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Stephan Petersenn - One of the best experts on this subject based on the ideXlab platform.
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recovery of pituitary function in the late postoperative phase after pituitary surgery results of dynamic Testing in patients with pituitary disease by Insulin Tolerance Test 3 and 12 months after surgery
European Journal of Endocrinology, 2010Co-Authors: C Berg, H Lahner, Timo Meinel, Klaus Mann, Stephan PetersennAbstract:The Insulin Tolerance Test (ITT) is considered the gold standard for assessment of GH and ACTH reserve in patients with pituitary disease following pituitary surgery and is usually performed after 6–12 weeks. However, abnormal axes may not be completely recovered by then. The aim of this study was to evaluate dynamic Testing 3 and 12 months after transsphenoidal pituitary surgery. Design and patients: Serial dynamic Testing was performed in 36 patients (13 women, age 18–78) at 3 and 12 months after transsphenoidal surgery. Results: Compared with 3-month results, median GH peak levels during ITT after 12 months increased by 38% (P!0.05). In patients initially classified as GH deficiency (GHD), median GH peak increased after 12 months by 23% (P!0.05). At 3 and 12 months, 36% (13/36) and 47% (17/36) were GH sufficient respectively. Median cortisol peak levels after 12 months increased by 17% (P!0.01) compared with 3-month ITT. In ACTH-insufficient (AI) patients, peak cortisol levels increased significantly by 12% (P!0.05) at 12 months, and in ACTH-sufficient patients, peak cortisol levels increased significantly by 13% (P!0.05). At 12 months, there was recovery from AI in 11% of the patients, and recovery from GHD in 11% of patients. Conclusions: Serial dynamic Testing results in a change in classification by ITT results in a relevant proportion of patients. Dynamic Testing should be repeated during follow-up.
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diagnostic utility of the glucagon stimulation Test in comparison to the Insulin Tolerance Test in patients following pituitary surgery
European Journal of Endocrinology, 2010Co-Authors: C Berg, H Lahner, Timo Meinel, Ali Yuece, Klaus Mann, Stephan PetersennAbstract:Objective: The glucagon stimulation Test (GST) like the Insulin Tolerance Test (ITT) stimulates both ACTH and GH secretion. However, there are limited data with modern assays on sensitivity and specificity for GST in comparison to ITT. The aim of this study was to evaluate the diagnostic utility of the GST for GH deficiency (GHD) and adrenal insufficiency (AI) in patients following pituitary surgery. Design and patients: ITT and GST were performed within 7 days in 49 patients at least 3 months after transsphenoidal surgery. Serum GH and cortisol were measured by Immulite 2000 assay (Siemens AG). Receiver-operating characteristic (ROC) analysis was performed to identify the thresholds for GST. Results: In ITT, 18/49 cases were classified as AI. ROC analysis revealed a peak cortisol value O599 nmol/l in GST for adrenal sufficiency with 100% specificity and 32% sensitivity, and a peak cortisol !277 nmol/l with O95% specificity and 72% sensitivity for AI. Of the 49 subjects, 25 (51%) demonstrated levels between these cut-offs and could not be diagnosed by GST alone with sufficient accuracy. Regarding GHD, 21/49 cases were classified as insufficient by ITT. ROC analysis revealed a cut-off of 2.5 ng/ml with 95% sensitivity and 79% specificity. Of the 49 cases, seven (14%) were discordant in terms of defining GHD, with six subjects being treated for GHD according to GSTalthough being sufficient in ITT. Conclusion: In our prospective series of patients with pituitary disease, GST is a potential alternative Test for the assessment of GH reserve, but is a poor Test for ACTH reserve. Test-specific cut-offs should be applied to avoid misinterpretation.
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diagnosis of secondary adrenal insufficiency unstimulated early morning cortisol in saliva and serum in comparison with the Insulin Tolerance Test
Hormone and Metabolic Research, 2009Co-Authors: Timo Deutschbein, K. Mann, Nicole Unger, Stephan PetersennAbstract:Unstimulated early morning cortisol has been suggested as a first line parameter to assess adrenal function in patients with suspected secondary adrenal insufficiency. The measurement of basal salivary cortisol (BSaC) instead of basal serum cortisol (BSeC) offers some advantages, such as painless sampling and the determination of the free hormone. The objective of this study was to evaluate the diagnostic value of BSeC and BSaC in comparison to the Insulin Tolerance Test (ITT). Seventy-seven patients with hypothalamic-pituitary disease and 184 healthy controls were enrolled. ITT were performed in patients, and BSeC as well as BSaC levels were measured in patients and controls. Upper and lower thresholds (with ≥95% specificity either for adrenal sufficiency or adrenal insufficiency) were calculated by ROC analysis both for BSeC and BSaC. The ITT identified 41 patients as adrenal insufficient and 36 patients as adrenal sufficient. Upper and lower cutoffs were 470 and 103 nmol/l for BSeC, and 21.1 and 5.0 nmol/l for BSaC, respectively. Thereby, basal cortisol allowed a highly specific diagnosis (i.e., similar to the ITT result) in either 23% (BSeC) or 27% (BSaC) of patients. We suggest the determination of unstimulated early morning cortisol as first-line screening method for the diagnosis of secondary adrenal insufficiency. If upper and lower cutoffs are used, dynamic Testing could be obviated in about one fourth of cases. Due to its easy and painless collection BSaC may be preferable to BSeC.
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diagnosis of adrenal insufficiency evaluation of the corticotropin releasing hormone Test and basal serum cortisol in comparison to the Insulin Tolerance Test in patients with hypothalamic pituitary adrenal disease
The Journal of Clinical Endocrinology and Metabolism, 2003Co-Authors: Lopez I Schmidt, H Lahner, K. Mann, Stephan PetersennAbstract:The aim of the study was to evaluate the diagnostic value of the human CRH Test and the basal morning serum cortisol for the diagnosis of adrenal insufficiency. Putative peak cortisol cut points for the CRH Test and basal cortisol cut points were determined by receiver operating characteristic (ROC) analysis with the Insulin Tolerance Test as reference Test. Fifty-four patients with suspected hypothalamic-pituitary-adrenal disease were Tested. In 20 healthy controls, CRH led to a mean peak cortisol of 594.8 ± 21.7 nmol/liter. The lower limit of a normal response was calculated as 400 nmol/liter. ROC analysis of peak cortisol levels during CRH Testing of patients with suspected hypothalamic-pituitary-adrenal disease suggested an optimal peak cortisol cut point of ≤377 nmol/liter for the diagnosis of adrenal insufficiency and a 96% specificity but poor sensitivity of 76%. The baseline cortisol in the healthy control group showed a mean of 439.3 ± 24.9 nmol/liter, resulting in a lower limit of 267 nmol/liter...
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diagnosis of adrenal insufficiency evaluation of the corticotropin releasing hormone Test and basal serum cortisol in comparison to the Insulin Tolerance Test in patients with hypothalamic pituitary adrenal disease
The Journal of Clinical Endocrinology and Metabolism, 2003Co-Authors: Lopez I Schmidt, H Lahner, K. Mann, Stephan PetersennAbstract:The aim of the study was to evaluate the diagnostic value of the human CRH Test and the basal morning serum cortisol for the diagnosis of adrenal insufficiency. Putative peak cortisol cut points for the CRH Test and basal cortisol cut points were determined by receiver operating characteristic (ROC) analysis with the Insulin Tolerance Test as reference Test. Fifty-four patients with suspected hypothalamic-pituitary-adrenal disease were Tested. In 20 healthy controls, CRH led to a mean peak cortisol of 594.8 +/- 21.7 nmol/liter. The lower limit of a normal response was calculated as 400 nmol/liter. ROC analysis of peak cortisol levels during CRH Testing of patients with suspected hypothalamic-pituitary-adrenal disease suggested an optimal peak cortisol cut point of < or 377 nmol/liter for the diagnosis of adrenal insufficiency and a 96% specificity but poor sensitivity of 76%. The baseline cortisol in the healthy control group showed a mean of 439.3 +/- 24.9 nmol/liter, resulting in a lower limit of 267 nmol/liter. ROC analysis of patients suggested the highest accuracy for basal cortisol levels of 285 nmol/liter or more for the diagnosis of adrenal insufficiency (100% sensitivity and 61% specificity). Within this patient group, a cortisol of more than 98 nmol/liter excluded adrenal insufficiency among those without the disorder, yielding 100% specificity. Using these criteria of upper (285 nmol/liter) and lower (98 nmol/liter) cut-off points with high sensitivity and specificity can reduce the number of individuals who need provocative Tests. Basal cortisol is less expensive, and we therefore suggest to use it as a first-line Test of adrenal insufficiency. Because of the low sensitivity of the human CRH Test, we do not recommend it as a second Test.
Fahrettin Kelestimur - One of the best experts on this subject based on the ideXlab platform.
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a comparison of low dose acth glucagon stimulation and Insulin Tolerance Test in patients with pituitary disorders
Clinical Endocrinology, 2015Co-Authors: Yasin Simsek, Zuleyha Karaca, Fatih Tanriverdi, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin KelestimurAbstract:SummaryContext 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. Objective The primary aim of this study was to compare the ITT, low-dose ACTH and GSTs in the evaluation of HPA and GH-IGF-1 axes in patients with pituitary disorders and to evaluate the repeatability of all three Tests. Design ITT, low-dose ACTH and GSTs were performed in all 129 patients, and the Tests were repeated in 66 of these patients. Setting Erciyes University Medical School, Department of Endocrinology. Patients or Other Participants One hundred and twenty-nine adult patients (76 women, 53 men) with pituitary disorder were included in the study. Main Outcome Measure(s) The cortisol and GH responses of patients to dynamic Tests. Results Peak cortisol levels obtained during ITT were significantly lower than the values obtained during both low-dose ACTH and GSTs. Peak cortisol levels obtained during the GST were lower than those found during the low dose ACTH stimulation Test. Peak GH responses were found to be higher in GST than in ITT. All three Tests had good reproducibility. Conclusions Any of 3 Tests can be used in the evaluation of the HPA axis and either GST or the ITT can be used in the evaluation of the GH-IGF-1 axis but cut-off levels for the insufficiency of HPA or GH-IGF-1 axis should be individualized for each Test.
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can basal cortisol measurement be an alternative to the Insulin Tolerance Test in the assessment of the hypothalamic pituitary adrenal axis before and after pituitary surgery
European Journal of Endocrinology, 2010Co-Authors: Zuleyha Karaca, Fatih Tanriverdi, Kursad Unluhizarci, Ahmet Selcuklu, Hulusi Atmaca, Cumali Gokce, Gulsah Elbuken, Fahrettin KelestimurAbstract:Background: The aims of this study were to evaluate the validity of preoperative basal serum cortisol levels measured in predicting preoperative adrenal insufficiency and also the validity of basal serum cortisol levels and early postoperative Insulin Tolerance Test (ITT) in predicting postoperative adrenal insufficiency. Methods: The study was prospectively designed and included 64 patients who underwent pituitary surgery for conditions other than Cushing’s disease. An ITT was performed preoperatively, on the 6th postoperative day and at the 1st postoperative month. Basal serum cortisol levels were measured on the 2nd, 3rd, 4th, 5th, and 6th postoperative days. Results: Patients with a preoperative basal cortisol level of !165 nmol/l (6 mg/dl) showed insufficient cortisol response and those with levels higher than 500 nmol/l (18 mg/dl) had sufficient cortisol response to the preoperative ITT. The positive predictive value of the ITT performed on the 6th postoperative day was 69.7%, and the negative predictive value in predicting adrenal insufficiency at the 1st postoperative month was 58%. Patients were considered to have an insufficient cortisol response to ITTat the 1st postoperative month if their basal cortisol levels were !193 nmol/l (7 mg/dl) or 220 nmol/l (8 mg/dl) or 193 nmol/l (7 mg/dl) or 165 nmol/l (6 mg/dl) or 83 nmol/l (3 mg/dl) on the 2nd‐6th postoperative days respectively. Conclusion: Serum basal cortisol levels may be used as the first-line Test in the assessment of the hypothalamic‐pituitary‐adrenal axis both preoperatively and postoperatively. Dynamic Testing should be limited to the patients with indeterminate basal cortisol levels.
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a comparison between low dose 1 µg standard dose 250 µg acth stimulation Tests and Insulin Tolerance Test in the evaluation of hypothalamo pituitary adrenal axis in primary fibromyalgia syndrome
Clinical Endocrinology, 2001Co-Authors: M Kirnap, Ramiz Colak, C Eser, O Ozsoy, Ahmet Tutus, Fahrettin KelestimurAbstract:OBJECTIVE: Primary fibromyalgia syndrome (PFS) is a nonarticular rheumatological syndrome characterized by disturbances in the hypothalamo-pituitary-adrenal (HPA) axis. The site of the defect in the HPA axis is a matter of debate. Our aim was to evaluate the HPA axis by the Insulin-Tolerance Test (ITT), standard dose (250 microg) ACTH Test (SDT) and low dose (1 microg) ACTH Test (LDT) in patients with PFS. DESIGN AND PATIENTS: Sixteen patients (13 female, three male) with PFS were included in the study. Sixteen healthy subjects (12 female, four male) served as matched controls. ACTH stimulation Tests were carried out by using 1 microg and 250 microg intravenous (i.v.) ACTH as a bolus injection after an overnight fast, and blood samples were drawn at 0, 30 and 60 min. The ITT was performed by using i.v. soluble Insulin, and serum glucose and cortisol levels were measured before and after 30, 60, 90 and 120 min. The 1 microg and 250 microg ACTH stimulation Tests and the ITT were performed consecutively. RESULTS: Peak cortisol responses to both the low dose Test (LDT) and standard dose Test (SDT) (589 +/- 100 nmol/l; 777 +/- 119 nmol/l, respectively) were lower in the PFS group than in the control group (1001 +/- 370 nmol/l; 1205 +/- 386 nmol/l, respectively) (P < 0.0001). Peak cortisol responses to ITT (730 +/- 81 nmol/l) in the PFS group were lower than in the control group (1219 +/- 412 nmol/l) (P < 0.0001). Six of the 16 patients with PFS had peak cortisol responses to LDT lower than the lowest peak cortisol response of 555 nmol/l obtained in healthy subjects after LDT. There was a significant difference between the peak cortisol responses to LDT (589 +/- 100 nmol/l) and peak cortisol responses to ITT (730 +/- 81 nmol/l) in the PFS group (P < 0.0001). Peak cortisol responses to SDT (777 +/- 119 nmol/l) were similar to peak cortisol responses to ITT (730 +/- 81 nmol/l) in the PFS group. CONCLUSION: We conclude that the perturbation of the HPA axis in PFS is characterized by underactivation of the HPA axis. Some patients with PFS may have subnormal adrenocortical function. LDT is more sensitive than SDT or ITT in the investigation of the HPA axis to determine the subnormal adrenocortical function in patients with PFS.
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a comparison between the 1 μg adrenocorticotropin acth Test the short acth 250 μg Test and the Insulin Tolerance Test in the assessment of hypothalamo pituitary adrenal axis immediately after pituitary surgery
The Journal of Clinical Endocrinology and Metabolism, 2000Co-Authors: Hatice Sebila Dokmetas, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin Kelestimur, Ramiz Colak, Fahri BayramAbstract:The short ACTH stimulation Test is an easy, reliable, and extensively used Test in the assessment of the hypothalamo-pituitary- adrenal (HPA) axis. However, its use immediately after pituitary surgery is a matter of debate. The Insulin Tolerance Test (ITT) is the gold standard in the evaluation of the HPA axis, but it is not always without side effects and may be unpleasant early after pituitary surgery. Our aim was to investigate the value of the 1-μg ACTH Test in the assessment of the HPA axis early after pituitary surgery. We also aimed to determine the value of the 1-μg and 250-μg ACTH Tests and the ITT in the estimation of HPA axis status after 3 months postoperatively. Nineteen patients subjected to pituitary tumor surgery were included in the study, and the ITT and the 1-μg and 250-μg ACTH Tests were performed between the 4th and 11th days of surgery. The Tests were repeated at the first month in 3 patients with subnormal peak cortisol responses (454, 125, and 301 nmol/L) and in 18 patients at the ...
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a comparison between the 1 μg adrenocorticotropin acth Test the short acth 250 μg Test and the Insulin Tolerance Test in the assessment of hypothalamo pituitary adrenal axis immediately after pituitary surgery
The Journal of Clinical Endocrinology and Metabolism, 2000Co-Authors: Hatice Sebila Dokmetas, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin Kelestimur, Ramiz Colak, Fahri BayramAbstract:The short ACTH stimulation Test is an easy, reliable, and extensively used Test in the assessment of the hypothalamo-pituitary-adrenal (HPA) axis. However, its use immediately after pituitary surgery is a matter of debate. The Insulin Tolerance Test (ITT) is the gold standard in the evaluation of the HPA axis, but it is not always without side effects and may be unpleasant early after pituitary surgery. Our aim was to investigate the value of the 1-microg ACTH Test in the assessment of the HPA axis early after pituitary surgery. We also aimed to determine the value of the 1-microg and 250-microg ACTH Tests and the ITT in the estimation of HPA axis status after 3 months postoperatively. Nineteen patients subjected to pituitary tumor surgery were included in the study, and the ITT and the 1-microg and 250-microg ACTH Tests were performed between the 4th and 11th days of surgery. The Tests were repeated at the first month in 3 patients with subnormal peak cortisol responses (454, 125, and 301 nmol/L) and in 18 patients at the third month postoperatively. ACTH stimulation Tests were performed by using 1 microg and 250 microg ACTH iv as a bolus injection, and blood samples were drawn at 0, 30, and 60 min for measurement of serum cortisol levels. The ITT was performed by using iv regular Insulin, and serum glucose and cortisol levels were measured. The 1-microg and 250-microg ACTH stimulation Tests and the ITT were performed consecutively. At least 48 h were allowed between each Test. A peak serum cortisol level of 550 nmol/L or greater was considered as a normal response for both the ITT and the ACTH Tests. The serum cortisol level was measured by RIA using commercial kits. Serum glucose was determined by glucose oxidase method. There were correlations between the peak cortisol response to the ITT and the 1-microg ACTH Test (r = 0.39, P or =550 nmol/L) to the 1-microg ACTH Test and five patients showed normal cortisol responses to the 250-microg ACTH Test among the six patients with subnormal cortisol responses to the ITT. Three patients with subnormal cortisol responses to ITT and baseline cortisol values less than 240 nmol/L showed normal HPA axis at the end of the first month. In the late postoperative period, at the third month, all the patients showed normal HPA axis. In the early postoperative period of pituitary surgery, the 1-microg ACTH Test results are more concordant than the 250-microg ACTH Test in comparison with the ITT. Our results also indicate that HPA axis dysfunction shown by ACTH stimulation Tests and the ITT in early postoperative period may be normalized 1-3 months after surgery. For this reason, we think that dynamic Tests including the ITT may not be useful early after pituitary surgery.
Kursad Unluhizarci - One of the best experts on this subject based on the ideXlab platform.
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a comparison of low dose acth glucagon stimulation and Insulin Tolerance Test in patients with pituitary disorders
Clinical Endocrinology, 2015Co-Authors: Yasin Simsek, Zuleyha Karaca, Fatih Tanriverdi, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin KelestimurAbstract:SummaryContext 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. Objective The primary aim of this study was to compare the ITT, low-dose ACTH and GSTs in the evaluation of HPA and GH-IGF-1 axes in patients with pituitary disorders and to evaluate the repeatability of all three Tests. Design ITT, low-dose ACTH and GSTs were performed in all 129 patients, and the Tests were repeated in 66 of these patients. Setting Erciyes University Medical School, Department of Endocrinology. Patients or Other Participants One hundred and twenty-nine adult patients (76 women, 53 men) with pituitary disorder were included in the study. Main Outcome Measure(s) The cortisol and GH responses of patients to dynamic Tests. Results Peak cortisol levels obtained during ITT were significantly lower than the values obtained during both low-dose ACTH and GSTs. Peak cortisol levels obtained during the GST were lower than those found during the low dose ACTH stimulation Test. Peak GH responses were found to be higher in GST than in ITT. All three Tests had good reproducibility. Conclusions Any of 3 Tests can be used in the evaluation of the HPA axis and either GST or the ITT can be used in the evaluation of the GH-IGF-1 axis but cut-off levels for the insufficiency of HPA or GH-IGF-1 axis should be individualized for each Test.
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can basal cortisol measurement be an alternative to the Insulin Tolerance Test in the assessment of the hypothalamic pituitary adrenal axis before and after pituitary surgery
European Journal of Endocrinology, 2010Co-Authors: Zuleyha Karaca, Fatih Tanriverdi, Kursad Unluhizarci, Ahmet Selcuklu, Hulusi Atmaca, Cumali Gokce, Gulsah Elbuken, Fahrettin KelestimurAbstract:Background: The aims of this study were to evaluate the validity of preoperative basal serum cortisol levels measured in predicting preoperative adrenal insufficiency and also the validity of basal serum cortisol levels and early postoperative Insulin Tolerance Test (ITT) in predicting postoperative adrenal insufficiency. Methods: The study was prospectively designed and included 64 patients who underwent pituitary surgery for conditions other than Cushing’s disease. An ITT was performed preoperatively, on the 6th postoperative day and at the 1st postoperative month. Basal serum cortisol levels were measured on the 2nd, 3rd, 4th, 5th, and 6th postoperative days. Results: Patients with a preoperative basal cortisol level of !165 nmol/l (6 mg/dl) showed insufficient cortisol response and those with levels higher than 500 nmol/l (18 mg/dl) had sufficient cortisol response to the preoperative ITT. The positive predictive value of the ITT performed on the 6th postoperative day was 69.7%, and the negative predictive value in predicting adrenal insufficiency at the 1st postoperative month was 58%. Patients were considered to have an insufficient cortisol response to ITTat the 1st postoperative month if their basal cortisol levels were !193 nmol/l (7 mg/dl) or 220 nmol/l (8 mg/dl) or 193 nmol/l (7 mg/dl) or 165 nmol/l (6 mg/dl) or 83 nmol/l (3 mg/dl) on the 2nd‐6th postoperative days respectively. Conclusion: Serum basal cortisol levels may be used as the first-line Test in the assessment of the hypothalamic‐pituitary‐adrenal axis both preoperatively and postoperatively. Dynamic Testing should be limited to the patients with indeterminate basal cortisol levels.
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a comparison between the 1 μg adrenocorticotropin acth Test the short acth 250 μg Test and the Insulin Tolerance Test in the assessment of hypothalamo pituitary adrenal axis immediately after pituitary surgery
The Journal of Clinical Endocrinology and Metabolism, 2000Co-Authors: Hatice Sebila Dokmetas, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin Kelestimur, Ramiz Colak, Fahri BayramAbstract:The short ACTH stimulation Test is an easy, reliable, and extensively used Test in the assessment of the hypothalamo-pituitary- adrenal (HPA) axis. However, its use immediately after pituitary surgery is a matter of debate. The Insulin Tolerance Test (ITT) is the gold standard in the evaluation of the HPA axis, but it is not always without side effects and may be unpleasant early after pituitary surgery. Our aim was to investigate the value of the 1-μg ACTH Test in the assessment of the HPA axis early after pituitary surgery. We also aimed to determine the value of the 1-μg and 250-μg ACTH Tests and the ITT in the estimation of HPA axis status after 3 months postoperatively. Nineteen patients subjected to pituitary tumor surgery were included in the study, and the ITT and the 1-μg and 250-μg ACTH Tests were performed between the 4th and 11th days of surgery. The Tests were repeated at the first month in 3 patients with subnormal peak cortisol responses (454, 125, and 301 nmol/L) and in 18 patients at the ...
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a comparison between the 1 μg adrenocorticotropin acth Test the short acth 250 μg Test and the Insulin Tolerance Test in the assessment of hypothalamo pituitary adrenal axis immediately after pituitary surgery
The Journal of Clinical Endocrinology and Metabolism, 2000Co-Authors: Hatice Sebila Dokmetas, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin Kelestimur, Ramiz Colak, Fahri BayramAbstract:The short ACTH stimulation Test is an easy, reliable, and extensively used Test in the assessment of the hypothalamo-pituitary-adrenal (HPA) axis. However, its use immediately after pituitary surgery is a matter of debate. The Insulin Tolerance Test (ITT) is the gold standard in the evaluation of the HPA axis, but it is not always without side effects and may be unpleasant early after pituitary surgery. Our aim was to investigate the value of the 1-microg ACTH Test in the assessment of the HPA axis early after pituitary surgery. We also aimed to determine the value of the 1-microg and 250-microg ACTH Tests and the ITT in the estimation of HPA axis status after 3 months postoperatively. Nineteen patients subjected to pituitary tumor surgery were included in the study, and the ITT and the 1-microg and 250-microg ACTH Tests were performed between the 4th and 11th days of surgery. The Tests were repeated at the first month in 3 patients with subnormal peak cortisol responses (454, 125, and 301 nmol/L) and in 18 patients at the third month postoperatively. ACTH stimulation Tests were performed by using 1 microg and 250 microg ACTH iv as a bolus injection, and blood samples were drawn at 0, 30, and 60 min for measurement of serum cortisol levels. The ITT was performed by using iv regular Insulin, and serum glucose and cortisol levels were measured. The 1-microg and 250-microg ACTH stimulation Tests and the ITT were performed consecutively. At least 48 h were allowed between each Test. A peak serum cortisol level of 550 nmol/L or greater was considered as a normal response for both the ITT and the ACTH Tests. The serum cortisol level was measured by RIA using commercial kits. Serum glucose was determined by glucose oxidase method. There were correlations between the peak cortisol response to the ITT and the 1-microg ACTH Test (r = 0.39, P or =550 nmol/L) to the 1-microg ACTH Test and five patients showed normal cortisol responses to the 250-microg ACTH Test among the six patients with subnormal cortisol responses to the ITT. Three patients with subnormal cortisol responses to ITT and baseline cortisol values less than 240 nmol/L showed normal HPA axis at the end of the first month. In the late postoperative period, at the third month, all the patients showed normal HPA axis. In the early postoperative period of pituitary surgery, the 1-microg ACTH Test results are more concordant than the 250-microg ACTH Test in comparison with the ITT. Our results also indicate that HPA axis dysfunction shown by ACTH stimulation Tests and the ITT in early postoperative period may be normalized 1-3 months after surgery. For this reason, we think that dynamic Tests including the ITT may not be useful early after pituitary surgery.
Ahmet Selcuklu - One of the best experts on this subject based on the ideXlab platform.
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a comparison of low dose acth glucagon stimulation and Insulin Tolerance Test in patients with pituitary disorders
Clinical Endocrinology, 2015Co-Authors: Yasin Simsek, Zuleyha Karaca, Fatih Tanriverdi, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin KelestimurAbstract:SummaryContext 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. Objective The primary aim of this study was to compare the ITT, low-dose ACTH and GSTs in the evaluation of HPA and GH-IGF-1 axes in patients with pituitary disorders and to evaluate the repeatability of all three Tests. Design ITT, low-dose ACTH and GSTs were performed in all 129 patients, and the Tests were repeated in 66 of these patients. Setting Erciyes University Medical School, Department of Endocrinology. Patients or Other Participants One hundred and twenty-nine adult patients (76 women, 53 men) with pituitary disorder were included in the study. Main Outcome Measure(s) The cortisol and GH responses of patients to dynamic Tests. Results Peak cortisol levels obtained during ITT were significantly lower than the values obtained during both low-dose ACTH and GSTs. Peak cortisol levels obtained during the GST were lower than those found during the low dose ACTH stimulation Test. Peak GH responses were found to be higher in GST than in ITT. All three Tests had good reproducibility. Conclusions Any of 3 Tests can be used in the evaluation of the HPA axis and either GST or the ITT can be used in the evaluation of the GH-IGF-1 axis but cut-off levels for the insufficiency of HPA or GH-IGF-1 axis should be individualized for each Test.
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can basal cortisol measurement be an alternative to the Insulin Tolerance Test in the assessment of the hypothalamic pituitary adrenal axis before and after pituitary surgery
European Journal of Endocrinology, 2010Co-Authors: Zuleyha Karaca, Fatih Tanriverdi, Kursad Unluhizarci, Ahmet Selcuklu, Hulusi Atmaca, Cumali Gokce, Gulsah Elbuken, Fahrettin KelestimurAbstract:Background: The aims of this study were to evaluate the validity of preoperative basal serum cortisol levels measured in predicting preoperative adrenal insufficiency and also the validity of basal serum cortisol levels and early postoperative Insulin Tolerance Test (ITT) in predicting postoperative adrenal insufficiency. Methods: The study was prospectively designed and included 64 patients who underwent pituitary surgery for conditions other than Cushing’s disease. An ITT was performed preoperatively, on the 6th postoperative day and at the 1st postoperative month. Basal serum cortisol levels were measured on the 2nd, 3rd, 4th, 5th, and 6th postoperative days. Results: Patients with a preoperative basal cortisol level of !165 nmol/l (6 mg/dl) showed insufficient cortisol response and those with levels higher than 500 nmol/l (18 mg/dl) had sufficient cortisol response to the preoperative ITT. The positive predictive value of the ITT performed on the 6th postoperative day was 69.7%, and the negative predictive value in predicting adrenal insufficiency at the 1st postoperative month was 58%. Patients were considered to have an insufficient cortisol response to ITTat the 1st postoperative month if their basal cortisol levels were !193 nmol/l (7 mg/dl) or 220 nmol/l (8 mg/dl) or 193 nmol/l (7 mg/dl) or 165 nmol/l (6 mg/dl) or 83 nmol/l (3 mg/dl) on the 2nd‐6th postoperative days respectively. Conclusion: Serum basal cortisol levels may be used as the first-line Test in the assessment of the hypothalamic‐pituitary‐adrenal axis both preoperatively and postoperatively. Dynamic Testing should be limited to the patients with indeterminate basal cortisol levels.
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a comparison between the 1 μg adrenocorticotropin acth Test the short acth 250 μg Test and the Insulin Tolerance Test in the assessment of hypothalamo pituitary adrenal axis immediately after pituitary surgery
The Journal of Clinical Endocrinology and Metabolism, 2000Co-Authors: Hatice Sebila Dokmetas, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin Kelestimur, Ramiz Colak, Fahri BayramAbstract:The short ACTH stimulation Test is an easy, reliable, and extensively used Test in the assessment of the hypothalamo-pituitary- adrenal (HPA) axis. However, its use immediately after pituitary surgery is a matter of debate. The Insulin Tolerance Test (ITT) is the gold standard in the evaluation of the HPA axis, but it is not always without side effects and may be unpleasant early after pituitary surgery. Our aim was to investigate the value of the 1-μg ACTH Test in the assessment of the HPA axis early after pituitary surgery. We also aimed to determine the value of the 1-μg and 250-μg ACTH Tests and the ITT in the estimation of HPA axis status after 3 months postoperatively. Nineteen patients subjected to pituitary tumor surgery were included in the study, and the ITT and the 1-μg and 250-μg ACTH Tests were performed between the 4th and 11th days of surgery. The Tests were repeated at the first month in 3 patients with subnormal peak cortisol responses (454, 125, and 301 nmol/L) and in 18 patients at the ...
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a comparison between the 1 μg adrenocorticotropin acth Test the short acth 250 μg Test and the Insulin Tolerance Test in the assessment of hypothalamo pituitary adrenal axis immediately after pituitary surgery
The Journal of Clinical Endocrinology and Metabolism, 2000Co-Authors: Hatice Sebila Dokmetas, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin Kelestimur, Ramiz Colak, Fahri BayramAbstract:The short ACTH stimulation Test is an easy, reliable, and extensively used Test in the assessment of the hypothalamo-pituitary-adrenal (HPA) axis. However, its use immediately after pituitary surgery is a matter of debate. The Insulin Tolerance Test (ITT) is the gold standard in the evaluation of the HPA axis, but it is not always without side effects and may be unpleasant early after pituitary surgery. Our aim was to investigate the value of the 1-microg ACTH Test in the assessment of the HPA axis early after pituitary surgery. We also aimed to determine the value of the 1-microg and 250-microg ACTH Tests and the ITT in the estimation of HPA axis status after 3 months postoperatively. Nineteen patients subjected to pituitary tumor surgery were included in the study, and the ITT and the 1-microg and 250-microg ACTH Tests were performed between the 4th and 11th days of surgery. The Tests were repeated at the first month in 3 patients with subnormal peak cortisol responses (454, 125, and 301 nmol/L) and in 18 patients at the third month postoperatively. ACTH stimulation Tests were performed by using 1 microg and 250 microg ACTH iv as a bolus injection, and blood samples were drawn at 0, 30, and 60 min for measurement of serum cortisol levels. The ITT was performed by using iv regular Insulin, and serum glucose and cortisol levels were measured. The 1-microg and 250-microg ACTH stimulation Tests and the ITT were performed consecutively. At least 48 h were allowed between each Test. A peak serum cortisol level of 550 nmol/L or greater was considered as a normal response for both the ITT and the ACTH Tests. The serum cortisol level was measured by RIA using commercial kits. Serum glucose was determined by glucose oxidase method. There were correlations between the peak cortisol response to the ITT and the 1-microg ACTH Test (r = 0.39, P or =550 nmol/L) to the 1-microg ACTH Test and five patients showed normal cortisol responses to the 250-microg ACTH Test among the six patients with subnormal cortisol responses to the ITT. Three patients with subnormal cortisol responses to ITT and baseline cortisol values less than 240 nmol/L showed normal HPA axis at the end of the first month. In the late postoperative period, at the third month, all the patients showed normal HPA axis. In the early postoperative period of pituitary surgery, the 1-microg ACTH Test results are more concordant than the 250-microg ACTH Test in comparison with the ITT. Our results also indicate that HPA axis dysfunction shown by ACTH stimulation Tests and the ITT in early postoperative period may be normalized 1-3 months after surgery. For this reason, we think that dynamic Tests including the ITT may not be useful early after pituitary surgery.
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a comparison between the 1 μg adrenocorticotropin acth Test the short acth 250 μg Test and the Insulin Tolerance Test in the assessment of hypothalamo pituitary adrenal axis immediately after pituitary surgery
The Journal of Clinical Endocrinology and Metabolism, 2000Co-Authors: Hatice Sebila Dokmetas, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin Kelestimur, Ramiz Colak, Fahri BayramAbstract:The short ACTH stimulation Test is an easy, reliable, and extensively used Test in the assessment of the hypothalamo-pituitary- adrenal (HPA) axis. However, its use immediately after pituitary surgery is a matter of debate. The Insulin Tolerance Test (ITT) is the gold standard in the evaluation of the HPA axis, but it is not always without side effects and may be unpleasant early after pituitary surgery. Our aim was to investigate the value of the 1-μg ACTH Test in the assessment of the HPA axis early after pituitary surgery. We also aimed to determine the value of the 1-μg and 250-μg ACTH Tests and the ITT in the estimation of HPA axis status after 3 months postoperatively. Nineteen patients subjected to pituitary tumor surgery were included in the study, and the ITT and the 1-μg and 250-μg ACTH Tests were performed between the 4th and 11th days of surgery. The Tests were repeated at the first month in 3 patients with subnormal peak cortisol responses (454, 125, and 301 nmol/L) and in 18 patients at the ...
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a comparison between the 1 μg adrenocorticotropin acth Test the short acth 250 μg Test and the Insulin Tolerance Test in the assessment of hypothalamo pituitary adrenal axis immediately after pituitary surgery
The Journal of Clinical Endocrinology and Metabolism, 2000Co-Authors: Hatice Sebila Dokmetas, Kursad Unluhizarci, Ahmet Selcuklu, Fahrettin Kelestimur, Ramiz Colak, Fahri BayramAbstract:The short ACTH stimulation Test is an easy, reliable, and extensively used Test in the assessment of the hypothalamo-pituitary-adrenal (HPA) axis. However, its use immediately after pituitary surgery is a matter of debate. The Insulin Tolerance Test (ITT) is the gold standard in the evaluation of the HPA axis, but it is not always without side effects and may be unpleasant early after pituitary surgery. Our aim was to investigate the value of the 1-microg ACTH Test in the assessment of the HPA axis early after pituitary surgery. We also aimed to determine the value of the 1-microg and 250-microg ACTH Tests and the ITT in the estimation of HPA axis status after 3 months postoperatively. Nineteen patients subjected to pituitary tumor surgery were included in the study, and the ITT and the 1-microg and 250-microg ACTH Tests were performed between the 4th and 11th days of surgery. The Tests were repeated at the first month in 3 patients with subnormal peak cortisol responses (454, 125, and 301 nmol/L) and in 18 patients at the third month postoperatively. ACTH stimulation Tests were performed by using 1 microg and 250 microg ACTH iv as a bolus injection, and blood samples were drawn at 0, 30, and 60 min for measurement of serum cortisol levels. The ITT was performed by using iv regular Insulin, and serum glucose and cortisol levels were measured. The 1-microg and 250-microg ACTH stimulation Tests and the ITT were performed consecutively. At least 48 h were allowed between each Test. A peak serum cortisol level of 550 nmol/L or greater was considered as a normal response for both the ITT and the ACTH Tests. The serum cortisol level was measured by RIA using commercial kits. Serum glucose was determined by glucose oxidase method. There were correlations between the peak cortisol response to the ITT and the 1-microg ACTH Test (r = 0.39, P or =550 nmol/L) to the 1-microg ACTH Test and five patients showed normal cortisol responses to the 250-microg ACTH Test among the six patients with subnormal cortisol responses to the ITT. Three patients with subnormal cortisol responses to ITT and baseline cortisol values less than 240 nmol/L showed normal HPA axis at the end of the first month. In the late postoperative period, at the third month, all the patients showed normal HPA axis. In the early postoperative period of pituitary surgery, the 1-microg ACTH Test results are more concordant than the 250-microg ACTH Test in comparison with the ITT. Our results also indicate that HPA axis dysfunction shown by ACTH stimulation Tests and the ITT in early postoperative period may be normalized 1-3 months after surgery. For this reason, we think that dynamic Tests including the ITT may not be useful early after pituitary surgery.