Tumour-Induced Osteomalacia-A Long Way to the Diagnosis Facilitated by [68Ga]Ga-DOTATATE PET/CT.

Background: Tumour-induced osteomalacia (TIO) is a rare paraneoplastic syndrome. Detecting the primary tumour in TIO is challenging using conventional imaging methods. This study assesses the efficacy of [68Ga]Ga-DOTATATE PET/CT in identifying the primary tumour. Methods: Six patients with suspected TIO underwent [68Ga]Ga-DOTATATE PET/CT. The patients' clinical history and biochemical parameters were analysed. Results: [68Ga]Ga-DOTATATE PET/CT successfully identified primary tumours in four patients (femoral bones for two, iliac bone for one, subcutaneous tissue of pubic region for one). Tumour removal led to clinical and laboratory improvement. In one patient, PET/CT showed rib uptake, but the biopsy was negative. One patient showed no tumour lesions on PET/CT despite clinical evidence. Two patients had focal recurrence at the primary tumour site, detected by follow-up PET/CT. Conclusions: [68Ga]Ga-DOTATATE PET/CT is a valuable tool for detecting primary tumours in TIO, aiding in accurate diagnosis and guiding surgery, leading to improved outcomes. Further research is needed to validate these findings and explore [68Ga]Ga-DOTATATE PET/CT in other paraneoplastic syndromes.

Resistance to thyroid hormone due to a novel mutation in the thyroid beta receptor (THRß) gene coexisting with autoimmune thyroid disease-A case report.

Resistance to thyroid hormone (RTH) is a syndrome characterized by impaired responsiveness of target tissues to thyroid hormones. The relationship between RTHß and thyroid autoimmunity has been under research. In this study, we demonstrate a case report of a woman with a novel mutation in THRß gene coexisting with autoimmune thyroid disease (AITD). The 36-year-old woman has been treated since childhood for a thyroid disease. Based on high levels of thyroid hormones (THs) and elevated concentrations of thyroperoxidase and thyroglobulin antibodies (TPOAb and TgAb, respectively), she received unnecessary long-term treatment with methimazole and finally underwent subtotal thyroidectomy. After the surgery, her TSH level remained significantly elevated, despite the treatment with 150 + 15 µg of thyroxine and triiodothyronine. A sequence analysis of the THRß gene revealed a novel dinucleotide substitution affecting codon 453, resulting in the replacement of the normal proline with an asparagine (c.1357_1358delinsAA, p.(Pro453Asn)). The mutation has not been described in the literature yet; however, THRß codon 453 represents a mutational hot spot, frequently altered in the TH receptor ß gene. After establishing the diagnosis of RTH, the patient was treated with 300 µg of thyroxine, which showed clinical improvement and normalization of TSH. The coexistence of RTHß and AITD may additionally impede establishment of a proper diagnosis, leading to unnecessary therapy and delayed correct treatment. The presented case encourages a closer cooperation between clinical endocrinologists and geneticists.

Frequency of COVID-19 Infection as a Function of Vitamin D Levels.

BACKGROUND: It has been speculated that higher concentrations of 25-hydroxy-vitamin D (25OHD) provide some protection against COVID-19. We assessed whether there is any relationship between 25OHD concentrations and the subsequent development of COVID-19 infection. MATERIALS AND METHODS: Concentrations of 25OHD were measured in March-April 2020 in 134 healthy subjects (57 males), age range 6-50, from a single urban general practice in central Poland. Data on COVID-19 infection during the subsequent 12 months (prior to the vaccination program) were obtained from the national database of COVID-19 cases. None of the subjects received any 25OHD supplements. RESULTS: The average 25OHD concentrations were 18.1 ± 7.39 ng/mL (37.3% had 25OHD above 20 ng/mL). Thirty-one (23.1%) patients developed COVID-19 infection, but an increased risk was only observed in individuals with 25OHD concentrations below 12 ng/mL (COVID-19 infection in 11 out of 25 patients (44%) with 25OHD < 12 ng/mL versus 20 out of 109 (18.3%) for those with 25OHD above 12 ng/mL, p = 0.0063). Such a relationship was no longer observed for subjects with 25OHD concentrations above 20 ng/mL (p = 0.2787). CONCLUSIONS: Although only a minority of healthy subjects had 25OHD concentrations above 20 ng/mL in spring, an increased risk of subsequent COVID-19 infection was only observed in those with severe 25OHD deficiency (<12 ng/mL).

The effects of season (spring versus autumn) on diagnosis of normocalcemic primary hyperparathyroidism.

Background: Raised parathormone (PTH) and normal calcium concentrations can be observed both in normocalcemic primary hyperparathyroidism (nPHPT) and in secondary hyperparathyroidism, e.g. due to vitamin D deficiency. We assessed the impact of season on the validity of diagnosis of nPHPT in terms of screening investigations to be performed in the primary care settings. Material and methods: On two occasions (March/April & September/October) we measured vitamin D (25OHD), PTH and total calcium in 125 healthy subjects, age range 6-50, not taking any vitamin D supplements. Results: In autumn there was an increase in 25OHD concentrations (from 18.1 ± 7.37ng/ml to 24.58 ± 7.72ng/ml, p<0.0001), a decline in PTH from 44.40 ± 17.76pg/ml to 36.63 ± 14.84pg/ml, p<0.001), without change in calcium levels. Only 45 subjects (36%) were vitamin D sufficient (25OHD>20/ml) in spring versus 83 (66.4%) in autumn, p<0.001. Elevated PTH concentrations were noted in 10 subjects in spring (8%) and in six subjects (4.8%) (p<0.05) in autumn. In spring, however, eight out of ten of these subjects (80%) had 25OHD<20 ng/ml, versus one in six (16.7%) in autumn (p<0.01). Normalization of PTH was observed in seven out ten subjects (70%), and all of them had 25-OHD<20 ng/ml in spring. Conclusions: In spring elevated PTH concentrations in the setting of normocalcemia are more likely to be caused by 25OHD deficiency rather by nPHPT. In contrast, in autumn, increased PTH concentrations are more likely to reflect nPHPT. We postulate that screening for nPHPT should be done in 25OHD replete subjects, i.e. in autumn rather than in spring.

Rare clinical problem - isolated ACTH deficiency associated with chronic alcohol abuse.

Isolated adrenocorticotropic hormone (ACTH) deficiency (IAD) is a rare pituitary disorder characterized by decreased secretion of ACTH, leading to cortisol deficiency, with normal secretion of other pituitary hormones. Diagnostics remains a challenge due to variable and nonspecific clinical presentation: weakness, weight loss, and low blood pressure. Hyponatremia and anemia are typical abnormalities in basic laboratory tests. Diagnostic procedures for IAD are based on results of low morning cortisol with low/normal ACTH concentrations, with flat response of these hormones in dynamic tests [with insulin/glucagon/corticotropin-releasing hormone (CRH)]. There is also no cortisol response to Synacthen during the standard (not extended) test duration. Several aetiologies lead to the development of IAD. The congenital form is typical of childhood onset. In adults, autoimmune aetiology prevails, including lymphocytic hypophysitis, and rarer - pituitary injury or other lesions in the gland. IAD has recently been demonstrated as a complication in patients receiving therapy with immune checkpoint inhibitors. Also, in the case of IAD, paraneoplastic autoimmune hypophysitis should be considered. Next, alcohol abuse has been reported to be a reason of IAD in single cases. Treatment with oral hydrocortisone usually causes significant improvement. As an example, we present 2 patients diagnosed with IAD. Both were older males, with history of alcohol abuse, long lasting hyponatremia, and weakness. Their clinical state normalized after receiving replacement therapy with hydrocortisone.

Night shift work and osteoporosis - bone turnover markers among female blue-collar workers in Poland.

Osteoporosis is an important public health problem worldwide. Although many factors relating to bone structure have been described so far, the current knowledge on the occupational factors that may affect bone tissue metabolism is strongly limited. Literature data suggest that night shift work, via circadian rhythm disruption, may be considered a potential risk factor. To this date, only five epidemiological studies addressing this problem have been conducted worldwide. The outcomes of three studies confirmed such relationship, namely, a higher fracture risk was found among nurses with a long lifetime duration of night shift work in one study; and a lower bone mineral density was associated with occupational activity during night-time in two studies. In adults, the bone undergoes constant remodelling through bone resorption followed by bone formation. The various molecules released into the circulatory system during these processes are called bone turnover markers. We investigated the possible associations between night shift work and selected bone turnover markers: N-terminal propeptide of type I procollagen (P1NP), C-terminal cross-linked telopeptide of type I collagen (CTX), osteocalcin, osteopontin, fibroblast growth factor 23 (FGF-23) and osteoprotegerin, measured in plasma of 189 female blue-collar workers. A significantly higher bone turnover rate was noted among the women working night shifts than among those working only during the day. This may potentially lead to a future development of osteoporosis in this population even if the macroscopic changes in the bone structure are not detectable. Night shift work is a prevailing occupational characteristics nowadays. It has been estimated that about 15-20% of the working population in Europe and the USA perform work under this system. Thus, the problem of osteoporosis can affect a large part of the working-age population.

The Effect of Recombinant Human TSH on Sclerostin and Other Selected Bone Markers in Patients after Total Thyroidectomy for Differentiated Thyroid Cancer.

The direct effect of TSH on bone metabolism in vivo is difficult to capture as the changes of its concentrations are followed by respective alterations of thyroid hormone levels. We evaluated the effect of recombinant human TSH (rhTSH) on sclerostin and other bone markers in 29 patients after total thyroidectomy for differentiated thyroid cancer (DTC), without any signs of disease recurrence, who received L-thyroxine, most at non-suppressive doses. For two consecutive days, the patients were administered a standard dose of 0.9 mg rhTSH, i.m. Concentrations of sclerostin, osteocalcin, ß-CrossLaps, PTH, and some other parameters, were measured before and five days after the first rhTSH administration. The greater the increase in TSH concentration (∆TSH), the greater the decrease in: ∆sclerostin (r = -0.672; p < 0.001), ∆ß-CrossLaps (r = -0.580; p < 0.001) and ∆osteocalcin (r = -0.405; p = 0.029) levels, were recorded. The degree of TSH increase depended on the baseline PTH (r = 0.651; p < 0.001), age, and creatinine concentrations. rhTSH strongly inhibited bone turnover, thus, TSH-independently of thyroid hormones-exerted a direct protective effect on bone metabolism. Baseline PTH affected the magnitude of TSH increase and the degree of lowering in sclerostin and ß-CrossLaps that suggest factors affecting PTH may play a role in the effect of TSH on the bone.

Effect of Summer Sunshine Exposure on Vitamin D Status in Young and Middle Age Poles: Is 30 ng/mL Vitamin D Cut-Off Really Suitable for the Polish Population?

BACKGROUND: There is no consensus regarding vitamin sufficiency status with either 20 ng/mL or 30 ng/mL sufficiency cut-off. We assessed the effects of summer sunshine exposure on vitamin D status. PARTICIPANTS: We measured vitamin D concentrations, PTH, creatinine, and total calcium in 132 healthy subjects, age 29.36 ± 13.57 years, in spring and autumn. RESULTS: There was an overall increase in vitamin D concentrations from spring to autumn from 18.1 ± 7.39 ng/mL to 24.58 ± 7.72 ng/mL, (p < 0.001), accompanied by a decrease in PTH from 44.4 ± 17.76 pg/mL to 36.6 ± 14.84 pg/mL, (p < 0.001). In spring, only 5.3% of individuals were vitamin D sufficient for a 30 ng/mL cut-off, increasing to 23.2% in autumn (p < 0.001). In contrast, when a 20 ng/mL cut-off was employed, vitamin D sufficiency was found in 34.1% in spring and 66.4% individuals in autumn, respectively, (p < 0.001). In multiple regression analysis, holiday leave was the only significant determinant of vitamin D increase (p < 0.001). CONCLUSIONS: Holiday leave is the strongest determinant of an increase in vitamin D. The majority of healthy individuals fail to reach a 30 ng/mL vitamin D cut-off after summer sunshine exposure. This raises the question, whether such a cut-off is indeed suitable for the Polish population.

Bone Metabolism in Patients Treated for Depression.

BACKGROUND: Depression and osteoporosis are severe public health problems. There are conflicting findings regarding the influence of depression on bone metabolism. The aim of the presented study was to compare bone turnover markers and vitamin D levels between patients treated for depression and healthy controls. PATIENTS AND METHODS: We determined a concentration of osteocalcin, carboxy-terminal telopeptide of type I collagen (ß-CTX), 25-hydroxyvitamin D (25OHD) and 1,25(OH)2D3 in 99 patients, aged 46.9 ± 11 years, treated for depression, as well as in 45 healthy subjects. Depressive status was determined with the Hamilton Depression Scale (HDRS). RESULTS: In patients treated for depression, we demonstrated significantly lower osteocalcin concentrations (p < 0.03) and higher concentration of ß-CTX (result on the border of significance; p = 0.08). Those relationship were stronger in women. The level of 25OHD and 1,25(OH)2D3 did not differ significantly between the examined groups. We observed a negative correlation between the 25OHD and HDRS score after treatment in all patients treated for depression and in subgroups of women and subjects with recurrent depression. CONCLUSIONS: Our results indicate that depression is related to disturbances in bone metabolism, especially in women and patients with recurrent depression, suggesting its role in context of osteoporosis development.

Night shift work and osteoporosis among female blue-collar workers in Poland - a pilot study.

Osteoporosis is an important public health problem worldwide. Although a number of factors that affect bone structure have been described; thus far, the current knowledge of occupational factors that may have an influence on bone tissue metabolism is strongly limited. Published studies indicate night shift work and the related circadian rhythm disruption may be considered as plausible underlying factors. The aim of the present study was to assess the potential association between night shift work and bone mineral density (BMD) among female blue-collar workers in Poland. A cross-sectional study was carried out among 194 female blue-collar workers >40 years of age employed in industrial plants. The operating system of work consisted of three work shifts clockwise rotation: morning (06:00-14:00 h), afternoon (14:00-22:00 h), and night (22:00-06:00 h), with five consecutive shifts per week followed by a free weekend. A questionnaire survey, based on a Polish version of The European vertebral osteoporosis study (EVOS) questionnaire, a validated instrument, was administered. Data on current job characteristics, job seniority, and lifetime duration of night shift work were also collected. BMD of the lumbar spine and hip (both total femur and femoral neck) was measured using dual-energy X-ray absorptiometry. Multivariate linear regression models were run, with bone mineralization parameters as dependent variables, as well as night work characteristics and important confounders. Statistical analysis was performed separately for premenopausal and postmenopausal women. The analyses adjusted for confounders did not reveal any significant differences between current or lifetime experience of night shift work and BMD among both premenopausal and postmenopausal women. However, the outcomes supported the well-established correlation with factors, such as age, BMI, and menopausal status. BMD at the three sites measured was significantly associated with BMI (p < .001) and inversely associated with age (p < .001) in the total study population. Postmenopausal women had significantly lower BMD than did premenopausal women (p < .001). The study findings indicate that in the population of Polish female blue-collar workers, the system of work does not seem to be associated with the development of osteoporosis.

How much insulin resistance in polycystic ovary syndrome? Comparison of HOMA-IR and insulin resistance (Belfiore) index models.

INTRODUCTION: Polycystic ovary syndrome (PCOS), the commonest endocrinopathy of women in reproductive age, is often accompanied by insulin resistance (IR), hirsutism and/or fertility problems. The aim of the study was to assess the prevalence of IR in women diagnosed with PCOS. MATERIAL AND METHODS: The study involved 137 women diagnosed with PCOS, according to the Rotterdam consensus criteria (2003). Insulin resistance was assessed according to the HOMA-IR method and insulin resistance (Belfiore) index (IRI) derived from glucose and insulin during the oral glucose tolerance test. RESULTS: There was a significant (p < 0.0001) but relatively moderate correlation between IRI and HOMA-IR (r = 0.5 and r = 0.57 for a linear and non-linear model, respectively). Insulin resistance was more prevalent according to IRI (49.6%) than according to HOMA-IR (22.6% and 15.8% for 3.46 and 3.8 cut-off points, respectively, p < 0.01). The majority of patients with high HOMA-IR also had high IRI (e.g. 86%, for HOMA > 3.8), but the majority of patients with raised IRI would not be diagnosed as insulin resistant according to HOMA (61.7% and 73.5%, for HOMA-IR3.46 and HOMA-IR3.80, respectively). CONCLUSIONS: The insulin resistance (Belfiore) index indicates more cases of insulin resistance than HOMA-IR in women with PCOS. Therefore, detection of insulin resistance among women with PCOS is highly method-dependent with more severe cases being detected with HOMA-IR than with IRI.

Differences of the Structure of Immune Regulatory Cell Populations between Cellular Material from Sonographically Detected Focal Thyroid Lesions and Peripheral Blood in Humans.

Focal thyroid lesions are common ultrasound findings with the estimated prevalence up to 67% of the population. They form characteristically enveloped regions with individual encapsulated microenvironment that may involve the specific distribution of immune system compounds-especially antigen presenting cells (APC). We analyzed and compared the most potent APC-plasmacytoid and conventional dendritic cells (DCs) subpopulations and three monocyte subpopulations as well as other immune cells-in peripheral blood and local blood of thyroid gland obtained parallelly in patients with focal thyroid lesions using flow cytometry. The analysis revealed significant differences in the distribution of main subsets of assessed cells between peripheral blood and biopsy material. The results support the existence of local, organ-specific immune reaction control networks within thyroid nodules.

Night shift work and osteoporosis: evidence and hypothesis.

Osteoporosis is an important public health problem worldwide. Among the countries with a very high population risk of fractures, there are those with the highest level of economic development. Osteoporotic fractures are the main cause of disability among elderly people, and the resultant disabilities require particularly large financial support associated not only with the direct treatment of the fracture but also with the necessity for long-term rehabilitation and care for the disabled person. Many well-established factors can have impact on bone mass and fracture risk. Recently, it has been hypothesized that working during nighttime which leads to endocrine disorders may have an indirect impact on bone physiology among night shift workers. Therefore, it can be presumed that the night shift work may contribute to the etiology of osteoporosis. The aim of our work was to make a review of the epidemiological evidence on the association between night shift work and bone mineral density or fracture risk as well as to discuss the potential biological mechanisms linking the work under this system with the development of osteoporosis. We have identified only four studies investigating the association between system of work and bone mineral density or fracture risk among workers. The findings of three out of four studies support the hypothesis. None of the studies has investigated a potential relationship between night shift work and bone turnover markers. Given that there have been no epidemiological studies in European countries that would concern working populations and the noticeable difference in the risk of osteoporosis between communities, further studies are warranted to elucidate the problem. It is presumed that further in-depth studies will not only identify the underlying factors of the disease but also contribute to developing guidelines for policy makers and employers for primary prevention of osteoporosis in workplace.

Copeptin as a marker of an altered CRH axis in pituitary disease.

BACKGROUND: Copeptin (pre-proAVP) secreted in equimolar amounts with vasopressin closely reflects vasopressin release. Copeptin has been shown to subtly mirror stress potentially mediated via corticotrophin-releasing hormone. To further test a potential direct interaction of corticotrophin-releasing hormone with copeptin release, which could augment vasopressin effects on pituitary function, we investigated copeptin response to corticotrophin-releasing hormone. PATIENTS AND METHODS: Cortisol, adrenocorticotropin and copeptin were measured in 18 healthy controls and 29 subjects with a history of pituitary disease during standard corticotrophin-releasing hormone test. RESULTS: Patients with previous pituitary disease were subdivided in a group passing the test (P1, n = 20) and failing (P2, n = 9). The overall copeptin response was higher in controls than in subjects with pituitary disease (area under the curve, p = 0.04 for P1 + P2) with a maximum increase in controls from 3.84 ± 2.86 to 12.65 ± 24.87 pmol/L at 30 min, p < 0.05. In contrast, both groups of pituitary patients lacked a significant copeptin response to corticotrophin-releasing hormone, and even in P1, where adrenocorticotropin concentrations increased fourfold (mean, 21.48 vs. 91.53 pg/mL, p < 0.01), copeptin did not respond (e.g., 4.35 ± 5.81 vs. 5.36 ± 6.79 pmol/L, at 30 min, p = ns). CONCLUSIONS: Corticotrophin-releasing hormone is able to stimulate copeptin release in healthy controls suggesting a direct interaction of corticotrophin-releasing hormone and vasopressin/vasopressin. Interestingly, this relation is altered already in the group of pituitary patients who pass the standard corticotrophin-releasing hormone test indicating (1) the corticotrophin-releasing hormone-adrenocorticotropin-cortisol response is largely independent from the vasopressin system, but (2) the corticotrophin-releasing hormone-vasopressin interaction reflected by copeptin may be much more sensitive to reveal subtle alterations in the regulation of pituitary function.

Low dairy calcium intake is associated with overweight and elevated blood pressure in Polish adults, notably in premenopausal women.

OBJECTIVE: Dietary Ca is now being recognized to play an important role not only in skeletal integrity, but also in the regulation of energy and metabolism. The aim of the present study was to estimate the relationship of dairy Ca intake with BMI and blood pressure (BP) in a sample derived from the Polish population. DESIGN: Ca intake was calculated from an interviewer-administered semi-quantitative FFQ. BMI was calculated from measured weight and height, and BP was measured by a physician. SETTING: Cross-sectional epidemiological study on osteoporosis risk factors in Poland. SUBJECTS: Randomly selected healthy adult persons (n 1259; 750 women and 509 men). RESULTS: Dairy Ca intake was significantly lower in individuals with overweight/obesity (BMI≥25·00 kg/m2) and/or with elevated BP (systolic/diastolic ≥140/≥90 mmHg) than in those with normal body mass and BP, respectively. Ca intake was negatively correlated with BMI (r=-0·12, P<0·001), systolic BP (r=-0·11, P<0·001) and diastolic BP (r=-0·08, P<0·01). Daily dairy Ca intake below 1000 mg was a predictor for BMI≥25·0 kg/m2 (OR=1·44, P<0·005). This relationship was stronger in women, particularly premenopausal women. CONCLUSIONS: The obtained results indicate the role of low dairy Ca intake in the development of obesity and hypertension, notably in premenopausal women.

Influence of dietary calcium intake on quantitative and qualitative parameters of bone tissue in Polish adults.

INTRODUCTION: The objective of the study was to assess dietary calcium intake in the Polish population and its influence on selected parameters of bone tissue. MATERIALS AND METHOD: 1,129 osteoporosis treatment-naive subjects, aged 20-80 years, randomly selected, were involved in the study. Bone status was established using densitometry of spine and hip and quantitative ultrasound of the calcaneus. Dietary calcium intake was calculated according to data gathered in a questionnaire. RESULTS: Median calcium intake was 746 mg; 72% of subjects had calcium intake below the recommended dose. Calcium intake correlated negatively with age (r = -0.15; p<0.001) and positively with BMD in the spine (r = 0.06; p<0.05) and in the femoral neck (r = 0.07; p < 0.05). In subjects with the lowest calcium intake, a significantly lower femoral neck BMD and heel stiffness was noticed than in subjects with the highest calcium intake. However, multiple regression analysis showed that dietary calcium was not a predictor of low BMD, both in the hip and spine, as well as of bone stiffness in contrast to age, low BMI and female gender (p<0.0001). In all factors regression analysis, a weak influence of calcium intake on BMD was shown only in the subgroup of premenopausal women (ß = 0.1; p<0.05). CONCLUSIONS: In most subjects, dietary calcium intake was below the recommended dose; however, its influence on bone seems to be weak, except for persons with the greatest deficiency of dietary calcium and the subgroup of premenopausal women.

Hypopituitarism and goitre as endocrine manifestation of Langerhans cell histiocytosis (LCH). Case Report.

Langerhans cell histiocytosis (LCH) in adults is a rare disorder of unknown etiology characterized by monoclonal proliferation of Langerhans cells. It belongs to dendritic cell disorders and occurs in 1-2 adults per million. The most common endocrine manifestation of classical LCH is associated with the posterior pituitary, with clinical symptoms of diabetes insipidus. Less than 80 reported cases of LCH involving the thyroid gland have been published so far. We present the case of a 39 years old woman with 10 years history of diabetes insipidus and secondary amenorrhoea, which appeared after second delivery. She was suspected for lymphocytic inflammation of pituitary and she was administered steroid treatment. She was also treated symptomatically with desmopressin, L-thyroxine, estrogen and progestagen replacement therapy due to diabetes insipidus, secondary hypothyroidism and hypogonadotropic hypogonadism. In September 2014, she noticed a painless, firm tumour of the neck. Ultrasound (US) examination demonstrated bilateral, solid, hypoechogenic thyroid nodules. The result of fine-needle aspiration biopsy (FNAB) was not diagnostic. Due to rapid progression and US image of the tumour, she was referred for surgery. In postoperative histopathology tumour cells were positive for CD1a and S-100 protein, therefore diagnosis of LCH was established. Postoperatively, the results of thoracic computed tomography scan, abdominal US and bone scintigraphy revealed no evidence of multifocal disease. We have not observed any disease recurrence in the patient after a year of follow-up in postoperative course. This case illustrates diagnostic and therapeutic difficulties in patient with LCH.

Copeptin under glucagon stimulation.

Stimulation of growth hormone (GH) and adrenocorticotropic hormone (ACTH) secretion by glucagon is a standard procedure to assess pituitary dysfunction but the pathomechanism of glucagon action remains unclear. As arginine vasopressin (AVP) may act on the release of both, GH and ACTH, we tested here the role of AVP in GST by measuring a stable precursor fragment, copeptin, which is stoichiometrically secreted with AVP in a 1:1 ratio. ACTH, cortisol, GH, and copeptin were measured at 0, 60, 90, 120, 150, and 180 min during GST in 79 subjects: healthy controls (Group 1, n = 32), subjects with pituitary disease, but with adequate cortisol and GH responses during GST (Group 2, n = 29), and those with overt hypopituitarism (Group 3, n = 18). Copeptin concentrations significantly increased over baseline 150 and 180 min following glucagon stimulation in controls and patients with intact pituitary function but not in hypopituitarism. Copeptin concentrations were stimulated over time and the maximal increment correlated with ACTH, while correlations between copeptin and GH were weaker. Interestingly, copeptin as well as GH secretion was significantly attenuated when comparing subjects within the highest to those in the lowest BMI quartile (p < 0.05). Copeptin is significantly released following glucagon stimulation. As this release is BMI-dependent, the time-dependent relation between copeptin and GH may be obscured, whereas the close relation to ACTH suggests that AVP/copeptin release might be linked to the activation of the adrenal axis.