An evaluation of untargeted metabolomics methods to characterize inborn errors of metabolism.

Inborn errors of metabolism (IEMs) encompass a diverse group of disorders that can be difficult to classify due to heterogenous clinical, molecular, and biochemical manifestations. Untargeted metabolomics platforms have become a popular approach to analyze IEM patient samples because of their ability to detect many metabolites at once, accelerating discovery of novel biomarkers, and metabolic mechanisms of disease. However, there are concerns about the reproducibility of untargeted metabolomics research due to the absence of uniform reporting practices, data analyses, and experimental design guidelines. Therefore, we critically evaluated published untargeted metabolomic platforms used to characterize IEMs to summarize the strengths and areas for improvement of this technology as it progresses towards the clinical laboratory. A total of 96 distinct IEMs were collectively evaluated by the included studies. However, most of these IEMs were evaluated by a single untargeted metabolomic method, in a single study, with a limited cohort size (55/96, 57%). The goals of the included studies generally fell into two, often overlapping, categories: detecting known biomarkers from many biochemically distinct IEMs using a single platform, and detecting novel metabolites or metabolic pathways. There was notable diversity in the design of the untargeted metabolomic platforms. Importantly, the majority of studies reported adherence to quality metrics, including the use of quality control samples and internal standards in their experiments, as well as confirmation of at least some of their feature annotations with commercial reference standards. Future applications of untargeted metabolomics platforms to the study of IEMs should move beyond single-subject analyses, and evaluate reproducibility using a prospective, or validation cohort.

Inflammatory biomarkers in the evaluation of pediatric endogenous Cushing syndrome.

OBJECTIVE: Inflammatory biomarkers, such as absolute neutrophil and lymphocyte counts, neutrophil-to-lymphocyte ratio (NLR), platelet (PLT)-to-lymphocyte ratio (PLR) and monocyte-to-lymphocyte ratio (MLR), are associated with the progression and development of several disorders. Although patients with Cushing syndrome (CS) have immunosuppression with altered leucocyte counts, the profile of the inflammatory biomarkers in these patients has not been extensively studied. DESIGN: We compared a panel of inflammatory biomarkers in patients with active endogenous CS (n of complete blood count (CBC) reports = 319) and eucortisolemic subjects of similar age, gender and BMI (n of CBC reports = 93). Patients were divided into two age groups (6-12 years at the time of CBC and >12 years at the time of CBC) based on age differences in normal reference ranges. RESULTS: Patients with CS had higher NLR vs controls (6-12 years: 2.47 (1.86, 3.32) vs 1.35 (1.11, 2.27), P < 0.0001; >12 years: 3.00 (2.23-4.17) vs 1.80 (1.23-2.31), P < 0.0001). Similarly, absolute neutrophil and lymphocyte counts, MLR and PLR differed between patients with CS and controls. The inflammatory biomarkers correlated with indices of cortisol secretion, such as midnight serum cortisol, 24-h urinary free cortisol and morning cortisol. On receiver operating characteristic analysis, NLR showed high area under the curve (AUC) (6-12 years: cutoff of 1.72 had AUC: 0.77, >12 years: cutoff of 2.35 had AUC: 0.81). CONCLUSIONS: We conclude that multiple inflammatory biomarkers differed between patients with CS and controls suggesting substantial effects of hypercortisolemia on the immune system.

Scoping review of COVID-19-related systematic reviews and meta-analyses: can we really have confidence in their results?

AIM: The aim of this study was to systematically appraise the quality of a sample of COVID-19-related systematic reviews (SRs) and discuss internal validity threats affecting the COVID-19 body of evidence. DESIGN: We conducted a scoping review of the literature. SRs with or without meta-analysis (MA) that evaluated clinical data, outcomes or treatments for patients with COVID-19 were included. MAIN OUTCOME MEASURES: We extracted quality characteristics guided by A Measurement Tool to Assess Systematic Reviews-2 to calculate a qualitative score. Complementary evaluation of the most prominent published limitations affecting the COVID-19 body of evidence was performed. RESULTS: A total of 63 SRs were included. The majority were judged as a critically low methodological quality. Most of the studies were not guided by a pre-established protocol (39, 62%). More than half (39, 62%) failed to address risk of bias when interpreting their results. A comprehensive literature search strategy was reported in most SRs (54, 86%). Appropriate use of statistical methods was evident in nearly all SRs with MAs (39, 95%). Only 16 (33%) studies recognised heterogeneity in the definition of severe COVID-19 as a limitation of the study, and 15 (24%) recognised repeated patient populations as a limitation. CONCLUSION: The methodological and reporting quality of current COVID-19 SR is far from optimal. In addition, most of the current SRs fail to address relevant threats to their internal validity, including repeated patients and heterogeneity in the definition of severe COVID-19. Adherence to proper study design and peer-review practices must remain to mitigate current limitations.

A case of Carney triad complicated by renal cell carcinoma and a germline SDHA pathogenic variant.

SUMMARY: Succinate dehydrogenase deficiency has been associated with several neoplasias, including renal cell carcinoma (RCC) and those associated with hereditary paraganglioma (PGL)/ pheochromocytoma (PHEO) syndromes, Carney dyad, and Carney triad. Carney triad is a rare multitumoral syndrome characterized by co-existing PGL, gastrointestinal stromal tumor (GIST), and pulmonary chondroma (CHO). We report a case of a 57-year-old male who presented with para-aortic and gastroesophogeal masses, and a right renal superior pole lesion, which were classified as multiple PGLs, a GIST, and a clear cell renal carcinoma, respectively, on pathology following surgical resection. Additionally, a CHO was diagnosed radiologically, although no biopsy was performed. A diagnosis of Carney triad was made. SDHB immunohistochemical staining was negative for the PGL and the GIST, indicating SDH-deficiency. Interestingly, the renal cell carcinoma (RCC) stained positive for both SDHB and SDHA. Subsequent genetic screening of SDH subunit genes revealed a germline inactivating heterozygous SDHA pathogenic variant (c.91 C>T, p.R31X). Loss of heterozygosity was not detected at the tumor level for the RCC, which likely indicated the SDHA variant would not be causative of the RCC, but could still predispose to the development of neoplasias. To the knowledge of the authors this is the first reported case of an SDHA pathogenic variant in a patient with Carney triad complicated by RCC. LEARNING POINTS: The succinate dehydrogenase enzyme is encoded by four subunit genes (SDHA, SDHB, SDHC, and SDHD; collectively referred to as SDHx), which have been implicated in several neoplasias and are classified as tumor suppressor genes. Carney triad is a rare multiple-neoplasia syndrome presenting as an association of PGLs, GISTs, and CHOs. Carney triad is most commonly associated with hypermethylation of SDHC as demonstrated in tumor tissue, but approximately 10% of cases are due to pathogenic SDHx variants. Although SDHB pathogenic variants are most commonly reported in SDH-deficient renal cell carcinoma, SDHA disease-causing variants have been reported in rare cases.

Volumetric Modeling of Adrenal Gland Size in Primary Bilateral Macronodular Adrenocortical Hyperplasia.

CONTEXT: Radiological characterization of adrenal size in primary bilateral macronodular adrenocortical hyperplasia (PBMAH) has not been previously investigated. OBJECTIVE: We hypothesized that volumetric modeling of adrenal gland size may correlate with biochemical disease severity in patients with PBMAH. Secondary analysis of patients with concurrent primary aldosteronism (PA) was performed. DESIGN: A retrospective cross-sectional analysis of 44 patients with PBMAH was conducted from 2000 to 2019. SETTING: Tertiary care clinical research center. PATIENTS: Patients were diagnosed with PBMAH based upon clinical, genetic, radiographic and biochemical characteristics. INTERVENTION: Clinical, biochemical, and genetic data were obtained. Computed tomography scans were used to create volumetric models by manually contouring both adrenal glands in each slice using Vitrea Core Fx v6.3 software (Vital Images, Minnetonka, Minnesota). MAIN OUTCOME AND MEASURES: 17-hydroxycorticosteroids (17-OHS), ARMC5 genetics, and aldosterone-to-renin ratio (ARR) were retrospectively obtained. Pearson test was used for correlation analysis of biochemical data with adrenal volume. RESULTS: A cohort of 44 patients with PBMAH was evaluated, with a mean age (±SD) of 53 ±â€…11.53. Eight patients met the diagnostic criteria for PA, of whom 6 (75%) were Black. In the Black cohort, total adrenal volumes positively correlated with midnight cortisol (R = 0.76, P = 0.028), urinary free cortisol (R = 0.70, P = 0.035), and 17-OHS (R = 0.87, P = 0.0045), with a more pronounced correlation with left adrenal volume alone. 17-OHS concentration positively correlated with total, left, and right adrenal volume in patients harboring pathogenic variants in ARMC5 (R = 0.72, P = 0.018; R = 0.65, P = 0.042; and R = 0.73, P = 0.016, respectively). CONCLUSIONS: Volumetric modeling of adrenal gland size may associate with biochemical severity in patients with PBMAH, with particular utility in Black patients.

Prevalence of Diabetes and Hypertension and Their Associated Risks for Poor Outcomes in Covid-19 Patients.

Coronavirus disease 2019 (Covid-19) has affected millions of people and may disproportionately affect those with hypertension and diabetes. Because of inadequate methods in published systematic reviews, the prevalence of diabetes and hypertension and associated risks of poor outcomes in Covid-19 patients are unknown. We searched databases from December 1, 2019, to April 6, 2020, and selected observational peer-reviewed studies in English of patients with Covid-19. Independent reviewers extracted data on study participants, interventions, and outcomes and assessed risk of bias, and the certainty of evidence. We included 65 (15 794 participants) observational studies at moderate to high risk of bias. Overall prevalence of diabetes and hypertension was 12% (95% confidence interval [CI], 10-15; n = 12 870; I 2: 89%), and 17% (95% CI, 13-22; n = 12 709; I 2: 95%), respectively. In severe Covid-19, the prevalence of diabetes and hypertension were 18% (95% CI, 16-20; n = 1099; I 2: 0%) and 32% (95% CI, 16-54; n = 1078; I 2: 63%), respectively. Unadjusted relative risk for intensive care unit admission and mortality were 1.96 (95% CI, 1.19-3.22; n = 8890; I 2: 80%; P = .008) and 2.78 (95% CI, 1.39-5.58; n = 2058; I 2: 75%; P = .0004) for diabetics; and 2.95 (95% CI, 2.18-3.99; n = 1737; I 2: 0%; P < .001) and 2.39 (95% CI, 1.54-3.73; n = 3107; I 2: 66%; P < .001) for hypertensives. Neither diabetes (1.50; 95% CI, 0.90-2.50; n = 1991; I 2: 74%; P = .119) nor hypertension (1.48; 95% CI, 0.99-2.23; n = 2023; I 2: 69%; P = .058) was associated with severe Covid-19. In conclusion, the risk of intensive care unit admission and mortality for patients with diabetes or hypertension who developed Covid-19 is increased compared with those without these comorbidities. PROSPERO REGISTRATION NUMBER: CRD42020176582.

Endocrine Conditions and COVID-19.

COVID-19 was declared a global pandemic by the WHO and has affected millions of patients around the world. COVID-19 disproportionately affects persons with endocrine conditions, thus putting them at an increased risk for severe disease. We discuss the mechanisms that place persons with endocrine conditions at an additional risk for severe COVID-19 and review the evidence. We also suggest precautions and management of endocrine conditions in the setting of global curfews being imposed and offer practical tips for uninterrupted endocrine care.

Inhibin A as a tumor marker for primary bilateral macronodular adrenal hyperplasia.

SUMMARY: Primary bilateral macronodular adrenal hyperplasia (PBMAH) is a rare cause of ACTH-independent Cushing syndrome (CS). This condition is characterized by glucocorticoid and/or mineralocorticoid excess, and is commonly regulated by aberrant G-protein coupled receptor expression may be subclinical, allowing the disease to progress for years undetected. Inhibin A is a glycoprotein hormone and tumor marker produced by certain endocrine glands including the adrenal cortex, which has not been previously investigated as a potential tumor marker for PBMAH. In the present report, serum inhibin A levels were evaluated in three patients with PBMAH before and after adrenalectomy. In all cases, serum inhibin A was elevated preoperatively and subsequently fell within the normal range after adrenalectomy. Additionally, adrenal tissues stained positive for inhibin A. We conclude that serum inhibin A levels may be a potential tumor marker for PBMAH. LEARNING POINTS: PBMAH is a rare cause of CS. PBMAH may have an insidious presentation, allowing the disease to progress for years prior to diagnosis. Inhibin A is a heterodimeric glycoprotein hormone expressed in the gonads and adrenal cortex. Inhibin A serum concentrations are elevated in some patients with PBMAH, suggesting the potential use of this hormone as a tumor marker. Further exploration of serum inhibin A concentration, as it relates to PBMAH disease progression, is warranted to determine if this hormone could serve as an early detection marker and/or predictor of successful surgical treatment.