Retrospective analysis of the association of nodular goiter with primary and secondary hyperparathyroidism

BACKGROUND

The association of hyperparathyroidism (HPT) with thyroid disease has long been known, but the mechanisms underlying such an association have not yet been clarified.

OBJECTIVE

To elucidate the main factors determining this combination of endocrine diseases, in a retrospective multicenter study.

METHODS

We retrospectively reviewed all patients referred for parathyroid scintigraphy in the period 1990-1999. A total of 487 patients in the age range 17-65 years were selected for the analysis (339 women and 148 men); group A included 241 patients with primary and group B 246 patients with secondary HPT.

RESULTS

A total of 124/241 patients in group A (51.5%), but only 92/246 patients in group B (38.2%) had thyroid disorders (notably nodular goiter) associated with HPT (P=0.0035). Thyroid disorders were evenly distributed throughout the entire 17-65 years age range in group A, but 17-40-year-old patients in group B had significantly fewer thyroid disorders than the older patients of the same group (15.5% compared with 43.3%, P<0.002), as expected in a general population. In patients with primary HPT there was no difference in the prevalence of thyroid disease between women and men, whereas the ratio of women to men in secondary HPT patients with thyroid disease was about 3:1.

CONCLUSIONS

These results demonstrate an increased prevalence of nodular goiter in patients with primary rather than secondary HPT, and are consistent with a possible role of increased endogenous calcium concentrations (a hallmark of primary, but not of secondary, HPT) as a goitrogenic factor in patients with HPT.

Evaluation of hypertensive patients with a solitary kidney using captopril renal scintigraphy with 99Tcm-MAG3

The study aimed to evaluate the safety and reliability of captopril renal scintigraphy (CRS) for diagnosing functionally significant renal artery stenosis (RAS) in hypertensive patients with a solitary kidney. Radionuclide studies were carried out using 100 MBq 99Tcm-mercaptoacetyl triglycine (MAG3), 1 h after administration of 50 mg captopril, and repeated in baseline condition when abnormalities were observed in the provocative study. Scintigraphic diagnosis of RAS was based on analysis of captopril-induced changes of the radiorenographs. Overall, 12 patients with a solitary kidney were investigated, and scintigraphic results compared to angiographic findings. All five patients with positive CRS showed an RAS > 50%, whereas only one of the seven patients with negative CRS was affected by RAS. A significant fall in mean arterial pressure was recorded after captopril administration (123 +/- 12 mm Hg before versus 108 +/- 11 after), but no serious side effects were observed. Our results demonstrate that captopril-induced modifications of the renogram could effectively be used to diagnose the presence of RAS. Captopril renal scintigraphy may therefore be suggested as a reliable and safe noninvasive approach to evaluate hypertensive patients with a solitary kidney.

Seronegative spondyloarthropathy associated with megarectum

In this report we describe a case of a 19-year-old man with a two-year history of polyarthritis affecting the lower limbs and dactylitis of the toes. His clinical picture fulfilled the new European diagnostic criteria for spondyloarthropathies. Systemic examination revealed a big mass in the left iliac fossa that was found to be due to an acquired functional megacolon. Complete remission of the joint involvement was obtained by treating the bowel disease.

Spread and distribution of 5-ASA colonic foam and 5-ASA enema in patients with ulcerative colitis

Rectal treatment with enemas, foams, and suppositories is the most efficient method of delivering an adequate quantity of locally active drugs to the distal colon. In a pilot study carried out by colonoscopy in four patients, it was observed that 4 g 5-ASA in 20 ml foam spread up or beyond the splenic flexure and more extensively than 2 g 5-ASA in 10 ml foam. Therefore we have undertaken a study in order to compare by scintigraphy the colonic distribution of 4 g 5-ASA foam versus 4 g 5-ASA in 100 ml liquid enemas in 10 patients with ulcerative colitis using a crossover randomized design. Both preparations were labeled with 100 MBq [99mTc]sulfur colloid before administration. Anterior scans were taken at intervals for 4 hr. Activity, expressed as a percentage of total radioactivity, was measured in the rectum, sigmoid, descending, transverse, and ascending colon. Six patients had the same extent of spread with the two formulations; in three patients with foam and in one patient with enema a greater spread was observed. The foam reached the upper limit of disease in all cases, while enema failed in two cases. The maximum spread with foam was observed within 30 min in nine of 10 patients compared with seven of 10 after enema. Compared to enema, foam distributes more uniformly and seems to persist longer in the descending and sigmoid colon. The 5-ASA colonic foam shows some more favorable characteristics than enema for the local treatment of left-sided ulcerative colitis.

Cerebral SPECT with 99mTc-HMPAO in extracranial carotid pathology: evaluation of changes in the ischemic area after carotid endarterectomy

The authors report their experience in studying patients undergoing carotid endarterectomy with simple photon emission computed tomography (SPECT). This technique made it possible to identify areas of preoperative cerebral hypoperfusion in 54.8% of the patients which had a good correlation with neurological symptoms. To distinguish gradual changes in the ischemic lesions, a method of assessing the surface of the hypoperfused areas was adopted. In addition, SPECT made it possible to detect a greater number of hypoperfused areas even in sites other than those revealed by CT. Moreover, there was good correlations between the SPECT data and the grade and site of the carotid lesion and the data provided by some intraoperative monitoring procedures. The Authors therefore propose the use of SPECT in the evaluation of patients with cerebrovascular insufficiency following a carotid disease.

Elimination diet in the treatment of selected patients with hypersensitivity vasculitis

We have evaluated the effects of an elimination diet in 5 patients with hypersensitivity vasculitis and a personal or family history of allergy. The presence of autoimmune disorders, infections and neoplastic diseases was excluded on the basis of physical examination, clinical history and laboratory data. Three patients had elevated serum immune complexes and evidence of complement consumption before the oligoantigenic diet. In one patient food allergy was diagnosed on the basis of a positive and concordant challenge test, skin prick test and RAST. The study consisted of a 3 week elimination diet, followed by open and double blind challenge tests with specific foods and additives. Four patients achieved a complete remission and one patient experienced great improvement on the elimination diet. In three cases the vasculitis relapsed following the introduction of food additives; in one case with the addition of potatoes and green vegetables (i.e., beans and green peas) and in the last case with the addition of eggs to the diet. The offending foods and additives were subsequently eliminated from the usual diet and no relapses were observed in 2 years of follow-up. These results show that in selected patients with a history of allergy, hypersensitivity vasculitis can be triggered and sustained by food antigens or additives.

Use of technetium-99m-MAG3 for renal scintigraphy after angiotensin-converting enzyme inhibition

Technetium-99m-mercaptoacetyltriglycine (99mTc-MAG3) was tested in 82 hypertensive patients submitted to renal scintigraphy 1 hr after oral premedication with 50 mg of Captopril. Baseline studies were obtained only for those patients showing abnormal findings in the provocative study. All patients underwent renal arteriography. Sensitivity and specificity for the detection of renal artery stenosis (RAS) greater than 50% were 89% and 91%, respectively. After Captopril administration, tracer parenchymal transit time increased significantly in ischemic kidneys (334 +/- 93 sec in baseline conditions versus 468 +/- 96 sec after Captopril, p less than 0.001) but not in kidneys with no RAS or RAS less than 50% (243 +/- 46 sec versus 271 +/- 95 sec, p = ns). False-positive responses were mostly bilateral and associated with a marked decrease in blood pressure. Technetium-99m-MAG3 is an effective compound for detecting RAS greater than or equal to 50% with Captopril renal scintigraphy. Performing the provocative test as a first step considerably reduced the number of scintigraphic studies required.

[Prevalence of food allergy in patients with urticaria-angioedema syndrome]

We have studied 239 patients, 53 males and 186 females, mean age 31.9, affected by urticaria-angioedema syndrome. Fifty-three patients didn't complete the study. One-hundred-three of the other 186 patients went on elimination diet: 111 patients suffered from chronic urticaria-angioedema syndrome and 21 subjects suffered from acute syndrome. Eighty-one out of the 132 patients obtained good results from dietetic management (p less than 0.001). Double blind challenge test was positive in 42 subjects: 29 patients suffered from Food Allergy and 13 patients from Food Intolerance. Thus, the prevalence of Food Allergy in patients who completed dietetic management was 21.9% (29 patients out of 132). If we evaluate all the 186 patients affected by urticaria-angioedema syndrome, the prevalence of Food Allergy is 15.5%.

Diagnostic accuracy of single photon emission computed tomography with thallium-201 for the identification of diseased coronary arteries. Comparison between dipyridamole infusion and exercise stress test

Myocardial perfusion imaging with 201Tl and single-photon emission computed tomography (SPECT) was carried out in two groups of patients, subsequently submitted to diagnostic coronary angiography. SPECT was performed in group 1 (41 patients) after slow i.v. infusion of dipyridamole and in group 2 (162 patients) after tracer injection at maximal ergometric exercise. To evaluate the diagnostic capability of SPECT in the detection of diseased coronary vessels, the left ventricular myocardium was subdivided into 6 segments related to the three major coronary arteries. Sensitivity for the left anterior descending artery was 77% in group 1 and 79% in group 2; specificity was 80% and 96%, respectively. Sensitivity for the right coronary artery was 91% in group 1 and 85% in group 2; specificity was 81% and 73%. For the left circumflex artery sensitivity was 65% for group 1 and 67% for group 2, while specificity was 89% and 88%, respectively. Myocardial SPECT results after ergometric exercise and dipyridamole infusion turned out to be almost superimposable. Dipyridamole stress might be considered appropriate as a provocative test when physical exercise cannot be carried out.

Regional left ventricular ejection fraction with single crystal gammacamera and gated equilibrium technique: repeatability and inter-observer variability

Regional left ventricular ejection fraction calculated by means of gated blood pool scintigraphy was compared with that obtained from contrast ventriculography in a group of 20 patients, submitted to both procedures within a month. To evaluate repeatability both at rest and during stress, a second scintigraphic study was carried out after three weeks, with no change in drug regimen. Inter-observer variability was assessed in a randomly selected subgroup of 16 patients, in whom a computation was repeated by a second operator. Comparison of scintigraphic results showed a satisfactory agreement, and measurement agreement for global left ventricular ejection fraction was very good. As regards interobserver variability, each of the three myocardial segments examined (septal, lateral and infero-apical) showed good agreement. As regards repeatability, global left ventricular ejection fraction, proved readily reproducible both for rest and stress studies, with relatively small differences in observed values. Regional ejection fraction, on the other hand, had a high variability, especially during stress. It is suggested that for regional ejection fraction evaluation, reproducibility studies should be performed in order to better correlate result changes to clinical outcome after medical or surgical therapy.

[Abdominal scintigraphy with leukocytes marked with indium-111 in Crohn disease: clinical importance and prognostic usefulness]

The exact role of 111In leukocyte scanning in the assessment of clinical activity of Crohn's disease (CD) is still a matter of controversy. In our center we studied 22 patients with CD (8 with active disease) with standard 111In labelled mixed leukocyte scans. We determined the extent of the lesion measured as lesion-occupied cells on scanned area and the degree of inflammatory activity assessed as count ratio between the involved region and the iliac crest. Particularly in delayed scans, these scintigraphic parameters showed good correlation with clinical and laboratory indices of disease activity. In our series, only 6 patients had completely negative scans. They were in clinical and laboratory remission, and 5 of them had undergone surgery for CD during the previous year, with no radiological and/or endoscopic findings of recurrence. Among the other 8 patients in clinical remission, 5 had positive early scans, while the rest showed persistent delayed images. Moreover both early and delayed leukocyte scans were positive in 8 cases in which disease was undoubtedly active. A 1-year follow-up was available for 14 patients in clinical remission when 111In-scan was performed. During this period, 3 patients, all of whom had had early and delayed positive 111In-scan, suffered from clinical relapse; no clinical relapses were documented in patients with only 4th hour positive scans. In conclusion, in our series, 111In-scan was also frequently positive in patients in clinical remission; in this patient subset persistent images on delayed scans might suggest the risk of clinical relapse.

[A new sterile generator of Tc 99m. Quality control]

Production has started on a new Tc 99m sterile generator in Italy. We give the results of a series of quality controls in order to have a first evaluation of the product. The elution profile and the volume, activity, pH, aluminium concentration, 99 Mo content and radiochemical purity of the eluate were examined. Radiochemical purity tests were also carried out with some of the more widely used "in vivo" radiopharmaceuticals. The results are in line with the Official Pharmacopeia and good technical standards.

[Use of radioisotopes in the evaluation of coronary disease]

A study on myocardial perfusion through scintigraphy with 201-Tl has been carried on in a group of 57 persons: among them 45 had myocardial infarction and 12 had myocardial ischemia in act. In consideration of this experience, the myocardial scintigraphy with 201-Tl seems to be a valid investigation method to support the electro-vectocardiography when evaluating, bloodlessly, ischemical cardiopathies. In general, the correlation between electro-vectorcardiographic and scintigraphic data has been satisfactory. Referring to stroken parts, we can say that also those cardiac sectors usually very difficult to be explored with other radio elements such as 131-CS and 42-K, have been adequately studied with 201-Tl. To sum up, we can say that scintigraphic investigation of myocardium with 201-Tl is certainly a valid blood-less method to diagnose ischemical cardiopathy with the advantage to be also a useful diagnostical element for the evaluation of the microcirculation.