Betul Hatipoglu

Diagnostic Characteristics of Late-Night Salivary Cortisol Using Liquid Chromatography-Tandem Mass Spectrometry

OBJECTIVE The objective of the study was to describe the diagnostic performance of a commercially available late-night salivary cortisol (NSC) assay using liquid chromatography tandem mass spectrometry. METHODS We retrospectively identified 90 patients who had one or more NSC determinations: 52 patients in whom Cushing syndrome (CS) was excluded or could not be confirmed [group 1 (G1)] and 38 patients in whom CS was confirmed [group 2 (G2)]. Eighteen healthy volunteers served as controls. RESULTS Baseline demographics in all groups were similar with regards to age, ethnicity, gender, and body mass index. NSC levels [median (range)] were higher in G2, 381 (64-13,500) ng/dl [10.51 (1.77-372.46) nmol/liter], compared with controls, 19.3 (2.1-416) ng/dl [0.53 (0.06-11.48) nmol/liter], and G1, 26 (4-176) ng/dl [0.72 (0.11-4.86) nmol/liter, P < 0.001]. The highest combined sensitivity (92%) and specificity (92%) was achieved at a cut point of 107 ng/dl (2.95 nmol/liter). Two or more NSCs were done in 32 of 52 G1 and 31 of 38 G2 patients. In G1 eight of 32 (25%) had at least one elevated [>100 ng/dl (2.76 nmol/liter)] NSC including two in whom both NSCs were elevated. In contrast, four of 31 (13%) in G2 had at least one normal NSC including one with four of five normal NSC values. None of the patients with CS had a NSC less than 60 ng/dl (<1.66 nmol/liter). Comparing G1 and G2, obtaining more than one saliva sample did not improve the diagnostic accuracy of NSC measurement (P = 0.64). CONCLUSION The liquid chromatography tandem mass spectrometry assay to measure NSC is a simple and reliable test to screen patients suspected to have CS. Clinicians should be aware of appropriate cutoff values for proper interpretation of NSC and use additional tests when necessary.

Pregnancy and acromegaly: a review

To review the literature regarding the diagnosis and management of acromegaly during pregnancy. A systematic literature search was performed using MEDLINE including hand-searching reference lists from original articles. The diagnosis of acromegaly during pregnancy is made difficult due to the physiologic changes in pituitary GH secretion and IGF-1 production resulting from placental GH secretion and the inability of commercial assays to discriminate between pituitary and placental GH. Most patients with acromegaly during pregnancy do not have an increase in tumor size, metabolic complications are uncommon, and neonatal outcome is largely unaffected. IGF-1 levels tend to be stable in such patients possibly due to the high estrogen levels causing GH resistance. Dopamine agonists, somatostatin analogues, and a GH receptor antagonist have been reported to be safe during pregnancy. Patients with visual field defects should be considered for surgery, but in most cases this can be safely postponed until after delivery. Overall, pregnancy in acromegaly is uneventful and newborns unaffected. Dopamine agonists and somatostatin analogues have not been associated with major adverse effects to the fetus; however, more data are needed to validate their safety.

Reduction in Carotid Intima-Media Thickness After Pancreatic Islet Transplantation in Patients With Type 1 Diabetes

OBJECTIVE Determine the impact of islet transplantation on carotid intima-media thickness (CIMT), a marker for atherosclerosis, in type 1 diabetes without kidney disease. RESEARCH DESIGN AND METHODS Consecutive case series of 15 adults (mean age [SD], 49 years [10 years]; 87% female) with type 1 diabetes for ≥5 years (mean duration [SD], 30 years [12 years]; mean HbA1c [SD], 7.2% [0.9%]), without kidney disease, presenting with severe hypoglycemic unawareness to undergo allogeneic pancreatic islet transplant(s) (one to three each) in a phase 1/2 and 3 clinical trial. Current follow-up ranges from 1 to 5 years (2005–2011). CIMT of the common and internal carotid arteries was measured before and every 12–16 months after the first transplant (two to six CIMTs each) by one ultrasonographer and one blinded reader. CIMT was analyzed as change from baseline to 12- and 50-month follow-up; a combined CIMT score was calculated as the sum of the standardized IMT scores (SD units [SDs]) of both arteries. RESULTS All patients achieved insulin independence after one to three transplants. CIMT decreased at 12 months (n = 15) for the common carotid (−0.058 mm; P = 0.006) and combined score (−1.28 SDs; P = 0.004). In those with 50-month follow-up (n = 7), the decrease in the combined score continued from 12 (−1.59 SDs; P = 0.04) to 50 months (−0.77 SDs; P = 0.04). During follow-up, the decreasing slope of change in CIMT was associated with decreasing slopes of change in HbA1c, lipoproteins, and cardiovascular/inflammatory markers. CONCLUSIONS Islet transplantation may ameliorate diabetes-related atherosclerosis through improved glycemic control consequent to restoring endogenous insulin secretion, and optimal lipid management posttransplant also contributes.

Cushing's syndrome

Cushings syndrome (CS) results from prolonged exposure to elevated endogenous cortisol. Majority of cases are caused by ACTH, pituitary, or ectopic origin. Primary adrenal hypersecretion is 15–20% caused by adenomas, carcinomas (ACC), and rarely by nodular adrenocortical disease. CS presents with all typical features. Commonly recommended initial testing are urinary free cortisol, late‐night salivary cortisol, and 1‐mg overnight dexamethasone suppression test (DST). Imaging is the key to diagnosis. CS continues to pose diagnostic and therapeutic challenges; life‐long follow‐up is mandatory. J. Surg. Oncol. 2012; 106:565–571.

Prolactin measurement during inferior petrosal sinus sampling improves the localization of pituitary adenomas in Cushing's disease

Inferior petrosal sinus sampling (IPSS) distinguishes pituitary‐dependent Cushings disease (CD) from ectopic ACTH syndrome with a high degree of certainty, but has not been reliable in predicting the location of an adenoma within the pituitary gland. We investigated whether prolactin measurements during IPSS would improve pituitary tumour localization.

Serum IGF-1 in the diagnosis of acromegaly and the profile of patients with elevated IGF-1 but normal glucose-suppressed growth hormone.

OBJECTIVE To report the utility of insulin-like growth factor-1 (IGF-1) as a single biomarker for establishing the diagnosis of acromegaly and to examine the clinical and biochemical profile of patients with an elevated IGF-1 in whom a diagnosis of acromegaly could not be confirmed by means of the oral glucose tolerance test (OGTT). METHODS Between the years 1999 and 2010, we identified 101 patients who underwent pituitary surgery and had histologically proven somatotroph adenomas (Group 1, Gr 1). We selected 149 patients with non-growth hormone (GH) secreting pituitary macroadenomas (Gr 2, n = 97) and microadenomas (Gr 3, n = 52) to serve as control subjects. In addition, we identified 34 patients with elevated IGF-1values in whom acromegaly could not subsequently be proven by the OGTT (Gr 4). RESULTS IGF-1 was elevated in all patients with acromegaly prior to therapy with a median (range) standard deviation score (SDS) of +9.52 (+2.34 to +9.2), compared to SDS -1.46 (-2.91 to +2.17) and -1.22 (-2.8 to +1.58) in Gr 2 and 3, respectively (P<0.001). IGF-1 SDS values were +3.28 (+2.05 to +6.1), and IGF-1 was less than twice the upper limit of normal in all patients in Gr 4. OGTT was performed in 51 of the 101 acromegalic patients. The nadir GH in these patients was 4.01 (0.2 to 46.7) in comparison with 0.2 (<0.05 to 0.6) in Gr 4 (P<0.001). CONCLUSION Elevated IGF-1 levels, alone, are sufficient to establish a diagnosis of acromegaly in the majority of clinically suspected cases. The OGTT may be useful to obtain corroborative evidence when there is modest elevation of IGF-1 with absent or equivocal clinical features.

Hypothyroidism as a cause of hyponatremia: fact or fiction?

OBJECTIVE To illustrate that severe primary hypothyroidism alone may not be enough to cause hyponatremia in the otherwise healthy ambulatory patient. METHODS A retrospective chart review was conducted using an academic health center enterprise-wide electronic health record to identify 10 patients with primary hypothyroidism and same-day serum thyroid-stimulating hormone (TSH), sodium, creatinine, and calculated glomerular filtration rate (GFR). Same-day free triiodothyronine or free thyroxine was also recorded if tested. Patients were included in our case series if they met the following inclusion criteria: TSH level >100 μU/mL and same-day sodium and creatinine levels. All laboratory tests were collected on an outpatient basis. RESULTS The 10 subjects (2 men and 8 women) were ages 19 to 97 years (median, 51.5 years). Median TSH was 193 μU/mL (range, 104.2 to 515.6 μU/mL; normal, 0.40 to 5.50 μU/mL) with median sodium of 138 mmol/L (range, 136 to 142 mmol/L; normal, 135 to 146 mmol/L). The lowest sodium was 136 mmol/L with concurrent TSH of 469.7 μU/mL, free triiodothyronine of 1.0 pg/mL (normal, 1.8 to 4.6 pg/mL), and free thyroxine of 0.2 ng/dL (normal, 0.7 to 1.8 ng/dL). Median GFR was 67.5 mL/min/1.73 m2 (range, 44 to 114 mL/min/1.73 m2; normal, 90 to 120 mL/min/1.73 m2). CONCLUSION In our small series of patients with extreme TSH elevations, none had a serum sodium level below normal (<135 mmol/L), even in the presence of a reduced GFR. Hyponatremia can be a common occurrence in hospitalized and/or chronically ill patients; however, in an otherwise relatively healthy ambulatory patient, hypothyroidism, even when severely undertreated, may be a less clinically relevant cause of hyponatremia.

A Rare Corticotroph-Secreting Tumor with Coexisting Prolactin and Growth Hormone Staining Cells

Pituitary adenomas can express and secrete different hormones. Expression of pituitary hormones in nonneoplastic pituitary cells is regulated by different transcription factors. Some pituitary adenomas show plurihormonal expression. The most commonly reported plurihormonal adenomas are composed of somatotrophs, lactotrophs, thyrotrophs and gonadotrophs. Pituitary adenomas composed of both corticotroph and somatolactotroph secreting cells are not common because transcription factors regulating the expression of these hormones are different. We report a rare case of pituitary adenoma with concomitant corticotroph, prolactin, and growth hormone staining cells, review literature on similar cases, and discuss possible biological mechanisms underlying these plurihormonal tumors.

Hyponatremia and the Thyroid: Causality or Association?

Thyroid disorders, particularly hypothyroidism, have historically been implicated in the development of serum hyponatremia. However, in more recent years, this paradigm has been challenged, and it has been suggested that the link between hypothyroidism and hyponatremia may merely be an association. This review will focus on the thyroid and its link with serum hyponatremia, and review the available literature on the topic.

Spontaneous cerebrospinal fluid rhinorrhea as the initial presentation of growth hormone–secreting pituitary adenoma

Patients with acromegaly usually present with characteristic clinical features or comorbidities associated with excess insulinlike growth factor 1 (IGF-1)/growth hormone (GH) or may come to medical attention secondary to mass effects causing visual field distortions. Herein, we report a case of spontaneous cerebrospinal fluid (CSF) rhinorrhea as the presenting symptom of acromegaly. A 68-year-old man presented to an outside facility with a 2-day history of headache associated with nausea, vomiting, dizziness, and clear nasal discharge and underwent 2 attempted repairs of a sphenoid sinus CSF leak. Examination on admission to our hospital was significant for fluctuating level of consciousness. Subsequently, subtle coarse facial features were appreciated. Pituitary function testing showed thyrotropin and gonadotropin deficiencies along with an elevated age- and sex-matched IGF-1 of 285 (normal level, 59-225 ng/mL). Nadir GH during oral glucose tolerance test was 5.5 ng/mL and confirmed the diagnosis of acromegaly. Magnetic resonance imaging showed pneumocephalus, an enlarged sella with an elongated pituitary stalk, and partial erosion of the anterior wall of the sphenoid sinus. A distinct adenoma could not be identified. An endoscopic, transnasal, transsphenoidal exploration and biopsy with multilayered skull base reconstruction were performed. Histologic examination of the biopsy contents was consistent with a GH-producing adenoma. Postoperatively, the patients fluctuating level of consciousness improved and returned to baseline after his successful skull base repair. During the follow-up period, he had an IGF-1 of 713 ng/mL and started treatment with a somatostatin analogue. To our knowledge, this is the first reported case of a GH-producing pituitary adenoma presenting with spontaneous CSF rhinorrhea. Pituitary adenomas should be considered in the differential diagnosis of patients presenting with spontaneous CSF rhinorrhea with abnormal sellar image, and these patients should undergo a thorough hormonal evaluation.