Matteo Zingrillo

Pre-Cushing’s syndrome not recognized by conventional dexamethasone suppression-tests in an adrenal “incidentaloma” patient

Pre-Cushing’s syndrome has been recently diagnosed in 6–12% of patients affected with incidentally discovered adrenal masses. Some of these patients have been described to show transient hypoadrenalism after surgery, similarly to those affected with overt Cushing’s syndrome. We studied a 70-year-old male patient with a large left adrenal mass, incidentally discovered, who displayed 24-h urinary free cortisol levels at the upper limit of the normal range, normal dexamethasone overnight and low-dose suppression tests and not suppressed ACTH levels, increased 17-hydroxyprogesterone response to ACTH stimulation and low upright plasma renin activity with normal serum aldosterone levels; furthermore, DHEAS level was low and 75 Selenium-cholesterol scintigraphy showed unilateral uptake concordant with the side of the mass. Soon after left adrenalectomy, he complained of acute hypoadrenalism requiring cortisol replacement therapy: ten months after surgery he is still hypoadrenal. Moreover, stimulated 17-hydroxyprogesterone and plasma renin activity in clino- and orthostatic posture have become normal. We propose that conventional dexamethasone suppression-tests may be not enough sensitive in this kind of patients and that in selected cases the absence of controlateral uptake at scintigraphy may be more reliable in predicting post-surgical hypoadrenalism.

Global skeletal uptake of technetium-99m methylene diphosphonate in female patients receiving suppressive doses of L-thyroxine for differentiated thyroid cancer.

Abstract. This study was carried out in order to investigate the possible detrimental effects on bone of levothyroxine (l-T4) suppressive therapy in female patients who had undergone surgery for differentiated thyroid cancer (DTC). Twenty female (14 premenopausal and 6 postmenopausal) patients receiving l-T4 suppressive therapy for DTC were studied. The sample was selected in such a way as to avoid factors influencing bone metabolism other than l-T4. All patients were monitored by sensitive thyroid-stimulating hormone, free triiodothyronine and free thyroxine assays throughout the follow-up. Nineteen healthy (12 premenopausal and 7 postmenopausal) matched women served as controls. In all subjects bone turnover was evaluated by the measurement of global skeletal uptake of technetium-99m methylene diphosphonate (GSU); bone mineral density (BMD) was measured by quantitative computed tomography at the lumbar spine (LS) and by dual-energy X-ray absorptiometry both at the LS and at three femoral sites: the femoral neck, Ward’s triangle and the greater trochanter. No significant difference was found in either GSU or BMD between patients (treated for an average period of 68 months) and controls in the whole sample or in any subgroup. Furthermore, no correlations were found between either GSU or BMD and the duration of therapy, daily doses of l-T4 or results of thyroid function tests. Our data show that carefully monitored l-T4 therapy does not influence skeletal turnover (directly reflected by GSU) or the bone density of the spine and femur.

Cold benign thyroid nodule volume reduction predictability after percutaneous ethanol injection.

OBJECTIVE To determine the effect of percutaneous ethanol injection (PEI), a suppressive therapy for cold benign thyroid nodules (CBNs), on cytology. STUDY DESIGN The study group consisted of 31 CBNs, treated with PEI for 1 year, aspirated before and while the patients were on suppressive therapy. A control group consisting of 22 patients, whose nodule characteristic, PEI treatment and follow-up were similar to those of the study patients group, was monitored to confirm the results. By analogy with a similar study, the following factors were considered: an initial volume of the CBNs > 25 mL, abundant colloid, degree of cellular hyperplasia and presence ofdegenerative changes. To verify these hypotheses, we tested the differences using the t test for the initial volume and the Mann-Whitney U test for the remaining features. RESULTS The study has proved the unpredictability of the volume reduction in a single nodule on the basis of cytologic evaluation. CONCLUSION The lack of cytologic features that can be considered statistically predictive of large nodule reduction as a result of PEI treatment confirms that fine needle aspiration cytology may help establish the correct diagnosis.

TSH receptor antibodies and ultrasonography in Graves' disease

Sirs, Rieu and colleagues (1994) have presented some stimulating data concerning the effect of antibodies to TSH receptors on some ultrasonographic parameters in patients with Graves’ disease. We would like to raise some questions regarding this paper. The authors do not indicate how many patients were excluded at initial recruitment on the basis of a negative TSH receptor antibody (TRAb) level. In different studies the proportion of TRAb negative patients (with a less specific radioreceptor assay) was shown to range between 15 and 30% of untreated patients with Graves’ disease (Hensen et al., 1984; Morris et al., 1988). Were these ‘negative’ patients studied ultrasonographically? If so, were the data compared with those from ‘positive’ patients? Another question concerns thyroid nodularity. The reported proportion of patients with at least one nodule, 44.2%, was surprisingly high, compared with 4.7% of patients with Graves’ disease studied using a 5-MHz probe (Miiller-Gartner et al., 1986). In a study of ultrasonographic appearances at different stages of Graves’ disease using a 7-5-MHz probe, we found thyroid nodules in only 1/32 patients with Graves’ disease at the onset (3.1%) and, respectively, in 6/25 patients during the first thionamide cycle (24%) and in 11/38 (29%) patients relapsing after the first cycle and during a new period of thionamide therapy (Zingrillo et al., 1993). In the Miiller-Gartner series 12/256 patients with Graves’ disease and characteristically low echogenic ultrasound appearance showed a single or several intrathyroidal focal alterations with high echogenicity; these foci were proved to be unresponsive to TSH-receptor stimulation by Graves’ immunoglobulins. In conclusion, we feel that the authors are correct as far as the correlation between TRAb titres and thyroid volume in Graves’ disease is concerned, but we disagree with them about the correlation between TRAb titres and nodular volume, since nodular tissue seems to be insensitive to autoimmune stimulation. Finally, we wonder whether the high percentage of thyroid nodules discovered by the authors might be due to a misinterpretation of thyroid ultrasonographic appearances. In our experience, some patients with the typical hypoechogenic pattern of Graves’ disease have ‘scattered’ hypoechoic areas in the whole thyroid parenchyma, some-