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Parathyroid Apoplexy Following Cinacalcet Treatment in Primary Hyperparathyroidism
Full text linkCinacalcet, a calcimimetic drug, is considered a safe and valid option for the treatment of hypercalcemia in patients with primary hyperparathyroidism who are unable to undergo parathyroidectomy. Hypocalcemia and gastrointestinal adverse reactions are the main side effects reported in patients treated with cinacalcet. We present here the case of an 80-years-old patient with primary hyperparathyroidism treated with cinacalcet for 17 months who developed a severe and symptomatic episode of hypocalcemia requiring hospitalization 1 month after reaching a daily dose of 180 mg. Follow-up laboratory and imaging exams showed remission of primary hyperparathyroidism and disappearance of the parathyroid adenoma, suggesting a possible association between cinacalcet therapy and parathyroid infarction resulting in normalization of the elevated serum parathyroid hormone levels and severe hypocalcemia. No known cases of iatrogenic parathyroid apoplexy have thus far been described. We report here the first case of parathyroid apoplexy associated with the administration of cinacalcet in a patient with primary hyperparathyroidism. Parathyroid apoplexy features heterogeneous clinical manifestations ranging from relatively asymptomatic to potentially life-threatening cases. The occurrence of this complication should be carefully considered in patients with primary hyperparathyroidism in therapy with cinacalcet
MON-450 Pituitary Antibodies In A Cohort Of Us Service Members With Traumatic Brain Injury
No full textTraumatic brain injury (TBI) causes pituitary dysfunction, mainly featuring GH deficiency. Several mechanisms have been proposed to explain this post-traumatic dyspituitarism, including autoimmunity. We analyzed pituitary antibodies in 100 of US Service Members chosen for a history of TBI and hearing impairment, a concurrence typically seen after blast injuries. Each soldier provided two sera, one before (-1,765 to - 66 days) and one after (10 to 177 days) TBI. All 200 sera were screened by indirect immunofluorescence for binding to a human pituitary gland collected at autopsy. Positive sera were then tested by double indirect immunofluorescence for recognition of cells expressing GH, PRL, ACTH, LH, FSH, TSH, alpha-internexin (INA), vimentin, or glial fibrillary-acidic protein (GFAP). Sera were also tested by ELISA for recognition of native GH or recombinant INA. 63 of 200 sera (31 %) contained pituitary antibodies: of them, 33 (16%) recognized the adenohypophysis, 18 (9 %) the neurohypophysis, and 12 (6%) both lobes. In the adenohypophysis, TSH-secreting cells were the most common target (26 of 45, 58%), followed by INA expressing cells (17 of 45, 37%). In the neurohypophysis, 20 of 30 sera (67 %) recognized INA, 6 (20%) vimentin, and 4 (13%) GFAP-expressing cells. There was no temporal association between pituitary antibodies and TBI: of the sera recognizing TSH-secreting cells, half had antibodies in both the pre- and post-TBI serum (13 of 26, 50%), a quarter (6 of 26, 23%) in the pre-TBI serum, and a quarter (7 of 26, 27%) in the post-TBI serum. Similarly, of the sera recognizing INA-expressing cells, 2 (11.7%) had antibodies in both the pre- and post-TBI serum, 9 (53%) only in the pre-TBI serum, and 6 (35.2%) only in the post-TBI serum. INA antibodies measured by ELISA did not differ between the pre- and post-TBI time points. On the contrary, GH antibodies tended to increase after TBI, although not reaching statistical significance (p= 0.055). The study highlights a preferential recognition of TSH- and INA-expressing cells in TBI patients, which remains to be interpreted in the context of their endocrine dysfunctions. It also suggests that the appearance of GH antibodies after TBI contributes to the GH deficiency typically seen in these patients
Thyroid Autoimmunity in Female Infertility and Assisted Reproductive Technology Outcome
Full text linkThe regulation of the female reproductive system is one of the most relevant actions of thyroid hormones. Adequate thyroid hormones production is essential for normal menstrual function and fertility as well as for the successful maintenance of pregnancy. The relationship between reproductive failure and thyroid disorders is particularly relevant and attracts attention worldwide. Thyroid autoimmunity (TAI), defined by the presence of circulating antithyroid antibodies targeting thyroid peroxidase (TPOAb) and thyroglobulin (TgAb), is prevalent among women of reproductive age and is the most frequent cause of thyroid dysfunction. Several studies addressed the association between TAI, thyroid function, and fertility as well as pregnancy outcome after spontaneous or assisted conception. Infertility, miscarriages, and fetal-maternal complications are described in overt autoimmune hypothyroidism. More debatable is the role of mild thyroid dysfunction, mainly subclinical hypothyroidism (SCH), and TAI in the absence of thyroid dysfunction in infertility and reproductive outcome. Assisted reproductive technology (ART) has become an integral element of care for infertility. Women with TAI undergoing ART are of particular interest since they carry a higher risk of developing hypothyroidism after the ovarian stimulation but whether TAI, in absence of thyroid dysfunction, adversely affects ART outcome is still controversial. Likewise, the role of levothyroxine (LT4) in improving fertility and the success of ART in euthyroid women with TAI is unclear. This review discusses the role of TAI, in the absence of thyroid dysfunction, in infertility and in ART outcome
Pre-existing Thyroiditis Ameliorates Papillary Thyroid Cancer: Insights From a New Mouse Model
No full textPapillary thyroid cancer (PTC) often co-occurs with Hashimoto’s thyroiditis, an association that has long been reported in clinical studies yet remains controversial. Some studies, in fact, have suggested a protective effect of thyroiditis while others have not. We generated a mouse model where PTC and thyroiditis develop in a predictable manner, combining the oncogenic drive of the BRAF(v600E) mutation (inducible by tamoxifen) to the thyroiditis susceptibility of the NOD.H2(h4) strain (inducible by iodine). A total of 113 NOD.H2(h4)_TPO-CRE-ER_BRAF(V600E) mice (50 followed throughout lifetime and 63 sacrificed at 16 weeks post tamoxifen) were used to determine whether the PTC phenotype differs when thyroiditis precedes or coincides with the onset of PTC. Mice with pre-existing thyroiditis lived longer (median survival of 28.2 weeks post tamoxifen) than those with concomitant (25.6 weeks) or no (24.5 weeks) thyroiditis (P < 0.01 by Laplace regression). PTC developed less frequently (33%) in the pre-existing thyroiditis group than the concomitant (100%) or no (100%) thyroiditis groups (P < 0.001 by chi-squared) and showed less aggressive histopathological features. The intratumoral mononuclear cell infiltration was more prominent in mice with pre-existing thyroiditis (P = 0.002 vs the other groups) and sustained by a significant expansion of effector memory CD8 + T cells and CD19 + B cells. These findings shed light on the controversial PTC-thyroiditis association and emphasize the contribution of intratumoral T and B lymphocytes to the evolution of PTC
Hypophysitis Secondary to Cytotoxic T-Lymphocyte-Associated Protein 4 Blockade: Insights into Pathogenesis from an Autopsy Series
No full textHypophysitis that develops in cancer patients treated with monoclonal antibodies blocking cytotoxic T-lymphocyte-associated protein 4 (CTLA-4; an inhibitory molecule classically expressed on T cells) is now reported at an incidence of approximately 10%. Its pathogenesis is unknown, in part because no pathological examination of the pituitary gland has been reported to date. We analyzed at autopsy the pituitary glands of six cancer patients treated with CTLA-4 blockade, one with clinical and pathological evidence of hypophysitis, one with mild lymphocytic infiltration in the pituitary gland but no clinical signs of hypophysitis, and four with normal pituitary structure and function. CTLA-4 antigen was expressed by pituitary endocrine cells in all patients but at different levels. The highest levels were found in the patient who had clinical and pathological evidence of severe hypophysitis. This high pituitary CTLA-4 expression was associated with T-cell infiltration and IgG-dependent complement fixation and phagocytosis, immune reactions that induced an extensive destruction of the adenohypophyseal architecture. Pituitary CTLA-4 expression was confirmed in a validation group of 37 surgical pituitary adenomas and 11 normal pituitary glands. The study suggests that administration of CTLA-4 blocking antibodies to patients who express high levels of CTLA-4 antigen in the pituitary can cause an aggressive (necrotizing) form of hypophysitis through type IV (T-cell dependent) and type II (IgG dependent) immune mechanisms
A subset of men with age-related decline in testosterone have gonadotroph autoantibodies
No full textContext: Age-related decline in serum testosterone (T) is being increasingly diagnosed. In most men, it associates with low or inappropriately normal gonadotropin levels, which suggests a hypothalamic-pituitary etiology. Autoantibodies against adenohypophyseal cells have been associated with pituitary dysfunction; however, the prevalence of pituitary autoimmunity in this age-related T decline has not been assessed. Objectives: This is a proof-of-concept study with the objective of determining the prevalence of antibodies to gonadotrophs in older men with age-related low T and compare it with healthy young and older eugonadal men. Study Design: This is a cross-sectional case-control study of 182 men. Cases included 100 older men (≥65 years) with age-related low T levels; the control groups were composed of 50 young and 32 older healthy eugonadal men. Serum antibodies against the anterior pituitary gland were measured using a two-step approach: 1) single indirect immunofluorescence (ie, participant serum only) to determine the pattern of cytosolic staining; and 2) double indirect immunofluorescence (ie, participant serum plus a commercial adenohypophyseal hormone antibody) to identify the anterior pituitary cell type recognized by the patient's antibodies). Results: In participants with positive antipituitary antibodies, the granular cytosolic pattern (highly predictive of pituitary autoimmunity) was only seen in older men with age-related low T (4%) and none in control groups (0%, P = .001). Double indirect immunofluorescence confirmed that pituitary antibodies were exclusively directed against the gonadotrophs. Conclusion: A subset of older men with age-related low T levels have specific antibodies against the gonadotrophs. Whether these antibodies are pathogenic and contributory to the age-related decline in T remains to be established
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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