Post-mortem toxicology in the diagnosis of sudden death in young and middle-aged victims

OBJECTIVE

We aimed to investigate the impact of the toxicological results found in cases of sudden death (SD) and to correlate the clinical, autopsy and genetic findings with the toxicology results.

MATERIALS AND METHODS

Consecutive SD in people aged between 16 and 50 years with medico-legal autopsies and toxicology studies were included over a 3-year period. The comparison between the toxicological data and demographic characteristics, clinical circumstances, autopsy, and genetic results were taken into account.

RESULTS

101 cases were finally included. They were predominately males (84%) and the mean age was 39.8 years. 52 (51.5%) cases had positive toxicological findings and in 25 cases (24.8%), toxic compounds were considered the first cause of death. Ethanol was the most frequently identified agent (69%), following by licit drugs (56%) and drugs of abuse (39%). Cases with positive toxicology were younger than those with negative results (37.9±9.1 vs. 41.9±7.8; p=0.02). Patients with more than 3 comorbidities showed an association with positive toxicological results (n=14 vs. n=3; p=0.017). The genetic study was performed in 70 (69.3%) SD cases. We identified pathogenic or likely pathogenic variants in 17.1% cases and uncertain significance variants in 42.8% cases. 58% of these variants were probably related to the cause of death.

CONCLUSIONS

A large fraction of SD victims had positive toxicological findings and a quarter of deaths were directly caused by toxic substances. The identification of the factors that trigger SD provides a good approach to contribute in avoiding future episodes.

Phenotypic characterisation of T-lymphocytes in COPD: abnormal CD4+CD25+ regulatory T-lymphocyte response to tobacco smoking

Tobacco smoking induces an inflammatory response in the lungs of all smokers but, for reasons that are still poorly understood, only a proportion of them develop chronic obstructive pulmonary disease (COPD). Recent evidence indicates that this inflammatory response persists after smoking cessation, suggesting some type of auto-perpetuation mechanism similar to that described in autoimmune disorders. T-lymphocytes (CD4+ and CD8+) have been implicated in the pathogenesis of both COPD and several autoimmune processes. A subtype of regulatory CD4+ T-cells expressing CD25 (Tregs) plays a critical role in the maintenance of peripheral tolerance and the prevention of autoimmunity, but their potential role in COPD has not been explored. The present study sought to evaluate maturation (CD45RA/CD45R0) and activation markers (CD28) of T-lymphocytes and to explore potential Treg abnormalities in COPD. Flow cytometry was used to characterise T-lymphocytes obtained from blood and bronchoalveolar lavage fluid (BALF) in 23 patients with moderate COPD, 29 smokers with normal lung function and seven never-smokers. The main findings were that in BALF: patients with COPD showed higher CD8+CD45RA+ and lower CD8+CD45R0+ than smokers with normal lung function; and compared with never-smokers, smokers with preserved lung function showed a prominent upregulation of Tregs that was absent in patients with COPD. These observations indicate a final maturation-activation state of CD8+ T-lymphocytes in chronic obstructive pulmonary disease and, for the first time, identify a blunted regulatory T-cell response to tobacco smoking in these patients, further supporting a potential involvement of the acquired immune response in the pathogenesis of the disease.

Intracellular cytokine profile of T lymphocytes in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterized by an excessive inflammatory response to inhaled particles, mainly tobacco smoking. T lymphocytes are important regulatory cells that secrete several cytokines and participate actively in this inflammatory response. According to the pattern of cytokines secreted, the immune response is classified as cytotoxic or type 1 [interferon (IFN)-gamma-, interleukin (IL)-2-dependent] and humoral or type 2 (IL-4-, IL-5-, IL-10- and IL-13-dependent). This paper sought to compare the intracellular profile of cytokine expression determined by flow cytometry in T lymphocytes harvested from bronchoalveolar lavage (BAL) and peripheral blood in patients with COPD, smokers with normal lung function and never smokers. We found that BAL T lymphocytes from COPD patients had a higher percentage of positive stained cells for most of the cytokines analysed when compared to never smokers or smokers with normal lung function. Differences reached statistical significance for IL-4, IL-10 and IL-13, particularly in CD8(+) T cells. Furthermore, the expression of most of these cytokines was related inversely to the degree of airflow obstruction present suggesting local activation and/or selective homing of T lymphocytes to the lungs in COPD patients. These observations were not reproduced in circulating T lymphocytes. These results suggest that BAL T lymphocytes in patients with COPD produce more cytokines than in controls and tend to show a type 2 pattern of intracellular cytokine expression, particularly a Tc-2 profile. This is related inversely to the degree of airflow obstruction present.

Decreased macrophage release of TGF-beta and TIMP-1 in chronic obstructive pulmonary disease

The present study tested the hypothesis that alveolar macrophages (AM) from patients with chronic obstructive pulmonary disease (COPD) release more pro-inflammatory and/or less anti-inflammatory mediators than those from smokers with normal lung function and never-smokers. AM were sorted by flow cytometry from bronchoalveolar lavage fluid in 13 patients with COPD (mean+/-SEM 67+/-2 yrs, forced expiratory volume in one second (FEV1) 61+/-4% reference), 16 smokers with normal lung function (55+/-2 yrs, FEV1 97+/-4% reference) and seven never-smokers (67+/-7 yrs, FEV1 94+/-4% reference). After sorting, AM were cultured (with and without lipopolysaccharide stimulation) after 4 h and 24 h, and the concentrations of leukotriene B4 (LTB4), transforming growth factor (TGF)-beta1 and tissue inhibitor of metalloproteinase (TIMP)-1 were quantified in the supernatant by ELISA. The production of reactive oxygen intermediates (ROI) in freshly isolated AM was determined by flow cytometry. LTB4 secretion and ROI production were not different between groups. In contrast, AM from COPD patients released significantly less TGF-beta1 and TIMP-1 than those from smokers with normal lung function and nonsmokers. In conclusion, these observations are compatible with reduced anti-inflammatory and anti-elastolytic capacity in chronic obstructive pulmonary disease, which is likely to contribute to the pathogenesis of the disease.

Blunted gamma delta T-lymphocyte response in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is characterised by an excessive inflammatory response to inhaled particles, mostly tobacco smoking. Although inflammation is present in all smokers, only a percentage of them develop COPD. T-lymphocytes are important effector and regulatory cells that participate actively in the inflammatory response of COPD. They comprise the T-cell receptor (TCR)-alpha beta (CD4+ and CD8+) and TCR-gamma delta T-lymphocytes. The latter represent a small percentage of the total T-cell population, but play a key role in tissue repair and mucosal homeostasis. To investigate TCR-alpha beta (CD4+ and CD8+) and TCR-gamma delta T-lymphocytes in COPD, the present authors determined, by flow cytometry, the distribution of both subpopulations in peripheral blood and bronchoalveolar lavage (BAL) samples obtained from patients with COPD, smokers with normal lung function and never-smokers. The present study found that: 1) the distribution of CD4+ and CD8+ lymphocytes in blood and BAL was similar in all three groups; 2) compared with nonsmokers, gamma delta T-lymphocytes were significantly increased in smokers with preserved lung function; and 3) this response was blunted in patients with COPD. These results highlight a novel, potentially relevant, pathogenic mechanism in chronic obstructive pulmonary disease.

[Comparison of the effectiveness of pentobarbital and thiopental in patients with refractory intracranial hypertension. Preliminary report of 20 patients]

OBJECTIVE

To assess the effectiveness of pentobarbital and thiopental to control raised intracranial pressure (ICP), refractory to first level measures, in patients with severe traumatic brain injury.

MATERIAL AND METHODS

Prospective, randomized study to compare the effectiveness between two treatments: pentobarbital and thiopental. The patients will be selected from those admitted to the Intensive Care Unit with a severe traumatic brain injury (postresuscitation Glasgow Coma Scale equal or less than 8 points) and raised ICP (ICP>20 mmHg) refractory to first level measures according to the Brain Trauma Foundation guidelines. The adverse effects of both treatments were also collected.

RESULTS

We present the results of the first 20 patients included. Ten received pentobarbital and the other ten thiopental. There were no statistically significance differences in patients'characteristics (age, sex, severity of the trauma at admission and comorbilities). There were no differences between both groups neither in the Glasgow Coma Scale at admission (thiopental six points; pentobarbital seven points; P=0.26) nor in the admission Cranial Tomography, according to the Traumatic Coma Data Bank Classification. Thiopental treatment controlled raised ICP in five cases and pentobarbital in two cases (P=0.16). Five patients in the thiopental group died and eight in the pentobarbital group (P=0.16). There were no statistically differences between both groups regarding to the presence of hypotension (P=1) or infectious complications.

CONCLUSIONS

These preliminary results indicate that thiopental could be more effective than pentobarbital in patients with refractory intracranial hypertension. These results support previous experimental findings that show that both treatments are not equal and justify to continue this study.

Experience in management of 51 non-functioning pituitary adenomas: indications for post-operative radiotherapy

OBJECT

The indications for additional radiotherapy (RT) after surgery for non-functioning pituitary adenoma are controversial. The goal of this retrospective study was to evaluate the outcome of surgically treated patients, with or without post- operative irradiation.

METHODS

Review of cases treated for non-functioning pituitary adenoma. Fifty-one patients were identified, with a mean post-operative follow-up of 6.4+/-3.5 yr. Twenty-nine patients showed residual tumor after surgery and 22 did not. Serial endocrine, visual and radiological evaluations were made after treatment to assess the efficacy and toxicity of surgery and RT. Twenty-seven patients with residual tumor after surgery received RT (22 of them during the post-operative period and 5 after an interval of several yr: 3 because of increased tumor size and 2 with stable residual lesion); tumors in 14 of these patients decreased in size, 11 appeared to be stable on imaging and one patient showed some increase in tumor size (one patient was not followed-up). The residual tumors of the 2 non-irradiated patients remained stable after 5 and 7 yr, respectively. Twenty-two patients without residual disease after surgery (11 with post-operative irradiation, 1 with RT 5 yr after transsphenoidal surgery because of tumor recurrence, and 10 without RT) have shown no evidence of tumor regrowth on serial images.

CONCLUSIONS

Radiotherapy can be avoided in patients with complete macroscopic resection and absence of residual tumor in post-operative images; they must be carefully followed using imaging techniques and, in the case of recurrence, they should be re-operated and/or irradiated.

Varying additive effects of bromocriptine with two somatostatin analogs in cultures of GH-secreting adenomas

In this study, we have investigated the effect of combined treatment using two somatostatin analogs, lanreotide or octreotide, with bromocriptine on GH release in cultures of GH-secreting pituitary tumors. Sixteen acromegalic patients were included in the study. All patients had been treated with lanreotide prior to the surgery. Five patients (31.2 %) reached GH levels below 2.0 microg/l and normal IGF-I levels according to age and sex after lanreotide treatment. A positive correlation was observed between the lanreotide-induced inhibition of GH release in vitro and serum GH decrease after lanreotide treatment (r = 0.52; p = 0.03). Combined treatment significantly inhibited GH release in vitro in 8 of the 16 tumors (50 %). However, only 5 (31.2 %) of the respective patients had been resistant to presurgical treatment with lanreotide. Three of these 5 patients (18.7 %) responded to a BC concentration similar to that achieved with therapeutic doses, and in 2 patients only when a pharmacological dose of BC was used in the combined treatment. The additive effect was observed with the combination of lanreotide and BC in 6 tumors and with octreotide and BC in 3. Only one tumor showed simultaneous response to both types of combination. These results suggest that the additive effect under the combined treatment might be found between 18 and 30 % of patients who are resistant to these drugs, and that different combinations of somatostatin analogs and dopamine agonists should be tested in resistant patients.

The complete normalization of the adrenocortical function as the criterion of cure after transsphenoidal surgery for Cushing's disease

Transsphenoidal microsurgery is the standard treatment for patients with Cushing's disease. However, there is general lack of agreement regarding the definition of cure. We studied 58 patients with corrected hypercortisolism after transsphenoidal surgery for Cushing's disease. Plasma and urinary cortisol levels were measured after surgery. After the postsurgical hypocortisolism stage (or periodically in patients without hypocortisolism), urinary free cortisol, plasma cortisol at 0800 h and 2300 h, morning cortisol after 1 mg dexamethasone, and cortisol response to insulin-induced hypoglycemia were performed. Patients were classified in 3 groups: group I, patients with transient hypocortisolism and normal hypothalamus-pituitary-adrenal axis afterwards; group II, patients with transient hypocortisolism and abnormalities in the circadian rhythm or the stress response afterwards; and group III, patients without postoperative hypocortisolism. Thirty-three patients were included in group I, 8 in group II, and 17 in group III. Groups I and II were similar in postsurgical plasma cortisol (46.9 +/- 30.3 vs. 60.7 +/- 38.6 nM) and mean follow-up (69.8 vs. 68.8 months) but were significantly different in their recurrence rate (3.4% vs. 50%, P < 0.001). Patients in group III had normal postsurgical plasma and urinary cortisol but persistent abnormalities in circadian rhythm and stress response. After a mean follow-up of 39.1 months, their recurrence rate was similar to that of group II (64.7% vs. 50%). The complete normalization of the adrenocortical function, which is always preceded by postsurgical hypocortisolism, is associated with a very low recurrence risk and should be considered, in our opinion, the main criterion of surgical cure in Cushing's disease.

Apparent cure of Graves-Basedow disease after sibling allogeneic bone marrow transplantation

Evidence that allogeneic bone marrow transplantation (BMT) can cure or alter the course of intractable autoimmune diseases comes from both extensive experimental work in animal models and anecdotal case reports in humans. We describe a female patient diagnosed as having severe aplastic anaemia (SAA), hyperthyroidism and ophthalmopathy of Graves-Basedow disease who received a BMT from her histocompatible sister. Fifty-three months after BMT, complete remission of hyperthyroidism and ocular signs persists. The SAA is cured and she is free of any chronic graft-versus-host disease (GVHD). In the early post-BMT period, PCR analysis of bone marrow and peripheral blood cells confirmed a complete chimerism of donor origin. Thus, it is plausible to attribute the resolution of the patient's thyroid hyperfunction and opththalmopathy to the replacement of the host immune system.

Growth hormone secretory response to intravenous galanin infusion in acromegalic patients

Galanin is a 29-amino acid neuropeptide which stimulates the secretion of growth hormone (GH) in normal men. Although the diagnosis of acromegaly involves demonstrating hypersecretion of GH and/or abnormalities in GH secretory dynamics, sometimes it is difficult to establish the activity of the disease. The aim of our study was to assess the response to galanin infusion in acromegalic patients (active and cured). We studied 19 subjects: 5 healthy volunteers (group I), 9 patients with active acromegaly (group II), and 5 with acromegaly cured after transsphenoidal surgery (group III). We performed a test of infusion with porcine galanin (8 microg/Kg/h) to study the secretory response of the GH. Galanin produced a marked increase in GH in the controls, group I (F9,36 = 5.34; p < 0.01) and in the cured patients, group III (F9,36 = 7.35; p < 0.01). On the other hand, galanin did not significantly modify the secretion of GH in the patients with active disease, group II. The areas under the curve (AUC) were higher in groups I and III compared to group II (p < 0.01). Nevertheless, there were no statistically significant differences in the AUC of groups I and III. Our results indicate that the differences in the GH response to galanin in patients with active and cured acromegaly could be of value in the study of the disease.

The long-term outcome of pituitary irradiation after unsuccessful transsphenoidal surgery in Cushing's disease

BACKGROUND

Irradiation of the pituitary is widely considered the most appropriate treatment for patients with Cushing's disease in whom transsphenoidal microsurgery has been unsuccessful. However, there is little information about the long-term efficacy of this treatment.

METHODS

We used external pituitary radiation to treat 30 adult patients with persistent or recurrent Cushing's disease after unsuccessful transsphenoidal surgery. The mean (+/-SD) dose of radiation was 50+/-1 Gy. Pituitary and adrenal function was assessed every six months after radiation therapy. Remission was defined as the regression of symptoms and signs of Cushing's syndrome, normal urinary cortisol excretion, and a low plasma cortisol concentration in the morning after the administration of 1 mg of dexamethasone at midnight.

RESULTS

Twenty-five patients (83 percent) had remissions during a median follow-up of 42 months (range, 18 to 114). The remissions began 6 to 60 months after radiation therapy, but in most cases (22 patients) remission occurred during the first 2 years. None of the 25 patients had a relapse of Cushing's disease after remission was achieved. There was no relation between the response to radiotherapy and sex, age, urinary cortisol excretion before radiotherapy, the interval between surgery and radiotherapy, whether a pituitary adenoma was found by pathological examination, or tumor size. Seventeen patients had a deficiency of growth hormone after radiation therapy, 10 had a deficiency of gonadotropins, 4 had a deficiency of thyrotropin, and 1 had a deficiency of corticotropin.

CONCLUSIONS

Pituitary irradiation is an effective and well-tolerated treatment for patients with Cushing's disease in whom transsphenoidal surgery is unsuccessful.

Cushing's syndrome due to autonomous macronodular adrenal hyperplasia: long-term follow-up after unilateral adrenalectomy

This report describes a case of Cushing's syndrome due to autonomous macronodular adrenocortical hyperplasia in which unilateral resection of the right adrenal resolved the Cushing's syndrome.

Petrosal sinus sampling for diagnosis of Cushing's disease: evidence of false negative results

OBJECTIVE

While inferior petrosal sinus (IPS) sampling correctly diagnoses pituitary-dependent Cushing's syndrome if a significant ratio of plasma ACTH between the IPS and the peripheral blood is demonstrated, little has been said about the significance of a negative ratio in Cushing's disease (e.g. a false-negative result). This study evaluates the results of IPS sampling in patients with Cushing's disease, and compares them with both imaging findings and transsphenoidal examination.

DESIGN

The results of IPS sampling were retrospectively compared with both imaging findings and transsphenoidal examination. IPS samples were obtained before and 2, 5 and 10 minutes after intravenous administration of 100 micrograms of CRH.

PATIENTS

Thirty-two patients with Cushing's disease were evaluated. All subsequently underwent transphenoidal examination of the pituitary gland.

MEASUREMENTS

The ratio of the ACTH concentrations at the IPS and in the peripheral blood (IPS:P ratio), and the ratio of the ACTH concentrations between the IPSs (interpetrosal ratio) were calculated. Radiographic evaluation of the pituitary gland was performed with magnetic resonance imaging (MRI, 29 cases) or computed tomography imaging (CT, 3 cases).

RESULTS

Transsphenoidal examination of the pituitary gland revealed a microadenoma in 27 cases. Radiological imaging showed a signal compatible with a microadenoma in 22 cases (68.8%), and correctly located the tumour at the side found at surgery in 14 of the 22 cases with positive transsphenoidal findings (MRI 13 cases, CT 1 case, overall 63.6%). Successful bilateral catheterization was accomplished in 30 patients (93.8%). Samples before and after CRH stimulation were drawn in 24 cases. No major complications were observed with the technique. IPS catheterization correctly predicted Cushing's disease (by means of a significant IPS: P ACTH ratio) in 27 of the 30 patients (90%) with basal sampling, and in 23 of the 24 cases with samples drawn before and after CRH administration (95.8%). Taking into account the 12 patients with a lateral microadenoma shown at transsphenoidal examination, IP sinus ACTH ratio was in agreement with the side recorded by the neurosurgeon in 8/12 cases (66.7%). MRI correctly located the tumour in 8/12 patients (66.7%). One patient showed no significant IPS: P ACTH ratio in any set of samples. His MRI showed no sign of a microadenoma. Two years later, another pituitary MRI evaluation showed a midline hypodense signal. The transsphenoidal examination revealed a microadenoma and the post-operative plasma cortisol and urinary free cortisol fell to 293 nmol/l and 100 nmol/24 h, respectively.

CONCLUSIONS

Only when a significant IPS:P ACTH ratio is present can Cushing's disease be established by IPS sampling. The absence of a significant IPS: P ACTH ratio does not necessarily imply ectopic secretion of ACTH, nor does it exclude Cushing's disease. The results of lateralization by IPS sampling do not remove the need for a thorough transsphenoidal examination of the contents of the sella turcica.

Serum growth hormone-binding protein is decreased in prepubertal children with idiopathic short stature

The causes for growth failure in children with idiopathic short stature (ISS) are not definitely established. Peripheral GH resistance due to changes at the level of the GH receptor has been suggested as one of the most probable explanation. In this study, we have selected a group of prepubertal children with ISS to evaluate the GHBP/receptor status by measuring the GH binding protein (GHBP) activity in plasma. Thirty prepubertal children with ISS (18 boys and 12 girls; age range: 4.79 to 11.33 yr) and twenty age-matched children with normal growth (11 boys and 9 girls) were studied. The ISS group presented growth retardation of -2.3 +/- 0.43 SD score (mean +/- SD) and normal GH secretion. Plasma IGF-I levels were below or in the low normal range (mean +/- SD: 136.3 +/- 62.3 micrograms/l, a concentration that was significantly different from IGF-I levels in the normal group (mean +/- SD: 187 +/- 57.5 micrograms/l p < 0.005). Plasma GHBP activity using a GH-binding/gel chromatography assay showed significantly lower values in ISS group (mean +/- SD: 7.17 +/- 1.5%) as compared with those of the control group (mean +/- SD: 12.02 +/- 2.04%; p < 0.001). There were no significant age- or sex-related differences in GHBP values in either group. The decreased GHBP levels observed in this group of children with ISS suggest that they may present a certain degree of GH insensitivity, probably due to a defect at the GH-receptor level.

Hypothalamic-pituitary dysfunction in patients with craniopharyngioma

OBJECTIVE

Previous studies of preoperative pituitary function in patients with craniopharyngioma have been limited in scope and have focused on children. We have evaluated the impact of craniopharyngiomas and their surgical treatment on pituitary function in a large group of mostly adult patients.

DESIGN

We performed a retrospective study of patients treated at our centre between 1980 and 1992.

PATIENTS

Twenty-two men and 13 women, most of them adults, treated surgically for craniopharyngioma during the above period.

MEASUREMENTS

Serum glucose, GH, LH, FSH, TSH and cortisol were measured both before and after a combined insulin induced hypoglycaemia, GnRH and TRH test. Basal concentrations of thyroid hormones, PRL and gonadal steroids were also measured. Preoperative computed tomographic scan was performed in all patients, and a detailed study of visual function before and after surgery was available for 32 of them. Endocrine function was reevaluated post-operatively.

RESULTS

In preoperative studies, 29 patients had some anterior pituitary deficit and 13 had diabetes insipidus. The most common abnormality was gonadotrophin deficiency, followed by GH deficiency. Dynamic studies suggested a hypothalamic origin for these deficits. In post-surgical evaluation, impaired pituitary function was observed in most patients. Panhypopituitarism was present in 28 cases and diabetes insipidus in 24.

CONCLUSIONS

Our report illustrates the high incidence of endocrine deficits in patients with craniopharyngioma. Additional hypothalamic-pituitary dysfunction usually occurs following surgical treatment of these tumours.

Treatment of invasive growth hormone pituitary adenomas with long-acting somatostatin analog SMS 201-995 before transsphenoidal surgery

The purpose of this study was to determine whether the long-acting somatostatin analog SMS 201-995 (octreotide) shrinks growth hormone (GH)-secreting adenomas and improves the results of subsequent transsphenoidal surgery. Ten previously untreated active acromegalic patients (nine women and one man) with invasive tumors were treated with SMS 201-995 (100 micrograms subcutaneously every 8 hours) for 6 weeks prior to transsphenoidal surgery. The clinical activity, mean GH secretion, insulin-like growth factor (IGF)-I concentration, and tumor volume were measured under basal conditions and on Days 14, 28, and 42 of treatment. The SMS 201-995 improved the symptoms of acromegaly in all patients. Mean levels of both GH and IGF-I (+/- standard deviation) were significantly decreased by Day 14 (from 92.9 +/- 30.5 to 44.9 +/- 20.3 micrograms/liter and from 10.6 +/- 7.4 to 5.9 +/- 2.6 U/ml, respectively), after which there were only slight further decreases. Six (60%) of the 10 patients experienced tumor shrinkage ranging from 9% to 78% (mean 30%). When it occurred, tumor shrinkage was significant by Day 14 (7.9 +/- 6.3 to 6.5 +/- 5.1 cu cm) and no further shrinkage was achieved by longer administration. Transsphenoidal surgery reduced postoperative GH levels to less than 2 micrograms/liter and IGF-I to less than 1.5 U/ml in six patients (60%). This percentage of cure is higher than expected from the literature and the authors' previous experience. However, an investigation of the influence of this drug on several parameters, such as reduction of tumor size or GH and IGF-I concentrations, has failed to prove any relationship. Only pretreatment size of the tumor was of predictive value with respect to the surgical outcome.

[A malignant extra-adrenal pheochromocytoma. Apropos 2 cases]

We present the case of two patients with extra-adrenal pheochromocytoma (left and right para-aorta abdominal) in which the pre-surgery search with metaiodobenzylguanidine-I-123 (MIBG-I-123) showed the existence of bone metastasis in skullcap, not previously suspected. In both patients a total resection of tumor was performed together with the bone lesions. These two cases confirm the great usefulness of MIBG-I-123 in the localization of metastasis in patients with malignant pheochromocytoma. At the same time we think that the resection of whole tumoral tissue through surgery is an adequate treatment when dealing with pheochromocytoma with isolated metastasis.

Results of external pituitary irradiation after unsuccessful transsphenoidal surgery in Cushing's disease

Fourteen adult patients (10 females and 4 males; age range 20-60 years) with persistent Cushing's disease after transsphenoidal microsurgery were treated with pituitary irradiation. Supervoltage multiportal administration was employed at a total dose of 50 Gy (+/- 0.65 SD). The interval between microsurgery and pituitary irradiation was less than 6 months in 6 patients and more than 6 months in 8. The pituitary-adrenal axis was evaluated postsurgically, before irradiation and every 6 months thereafter. The remaining anterior pituitary function was simultaneously tested. Remission rates at 12 months and 24 months after radiotherapy were 61 and 70%, respectively. Two patients developed TSH deficiency and another gonadotropin deficiency during the follow-up after radiation. We conclude that pituitary irradiation is the treatment of choice for persistent Cushing's disease after unsuccessful surgery because of its high efficiency and low incidence of adverse reactions when compared with other forms of treatment.

Increased insulin receptor binding in erythrocytes from growth hormone-deficient children

Erythrocytes from growth hormone-deficient children (GHd-children) (n = 10) showed a statistically significant increase in insulin binding at low unlabeled insulin concentrations, together with a threefold decrease in apparent receptor affinity, as compared to control children (C) (n = 11). Scatchard analysis of the binding data using the two-site model revealed that both the receptor concentration R1 [GHd-children 0.10 +/- 0.01 ng/ml and C 0.03 +/- 0.002 ng/ml] and the dissociation constant KD1 [GHd-children (0.48 +/- 0.05) x 10(-9) M and C (0.19 +/- 0.01) x 10(-9) M] for high affinity-low capacity sites were significantly increased in erythrocytes from GHd-children, while neither receptor concentrations (R2) nor the dissociation constant (KD2) for low affinity-high capacity sites proved to be altered. These events were accompanied by a normal sensitivity to insulin as well as glucose tolerance in the GHd-group. The meaning of the increased insulin binding with normal insulin sensitivity in GH-deficiency is discussed.

[Treatment of solitary toxic thyroid nodule with 131I: results in 43 patients]

BACKGROUND

Evaluation of the therapy with high-dose 131I in solitary toxic thyroid adenoma, with particular attention to the effects on thyroid function and on the nodular size.

METHODS

A retrospective study of 43 patients with solitary thyroid nodule treated with radioactive iodine (mean dose 26.6 mCi, range 10-35) and followed up for 49.7 +/- 36.6 months (range 6-186) with periodical clinical, laboratory and echographic evaluations.

RESULTS

Thirty-two patients (74.4%) had a normal thyroid function during follow-up. Five (11.6%) remained with hyperthyroidism and in 6 (13.9%) hypothyroidism developed 6-30 months after the administration of radioactive iodine. Three of these 6 had subclinical hypothyroidism, with mild increases in serum thyrotropin (TSH). Neither the development of hypothyroidism nor its persistence were significantly correlated with the initial thyroxin (T4) or triiodothyronine (T3) levels, the nodular size, the 131I dose, the incomplete inhibition of the extranodular thyroid parenchyma or the previous therapy with antithyroid drugs. The nodule diminished in size in 15 cases (38.4%), it disappeared in 9 (23%), it remained unchanged in 12 (30.7%) and it increased in 3 (7.7%).

CONCLUSIONS

The treatment of the solitary toxic thyroid nodule with relatively high 131I doses is a safe and effective procedure, with a prevalence of residual hypothyroidism which is lower than previously reported. The disappearance of the nodule was only achieved in a minority of cases.