Desmopressin is Promising Alternative in Diagnosing Cushing’s Disease

Bilateral inferior petrosal sinus sampling (IPSS) — a procedure that uses desmopressin to determine levels of ACTH hormone from veins that drain from the pituitary gland, is a sensitive way to diagnose patients with Cushing’s disease and find tumors, a Chinese study shows.

The study, “Tumour Lateralization in Cushing’s disease by Inferior Petrosal Sinus Sampling with desmopressin,” appeared in the journal Clinical Endocrinology.

Cushing’s disease is characterized by excessive production of the adrenocorticotropin hormone (ACTH) caused by a tumor in the pituitary gland. ACTH is the hormone that causes the adrenal glands to produce cortisol.

Currently, pituitary imaging is insufficient to confirm a Cushing’s diagnosis. This is because 70 percent of pituitary adenomas in Cushing’s are microadenomas, which are physically very small. As a result, 40 percent of Cushing’s patients are reported as being healthy.

This means that a Cushing’s diagnosis requires a combination of techniques including clinical symptoms, imaging methods and endocrinological assays that include measures of serum cortisol and ACTH levels.

IPSS determines ACTH levels from veins that drain from the pituitary gland. ACTH levels are then compared to ACTH levels in blood. Higher levels in the pituitary gland indicate a pituitary tumor.

IPSS can also be used to determine tumor lateralization, which refers to which side of the pituitary gland the tumor is located on. The test is 69 percent accurate.

Doctors administer IPSS along with corticotropin-releasing hormone (CRH) stimulation. IPSS with CRH is considered the gold standard for preoperative diagnosis of Cushing’s, with a diagnostic sensitivity (or true positive rate) of 95 percent and specificity (or true negative rate) of 90 to 95 percent. Unfortunately, the high cost and limited availability of CRH make it impractical for many patients.

Desmopressin has been used to replace CRH to stimulate ACTH secretion for IPSS, and prior studies have shown that desmopressin’s sensitivity is comparable to that of CRH.

Researchers at Peking Union Medical College in Beijing conducted a retrospective analysis of their experience using desmopressin-stimulated IPSS to determine its diagnostic value for Cushing’s and its predictive value for tumor lateralization.

Researchers analyzed 91 Cushing’s patients who either had negative findings on the MRI imaging of the pituitary or negative high-dose dexamethasone suppression tests, which is another method of evaluation. All patients underwent IPSS with desmopressin, followed by pituitary surgery to extract the tumor.

Of the 91 patients tested, 90 patients had confirmed Cushing’s. And of these, 89 had positive IPSS findings, which led to a sensitivity of 98.9 percent for this test. One patient out of 91 who did not have Cushing’s also underwent this test, which led to a negative IPSS result and a specificity of 100 percent.

Researchers also determined tumor lateralization in patients who were ultimately diagnosed with Cushing’s and underwent surgery. Results of the IPSS showed a 72.5 percent concordance between the results from the IPSS and the surgery.

Therefore, IPSS with desmopressin is a comparable approach to IPSS with CRH for the diagnosis of Cushing’s. It also demonstrates moderate accuracy in determining the location of tumors.

“Like many medical centers in China, we currently have no supply of CRH, while desmopressin is readily available,” researchers concluded. “Moreover, desmopressin is cheaper than CRH. As our data and other studies indicate, IPSS with desmopressin yielded comparable outcomes to IPSS with CRH. Therefore, desmopressin-stimulated IPSS might serve as a possible alternative to CRH-stimulated IPSS.”

From https://cushingsdiseasenews.com/2017/11/14/ipss-desmopressin-alternative-method-diagnosis-cushings-disease/

Study Highlights Importance of Clinical Follow-Up in Cushing’s Patients After Adenoma Removal

A rare case of Cushing’s syndrome (CS) in a 17-year-old patient with multiple pituitary adenomas highlights the importance of clinical follow-up in order to determine the best treatment options for patients.

The study, “A rare case of multiple pituitary adenomas in an adolescent Cushing disease presenting as a vertebral compression fracture,” was published in the journal Annals of Pediatric Endocrinology and Metabolism

CS is a very rare disease with an incidence of 0.7-2.4 cases per million, per year. It is caused by exposure to very high levels of the hormone cortisol. In children, the most common symptom is weight gain without height gain. In some rare cases, tumors known as multiple pituitary adenomas (MPAs) appear, and patients have elevated levels of adrenocorticotropic hormone (ACTH). Surgical removal through transsphenoidal surgery (TSS) is considered the best treatment, and the first TSS has a success rate of more than 90%.

However, since 15% of patients have a recurrence, ongoing monitoring and follow-up after TSS are important. The importance of this follow-up care is highlighted in a recent case report.

The study described the case of a 17-year-old male adolescent who was 149.5 cm tall (4’9″) and weighed 63.6 kg (140 lbs). The patient was referred to a hospital for the evaluation of a vertebral compression fracture and obesity. Over four years, the patient gained 23 kg (51 lbs) without an increase in height. Despite showing many of the features of CS, this patient had not been previously diagnosed with CS.

He had high levels of ACTH and cortisol, and an MRI suggested the presence of an 8-mm (0.8 cm) micro-adenoma. After TSS, the patient’s morning ACTH and cortisol levels were reduced, and a persistent headache had improved. But there was no reduction in weight.

Three months after the TSS, the patient’s body mass index did not show improvement, and both cortisol and ACTH levels were elevated again. MRI revealed a new 9 mm (0.9 cm) micro-adenoma, which was removed with a second TSS. However, cortisol and ACHT remained elevated after the second surgery, with no evidence of a pituitary tumor in MRI scans.

Researchers recommended additional options, such as total removal of the pituitary gland, radiotherapy, or removal of both adrenal glands, options that the patient and his family declined. He continued to receive treatment for osteoporosis, hypertension, and increased lipid levels.

“In conclusion, we reported the clinical course of Cushing disease with 2 distinct pituitary adenomas. Since there is no consensus as to the best treatment for relapsing or persistent Cushing disease and since only a few cases of MPA among pediatric Cushing disease have been reported, a close followup of tumor status, severity of hypercortisolism, and patients’ perspectives are the major parameters used to determine the best treatment option for each patient. In addition, early recognition and diagnosis of pediatric Cushing disease would lead to earlier recovery, improved growth, and better quality of life,” the researchers wrote.

From https://cushingsdiseasenews.com/2017/10/27/cushings-disease-rare-case-report-highlights-importance-early-diagnosis-follow-up-care/

Increase in Glucose Uptake by Cushing’s Disease-associated Tumors Could Improve Early Detection

An increase in glucose uptake by Cushing’s disease-associated pituitary tumors could improve their detection, new research shows.

The study, “Corticotropin releasing hormone can selectively stimulate glucose uptake in corticotropinoma via glucose transporter 1,” appeared in the journal Molecular and Cellular Endocrinology.

The study’s senior author was Dr. Prashant Chittiboina, MD, from the Department of Neurosurgery, Wexner Medical Center, The Ohio State University, in Columbus, Ohio.

Microadenomas – tumors in the pituitary gland measuring less than 10 mm in diameter – that release corticotropin, or corticotropinomas, can lead to Cushing’s disease. The presurgical detection of these microadenomas could improve surgical outcomes in patients with Cushing’s.

But current tumor visualization methodologies – magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) – failed to detect a significant percentage of pituitary microadenomas.

Stimulation with corticotropin-releasing hormone (CRH), which increases glucose uptake, has been suggested as a method of increasing the detection of adenomas with 18F-FDG PET, by augmenting the uptake of 18F-FDG – a glucose analog.

However, previous studies aiming to validate this idea have failed, leading the research team to hypothesize that it may be due to a delayed elevation in glucose uptake in corticotropinomas.

The scientists used clinical data to determine the effectiveness of CRH in improving the detection of corticotropinomas with 18F-FDG PET in Cushing’s disease.

They found that CRH increased glucose uptake in human and mouse tumor cells, but not in healthy mouse or human pituitary cells that produce the adrenocorticotropic hormone (ACTH). Exposure to CRH increased glucose uptake in mouse tumor cells, with a maximal effect at four hours after stimulation.

Similarly, the glucose transporter GLUT1, which is located at the cell membrane, was increased two hours after stimulation, as was GLUT1-mediated glucose transport.

These findings indicate a potential mechanism linking CRH exposure to augmented glucose uptake through GLUT1. Expectedly, the inhibition of glucose transport with fasentin suppressed glucose uptake.

The researchers consistently observed exaggerated evidence of GLUT1 in human corticotropinomas. In addition, human corticotroph tumor cells showed an increased breakdown of glucose, which indicates that, unlike healthy cells, pituitary adenomas use glucose as their primary source of energy.

Overall, the study shows that corticotropin-releasing hormone (CRH) leads to a specific and delayed increase in glucose uptake in tumor corticotrophs.

“Taken together, these novel findings support the potential use of delayed 18F-FDG PET imaging following CRH stimulation to improve microadenoma detection in [Cushing’s disease],” researchers wrote. The scientists are now conducting a clinical trial to further explore this promising finding.

From https://cushingsdiseasenews.com/2017/10/12/glucose-uptake-in-cushings-disease-could-improve-presurgical-tumor-detection/

Basal Cortisol Elevated in Patients with ACTH-Staining Pituitary Macroadenoma

Preoperative identification of patients with silent adrenocorticotrophic hormone-secreting tumors could potentially change the approach to management. A new study aimed to determine whether a preoperative adrenocorticotrophic hormone stimulation test for evaluation of nonfunctional pituitary macroadenoma could aid in identifying adrenocorticotrophic hormone-staining pathology yielded large variability and did not allow clinical utility.

Thus, researchers concluded that larger, multicenter research is needed to determine whether this test can be useful.

“As ACTH stimulation tests are performed routinely when evaluating macroadenoma when there is no suspicion for a state of endogenous hypercortisolism, we sought to determine if the test could reliably identify these pathologies during the preoperative evaluation. We hypothesized that patients with subclinical Cushing’s disease or silent ACTH-secreting tumors would have a higher delta cortisol on the ACTH stimulation tests vs. other types of macroadenoma pathologies,” Kevin Pantalone, DO, ECNU, FACE, staff endocrinologist and director of clinical research in the department of endocrinology at Cleveland Clinic, told Endocrine Today.

Pantalone and colleagues performed a retrospective chart review of 148 patients with pituitary macroadenoma who underwent preoperative ACTH stimulation tests, with the goal of determining whether the test can aid in the identification of ACTH-staining pathology.

Overall, 9.5% of patients showed diffuse staining, 50.6% showed other-staining (diffuse staining for anterior pituitary hormones other than ACTH) and 39.9% showed no staining (no staining for any anterior pituitary hormones).

The researchers calculated delta total cortisol at 30 and 60 minutes from baseline and reviewed preoperative ACTH stimulation tests. Additionally, Pantalone and colleagues compared the basal and maximal delta cortisol between the ACTH-staining pituitary macroadenoma and the non-ACTH staining (n = 134), other staining (n = 75) and non-staining (n = 59) tumors.

According to data reported at the American Association of Clinical Endocrinologists Annual Scientific and Clinical Congress, the ACTH-staining group had higher mean basal cortisol levels compared with the non-ACTH-staining (P = .012), other staining (P = .018) and the non-staining (P = .012) tumors. The researchers found no significant differences in maximal delta cortisol between the groups.

“While we found basal cortisol levels were higher in patients with ACTH-staining pituitary microadenoma vs. non-ACTH-staining macroadenoma, the large variability in cortisol values did not allow for clinical utility,” Pantalone told Endocrine Today.

“Unfortunately, in the end, our study was limited by the number of cases with ACTH-staining pathology. Thus, we were unable to determine if the ACTH stimulation test could reliably assist clinicians in potentially identifying ACTH-staining pathology in the preoperative setting,” he said. “A multicenter study, affording a large number of ACTH-staining tumors, is needed. This may allow for us to determine if the ACTH-stimulation test can really be clinically useful in preoperatively identifying ACTH-staining pathology.” – by Amber Cox

Science Teacher Receives Support After Cushing’s Disease Diagnosis

I find it amazing that it’s newsworthy in this day and age for anyone receiving support after a diagnosis.  Of course, a diagnosed person should be getting support as a matter of course.  If she had cancer, everyone would be all over this.

For Kara Murrow, the most rewarding moments as a teacher come when students learn about animals in the classroom. So it’s difficult for the Bonham Elementary fifth-grade science and social studies teacher to be away from school while she prepares for surgery.

“I enjoy it, and I know my kids enjoy the class and enjoy science because of it,” Murrow said. “With the science club I do after school once a week, the kids get upset when it gets canceled because of meetings. Not having it now is upsetting, too.”

Murrow was diagnosed this month with Cushing’s disease, a condition that develops when a tumor on the pituitary gland causes it to secrete too much adrenocorticotropic hormone. Murrow, who moved to West Texas from Arizona three years ago, said she has received support from Midland ISD employees and others in the local community.

Murrow’s mother, Louise Gonzalez, also appreciates Midlanders’ concerns for her daughter.

“People in Midland have been wonderful, considering how new we are to the area,” Gonzalez said. “The school district sent out the GoFundMe page and there’s been an outpouring of support for that. People at my church always ask me.”

Murrow’s family is collecting donations from the website GoFundMe to cover the costs of medical and travel expenses. Murrow and her husband, Kai, recently spent money on hospital stays connected to their 4-year-old son’s food sensitivities.

“They’ve been paying off those bills and doing OK until this came,” Gonzalez said. “Plus, she’s been going to the doctor about this. Because Cushing’s is so rare, doctors don’t recognize it.”

Murrow was diagnosed with the disease after medical professionals discovered a tumor on her pituitary gland. For six years, she experienced symptoms — including weight gain, dizziness and headaches — but said doctors couldn’t determine the cause. Murrow was thankful when she received an answer.

“It was a huge relief to finally have a diagnosis and know that I wasn’t crazy or making things up,” Murrow said. “It’s weird to be excited about a brain tumor. It’s a relief to know what was happening and that I have a solution.”

Murrow traveled this week to Barrow Neurological Institute in Phoenix, where she’s scheduled to undergo surgery to remove the tumor. Though Murrow said recovery lasts several months, she hopes to return to the classroom next school year.

Jaime White, fourth-grade language arts and social studies teacher at Bonham, said both staff and students miss her presence. She said Murrow expresses concern for her students during her time away.

“She’s worried about how kids will do on the STAAR [State of Texas Assessments of Academic Readiness],” White said. “She doesn’t want them to think she abandoned them. The disease has to take center stage.”

At school, White said she noticed her colleague’s dedication toward helping her students understand science.

“She’s hands-on,” White said. “When it comes to science, she’s always making sure the kids are doing some sort of experiment. She wants to make sure the kids grasp it.”

Murrow teaches students about animals through dissections and presentations. Before she became a teacher nine years ago, she coordinated outreach programs at an Arizona zoo.

When she came to MISD, Murrow saw an opportunity to generate enthusiasm about science. She launched an invite-only science club for fifth-graders who show interest in the subject.

“I started it because there wasn’t really anything,” Murrow said. “They have tutorials for reading and math. There’s not a lot kids can do with science after school. They get science in the younger grades, but the focus is on reading and math. Science is something kids really enjoy.”

Though Murrow is disappointed about not being able to facilitate the club, she recognizes the importance of her upcoming surgery. She’s happy her mother, husband and two children will be in Phoenix for support.

“I hope that it will bring about a sense of relief to all the symptoms I’ve been dealing with and provide a chance for myself and my family to continue along with a full life,” Murrow said.

From http://www.mrt.com/news/local/article/Science-teacher-receives-support-after-11026581.php