. 24.8 +/- 43.5; mean +/- SD; P < 0.001). More PCNA-immunoreactive cells were found in autotransplanted glands with recurrence than in glands resected during the initial surgery. To summarize the PCNA expression classified according to the pathological types of hyperparathyroidism, the PCNA LIs were highest in secondary hyperplasia (maximum LI, 144 +/- 212; average LI, 96.0 +/- 169) and adenoma (maximum LI, 102 +/- 81.7; average LI, 67.5 +/- 67.7), followed by primary hyperplasia (maximum LI, 25.0 +/- 25.4; average LI, 19.2 +/- 22.2) and normal glands (maximum LI, 13.6 +/- 23.9; average LI, 4.40 +/- 8.90). These findings suggest that the cellular proliferative kinetics of the parathyroid gland differ depending on the type of hyperparathyroidism, glandular structure, and cell components. As the detection method of intranuclear expression of PCNA in cells is too sensitive, we should be careful not to overestimate the number of cells in the proliferative cycle. However, these results could not have been obtained using a conventional method such as DNA analysis by flow cytometry.     

Expression and function of a scavenger lipoprotein pathway in porcine luteal cells

PURPOSE: To evaluate the usefulness and cost-effectiveness of routine preoperative technetium-99m sestamibi-iodine-123 subtraction scanning in patients with parathyroid gland disease. MATERIALS AND METHODS: Tc-99m sestamibi-I-123 subtraction scanning was performed in 65 patients with primary hyperparathyroidism who were referred for evaluation before first surgery. RESULTS: Focal tracer uptake was detected in the mediastinum in two patients who then underwent primary sternotomy; a parathyroid adenoma, anterior to the ascending aorta, was resected in each case. In a third patient, imaging showed tracer uptake above the thyroid gland; this patient underwent resection of an undescended parathyroid adenoma located in the sheath of the right carotid artery. Initial surgery was curative in all patients. Preoperative subtraction scans depicted 56 of 59 (95%) solitary adenomas. Four patients had hyperplasia; two had double adenoma. Imaging findings indicated multiple parathyroid involvement in five of these patients and facilitated location of 12 of 15 (80%) enlarged glands. Four adenomas and two hyperplastic glands that weighed less than 100 mg were detected. The positive predictive value for any suspected location was 96%. Average surgery time was reduced from 120 to 90 minutes. CONCLUSION: Preoperative subtraction scanning is useful in planning parathyroid surgery and appears to be cost-effective.     

The effect of inorganic pyrophosphate on the transport of oleanolic acid monoglycosides into vacuoles isolated from Calendula officinalis leaves

OBJECTIVE: The objective of our study was to determine the value of using color and power Doppler sonography to reveal extrathyroidal feeding arteries in the detection of abnormal parathyroid glands. SUBJECTS AND METHODS: Forty-four patients with primary hyperparathyroidism were imaged prospectively with high-resolution gray-scale, color flow, and power Doppler sonography. The presence of extrathyroidal arteries supplying the adenomas was noted. All patients underwent subsequent neck exploration. The locations of the abnormal glands were recorded. RESULTS: At surgery, 51 abnormal parathyroid glands were removed in the 44 patients. Sonography correctly revealed an adenoma in 40 of the 44 patients. Likewise, sonography revealed 42 of the 51 adenomas. Nine false-negative and two false-positive interpretations of the sonograms were made. Thus, overall sensitivity was 83%, specificity was 98%, and accuracy was 94%. Three of the false-negative interpretations were ectopic glands within the superior mediastinum. Excluding these three glands from analysis, the sensitivity for detection of adenomas within the neck was 88%, specificity was 98%, and accuracy was 95%. An extrathyroidal artery leading to a parathyroid adenoma was seen in 35 of the 42 adenomas revealed by sonography. The presence of an extrathyroidal artery leading to an adenoma was found to aid in the detection of an otherwise inconspicuous parathyroid gland in five patients, which improved sensitivity from 73% to 83%. CONCLUSION: Prominent vessels supplying parathyroid adenomas are frequently revealed by color flow and power Doppler sonography. These vessels can serve as "road maps" to abnormal parathyroid glands.     

Primary diffuse microscopical hyperplasia of the parathyroid glands: surgical importance

In two of 182 patients with verified primary hyperparathyroidism, microscopical hyperplasia was present in all parathyroid glands that were normal in size or only slightly enlarged. All parathyroid glands in another two patients showed microscopical hyperplasia and varied from a normal size of 190 mg. In seven additional patients, microscopical hyperplasia was present in one, several, or all parathyroid glands, which varied in weight from normal to 350 mg. Familial hyperparathyroidism or multiple endocrine neoplasia was evident in five of 11 patients. Contributing to difficulties was the experience in five patients in whom removal of mildly enlarged parathyroid glands corrected hypercalcemia, but definite microscopical abnormalities were not evident by routine histologic study of the glands. Thus, there appears to be a spectrum of abnormalities relative to size and microscopical changes in parathyroid glands of patients with primary hyperparathyroidism. The surgeon should be aware of these patterns of parathyroid hyperplasia that require a search for a fifth parathyroid gland and a subtotal parathyroidectomy.     

Surgery in primary hyperparathyroidism

Data were reviewed on 26 patients suffering from primary hyperparathyroidism (PHPT). The diagnosis of PHPT is increasing in frequency, due to greater awareness and better methods of detection. Delay in recognition has gradually decreased, thus permitting earlier treatment. No single test or any combination of tests can be considered satisfactorily pathognomonic of PHPT. Hypercalcemia is the most satisfactory finding suggestive of PHPT. Cervical exploration should be an integral part of the diagnostic work-up. Removal of a distinct adenoma is adequate therapy if the other parathyroid glands are normal. Subtotal parathyroidectomy should be performed only in cases of hyperplasia of all parathyroid glands.     

Intrathyroidal parathyroid glands can be a cause of failed cervical exploration for hyperparathyroidism

BACKGROUND: The incidence of intrathyroidal parathyroid glands remains controversial. The purpose of this study was to determine the incidence in a series of patients with hyperparathyroidism. METHODS: Three hundred nine patients underwent parathyroidectomy. Patients were divided into two groups: uniglandular disease versus hyperplasia. RESULTS: Eighteen of 309 patients (6%) had abnormal intrathyroidal parathyroid glands. The incidence was 3% (7 of 222) in patients with uniglandular disease versus 15% (11 of 73) in those with hyperplasia. With a mean follow-up of 54 months, 12 patients are eucalcemic, 5 have persistent hypocalcemia, and 1 has recurrent hypercalcemia. There were no recurrent laryngeal nerve injuries. CONCLUSIONS: These data suggest that an intrathyroidal adenoma is an uncommon cause of failure, whereas abnormal intrathyroidal parathyroid tissue may be a more common cause of failure in patients with hyperplasia.     

Nonadenomatous thymic unencapsulated parathyroid tissue as a cause of persistent primary hyperparathyroidism

Primary hyperparathyroidism may be caused by ectopic intrathymic parathyroid adenomas or hyperplastic parathyroid glands. The association of the ectopic inferior parathyroid glands and the thymus is due to their common embryologic origin from the third pharyngeal pouch. We report a case of primary hyperparathyroidism due to an unusual pathologic parathyroid gland formation: nonadenomatous thymic unencapsulated parathyroid tissue. Two unsuccessful neck exploration revealed only two normal parathyroid glands within the cervical area. Radiologic imaging studies failed to localize an ectopic parathyroid adenoma. Mediastinal exploration and thymectomy showed one small focus of unencapsulated hypercellular parathyroid tissue expanding peripherally along the septa of thymic adipose tissue. The hyperparathyroidism resolved with the surgical procedure.     

Depressed expression of calcium receptor in parathyroid gland tissue of patients with hyperparathyroidism

The factors involved in abnormal parathyroid cell secretory function and growth in patients with primary (I degree) and secondary (II degree) hyperparathyroidism are still incompletely understood. We compared the expression of the calcium-sensing receptor (CaR) at the gene message and the protein level in parathyroid tissue obtained from patients with I degree non-uremic or II degree uremic hyperparathyroidism with that in normal parathyroid tissue, using in situ hybridization and immunohistochemistry techniques. The expression of the CaR mRNA and protein was reduced in most cases of I degree adenoma and II degree hyperplasia, compared with strong expression normal parathyroid tissue. In II degree hyperparathyroidism, expression of both receptor mRNA message and protein was often particularly depressed in nodular areas, compared with adjacent non-nodular hyperplasia. Decreased Ca-R expression in adenomatous and hyperplastic parathyroid glands would be compatible with a less efficient control of PTH synthesis and secretion by plasma calcium than in normal parathyroid tissue.     

Parathyroid hyperplasia in primary hyperparathyroidism: a review of 85 cases

Parathyroid hyperplasia of all four glands was found to be the cause of primary hyperparathyroidism in 85 of 557 cases seen at the Massachusetts General Hospital between 1930 and 1973. There were 66 cases of chief cell hyperplasia and 19 cases of clear cell hyperplasia that were grossly, microscopically, and ultrastructurally distinct. Although the clinical findings overlap, there are several differences in the signs and symptoms between these two forms of hyperplasia. Both types are treated by subtotal removal of all the parathyroid tissue. Removal of insufficient tissue has left residual hyperparathyroidism in 45% of those with chief cell hyperplasia and 11% of those with clear cell hyperplasia after what was thought to be definitive surgery. Postoperative hypoparathyroidism was found in 15% of the patients with chief cell hyperplasia and in none with clear cell hyperplasia. These findings further suggest that removal of three and one-half glands in the more than 86% of patients with one gland involvement (adenoma or carcinoma) as the cause of primary hyperparathyroidism is unwarranted.     

Preoperative parathyroid gland localization with technetium-99m sestamibi in secondary hyperparathyroidism

Technetium-99m sestamibi scintigraphy has become a valuable tool in locating parathyroid glands in patients with primary hyperparathyroidism. The aim of this study was to evaluate its usefulness in secondary hyperparathyroidism. Twenty patients were injected intravenously with 740 MBq of 99mTc-sestamibi and images were obtained at 15 min and 2 h post injection. All patients underwent parathyroid ultrasonography (US) as well as bilateral surgical neck exploration and 64 parathyroid glands were removed. US revealed at least one enlarged gland in 15/20 patients (75%), while 99mTc-sestamibi scintigraphy showed focal areas of increased uptake in at least one gland in 17/20 patients (85%). When imaging results for all glands were evaluated according to surgical results, sensitivity was 54% for parathyroid scintigraphy and 41% for US, and specificity was 89% for both imaging techniques. There was a discrepancy between the two imaging modalities in 28 glands (35%). The mean surgical weight of US-positive glands (1492+/-1436 mg) was significantly higher than that of US-negative glands (775+/-703 mg) (P<0.05). However, there were no significant differences in weight between sestamibi-positive and sestamibi-negative glands. When only sestamibi-positive glands were considered, a positive correlation between uptake and weight was found (r=0.4, P<0.05). In conclusion, parathyroid US and 99mTc-sestamibi scintigraphy are complementary imaging techniques in the preoperative localization of abnormal parathyroid glands in patients with secondary hyperparathyroidism. The limited sensitivity of the techniques means that patients will still require bilateral neck exploration; therefore routine preoperative parathyroid scanning in renal patients is not justified.     

Value of ultrasonography, CT and MR imaging in the diagnosis of primary hyperparathyroidism

PURPOSE: To evaluate the significance of preoperative localization of abnormal parathyroid glands to the surgical outcome in patients with primary hyperparathyroidism. MATERIAL AND METHODS: Thirty-nine patients with primary hyperparathyroidism were studied preoperatively with US (39 patients), CT (30 patients) and MR imaging (18 patients). The overall diagnostic accuracy for US was 87%, CT 66% and MR 94%. In patients with a single parathyroid adenoma US was the most cost-effective localization technique with a detection rate of 96%. CT had a lower detection rate (78%) but was of particular value for fairly large ectopic adenomas in the root of the neck. MR imaging was a good confirmatory test (93%). In patients with multiple gland disease (primary hyperplasia and multiple adenomas), no single localization study alone was sufficient. Combination of all 3 studies, however, alerted the physician to the presence of disease in more than one gland in 87% of these patients. CONCLUSION: US, CT and MR imaging followed by surgery performed by an experienced surgeon provided good clinical results in 39 patients with primary hyperparathyroidism. Preoperative localization was especially useful in patients with primary parathyroid hyperplasia or multiple adenomas and in patients with ectopic parathyroid adenomas in the root of the neck. We recommend identification of all abnormal parathyroid glands prior to surgery.     

The role of nuclear magnetic resonance in the diagnosis of pericardial diseases]

The hypothesis that due to the high prevalence of solitary adenoma and the accuracy of modern imaging techniques it should be possible to cure a considerable number of patients by direct adenomectomy through a minimally invasive approach was tested in a consecutive series of 66 patients with primary hyperparathyroidism. Preoperative parathyroid imaging consisted of a combination of (Doppler) ultrasound and spiral computed tomography with cine-loop reconstruction potentiality. If only one parathyroid adenoma was identified preoperatively, a minimally invasive approach was advised. If more than one adenoma was located, or when the imaging results were equivocal, the patient was advised to undergo a conventional bilateral neck exploration. Sixty-six patients (54 female, 12 male) with a median age of 60 years and a median serum calcium of 2.90 mmol L(-1) were studied. Fifty-one of these patients underwent minimally invasive surgery, which was successful in 49 patients, while conversion to conventional neck exploration was necessary in two patients. Conventional neck exploration was chosen for the other 15 patients. Six of these proved to have multiglandular disease or a retro-sternal adenoma, while in nine patients only one parathyroid adenoma was found. All patients became normocalcaemic postoperatively. Morbidity consisted of a transient unilateral vocal cord paralysis in one patient. These results support the original hypothesis: successful minimally invasive surgery was possible in 74% (49 of 66) of patients, thus avoiding conventional neck exploration. This strategy further simplifies the operative treatment of primary hyperparathyroidism without loss of efficiency.     

The role of ultrasonography in the diagnosis of enlarged parathyroid glands

The ultrasonographic diagnosis of parathyroid glands was introduced by the Japanese in 1975. Only after more perfect machines have been introduced, first of all by advancement of "real-time" technique, this method started being used as a routine. The paper shows results of ultrasonographic investigation in 200 patients separated into two groups. In the first group 100 patients were examined with a clinical suspect of primary hyperparathyroidism from which in 30 the existence of parathyroid gland adenoma was diagnosed. Scintigraphy of parathyroid glands was performed in the smaller group of patients; the comparison of these two methods was done, and in 77.7% cases coincidence was found. In the group of 10 operated patients comparison of the two mentioned methods was carried out, with surgical or pathohistologic findings and the coincidence was complete. In the second group 100 patients were examined belonging to the chronical program of hemodialysis, from which in 24 cases existence of swollen parathyroid glands was found. Comparison of ultrasonographic and scintigraphic findings was also done and the coincidence was 68.75%. At the end, the importance of ultrasonography in the first diagnostic stage of swollen parathyroid glands was pointed out.     

Functioning oxyphil adenoma of parathyroid gland. An ultrastructural and biochemical study

Oxyphil cells and oxyphil cell adenomas of parathyroid glands are, in most instances, regarded to be nonfunctioning. Although 21 cases of hyperparathyroidism associated with parathyroid oxyphil cell adenoma have been reported, secretion of hormone by these tumors has not been conclusively demonstrated. A parathyroid adenoma, diagnosed by light microscopy as oxyphil type, together with the results from ultrastructural and biochemical studies of the patient's adenomatous tissue, are reported here. The patient, a 64-year-old male, was found to have elevated serum calcium, low serum phosphorus, and elevated serum immunoreactive parathormone: findings consistent with hyperparathyroidism. After excision of two small normal-appearing glands and one greatly enlarged (1.9 g) parathyroid gland, those laboratory values returned to normal. Light microscopy of the enlarged parathyroid indicated that it consisted almost entirely of an oxyphil adenoma. Electron microscopy revealed that the adenoma was composed mainly of mitochondria-rich oxyphil cells but also of interspersed transitional oxyphil cells and rare scattered chief cells. Golgi zones, rough endoplasmic reticulum, and prosecretory and secretory-like granules were observed in some oxyphil cells, in most transitional oxyphil cells, and in the infrequent chief cells. Thus, many of these cells appear to contribute to the production and secretion of parathormone. Biochemical studies performed directly on the adenomatous tissue demonstrated that it was able to synthesize proparathormone and parathormone, although the proportion of hormonal peptide synthesis relative to that of the total protein synthesis in this tissue was much smaller (0.9%) than that found in normal parathyroid tissue (5.7%). There was a small increase in immunoreactive parathormone when the adenoma tissue was incubated in a low-calcium medium. These findings indicate that this oxyphil adenoma of the parathyroid gland synthesized and secreted parathormone, apparently to some extent autonomously, but suggest that its capacity to do so was largely dependent on its component of cells other than fully developed oxyphil cells, such as transitional oxyphil cells.     

Case report: Fracture of an ossified Achilles tendon - MR appearances

Hyperparathyroidism is a potentially life-threatening disease, caused primarily by parathyroid adenoma. Surgical excision of the tumor, with consequent return of calcium levels to the normal range, is considered the treatment of choice. Within the last few years, several reports have described the destruction of parathyroid tissue using ultrasonically guided injection of 96% ethanol into pathologic parathyroid glands, resulting in successful regulation of both primary and secondary hyperparathyroidism. The procedure was reported as an alternative to operative treatment for patients as high surgical risk, such as the elderly and the critically ill. We report the occurrence of transient Horner's syndrome and vocal fold paralysis after successful injections of ethanol into a parathyroid adenoma, and discuss the implications and restrictions of the procedure in view of the medical literature.     

Cost utility of routine imaging with Tc-99m-sestamibi in primary hyperparathyroidism before initial surgery

Tc-99m-sestamibi has been shown to localize parathyroid adenomas effectively, but controversy continues as to the use of this scan before initial surgery for primary hyperparathyroidism. We analyzed the cost utility of obtaining this study before initial surgery for primary hyperparathyroidism. Twenty-two consecutive patients with primary hyperparathyroidism underwent dual-phase Tc-99m-sestamibi scan before initial bilateral neck exploration. Surgical findings were correlated with the results of sestamibi scan. There were 15 women and 7 men, with a mean age of 50.5 years (range, 22-76). Preoperative mean total calcium was 11.74 mg/dL (range, 10-15), ionized calcium was 6.19 mg/dL (range, 5.2-7.7), and intact parathyroid hormone was 153.5 pg/mL (range, 83.1-551). Postoperative mean ionized calcium was 4.56 mg/dL (range, 4.1-5.57). Twenty sestamibi scans had a positive localization, and 2 scans had no localization. At surgery, 18 solitary adenomas, 3 diffuse hyperplasias, and 1 patient with four normal parathyroid glands were found. Sixteen sestamibi scans were true positive (solitary adenoma), 4 scans were false positive (2 diffuse hyperplasia, 1 wrong side, and 1 lymph node), 1 negative scan was true negative (diffuse hyperplasia), and 1 negative scan was false negative (adenoma). One patient (four normal glands) at the second operation had a supernumerary fifth gland adenoma excised from the mediastinum. Preoperative Tc-99m-sestamibi scan did not offer any advantage when a complete bilateral neck exploration is performed. Sixteen of (84%) adenomas were correctly localized, but 18 of 19 adenomas were in the neck and were easily found. The 1 ectopic adenoma was not found by scanning or with initial surgery. The 4 of 22 (18%) false-positive localizations and the 2 of 22 (9%) negative scans contributed nothing to the surgery. Of the 22 localizing sestamibi scans, surgery was not altered to affect the outcome. At a cost of $550 per sestamibi scan and with the error inherent in the scan, it is not cost effective to obtain Tc-99m-sestamibi scan before initial surgery for primary hyperparathyroidism.     

Collagen deposition and mechanical strength of colon anastomoses and skin incisional wounds of rats

BACKGROUND: The purpose of this study was to prospectively evaluate parathyroid localization using technetium-99m-sestamibi (MIBI). STUDY DESIGN: Technetium-99m-sestamibi scintigraphy was performed in 124 patients with hyperparathyroidism and the results were correlated with serum calcium and parathyroid hormone (PTH) levels, weight, location, and pathology of parathyroid tissue, and associated thyroid abnormalities. RESULTS: Hyperparathyroidism was primary in 118 patients, secondary in four patients, and tertiary in two patients. The parathyroid pathology was a solitary adenoma in 95 patients (77 percent), double adenoma in five (4 percent), hyperplasia in 14 (11 percent), carcinoma in one (1 percent), and unconfirmed in nine (7 percent) who underwent noncurative parathyroidectomy. Associated thyroid disease was present in 29 (23 percent) patients. Fourteen patients (11 percent) had undergone previous parathyroid exploration. The mean calcium level was 11.4 +/- 0.8 mg/dL (range, 8.3 to 13.7 mg/dL) and the mean adjusted PTH level was 395 +/- 702 (range, 70 to 4,331). The sensitivity and positive predictive value of MIBI scintigraphy were 81 and 89 percent, respectively, in patients with a solitary adenoma and 37 and 100 percent, respectively, in patients with multiglandular disease. The mean adjusted PTH level was higher in patients with true-positive scans compared with false-negative scans (440 +/- 628 compared with 243 +/- 499, p > 0.05). The mean adenoma weight was 1,877 +/- 3,212 mg in patients with a true-positive scan compared with 485 +/- 296 mg with a false-negative scan (p > 0.05). CONCLUSIONS: The sensitivity and positive predictive value of MIBI scintigraphy is comparable to or better than the results reported for other localization procedures. Its lack of sensitivity for detection of multiglandular disease precludes its use in lieu of routine bilateral neck exploration in the management of patients with hyperparathyroidism.     

Distribution of the solitary adenoma over the parathyroid glands

One hundred and ten patients with primary hyperparathyroidism were studied, in which a normal parathyroid gland was found on the same side as an adenoma (both confirmed by histological examination), and the upper or lower location could clearly be defined during surgery. The distribution of the adenomas over the upper and lower glands was unequal: 61.8 per cent in the superior versus 38.2 per cent in the inferior position. Statistical analysis revealed that this is not a random distribution (p = 0.013). The explanation of this relative predilection is unknown. The finding should not influence the surgical procedure for primary hyperparathyroidism.     

Surgical significance of supernumerary parathyroid glands in renal hyperparathyroidism

In secondary hyperparathyroidism (2HPT) fundamentally all parathyroid glands, including supernumerary glands, become hyperplastic, and stimulation of parathyroid glands continues after parathyroidectomy (PTx). Therefore supernumerary glands have special significance during surgery for 2HPT, whether persistent or recurrent HPT. In the present study 570 patients underwent initial total PTx with a forearm autograft. The frequency, type, location, histopathology, and clinical significance of the supernumerary glands were evaluated. At the initial operation 90 supernumerary glands were removed from 82 to 570 patients (14.4%); 12 patients (2.1%) required extirpation of supernumerary glands for persistent/recurrent HPT. Altogether 104 supernumerary glands were identified at operation in 94 of the 570 patients (16.5%). Among these 104 glands, 25 (24.0%) were of the rudimentary, or split, type and 79 (76.0%) of the proper type. Supernumerary glands were most frequently identified in the thymic tongue (53/104, 51.0%); 32 (60.4%) of these 53 glands were identified only microscopically. In 6 of the 570 cases (1.1%), reoperation was required for persistent HPT due to supernumerary glands located in the mediastinum, and 6 patients underwent neck reexploration for recurrence. Histopathologically, 61 of 104 (58.7%) supernumerary glands, including 36 glands recognized only microscopically, showed diffuse hyperplasia, and 43 (41.3%) displayed nodular hyperplasia. Residual small supernumerary glands with diffuse hyperplasia have the potential to be transformed to nodular hyperplasia during long-term hemodialysis. Therefore all parathyroid glands including supernumerary glands should, if possible, be removed at the initial operation. Routine removal of the thymic tongue and careful examination of the regions surrounding the lower poles of the thyroid, especially on the left side, are important steps in the surgical treatment.