Gene test for growth hormone deficiency developed

A new test developed by University of Manchester and NHS scientists could revolutionise the way children with growth hormone deficiency are diagnosed.

Children suspected of having GHD – which cause growth to slow down or stop and other serious physical problems—currently require a test involving fasting for up to 12 hours.

The fasting is followed by an intravenous infusion in hospital and up to 10 blood tests over half a day to measure growth hormone production.

Because the current test is unreliable, it often has to be done twice before growth hormone injections can be prescribed.

Now the discovery—which the team think could be available within 2 to 5 years -could reduce the process to a single blood test, freeing up valuable time and space for the NHS.

Dr. Adam Stevens from The University of Manchester and Dr. Philip Murray from Manchester University NHS Foundation Trust, were part of the team whose results are published in JCI Insight today.

Dr. Stevens said: “We think this is an important development in the way doctors will be able to diagnose growth hormone deficiency – a condition which causes distress to many thousands of children in the UK

“This sort of diagnostic would not be available even a few years ago but thanks to the enormous computing power we have, and advances in genetics, it is now possible for this aspect of care to be made so much easier for patients – and the NHS.

“These volume of data involved is so huge and complicated that traditional data-processing application software is inadequate to deal with it.”

Comparing data from 72 patients with GHD and 26 healthy children, they used high powered computers to examine 30,000 genes—the full gene expression- of each child.

A sophisticated mathematical technique called Random Forest Analysis analysed around three million separate data points to compare different gene patterns between the children with and without GHD.

The research identified 347 genes which when analysed with the computer algorithm can determine whether a child has GHD or not and thus whether they will benefit from treatment.

Growth hormone deficiency (GHD) occurs when the pituitary gland—which is size of a pea- fails to produce enough growth hormone. It more commonly affects children than adults.

Many teenagers with GHD have poor bone strength, fatigue and lack stamina as well as depression, lack of concentration, poor memory and anxiety problems.

GHD occurs in roughly 1 in 5,000 people. Since the mid-1980s, synthetic growth hormones have been successfully used to treat children—and adults—with the deficiency.

Dr. Murray added: “This study provides strong proof of concept, but before it is in a position to be adopted by the NHS, we must carry out a further validation exercise which will involve comparing our new diagnostic with the existing test.

“Once we have crossed that hurdle, we hope to be in a position for this to be adopted within 2 to 5 years – and that can’t come soon enough for these children.”

Child Growth Foundation manager Jenny Child’s daughter has Growth Hormone Deficiency.

She said: Growth Hormone Deficiency isn’t just about growth, as lack of growth hormone impacts the child in many ways, such as lack of strength and they can find it difficult to keep up physically with their peers. It impacts the child’s self-esteem as they are often treated as being much younger, because of their size. Growth hormone treatment allows the child to grow to their genetic potential.

“A growth hormone stimulation test can be very daunting for both child and parents. The test can make the child feel quite unwell and they can experience headaches, nausea and unconsciousness through hypoglycaemia.”

 Explore further: Northern climes make a difference with growth hormone treatment

More information: Philip G. Murray et al. Transcriptomics and machine learning predict diagnosis and severity of growth hormone deficiency, JCI Insight (2018). DOI: 10.1172/jci.insight.93247

Detailed MRI Analysis Provides Correlations with Clinical Features and Response to Treatment in Cushing’s Disease

Detailed imaging analysis of patients with Cushing’s disease (CD) and other disorders caused by pituitary adenomas (tumors that arise from the pituitary, a small gland in the brain) provides correlation with clinical characteristics and treatment response, a new Turkish study reports.

The research, “Clinicopathological significance of baseline T2-weighted signal intensity in functional pituitary adenomas,” appeared in the journal Pituitary.

Diagnosis of pituitary adenomas is often done with magnetic resonance imaging (MRI), which provides data on the tumor’s localization, its invasiveness, as well as cell death and other changes. However, MRI does not enable precise evaluation of the tumor’s hormone production and behavior.

Studies on T2-weighted signal intensity (T2-WSI) — one of the basic parameters in MRI scans that highlights fat and water in the body — shows that it correlates with collagen content, degree of fibrosis (scarring), amyloid protein accumulation, and granulation pattern of somatotroph adenomas, which produce excessive levels of growth hormone, causing acromegaly (a hormonal disorder that results from too much growth hormone in the body).

Evaluation of granulation patterns is key in predicting response to somatostatin analogues (SSAs) treatment, the researchers observed. SSAs are intended to stop excess hormone production.

In contrast, analysis of T2-WSI in corticotroph adenomas — benign tumors typical in Cushing’s disease patients that release elevated levels of adrenocorticotropin (ACTH) – is still lacking.

The research team assessed the correlation of T2-WSI with clinical features, granulation patterns, and response to treatment in patients with functional pituitary adenomas (FPAs), which are collectively characterized by excessive production of one or more hormones.

Specifically, scientists focused on 29 patients with Cushing’s disease, 87 with acromegaly, and 78 with prolactinoma, a type of benign pituitary tumor that produces elevated amounts of prolactin.

Results showed that while most somatotroph adenomas (53%) were hypointense, which means a darker image on MRI, the majority of prolactinomas (55%) and corticotroph adenomas (45%) were at least generally hyperintense, meaning lighter on image.

Data also revealed that hyperintense somatotroph adenomas were larger, sparsely granulated, and exhibited reduced shrinkage after treatment with SSAs.

In contrast, hypointense tumors were associated with higher levels of baseline insulin-like growth factor (IGF)-1% ULN, a predictor of insulin sensitivity, and a better response to SSAs.

In women with prolactinomas, hyperintensity correlated with smaller tumor diameter. In turn, hypointense prolactinomas were linked with younger age at diagnosis, higher baseline prolactin levels, and resistance to treatment with a dopamine agonist.

Scientists also found that hyperintense corticotroph adenomas correlated with larger tumor size and a sparsely granulated pattern. No difference was found between hyper and hypointense adenomas on cortisol and ACTH levels.

Investigators also reported that T2-WSI was not correlated with better surgical outcomes or with recurrent Cushing’s disease. Analysis of tumor shrinkage in these patients was not possible, the researchers noted.

“Although in present there is no immediate clinical application, we believe that if medical shrinkage of corticotrophs ever became a part of clinical practice, similar analyses could be performed in the future,” the researchers wrote.

“Further studies with larger series are required in order to make stronger suggestions,” they added.

From https://cushingsdiseasenews.com/2018/03/23/detailed-mri-analysis-correlates-with-cushings-disease-clinical-features/

Late-night Salivary Cortisol a Poor Approach for Detecting Cushing’s in Obese Patients

Assessment of late-night salivary cortisol (LNSC) levels is a poor diagnostic tool for detecting Cushing’s disease in obese patients, a new study from Germany shows.

The test demonstrated a particularly poor sensitivity in obese people, meaning it will often suggest a patient has Cushing’s disease when that is not the case — called a false-positive.

The study, “Specificity of late‑night salivary cortisol measured by automated electrochemiluminescence immunoassay for Cushing’s disease in an obese population,” appeared in the Journal of Endocrinological Investigation.

Although excessive weight gain is a common symptom of Cushing’s disease, existing indications advise clinicians to test for Cushing’s in obese people only if the disease is clinically suspected.

The utility of measuring LNSC for Cushing’s disease screening is well established. However, differences in assays, sample collection methods, and controls have led to a great variability in the proposed reference ranges and cut-off values. Also, according to the Endocrine Society, the influence of gender, age, and co-existing medical conditions on LNSC concentrations is still unclear.

Regarding obesity, data on the specificity of assessing late-night salivary cortisol levels is contradictory, as some studies found no differences while others reported lower specificity compared to healthy individuals.

An additional factor complicating LNSC measures in obese people is the prevalence of type 2 diabetes mellitus (T2DM), which may also lead to elevated cortisol levels.

Research showed a high rate of false-positive LNSC measurements in obese patients with poorly controlled type 2 diabetes. Also, in patients with recently diagnosed diabetes, investigators found that LNSC had very low specificity — the proportion of patients with Cushing’s who test positive — and a poor predictive value.

Recent reports showed a high diagnostic accuracy using automated electrochemiluminescent assays (ECLIA) in patients with Cushing’s disease. These methods use special labels conjugated to antibodies that produce light when they bind to a specific target.

The research team used an ECLIA assay to test the specificity of LNSC in obese patients both with and without diabetes. The investigators also intended to establish a reference range and cut-off value for this diagnostic approach.

Adults who requested weight loss treatment were included in the study, including 34 patients with a confirmed diagnosis of Cushing’s and 83 obese people, defined as having a body mass index (BMI) of at least 35 kg/m2. Forty healthy individuals were also analyzed.

Eight out of the 34 Cushing’s patients had a BMI within the obese range, which correlates with an overlap in patients awaiting bariatric surgery for weight loss, the investigators observed.

All subjects underwent LNSC assessment at 11 p.m. Results revealed significant differences in mean LNSC values — 19.9 nmol/L in Cushing’s disease patients, 10.9 nmol/L in obese subjects, and 4.7 nmol/L in those of normal weight.

Compared to healthy and obese participants, measuring LNSC in Cushing’s disease patients had a maximum sensitivity of 67.6% and a specificity of 85.4%. This was lower than prior data from obese patients with two features of Cushing’s disease.

The cut-off value for detecting Cushing’s was 12.3 nmol/L, which is in line with other studies “and underlines the importance of an evaluation with an obese cohort vs. [Cushing’s disease],” the investigators wrote.

Results did not show an association between BMI, type 2 diabetes, and LNSC for all groups.

“In our obese cohort, we found that LNSC assayed by ECLIA had a low specificity in the diagnosis of [Cushing’s disease],” the researchers wrote. “However, the clear advantage of LNSC over other tests is the simple and stress-free sampling method.”

From https://cushingsdiseasenews.com/2018/03/29/nighttime-salivary-cortisol-poor-approach-detect-cushings-disease-obese-patients/

USC’s 7 Tesla MRI scanner first to identify Cushing’s disease in US patient

A noninvasive 7 Tesla MRI scanner at University of Southern California is the first 7T scanner to be used on a patient with Cushing’s disease in the U.S., according to a USC news release.

When a brain tumor was found to be “MRI-negative” in a 28-year-old female patient, physicians at the USC’s Pituitary Center were unsatisfied with the results. After deciding to use the Neuroimaging and Informatics Institute’s (INI) new ultrahigh field 7 Tesla MRI scanner to localize the tumor, the patient was officially diagnosed with Cushing’s disease and researchers were finally able to [be] see the tumor that would’ve otherwise appeared hidden in a standard MRI.

Cushing’s disease is caused by a pituitary microadenoma, or very small tumor, which results in chronically elevated cortisol. Symptoms include weight gain, skin bruising and hair loss and if left untreated, the condition can be fatal.  Because of this case, USC researchers believe the 7T scanner will be able to replace the standard, and invasive, method of clinical diagnosis, according to the news release.

“It’s clear that this is the beginning of a new frontier for ultrahigh field MR technologies,” said Arthur Toga, PhD, director of the INI, in a prepared statement. “The enhanced image quality opens many doors for neuroscientists in both research and clinical settings.”

From http://www.healthimaging.com/topics/neuroimaging/uscs-7-tesla-mri-scanner-first-identify-cushings-disease-us-patient

Repeat Checks of Cortisol Levels in Saliva May Improve Use of Metopirone as Cushing’s Treatment

Measuring cortisol levels in saliva multiple times a day is a convenient and useful way to determine the best course of treatment for patients with Cushing’s syndrome, a preliminary study shows.

The research, “Multiple Salivary Cortisol Measurements Are a Useful Tool to Optimize Metyrapone Treatment in Patients with Cushing’s Syndromes Treatment: Case Presentations,” appeared in the journal Frontiers of Endocrinology.

Prompt and effective treatment for hypercortisolism — the excessive amount of cortisol in the blood — is essential to lowering the risk of Cushing’s-associated conditions, including infections, cardiovascular disease, and stroke.

Steroid hormone inhibitors, such as HRA Pharma’s Metopirone (metyrapone), have been used significantly in Cushing’s syndrome patients.

These therapies not only suppress cortisol levels, but also avoid adrenal insufficiency (where not enough cortisol is produced) and restore the circadian rhythm, which is disrupted in Cushing’s patients. However, effective medical treatment requires monitoring cortisol activity throughout the day.

Salivary measurements of cortisol are a well-known method for diagnosing and predicting the risk of recurrence of Cushing’s syndrome. The method is convenient for patients and can be done in outpatient clinics. However, the medical field lacks data on whether measuring cortisol in saliva works for regulating treatment.

Researchers analyzed the effectiveness of salivary cortisol measurements for determining the best dosage and treatment timing of Cushing’s patients with Metopirone.

The study included six patients, three with cortisol-secreting masses in the adrenal glands and and three with ACTH (or adrenocorticotropin)-secreting adenomas in the pituitary glands, taking Metopirone. Investigators collected samples before and during treatment to assess morning serum cortisol and urinary free cortisol (UFC). Patients also had salivary cortisol assessments five times throughout the day.

Saliva samples were collected at 6 a.m. (wake-up time), 8 a.m. (before breakfast), noon (before lunch), 6 p.m. (before dinner), and 10 p.m. (before sleep).

Other studies have used UFC assessments to monitor treatment. However, the inability of this parameter to reflect changes in diurnal cortisol requires alternative approaches.

Results showed that although UFC was normalized in five out of six patients, multiple salivary cortisol measurements showed an impaired diurnal cortisol rhythm in these patients.

Whereas patients with cortisol-secreting adrenocortical adenoma showed elevated cortisol levels throughout the day, those with ACTH-secreting pituitary adenoma revealed increased levels mainly in the morning. This finding indicates that “the significance of elevated morning cortisol levels is different depending on the disease etiology,” the researchers wrote.

In a prospective case study to better assess the effectiveness of performing multiple salivary cortisol assessments, the research team analyzed one of the participants who had excessive cortisol production that was not controlled with four daily doses of Metoripone (a daily total of 2,250 mg).

Results revealed that cortisol levels increased before each dosage. After the patient’s treatment regimen was changed to a 2,500 mg dose divided into five daily administrations, researchers observed a significant improvement in the diurnal cortisol pattern, as well as in UFC levels.

Subsequent analysis revealed that performing multiple salivary cortisol measurements helps with a more precise assessment of excess cortisol than analyzing UFC levels, or performing a unique midnight salivary cortisol collection, the researchers said.

Although more studies are required, the results “suggest that multiple salivary cortisol measurements can be a useful tool to visualize the diurnal cortisol rhythm and to determine the dose and timing of metyrapone [Metopirone] during the treatment in patients with [Cushing’s syndrome],” the researchers wrote.

Future studies should include a larger sample size, evaluate changes over a longer term, use a standardized protocol for treatment dosing and timing, and evaluate changes in a patient’s quality of life, the investigators said.

From https://cushingsdiseasenews.com/2018/02/15/multiple-saliva-cortisol-checks-cushings-metyrapone-study/

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