scholarly journals Sensitivity and specificity of the macimorelin test for diagnosis of AGHD

2020 ◽  
Author(s):  
Jose M Garcia ◽  
Beverly M. K. Biller ◽  
Marta Korbonits ◽  
Vera Popovic ◽  
Anton Luger ◽  
...  

Objective: The macimorelin test is approved for the diagnosis of adult growth hormone deficiency (AGHD) based on its efficacy vs the insulin tolerance test (ITT). Macimorelin has a significant advantage over ITT in avoiding hypoglycemia. Analyses were conducted to determine whether macimorelin performance is affected by age, body mass index (BMI), or sex, and evaluate its performance vs ITT over a range of GH cutpoints. Design: Post hoc analyses of data from a previous randomized phase 3 study included participants aged 18-66 years with BMI <37 kg/m2 and high (Group A), intermediate (Group B), or low (Group C) likelihood for AGHD based on pituitary history, and matched controls (Group D). Methods: Probability of AGHD was estimated using unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted logistic models. Area under the curve (AUC) of the estimated receiver operating characteristic (ROC) curve (range, 0-1; 1=perfect) was compared for adjusted vs unadjusted models. Separate analyses evaluated agreement, sensitivity, and specificity for macimorelin and ITT using cutpoints of 2.8, 4.0, 5.1, and 6.5 ng/mL. Results: For participants in Group A (n=41) and Group D (n=29), unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted models had ROC AUCs (95% CIs) of 0.9924 (0.9807-1), 0.9924 (0.9807-1), 0.9916 (0.9786-1), and 0.9950 (0.9861-1), respectively. Conclusions: Macimorelin performance was not meaningfully affected by age, BMI, or sex, indicating robustness for AGHD diagnosis. Of the 4 GH cutpoints evaluated, the cutpoint of 5.1 ng/mL provided maximal specificity (96%) and high sensitivity (92%) and was in good overall agreement with the ITT at the same cutpoint (87%).

2010 ◽  
Vol 6 (2) ◽  
pp. 45
Author(s):  
Torben Laursen ◽  

In patients with hypopituitarism, growth hormone (GH) deficiency is almost always present. Lack of other pituitary hormones may require prompt replacement, but lack of GH is also associated with several abnormalities, which can be improved by GH treatment. The aberrations include low bone mass and increased risk of fractures, abnormal body composition, e.g. increased fat mass and reduced lean body mass resulting in reduced muscle mass and strength. Decreased exercise capacity may be influenced by impaired cardiac performance and heat intolerance. Increased abdominal fat results in metabolic disturbancies, such as reduced insulin sensitivity and hyperlipidaemia, increasing the risk of cardiovascular diseases. Patients with hypopituitarism replaced with relevant hormones except GH have increased mortality due to cardiovascular diseases and increased morbidity. Thus, it is important to diagnose GH deficiency, which requires precise diagnostic criteria and methods. Dynamic testing of GH secretion with an insulin tolerance test or arginine plus GH-releasing hormone can be used.


2014 ◽  
Vol 10 (01) ◽  
pp. 75
Author(s):  
Kevin C J Yuen ◽  

Growth hormone deficiency (GHD) is a well-recognized clinical syndrome in adults, and its diagnosis is established through one or more GH stimulation tests. The decision to perform GH stimulation testing should be based on medical history and clinical findings, and using appropriate GH stimulation test/s for biochemical confirmation. The insulin tolerance test (ITT) remains the diagnostic test of choice; however, this test is labor intensive, contraindicated in the elderly and in adults with seizure disorders and ischemic heart disease, can be unpleasant for the patient, and is potentially hazardous. With the discontinuation of the growth hormone releasing hormone (GHRH) analog (Geref®) in the US in 2008, the glucagon stimulation test (GST) has gained increasing popularity as the alternative test to the ITT because of its availability, reproducibility, safety, lack of influence by gender and hypothalamic cause of GH deficiency (GHD), and relatively few contraindications. In this article, recommendations for performing this test, the potential drawbacks in conducting and caveats in interpreting this test, and its future perspectives are discussed.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A534-A534
Author(s):  
Edoardo Vergani ◽  
Carmine Bruno ◽  
Cesare Gavotti ◽  
Emmanuel Capobianco ◽  
Diego Currò ◽  
...  

Abstract Liver enriched antimicrobial peptide-2 (LEAP-2) is an endogenous antagonist of ghrelin, which acts as an allosteric modulator of growth hormone secretagogue receptors. It is expressed predominantly in liver, followed by kidney, jejunum, duodenum and stomach. Its expression in conditions of metabolic impairment, obesity for instance, may be upregulated, usually pairing with a concomitant reduction in ghrelin secretion. Weight gain and hyperglycaemia seem to be the main trigger factors for LEAP-2 production. Adult growth hormone deficiency (aGHD) is known as a pathological condition characterized by metabolic impairment (insulin resistance, weight gain, increased fat mass, decreased lean mass). To the best of our knowledge, no study in literature deals with the problem of circulating LEAP-2 levels in GHD. Therefore, the primary endpoint of this cross-sectional observational study was to evaluate circulating LEAP-2 levels in GHD in comparison to healthy controls whether the secondary endpoint was to evaluate any possible correlation with IGF-1 and metabolic parameters in such condition. 30 patients were included in the study. Group A included adult GHD: 15 patients, 7 females and 8 males, mean±standard error of the mean (SEM) age 54.6±3.51 years, BMI 29,95±1.63 kg/m2). The etiologies of GHD were empty sella (n=6), idiopathic (n=6), post-surgical hypopituitarism (n=2), pineal cyst (n=1). Group B was formed by controls: 15 patients, 11 females and 4 males, mean±SEM age 40.33±2.61 years, BMI 24.19±1.33 kg/m2. They were evaluated for: serum glucose and insulin, HOMA-index, QUICKI-index, Total/LDL/HDL cholesterol, triglycerides, IGF-1 and LEAP-2 (measured using Human LEAP-2 ELISA kit, Phoenix Pharmaceuticals Inc, according to manufacturer’s instructions). Circulating LEAP-2 is significantly higher in GHD than in control group (26.98±3.12 vs 18.7±1.9 ng/ml, p=0.03). LEAP-2 levels in our cohort was not influenced by BMI, while a significant direct correlation between LEAP-2 and age was detected in aGHD group. A strong significative inverse correlation between LEAP-2 and IGF-1 was evidenced in aGHD (r2=0.5). Finally, in this group, LEAP-2 inversely correlates with total cholesterol (r2=0.45). As expected circulating LEAP-2 levels, in a condition of metabolic impairment such as GHD, were higher than controls even if no correlation with BMI was evidenced in our cohort. The inverse correlation between LEAP-2 and IGF-1 in GHD patients may suggest a body adjustment in a worse clinical condition. LEAP-2 may act as a brake for ghrelin production, thus preventing further weight gain and fat mass increase, although losing its secretagogue effect.


2020 ◽  
Author(s):  
Yan Liu ◽  
Yu Zhang ◽  
Yue-guo Chen

Abstract PurposeTo evaluate the value of Scheimpflug-based biomechanical analyzer combined with tomography in detecting early keratoconus by distinguishing normal eyes from frank keratoconus (KC) and forme frusta keratoconus (FFKC) eyes in Chinese patients. MethodsThis study included 31 bilateral frank keratoconus patients, 27 unilateral clinical manifest keratoconus patients with very asymmetric eyes, and 79 control subjects with normal corneas. Corneal morphological and biomechanical parameters were measured using the Pentacam HR and Corvis ST (OCULUS, Wetzlar, Germany). The diagnostic capacity of computed parameters reflecting corneal biomechanical and morphological traits [including Belin-Ambrósio deviation index (BAD_D), Corvis biomechanical index (CBI) and tomographic and biomechanical index (TBI)] was determined using receiver operating characteristic (ROC) curves and compared by DeLong test. Additionally, the area under the curve (AUC), the best cutoff values, and Youden index for each parameter were reported. The novel corneal stiffness parameter (Stress-Strain Index or SSI) was also compared between KC, FFKC and normal eyes.ResultsEvery morphological and biomechanical index analyzed in this study was significantly different between KC, FFKC and normal eyes (p=0.000). TBI was most valuable for detecting subclinical keratoconus (FFKC eyes) with an AUC of 0.928 (P=0.000), and any forms of corneal ectasia (FFKC and frank KC eyes) with an AUC of 0.966 (P=0.000). The sensitivity and specificity of TBI for detecting FFKC was 97.5% and 77.8%, for detecting any KC was 97.5% and 89.7%, with a cut-off value of 0.375. Morphological index BAD_D and biomechanical index CBI were also very useful in distinguishing any KC eyes from normal eyes with an AUC of 0.965 and 0.934, respectively. SSI was significantly different between KC, FFKC and normal eyes (P=0.000), indicating an independent decrease in corneal stiffness in KC eyes.Conclusion Combination of Scheimpflug-based biomechanical analyzer and tomography could increase the accuracy of detecting early keratoconus in Chinese patients. TBI was the most valuable index for detecting subclinical keratoconus with high sensitivity and specificity. Evaluation of corneal biomechanical property in refractive surgery candidates is helpful to recognize potential keratoconic eyes and increase surgical safety.


Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2603
Author(s):  
Katarzyna Szczeklik ◽  
Tomasz Mach ◽  
Dorota Cibor ◽  
Danuta Owczarek ◽  
Jacek Sapa ◽  
...  

Diagnostics of Crohn’s disease (CD) requires noninvasive biomarkers facilitating early detection and differentiation of the disease. Therefore, in this study, we aimed to determine the relationship between paraoxonase-1 (PON-1), the severity of CD, oxidative stress, and inflammation in CD. The CD activity index was based on the current classification. Plasma PON-1 was measured in 47 patients with CD, and in 23 control volunteers. Using quantitative variables such as receiver operating characteristics (ROC) (area under the curve (AUC)), the diagnostic utility of PON-1 in differentiating the severity of CD was assessed. Circulating PON-1 was found to be decreased in the CD group compared to the control group (269.89 vs. 402.56 U/L, respectively), and it correlated well with the disease activity. PON-1 correlated positively with hemoglobin (Hb) (r = 0.539, p < 0.001), hematocrit (Ht) (r = 0.48, p < 0.001), total cholesterol (TC) (r = 0.343, p < 0.001), high density lipoprotein (HDL) (r = 0.536, p < 0.001), low density lipoprotein (LDL) (r = 0.54, p < 0.001), and triglyceride (TG) (r = 0.561, p < 0.001) and correlated negatively with white blood cell count (WBC) (r = −0.262, p = 0.029), platelet count (PLT) (r = −0.326, p = 0.006), C-reactive protein (CRP) (r = −0.61, p < 0.001), and malondialdehyde (MDA) (r = −0.924, p < 0.001). PON-1 as a marker for CD differentiation possessed a sensitivity and specificity of 93.62% and 91.30%, respectively. CD was found to be associated with the decrease in the levels of PON-1, which correlates well with activity of the disease and reflects the intensification of inflammation, as well as intensified lipid peroxidation. High sensitivity and specificity of PON-1 determines its selection as a good screening test for CD severity.


2021 ◽  
Vol 11 (1) ◽  
pp. 8-16
Author(s):  
Shimaa El Sharawy ◽  
Hemat El-Horany ◽  
Ibrahim Amer

Background: Serum biomarkers are commonly used for diagnosing and monitoring the disease activity of Ulcerative Colitis (UC) patients. However, their role in predicting disease severity among Egyptian patients is unknown. Objectives: The aim of this study was to correlate these biomarkers with clinical, endoscopic and histologic severity. Methods: This is a cross-sectional survey where 55 patients with UC were included to measure corrected Erythrocyte Sedimentation Rate (ESR), hematocrit (Hct), corrected ESR/albumin ratio and albumin, as well as colonoscopy and biopsy. Sensitivity and specificity, positive and negative predictive values were correlated with clinical, endoscopic, histologic severity. Results: The mean age of patients was 33 ± 8.4 years. In total, 27 (49.1%) were males and 28 (50.9%) were females. Area Under the Curve (AUC) values for the diagnosis of severe clinical disease were 0.947, 0.932, 0.727 and 0.685 for corrected ESR/albumin ratio, corrected ESR, Hct and albumin, respectively. Cut-off value to determine endoscopic severity for Hct was 34 (sensitivity: 88.89%, specificity: 83.78%, PPV: 72.7%, NPV: 93.9%, AUC: 0.963, p<0.001). Conclusion: Corrected ESR/albumin ratio was the best predictor of severe clinical activity of UC disease. Hct may be a marker of endoscopic and histological severity due to its high sensitivity and specificity as a diagnostic test.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yan Liu ◽  
Yu Zhang ◽  
Yueguo Chen

Abstract Background In vivo corneal biomechanics evaluation has been used to help screen early keratoconus in recent years. This study is to evaluate the value of a Scheimpflug-based biomechanical analyser combined with tomography in detecting subclinical keratoconus by distinguishing normal eyes from frank keratoconus (KC) and forme frusta keratoconus (FFKC) eyes in Chinese patients. Methods Study design: diagnostic test. This study included 31 bilateral frank keratoconus patients, 27 unilateral clinically manifesting keratoconus patients with very asymmetric eyes, and 79 control subjects with normal corneas. Corneal morphological and biomechanical parameters were measured using a Pentacam HR and a Corvis ST (OCULUS, Wetzlar, Germany). The diagnostic ability of computed parameters reflecting corneal biomechanical and morphological traits [including the Belin-Ambrósio deviation index (BAD_D), the Corvis biomechanical index (CBI) and the tomographic and biomechanical index (TBI)] was determined using receiver operating characteristic (ROC) curve analysis and compared by the DeLong test. Additionally, the area under the curve (AUC), the best cut-off values, and the Youden index for each parameter were reported. A novel corneal stiffness parameter, the stress-strain index (SSI), was also compared between KC, FFKC and normal eyes. Results Every morphological and biomechanical index analysed in this study was significantly different among KC, FFKC and normal eyes (P = 0.000). The TBI was most valuable in detecting subclinical keratoconus (FFKC eyes), with an AUC of 0.928 (P = 0.000), and both forms of corneal ectasia (FFKC and frank KC eyes), with an AUC of 0.966 (P = 0.000). The sensitivity and specificity of the TBI was 97.5 and 77.8 % in detecting FFKC and 97.5 and 89.7 % in detecting any KC, respectively, with a cut-off value of 0.375. The morphological index BAD_D and the biomechanical index CBI were also very useful in distinguishing eyes with any KC from normal eyes, with AUCs of 0.965 and 0.934, respectively. The SSI was significantly different between KC, FFKC and normal eyes (P = 0.000), indicating an independent decrease in corneal stiffness in KC eyes. Conclusions The combination of a Scheimpflug-based biomechanical analyser and tomography could increase the accuracy in detecting subclinical keratoconus in Chinese patients. The TBI was the most valuable index for detecting subclinical keratoconus, with a high sensitivity and specificity. Evaluation of corneal biomechanical properties in refractive surgery candidates could be helpful for recognizing potential keratoconic eyes and increasing surgical safety.


Author(s):  
Meng-Yi Han ◽  
Chen Xie ◽  
Qing-Qing Huang ◽  
Qiao-Hua Wu ◽  
Qing-Yun Deng ◽  
...  

Abstract Background Group B Streptococcal (GBS) infection is the primary agent of neonatal morbidity and mortality. Rapid and simple methods to detect GBS are Xpert GBS and GBS LB assays based on real-time polymerase chain reaction (PCR). However, since the diagnostic accuracy of the two techniques in diagnosing GBS remains unclear, we designed this study to appraise the diagnostic accuracy of the aforementioned. Methods A systematic search of all literature published before July 16, 2020 was conducted using Embase, PubMed, Web of Science, and Cochrane Library. The study quality was evaluated through Review Manager 5.3. Accordingly, data extracted in the included studies were analyzed using Meta-DiSc 1.4 and Stata 12.0 software. The diagnosis odds ratio (DOR) and bivariate boxplot were utilized to evaluate the heterogeneity. Publication bias was appraised by using Deeks’ funnel plot. Results A total of 13 studies were adopted and only 19 sets of data met the criteria. The sensitivity and specificity of Xpert GBS were 0.91 (95% CI 0.89–0.92) and 0.93 (95% CI 0.92–0.94). The area under the curve (AUC) was 0.9806. The sensitivity and specificity results of Xpert GBS LB were 0.96 (95% CI 0.95–0.98) and 0.94 (95% CI 0.92–0.95), respectively. The AUC was 0.9950. No publication bias was found. Conclusions The Xpert GBS and GBS LB assays are valuable alternative methods with high sensitivity and specificity. However, determining whether they can be used as clinical diagnostic standards for GBS is essential for the future.


Author(s):  
Emma Beeldman ◽  
Rosanne Govaarts ◽  
Marianne de Visser ◽  
Michael A. van Es ◽  
Yolande A. L. Pijnenburg ◽  
...  

AbstractCognitive and behavioural impairment in amyotrophic lateral sclerosis (ALS) negatively influences the quality of life and survival, and, therefore, screening for these impairments is recommended. We developed a cognitive screening tool, the amyotrophic lateral sclerosis–frontotemporal dementia–cognitive screen (ALS–FTD–Cog) and aimed to validate it in patients with ALS. During the current study, the Edinburgh Cognitive and Behavioural ALS Screen (ECAS) was published and we, therefore, decided to compare these two cognitive screening methods. The ALS–FTD–Cog was administered to 72 patients with ALS, 21 patients with behavioural variant FTD (bvFTD) and 34 healthy controls. Twenty-nine patients with ALS underwent the ECAS. ROC curve analyses were performed and sensitivity and specificity of the ALS–FTD–Cog and ECAS were calculated, with a neuropsychological examination (NPE) as the gold standard. Cognitive impairment was present in 28% of patients with ALS. ROC curve analyses of the ALS–FTD–Cog and ECAS showed an area under the curve (AUC) of 0.72 (95% CI 0.58–0.86) and 0.95 (95% CI 0.86–1.03), respectively. Compared to a full NPE, sensitivity and specificity of the ALS–FTD–Cog were 65.0% and 63.5% and of the ECAS 83.3% and 91.3%, respectively. The sensitivity and specificity of the ALS–FTD–Cog in patients with bvFTD were 94.4% and 100%, respectively. Test characteristics of the ALS–FTD–Cog were moderate, suggesting restricted practical value, as compared to a comprehensive NPE. The ECAS had an excellent AUC and high sensitivity and specificity, indicating that it is a valid screening instrument for cognitive impairment in ALS.


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