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  • Author: Fahrettin Kelestimur x
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Yilmaz Şahin, Demet Ayata and Fahrettin Keleştimur

Abstract

Objective: To determine whether hyperinsulinism affects cytochrome P450c 17α activity by investigating the correlation between 17–hydroxyprogesterone (17–OHP) hyper-responsiveness to the gonadotropin-releasing hormone (GnRH) agonist, buserelin, and the insulin response to oral glucose in polycystic ovary syndrome (PCOS).

Design: Ultrasound, clinical and hormonal parameters were used to define PCOS in this prospective clinical study. We investigated the correlation between the 17–OHP response to buserelin testing and the insulin response to oral glucose in PCOS.

Methods: Twenty-eight women with PCOS and eighteen normal women were included in the study. 17–OHP response to buserelin, and insulin and C–peptide responses to oral glucose were measured. Results: Twenty–live women with PCOS had an increased 17–OHP response. The PCOS patients showed significantly higher mean post–glucose load insulin and C–peptide levels than controls (P<0·05). No significant correlations were found between basal 17–OHP and fasting insulin or fasting C–peptide, between peak 17–OHP and fasting insulin, peak insulin or peak C–peptide, between 17–OHP area under the curve (AUC) and insulin AUC or C–peptide AUC, and between percent increment in 17–OHP and insulin AUC or C–peptide AUC (P >0·05).

Conclusions: Lack of a relationship between the 17–OHP response to the GnRH agonist buserelin and hyperinsulinism suggests that hyperinsulinism may not play a role in the dysregulation of the cytochrome P450c17α enzyme seen in PCOS.

European Journal of Endocrinology 136 410–415

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Hulusi Atmaca, Fatih Tanriverdi, Cumali Gokce, Kursad Unluhizarci and Fahrettin Kelestimur

Objective: We studied posterior pituitary function in 27 patients with Sheehan’s syndrome and 14 controls.

Design: All patients were investigated by water deprivation test and 26 of them by 5% hypertonic saline infusion test. None of the patients had symptoms of diabetes insipidus and all patients were on adequate glucocorticoid and thyroid hormone replacement therapy before testing.

Results: According to dehydration test, 8 (29.6%) patients had partial diabetes insipidus (PDI group) and 19 (70.3%) had normal response (non-DI group). During the 5% hypertonic saline infusion test, the maximal plasma osmolality was higher in PDI (305 ± 4.3) and non-DI (308 ± 1.7) groups when compared with controls (298 ± 1.7 mOsm/kg; P < 0.005), but the maximal urine osmolality was lower in PDI group (565 ± 37) than in non-DI (708 ± 45) and control (683 ± 17 mOsm/kg) groups (P < 0.05). The osmotic threshold for thirst perception was higher in PDI (296 ± 4.3) and non-DI (298 ± 1.4) groups when compared with control group (287 ± 1.5 mOsm/kg) (P < 0.005). Basal plasma osmolalities were also higher in PDI (294 ± 1.0) and non-DI (297 ± 1.1) groups than in controls (288 ± 1.2 mOsm/kg; P < 0.001).

Conclusions: Our findings demonstrated that patients with Sheehan’s syndrome have an impairment of neurohypophyseal function. The thirst center may be affected by ischemic damage and the osmotic threshold for the onset of thirst in patients with Sheehan’s syndrome is increased.

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Hulusi Atmaca, Fatih Tanriverdi, Kursad Unluhizarci, Fahri Bayram and Fahrettin Kelestimur

Objective: Some patients with hyperandrogenemia had no identifiable cause, which was named as idiopathic hyperandrogenemia (IHA). The role of the adrenal glands in these patients was investigated.

Design: Clinical study in patients with IHA at the Endocrinology Department of a University Hospital.

Patient(s): In this study, 26 pre-menopausal women with IHA and 20 healthy women were included. Basal hormonal investigations, ACTH test and a 75 g oral glucose tolerance test (OGTT) were performed. Basal levels of total testosterone, free testosterone, androstenedione (A4), sex hormone-binding globulin, DHEA sulfate (DHEAS), cortisol, 17-hydroxyprogesterone (17-OHP), 11-deoxycortisol (11-S) and ACTH-stimulated levels of cortisol, A4, DHEAS, 17-OHP, and 11-S were measured. Additionally, glucose and insulin responses to OGTT were obtained.

Results: The patients and the control subjects had similar age and body mass index. Peak and area under the curve (AUC) responses of 11-S (P < 0.05), DHEAS (P < 0.005), and A4 (peak, P < 0.005; AUC, P < 0.001) to ACTH test were significantly higher in the patients with IHA than in the control subjects. There was a significant correlation between the basal DHEAS levels, peak 11-S, and AUC11-S, in response to ACTH-stimulation test in patients with IHA (P < 0.005, r, 0.6). Four (16.6%) patients with IHA had glucose intolerance.

Conclusion: Our data suggest that adrenal androgen excess may playanimportant role in patients with IHA and these patients exhibit increased prevalence of glucose intolerance.

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Fahrettin Keleştimur, Peter Jonsson, Senay Molvalilar, Jose Manuel Gomez, Christoph J Auernhammer, Ramiz Colak, Maria Koltowska-Häggström and Miklos I Goth

Objective: Sheehan’s syndrome occurs as a result of ischaemic pituitary necrosis due to severe postpartum haemorrhage. It is one of the most important causes of hypopituitarism, and hence growth hormone deficiency (GHD), in developing countries. However, little is known about the effects of growth hormone (GH) replacement therapy in patients with Sheehan’s syndrome.

Design: The demographic background characteristics of 91 GH-deficient patients with Sheehan’s syndrome (mean age ± s.d., 46.3 ± 9.4 years) were compared with those of a group of 156 GH-deficient women (mean age ± s.d., 51.5 ± 13.1 years) with a non-functional pituitary adenoma (NFPA). The baseline characteristics and the effects of 2 years of GH replacement therapy were also studied in the 91 patients with Sheehan’s syndrome and an age-matched group of 100 women with NFPA (mean age ± s.d. 44.5 ± 10.2 years).

Results: All patients were enrolled in KIMS (Pfizer International Metabolic Database). Patients with Sheehan’s syndrome were significantly younger at pituitary disorder onset, diagnosis of GHD and at entry into KIMS than patients with NFPA (P < 0.01), and had significantly lower insulin-like growth factor I levels (P < 0.001). At baseline, quality of life (QoL) was significantly (P < 0.05) reduced in patients with Sheehan’s syndrome compared with those with NFPA (P < 0.001). With regard to treatment effects, lean body mass increased significantly (P < 0.05), QoL improved significantly (P < 0.05) and total and low-density lipoprotein-cholesterol decreased significantly (P < 0.05) in patients with Sheehan’s syndrome after 1 year of GH replacement therapy. Similar significant changes in QoL and lipid profiles occurred in patients with NFPA after 2 years of GH replacement. Blood pressure remained unchanged in patients with Sheehan’s syndrome, but decreased significantly (P < 0.01) in the group with NFPA after 1 year, before returning to pretreatment levels at 2 years.

Conclusions: In conclusion, patients with Sheehan’s syndrome have more severe GHD compared with individuals with NFPA. GH replacement therapy in patients with Sheehan’s syndrome may have beneficial effects on QoL, body composition and lipid profile.

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Halit Diri, Fatih Tanriverdi, Zuleyha Karaca, Serkan Senol, Kursad Unluhizarci, Ahmet Candan Durak, Hulusi Atmaca and Fahrettin Kelestimur

Objective

Sheehan's syndrome (SS) is a well-known cause of hypopituitarism resulting from postpartum pituitary necrosis. Because of its rarity in Western society, its diagnosis is often overlooked. We aimed to investigate the clinical, laboratory, and radiological aspects of SS in a large number of patients.

Study design

A retrospective assessment of the medical records of 114 patients with SS was conducted. In addition, sella turcica volumes of 29 healthy women were compared with those of patients by magnetic resonance imaging examinations.

Results

The mean period of diagnostic delay was 19.7 years in patients with SS. It was found that 52.6% of patients had nonspecific complaints, 30.7% had complaints related to adrenal insufficiency, and 9.6% had complaints related to hypogonadism when diagnosed. At the time of diagnosis, 55.3% of the patients had panhypopituitarism, while 44.7% had partial hypopituitarism. The number of deficient hormones was found to be increased over the years. None of the patients whose basal prolactin was below 4.0 ng/ml had adequate prolactin responses to TRH test, while all patients whose basal prolactin was above 7.8 ng/ml had adequate responses. Mean sella volume was found to be significantly lower in the SS group (340.5±214 mm3) than that in the healthy group (602.5±192 mm3).

Conclusions

SS is a common cause of hypopituitarism in underdeveloped and developing countries. The main reasons for diagnostic delay seem to be the high frequency of patients with nonspecific complaints and neglect of SS. In addition, the TRH stimulation test was found to have a high sensitivity and specificity to recognize PRL deficiency. Furthermore, small sella size may have an important contributing role in the etiopathogenesis of SS.

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Seher Polat, Alexandra Kulle, Züleyha Karaca, Ilker Akkurt, Selim Kurtoglu, Fahrettin Kelestimur, Joachim Grötzinger, Paul-Martin Holterhus and Felix G Riepe

Background

Congenital adrenal hyperplasia (CAH) is one of the most common autosomal recessive inherited endocrine diseases. Steroid 11β-hydroxylase (P450c11) deficiency (11OHD) is the second most common form of CAH.

Aim

The aim of the study was to study the functional consequences of three novel CYP11B1 gene mutations (p.His125Thrfs*8, p.Leu463_Leu464dup and p.Ser150Leu) detected in patients suffering from 11OHD and to correlate this data with the clinical phenotype.

Methods

Functional analyses were done by using a HEK293 cell in vitro expression system comparing WT with mutant P450c11 activity. Mutant proteins were examined in silico to study their effect on the three-dimensional structure of the protein.

Results

Two mutations (p.His125Thrfs*8 and p.Leu463_Leu464dup) detected in patients with classic 11OHD showed a complete loss of P450c11 activity. The mutation (p.Ser150Leu) detected in a patient with non-classic 11OHD showed partial functional impairment with 19% of WT activity.

Conclusion

Functional mutation analysis enables the correlation of novel CYP11B1 mutations to the classic and non-classic 11OHD phenotype respectively. Mutations causing a non-classic phenotype show typically partial impairment due to reduced maximum reaction velocity comparable with non-classic mutations in 21-hydroxylase deficiency. The increasing number of mutations associated with non-classic 11OHD illustrate that this disease should be considered as diagnosis in patients with otherwise unexplained hyperandrogenism.

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Annamaria De Bellis, Fahrettin Kelestimur, Antonio Agostino Sinisi, Giuseppe Ruocco, Gilda Tirelli, Marina Battaglia, Giuseppe Bellastella, Giovanni Conzo, Fatih Tanriverdi, Kursad Unluhizarci, Antonio Bizzarro and Antonio Bellastella

Objective

While anti-pituitary antibodies (APAs) were detected in some patients with Sheehan's syndrome (SS) suggesting an autoimmune pituitary involvement in the development of their hypopituitarism, hypothalamic cell anti-hypothalamus antibodies (AHAs) have not been investigated so far.

Design

The aim of this study was to evaluate the presence of AHA and APA in SS patients to verify whether an autoimmune hypothalamic–pituitary process can contribute to their late hypopituitarism.

Methods

Twenty women with SS with a duration of disease ranging from 3 to 40 years (median 25.5 years) were enrolled into the study. Out of 20 patients, 12 (60%) had panhypopituitarism and the others had partial hypopituitarism well corrected with appropriate replacement therapy. None of them had clinical central diabetes insipidus. AHA and APA were investigated by immunofluorescence method in all patients. In addition, a four-layer immunofluorescence method was used to verify whether AHA immunostained vasopressin-secreting cells (AVP-c) or not.

Results

AHAs were found in 8 out of 20 (40%) and APAs in 7 out of 20 (35%) patients with titers ranging from 1:32 to 1:128 and 1:16 to 1:32 respectively; however, in none of these positive patients AHA immunostained vasopressin cells. None of controls resulted positive for both antibodies.

Conclusions

Patients with SS, even many years after the onset of SS, can show antibodies to pituitary and/or hypothalamic but not AVP-secreting cells. Antibodies to unknown hypothalamic cells (releasing factor-secreting cells) other than APAs suggest that an autoimmune process involving both the hypothalamus and pituitary gland may contribute to late pituitary dysfunction in SS patients.

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Fatih Tanriverdi, Annamaria De Bellis, Marina Battaglia, Giuseppe Bellastella, Antonio Bizzarro, Antonio A Sinisi, Antonio Bellastella, Kursad Unluhizarci, Ahmet Selcuklu, Felipe F Casanueva and Fahrettin Kelestimur

Objective

Current data clearly demonstrate that sports-related chronic repetitive head trauma due to boxing might result in hypopituitarism. However, the mechanism of sports-related traumatic brain injury-induced pituitary dysfunction is still unclear. In order to understand whether autoimmune mechanisms could play a role in the pituitary dysfunction due to sports-related head trauma, we investigated the presence of antipituitary antibodies (APAs) and antihypothalamus antibodies (AHAs) in amateur boxers.

Patients and design

Sixty-one actively competing (n=44) or retired (n=17) male boxers (mean age, 26 years; range, 17–53) who had been evaluated regarding pituitary functions previously were included in the study. In all boxers and in 60 age/sex-similar normal controls, AHAs and APAs were investigated by an indirect immunofluorescence method.

Results

AHAs were detected in 13 of 61 boxers (21.3%), and APAs were detected in 14 of 61 boxers (22.9%), but in none of the normal controls. Pituitary dysfunction was significantly higher in AHA-positive boxers (46.2%) than in AHA-negative boxers (10.4%) (P=0.003). There was a significant association between AHA positivity and hypopituitarism due to boxing (odds ratio: 7.37, 95% confidence interval 1.8–30.8). There was no significant association between APA positivity and hypopituitarism.

Conclusions

This study demonstrates for the first time the presence of AHAs and APAs in boxers who were exposed to sports-related head trauma. Moreover, the present investigation provides preliminary evidence that AHAs are associated with the development of pituitary dysfunction in boxers, thus suggesting that autoimmunity may have a role in the pathogenesis.

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Serpil Taheri, Gokmen Zararsiz, Sulbiye Karaburgu, Murat Borlu, Mahmut Tuncay Ozgun, Zuleyha Karaca, Fatih Tanriverdi, Munis Dundar, Fahrettin Kelestimur and Kursad Unluhizarci

Objective

Hirsutism results from hyperandrogenemia and/or exaggerated androgen responsiveness. Among various causes of hirsutism, some patients do not exhibit androgen excess which is called idiopathic hirsutism (IH). The pathogenesis of IH could not so far be clearly established.

Design

To investigate the mRNA expression of aromatase enzyme and the other enzymes having functional roles in the steroidogenic pathway, in freshly obtained skin tissue from subumbilical skin and the arm of the patients with IH and healthy women.

Methods

Twenty-one women with IH and 15 healthy women were included in the study. We aimed to determine mRNA expressions of genes associated with local androgen synthesis and metabolism (CYP11A1, STS, CYP19A1, SRD5A1, SRD5A2, HSD3B1, AR, COMT, ESR1, ESR2, HSD3B2, CYP17A1, SULT2A1, SULT1E1, HSD17B2, IL6, TGFB1, TNFA) from skin biopsy and blood samples of patients with IH and the data compared with healthy subjects.

Results

Patients with IH exhibit significantly lower interleukin 6 (IL6) mRNA expression and higher steroid sulphatase (STS) and hydroxysteroid (17beta) dehydrogenase 2 (HSD17B2), gene mRNA expression, respectively, in the subumbilical region skin biopsies. Similarly, patients with IH exhibit significantly lower IL6 mRNA expression and higher STS and HSD17B2 gene mRNA expression, respectively, in the arm skin compared to healthy women's subumbilical region.

Conclusions

In both arm and subumbilical skin biopsy of patients with IH, we observed an up-regulation of HSD17B2 and STS, decreased IL6 mRNA expression, probably determining an increase in the local amount of active androgens, which could then be used as substrate for other androgen metabolic routes.

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Fatih Tanriverdi, Annamaria De Bellis, Antonio Bizzarro, Antonio Agostino Sinisi, Giuseppe Bellastella, Elena Pane, Antonio Bellastella, Kursad Unluhizarci, Ahmet Selcuklu, Felipe F Casanueva and Fahrettin Kelestimur

Objective

Traumatic brain injury (TBI) is a devastating public health problem that may result in hypopituitarism. However, the mechanisms responsible for hypothalamic–pituitary dysfunction due to TBI are still unclear. Although the antibodies against neurons have been demonstrated in injured animal studies, investigations regarding the occurrence of antipituitary antibodies (APAs) in patients with TBI are lacking in the literature. In order to investigate whether autoimmune mechanisms could play a role in the pituitary dysfunction after TBI, we have planned this study aimed at investigating the presence of APA at the third year of TBI and association between the TBI-induced hypopituitarism and APA.

Patients and design

Twenty-nine (25 males and 4 females; age 36.5±2.3 years) patients who had completed a 3-year follow-up after TBI were included in the present study. APA and pituitary function were evaluated in all the patients 3 years after TBI; moreover, APAs were tested also in sera of 60 age-/sex-matched normal controls. The APAs were investigated by an indirect immunofluorescence method.

Results

APAs were detected in 13 out of the 29 TBI patients (44.8%), but in none of the normal controls. Pituitary dysfunction development ratio was significantly higher in APA-positive patients (46.2%) when compared with APA-negative ones (12.5%; P=0.04). There was a significant association between APA positivity and hypopituitarism due to TBI (odds ratio: 2.25, 95% confidence intervals 1.1–4.6). Moreover, there was a significant positive correlation (r=0.74, P=0.004) between APA titer ratio and peak GH response to GHRH+GH related peptide (GHRP)-6 test, suggesting that high APA titers were associated with low GH response to GHRH+GHRP-6 test.

Conclusions

This study shows for the first time the presence of the APA in TBI patients 3 years after head trauma. Moreover, present investigation indicates preliminary evidence that APA may be associated with the development of TBI-induced pituitary dysfunction, thus suggesting that autoimmunity may contribute in the development of TBI-induced hypopituitarism. The presence of the association between APA and TBI-induced hypopituitarism may provide a new point of view in this field and promote further clinical and experimental studies.