Yasin Simsek

A comparison of low‐dose ACTH, glucagon stimulation and insulin tolerance test in patients with pituitary disorders

Diagnosis of secondary adrenal insufficiency and GH deficiency requires evaluation by dynamic stimulation tests in most cases. Although insulin tolerance test (ITT) is accepted as the gold‐standard test for the evaluation of both hypothalamo‐pituitary‐adrenal (HPA) and (GH)‐IGF‐1 axes, the test is cumbersome. In clinical practice, low‐dose adrenocorticotrophic hormone (ACTH) stimulation test is a sensitive, safe and easily applicable alternative to ITT. Although it takes more time, glucagon stimulation test (GST) is also a good alternative to ITT and can evaluate both axes.

Etiopathogenesis of Sheehan’s Syndrome: Roles of Coagulation Factors and TNF-Alpha

Sheehans Syndrome (SS) is defined as pituitary hormone deficiency due to ischemic infarction of the pituitary gland as a result of massive postpartum uterine hemorrhage. Herein, we aimed to investigate the roles of Factor II (G20210A), Factor V (G1691A), MTHFR (C677T and A1298C), PAI-1 4G/5G, and TNF-α (−308  G > A) gene polymorphisms in the etiopathogenesis of SS. Venous blood samples were obtained from 53 cases with SS and 43 healthy women. Standard methods were used to extract the genomic DNAs. Factor II (G20210A), Factor V (G1691A), and MTHFR (C677T and A1298C) polymorphisms were identified by real-time PCR. PAI-1 4G/5G and TNF-α (−308  G > A) gene polymorphisms were detected with polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods. According to statistical analysis, none of the polymorphisms were found to be significantly higher in the SS group compared to the control group. Hence, we suggest that genetic factors other than Factor II, Factor V, MTHFR, PAI-1, and TNF-α gene polymorphisms should be researched in the etiopathogenesis of SS.

Genetic expressions of thrombophilic factors in patients with Sheehan’s syndrome

Abstract Purpose: The aim of this study was to evaluate the roles of factors associated with coagulation in the etiology and pathogenesis of Sheehan’s syndrome (SS) which is a frequent cause of hypopituitarism in underdeveloped and developing regions of the world. Methods: Mean prothrombin time (PT), activated partial thromboplastin time (APTT) and expression levels of genes, which included methylenetetrahydrofolate reductase (MTHFR), angiotensin I converting enzyme (ACE), coagulation factor V (FV), FVII, FVIII and FIX in 44 patients with SS were compared with 43 healthy subjects. Results: The mean expression level of the ACE gene was significantly lower, while that of the FV gene was significantly higher in the patients with SS. No significant difference was found between the patients with SS and the healthy subjects in the comparisons of the remaining gene expression values, as well as in the PT and APTT values. Conclusion: An increased expression of the FV gene may be a contributing factor for the development of SS in some patients. Further studies are required to clarify the roles of coagulation disorders in the development of SS.

Prognostic factors obtained from long-term follow-up of pituitary adenomas and other sellar tumors.

AIM Pituitary adenomas do not have a single factor of aggressive behavior or recurrence. The objective of this study was to determine factors influencing the prognosis in pituitary adenomas. MATERIAL AND METHODS 243 patients who were operated between January 2000 and June 2012 were included in this retrospective study. Demographic data, age at diagnosis, date of diagnosis, date of operation, type of operation, post-operative medications, pre- and postoperative hormone levels, and MRI findings were evaluated in each patient. RESULTS The rate of total resection of sellar tumors was less than 50% in our patient population. The prognosis was better in cases with total resection. Tumor size was a poor prognostic factor in sellar tumors. Female sex was a poor prognostic factor in acromegaly and male sex in prolactinoma. The prognosis was worse in patients with cavernous sinus invasion. In acromegaly, pre-operative level of 850 ng/ml for IGF-1 was noted as a possible prognostic cut-off value. CONCLUSION Long-term follow-up results of our study suggest that factors common to all sellar tumors including tumor type, tumor size, total resection, and cavernous sinus invasion and tumor type-specific factors including sex and hormone levels play important roles in the prognosis.

Is Positive Staining of Non-Functioning Pituitary Adenomas for Luteinizing Hormone Associated with a Poor Prognosis?

AIM The aim of this study was to assess the relationships among immunohistochemical staining patterns and prognostic factors in patients with non-functioning pituitary adenoma (NFPA). MATERIAL AND METHODS The study included 103 patients who had undergone pituitary surgery for NFPAs. The prognostic factors evaluated were initial tumor size, cavernous sinus invasion, compression of the optic chiasm, recurrence, residual tissue, reoperation, and hypopituitarism. RESULTS Recurrence rates were higher for NFPAs with large initial tumor volume and preoperative cavernous sinus invasion. Tumor recurrence rates were higher for NPFAs positive (55.6%) than negative (10.3%) for luteinizing hormone (LH). Reoperation rate, but not recurrence rate, was higher in patients with tumors positive than negative for follicle-stimulating hormone (FSH) group. Recurrence and reoperation rates were lowest in patients with null-cell adenomas. CONCLUSION In contrast to previous studies, we observed a higher recurrence rate in LH-positive than in LH-negative adenomas. To our knowledge, this is the first study showing an association between LH positivity and poorer prognosis; and in addition, optimal outcomes in patients with null-cell adenomas. Thus, additional studies are required to assess the relationship between LH positivity and poor prognosis in patients with NFPAs.

A Pregnant Woman Who Underwent Laparoscopic Adrenalectomy due to Cushing’s Syndrome

Cushings syndrome (CS) may lead to severe maternal and fetal morbidities and even mortalities in pregnancy. However, pregnancy complicates the diagnosis and treatment of CS. This study describes a 26-year-old pregnant woman admitted with hypertension-induced headache. Hormonal analyses performed due to her cushingoid phenotype revealed a diagnosis of adrenocorticotropic hormone- (ACTH-) independent CS. MRI showed a 3.5 cm adenoma in her right adrenal gland. After preoperative metyrapone therapy, she underwent a successful unilateral laparoscopic adrenalectomy at 14-week gestation. Although she had a temporary postoperative adrenal insufficiency, hormonal analyses showed that she has been in remission since delivery. Findings in this patient, as well as those in previous patients, indicate that pregnancy is not an absolute contraindication for laparoscopic adrenalectomy. Rather, such surgery should be considered a safe and efficient treatment method for pregnant women with cortisol-secreting adrenal adenomas.