PAI-BEL: a Belgian multicentre survey of primary adrenal insufficiency.

Objective: Primary adrenal insufficiency (PAI) is a rare disease with an increasing prevalence, which may be complicated by life-threatening adrenal crisis (AC). Good quality epidemiological data remain scarce. We performed a Belgian survey to describe the aetiology, clinical characteristics, treatment regimens, comorbidities and frequency of AC in PAI. Methods: A nationwide multicentre study involving 10 major university hospitals in Belgium collected data from adult patients with known PAI. Results: Two hundred patients were included in this survey. The median age at diagnosis was 38 years (IQR 25-48) with a higher female prevalence (F/M sex ratio = 1.53). The median disease duration was 13 years (IQR 7-25). Autoimmune disease was the most common aetiology (62.5%) followed by bilateral adrenalectomy (23.5%) and genetic variations (8.5%). The majority (96%) of patients were treated with hydrocortisone at a mean daily dose of 24.5 ± 7.0 mg, whereas 87.5% of patients also received fludrocortisone. About one-third of patients experienced one or more AC over the follow-up period, giving an incidence of 3.2 crises per 100 patient-years. There was no association between the incidence of AC and the maintenance dose of hydrocortisone. As high as 27.5% of patients were hypertensive, 17.5% had diabetes and 17.5% had a diagnosis of osteoporosis. Conclusion: This study provides the first information on the management of PAI in large clinical centres in Belgium, showing an increased frequency of postsurgical PAI, a nearly normal prevalence of several comorbidities and an overall good quality of care with a low incidence of adrenal crises, compared with data from other registries.

Two-day low-dose dexamethasone suppression test more accurate than overnight 1-mg in women taking oral contraceptives.

INTRODUCTION: Late-night salivary cortisol (LSaC) and 24-h urinary free cortisol measurement, and overnight 1-mg dexamethasone suppression test (1 mg-DST) are the first-line screening tests recommended for Cushing's syndrome. Through elevations in the level of cortisol-binding globulin, oral contraceptive agents lead to increases in the total plasma cortisol concentration, yielding false-positive 1 mg-DST results. OBJECTIVE: To compare the accuracy of the overnight 1-mg DST and two-day low-dose DST (2d-DST) in female volunteers taking combined oestrogen-progestin oral contraceptives (COCs). METHODS: This prospective study enrolled 30 healthy participants. Their plasma cortisol response levels were compared after the 1-mg DST and 2d-DST and classified into three categories: normal (≤50 nmol/L), doubtful (51-138 nmol/L) and abnormal (>138 nmol/L). Salivary cortisol was also measured at late night and after the DSTs. RESULTS: Following the 1-mg DST and 2d-DST, the plasma cortisol concentrations decreased to a median of 69 nmol/L and 37 nmol/L, respectively (p < 0.001). A statistically significant higher proportion of unclear or abnormal results were observed after the 1-mg DST (63%) than after the 2d-DST (27%) (p = 0.004). None of the values were >138 nmol/L after the 2d-DST, while 11% of them were abnormal after the 1-mg DST (p = 0.25). No LSaC value was abnormal. CONCLUSION: Our results suggest that, when late-night salivary cortisol is not available, the 2d-DST could be a better screening option than the 1-mg DST for women taking oral contraceptive agents who are reluctant to stop them. This finding requires confirmation in those with a suspicion of hypercortisolism.

Adrenal ganglioneuromas: a retrospective multicentric study of 104 cases from the COMETE network.

OBJECTIVE: Adrenal ganglioneuromas are rare, differentiated, neuroblastic tumors that originate from the peripheral sympathetic nervous system. Because of their rarity, information is limited, derived from small cases series. Our objective was to characterize this tumor and provide help for its management. METHODS: A retrospective multicenter analysis of adrenal ganglioneuromas from 20 French centers belonging to the COMETE network and one Belgian center. RESULTS: Among the 104 cases identified, 59.6% were women (n = 62/104), median age at diagnosis was 29 years, with 24 pediatric cases. 60.6% (n = 63/104) were incidentalomas. Ganglioneuromas were non-secreting tumors in 90.8% of cases (n = 89/98), whereas the preoperative hormonal evaluation was indeterminate for 9.2% of patients (n = 9/98). CT imaging, performed on 96 patients, revealed large tumors (median diameter of 50 mm) with a non-contrast density > 10 Hounsfield units in 98.1% (n = 52/53) and calcifications in 64.6% of cases (n = 31/48). Increased uptake on 123I-MIBG scintigraphy and 18F-FDG-PET/CT was observed in 26.7% (n = 8/30) and 42.2% (n = 19/45) of the tumors, respectively. All 104 patients underwent surgery. No recurrence was observed among the 42 patients who had an imaging follow-up (mean 29.6 months, median 18 months (4-156)). CONCLUSION: Adrenal ganglioneuromas are large tumors, mostly nonfunctioning, without benign imaging features. Although the duration of follow-up was limited in our series, no recurrence was identified. A review of the literature confirms the absence of postoperative recurrence. Based on all available data, in the absence of special circumstances (genetic form, uncertain histological diagnosis), long-term follow-up is not necessary after complete surgery for patients with an adrenal ganglioneuroma.

Etomidate infusion at low doses is an effective and safe treatment for severe Cushing's syndrome outside intensive care.

INTRODUCTION: Intravenous etomidate infusion is effective to rapidly lower cortisol levels in severe Cushing's syndrome (CS) in the intensive care unit (ICU). Recently, etomidate treatment has also been proposed at lower doses in non-ICU wards, but it is not yet clear how this approach compares to ICU treatment. METHODS: We compared data from patients with severe CS treated with high starting doses of etomidate (median: 0.30 mg/kg BW/day) in ICU or with lower starting doses (median: 0.025 mg/kg BW/day) in non-ICU medical wards. RESULTS: Fourteen patients were included, among which ten were treated with low starting doses (LD) and four with high starting doses etomidate (HD). All patients had severe and complicated CS related to adrenal carcinoma (n = 8) or ectopic ACTH secretion (n = 6). Etomidate was effective in reducing cortisol levels below 500 nmol/L in a median of 1 day in the HD group compared to 3 days in the LD group (P = 0.013). However, all patients of the HD group had etomidate-induced cortisol insufficiency and needed frequent monitoring, while no patient from the LD group required hydrocortisone supplementation. No patient in either group died from complications of CS or etomidate treatment, but final outcome was poor as six patients in the LD group and all four patients in the HD group died from their cancer during follow-up. CONCLUSION: Our study suggests that, for patients with severe CS who do not require intensive organ-supporting therapy, the use of very low doses of etomidate in medical wards should be considered.

Factors contributing to the resistance of the thyrocyte to hydrogen peroxide.

We studied the mechanism that may explain the relative resistance of thyrocytes to H2O2 compared to other cell types. Ability to degrade H2O2, glutathione peroxidase (GPx) activity, heme oxygenase-1 (HO-1) expression, cell survival and capacity to repair DNA damage after H2O2 exposure or irradiation were measured in human thyrocytes in primary culture and compared to the values obtained in human T-cells and different cell lines. Compared to other cell types, thyrocytes presented a low mortality rate after H2O2 exposure, rapidly degraded extracellular H2O2 and presented a high basal seleno-dependent GPx activity. Only in thyrocytes, H2O2 up-regulated GPx activity and expression of HO-1 mRNA. These effects were not reproduced by irradiation. DNA damage caused by H2O2 was more slowly repaired than that caused by irradiation and not repaired at all in T-cells. Our study demonstrates that the thyrocyte has specific protective mechanisms against H2O2 and its mutagenic effects.

Unilateral Adrenalectomy Could Be a Valid Option for Primary Nodular Adrenal Disease: Evidence From Twins.

Primary pigmented nodular adrenal disease (PPNAD) accounts for <1% of ACTH-independent Cushing syndrome. We describe the case of twin female patients with PPNAD who both had sustainable disease control after unilateral adrenalectomy, which corroborates current evidence in favor of unilateral adrenalectomy for a subset of patients with PPNAD. Patient A presented with a 10-kg weight gain over the past year and facial plethora. Diagnostic evaluation revealed abolition of normal cortisol rhythm with suppressed ACTH levels, normal adrenal CT and MRI imaging and a slightly left-predominant adrenal uptake on 131I iodomethyl norcholesterol scintigraphy coupled with single-photon emission CT/CT. PPNAD was confirmed after genetic testing revealed a known pathogenic PRKA1A mutation (c.709 (-7-2) del6). At that time, her twin sister (patient B) was asymptomatic. Patient A underwent successful unilateral adrenalectomy and histology confirmed PPNAD. Two years after initial onset of symptoms in patient A, patient B was seen for the same subtle symptoms of progressive weight gain. Diagnostic test results were identical, revealing the same clinical features and mutational status as patient A. Patient B also underwent unilateral adrenalectomy with a favorable outcome. Follow-up 3 years after surgery for patient A and 18 months for patient B showed sustained disease control without recurrence and uncompromised quality of life, with no adrenal insufficiency having occurred. Unilateral adrenalectomy can be a successful therapeutic approach for patients with PPNAD with a mild phenotype without the risk and the inconvenience of subsequent adrenal insufficiency, which alters quality of life.

Comparative analysis of the thyrocytes and T cells: responses to H2O2 and radiation reveals an H2O2-induced antioxidant transcriptional program in thyrocytes.

CONTEXT: Radiation is an established cause of thyroid cancer, and growing evidence supports a role for hydrogen peroxide (H2O2) in spontaneous thyroid carcinogenesis. Little is known about the molecular programs activated by these agents in thyrocytes. OBJECTIVE: The purpose of this study was to compare the responses of thyrocytes and T cells to H2O2 and radiation. METHODS: We profiled the DNA damage and cell death induced by γ-radiation (0.1-5 Gy) and H2O2 (0.0025-0.3 mM) in primary human thyrocytes and T cells. We next prepared thyroid and T-cell primary cultures from 8 donors operated for noncancerous thyroid pathological conditions and profiled their genome-wide transcriptional response 4 hours after (1) exposure to 1-Gy radiation, (2) treatment with H2O2 and (3) no treatment. Two H2O2 concentrations were investigated, calibrated in each cell type to elicit levels of single- and double-strand breaks equivalent to 1-Gy γ-radiation. RESULTS: Although thyrocytes and T cells had comparable radiation responses, 3- to 10-fold more H2O2 was needed to induce detectable DNA damage in thyrocytes. At H2O2 and radiation doses inducing double-strand breaks, cell death occurred after 24 hours in T cells but not in thyrocytes. The transcriptional responses of thyrocytes and T cells to radiation were similar, involving DNA repair and cell death genes. In addition to this transcriptional program, H2O2 also up-regulated antioxidant genes in thyrocytes, including glutathione peroxidases and heme oxygenase at the double-strand breaks-inducing concentration. In contrast, a transcriptional storm involving thousands of genes was raised in T cells. Finally, we showed that inhibiting glutathione peroxidases activity increased the DNA damaging effect of H2O2 in thyrocytes. CONCLUSION: We propose that high H2O2 production in thyrocytes is matched with specific transcriptionally regulated antioxidant protection.

Hydrogen peroxide induces DNA single- and double-strand breaks in thyroid cells and is therefore a potential mutagen for this organ.

DNA double-strand breaks (DSBs) are considered as one of the primary causes of cancer but their induction by hydrogen peroxide (H(2)O(2)) is still controversial. In this work, we studied whether the high levels of H(2)O(2) produced in the thyroid to oxidize iodide could induce DNA modifications. Scores of DNA damage, in terms of strand breaks, were obtained by comet assay (alkaline condition for single-strand breaks (SSBs) and neutral condition for DSBs). We demonstrated that in a rat thyroid cell line (PCCl3), non-lethal concentrations of H(2)O(2) (0.1-0.5 mmol/l) as well as irradiation (1-10 Gy) provoked a large number of SSBs ( approximately 2-3 times control DNA damage values) but also high levels of DSBs (1.2-2.3 times control DNA damage values). We confirmed the generation of DSBs in this cell line and also in human thyroid in primary culture and in pig thyroid slices by measuring phosphorylation of histone H2AX. L-Buthionine-sulfoximine, an agent that depletes cells of glutathione, decreased the threshold to observe H(2)O(2)-induced DNA damage. Moreover, we showed that DNA breaks induced by H(2)O(2) were more slowly repaired than those induced by irradiation. In conclusion, H(2)O(2) causes SSBs and DSBs in thyroid cells. DSBs are produced in amounts comparable with those observed after irradiation but with a slower repair. These data support the hypothesis that the generation of H(2)O(2) in thyroid could also play a role in mutagenesis particularly in the case of antioxidant defense deficiency.

Gene expression in RET/PTC3 and E7 transgenic mouse thyroids: RET/PTC3 but not E7 tumors are partial and transient models of human papillary thyroid cancers.

We studied gene expression profiles in two mouse models of human thyroid carcinoma: the Tg-RET/PTC3 (RP3) and Tg-E7 mice. RP3 fusion gene is the most frequent mutation found in the first wave post-Chernobyl papillary thyroid cancers (PTCs). E7 is an oncoprotein derived from the human papillomavirus 16 responsible for most cervical carcinoma in women. Both transgenic mice develop thyroid hyperplasia followed by solid differentiated carcinoma in older animals. To understand the different steps leading to carcinoma, we analyzed thyroid gene expression in both strains at different ages by microarray technology. Important biological processes were differentially regulated in the two tumor types. In E7 thyroids, cell cycle was the most up-regulated process, an observation consistent with the huge size of these tumors. In RP3 thyroids, contrary to E7 tumors, several human PTC characteristics were observed: overexpression of many immune-related genes, regulation of human PTC markers, up-regulation of EGF-like growth factors and significant regulation of angiogenesis and extracellular matrix remodeling-related genes. However, similarities were incomplete; they did not concern the overall gene expression and were not conserved in old animals. Therefore, RP3 tumors are partial and transient models of human PTC. They constitute a good model, especially in young animals, to study the respective role of the biological processes shared with human PTC and will allow testing drugs targeting these validated variables.