Adrenal Vein Sampling: Tips and Tricks.

Adrenal vein sampling (AVS) is the standard method for distinguishing unilateral from bilateral sources of autonomous aldosterone production in patients with primary aldosteronism. This procedure has been performed at limited specialized centers due to its technical complexity. With recent advances in imaging technology and knowledge of adrenal vein anatomy in parallel with the development of adjunctive techniques, AVS has become easier to perform, even at nonspecialized centers. Although rare, anatomic variants of the adrenal veins can cause sampling failure or misinterpretation of the sampling results. The inferior accessory hepatic vein and the inferior emissary vein are useful anatomic landmarks for right adrenal vein cannulation, which is the most difficult and crucial step in AVS. Meticulous assessment of adrenal vein anatomy on multidetector CT images and the use of a catheter suitable for the anatomy are crucial for adrenal vein cannulation. Adjunctive techniques such as intraprocedural cortisol assay, cone-beam CT, and coaxial guidewire-catheter techniques are useful tools to confirm right adrenal vein cannulation or to troubleshoot difficult blood sampling. Interventional radiologists should be involved in interpreting the sampling results because technical factors may affect the results. In rare instances, bilateral adrenal suppression, in which aldosterone-to-cortisol ratios of both adrenal glands are lower than that of the inferior vena cava, can be encountered. Repeat sampling may be necessary in this situation. Collaboration with endocrinology and laboratory medicine services is of great importance to optimize the quality of the samples and for smooth and successful operation. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Outcomes of Adrenal Venous Sampling in Patients with Bilateral Adrenal Masses and ACTH-Independent Cushing's Syndrome.

BACKGROUND: Management of patients with bilateral adrenal masses and ACTH-independent Cushing's syndrome (AICS) is challenging, as bilateral adrenalectomy can lead to steroid dependence and lifelong risk of adrenal crisis. Adrenal venous sampling (AVS) has been previously reported to facilitate lateralization for guiding adrenalectomy. The aim of the current study was to investigate the utility of AVS using protocol from study by Young et al. in the management of patients with bilateral adrenal masses and AICS. METHODS AND DESIGN: A retrospective review of all patients with bilateral adrenal masses and AICS who underwent AVS from 2008 to 2016 was performed. AVS for cortisol and epinephrine was performed with dexamethasone suppression. The adrenal vein to peripheral vein cortisol ratios and side-to-side cortisol lateralization ratios were calculated. RESULTS: AVS was successful in 8 of 9 patients. All 8 patients had AVS results indicating bilateral cortisol hypersecretion. Six patients underwent adrenalectomy: 3 had unilateral adrenalectomy of the larger size mass, 2 had bilateral adrenalectomy (both sides >4 cm.) and 1 had stepwise bilateral adrenalectomy. Final pathology revealed macronodular adrenal hyperplasia in all 6 patients that underwent surgery. CONCLUSION: AVS was useful in excluding a unilateral adenoma as the source of AICS in this study of patients with bilateral adrenal masses and AICS. However, adrenal mass size influenced surgical decision making more than AVS results. More data are needed before AVS can be advocated as essential for management of patients with bilateral adrenal masses and AICS.

ADDRESSING PITFALLS IN MANAGEMENT OF DIABETIC KETOACIDOSIS WITH A STANDARDIZED PROTOCOL.

Objective: To determine the efficacy and safety of a diabetic ketoacidosis (DKA)-Power Plan (PP) for guiding intravenous (IV) insulin infusions prior to anion gap (AG) closure and administering subcutaneous (SC) insulin ≥1 hour before discontinuing IV insulin. Methods: Retrospective chart review of patients with DKA before (pre-PP) (n = 60) and following (post-PP) (n = 60) implementation of a DKA-PP. Groups were compared for percentage of patients for whom IV insulin therapy was continued until AG closure, the percentage of patients receiving SC insulin ≥1 hour before discontinuation of IV insulin, and percentage of patients with rebound DKA during the index hospitalization. Results: Admission plasma glucose (514 mg/dL vs. 500 mg/dL; P = .36) and venous pH (7.2 vs. 7.2; P = .57) were similar in pre- and post-PP groups. Inappropriate discontinuation of IV insulin occurred less frequently in post-PP patients (28% vs. 7%; P = .007), with a lower frequency of rebound DKA (40% vs. 8%; P = .001) following acute management. More post-PP patients received SC insulin ≥1 hour before discontinuation of IV insulin (65% vs. 78%; P = .05). Conclusion: Implementation of a DKA-PP was associated with appropriate discontinuation of IV insulin in more patients, more frequent administration of SC insulin ≥1 hour prior to discontinuation of IV insulin, and fewer episodes of rebound DKA. Abbreviations: ADA = American Diabetes Association; AG = anion gap; BG = blood glucose; DKA = diabetic ketoacidosis; DKA-PP = DKA-Power Plan; ICU = intensive care unit; IQR = interquartile range; IV = intravenous; IVF = IV fluid; LOS = length of stay; SC = subcutaneous.

Long-term Recurrence Rates After Surgery in Primary Hyperparathyroidism.

CONTEXT: Primary hyperparathyroidism (PHPT) is the most common cause of hypercalcemia, yet long-term (5- and 10-year) recurrence rates after curative surgery have been unclear. OBJECTIVE: To perform the first systematic review and meta-analysis investigating the long-term recurrence rates of sporadic PHPT after successful parathyroidectomy. METHODS: A comprehensive search of multiple databases (including PubMed, EMBASE, Cochrane, EBSCO-CINHAL, EMBASE, Ovid, Scopus, and Google Scholar) was performed from each database's inception to January 18, 2023. Observational studies reporting at least 5 years of follow-up data after surgical resection were included. Two reviewers independently screened articles for relevance. Of 5769 articles initially identified, 242 were examined in full-text review and 34 were deemed eligible for inclusion. Two authors independently performed data extraction and study appraisal, using the National Institutes of Health study quality assessment tools. RESULTS: Of 30 658 participants, 350 patients (1.1%) experienced recurrence after resection. A meta-analysis of proportions was performed to obtain the pooled recurrence rates. The pooled estimate for overall recurrence rate was 1.56% (95% CI 0.96-2.28%; I2 = 91%). The pooled estimates for 5- and 10-year recurrence rate after resection were 0.23% (0.04-0.53%, 19 studies; I2 = 66%) and 1.03% (0.45-1.80%, 14 studies; I2 = 89%), respectively. Sensitivity analyses did not find a statistically significant difference when adjusting for study size, diagnosis, or surgical approach. CONCLUSION: Approximately 1.56% of sporadic PHPT patients eventually develop recurrence following parathyroidectomy. The initial diagnosis and procedure type does not influence recurrence rates. Consistent long-term follow-up is warranted to help identify recurrent disease.

Inequities in Diabetic Ketoacidosis Among Patients With Type 1 Diabetes and COVID-19: Data From 52 US Clinical Centers.

OBJECTIVE: We examined whether diabetic ketoacidosis (DKA), a serious complication of type 1 diabetes (T1D) was more prevalent among Non-Hispanic (NH) Black and Hispanic patients with T1D and laboratory-confirmed coronavirus disease 2019 (COVID-19) compared with NH Whites. METHOD: This is a cross-sectional study of patients with T1D and laboratory-confirmed COVID-19 from 52 clinical sites in the United States, data were collected from April to August 2020. We examined the distribution of patient factors and DKA events across NH White, NH Black, and Hispanic race/ethnicity groups. Multivariable logistic regression analysis was performed to examine the odds of DKA among NH Black and Hispanic patients with T1D as compared with NH White patients, adjusting for potential confounders, such as age, sex, insurance, and last glycated hemoglobin A1c (HbA1c) level. RESULTS: We included 180 patients with T1D and laboratory-confirmed COVID-19 in the analysis. Forty-four percent (n = 79) were NH White, 31% (n = 55) NH Black, 26% (n = 46) Hispanic. NH Blacks and Hispanics had higher median HbA1c than Whites (%-points [IQR]: 11.7 [4.7], P < 0.001, and 9.7 [3.1] vs 8.3 [2.4], P = 0.01, respectively). We found that more NH Black and Hispanic presented with DKA compared to Whites (55% and 33% vs 13%, P < 0.001 and P = 0.008, respectively). After adjusting for potential confounders, NH Black patients continued to have greater odds of presenting with DKA compared with NH Whites (OR [95% CI]: 3.7 [1.4, 10.6]). CONCLUSION: We found that among T1D patients with COVID-19 infection, NH Black patients were more likely to present in DKA compared with NH White patients. Our findings demonstrate additional risk among NH Black patients with T1D and COVID-19.

Mitogen-activated protein kinase contributes to lipopolysaccharide-induced activation of corticotropin-releasing hormone synthesizing neurons in the hypothalamic paraventricular nucleus.

To determine whether the p44/p42 MAPK (ERK1/2) signaling pathway is involved in the activation of CRH-containing neurons in the hypothalamic paraventricular nucleus (PVN) after bacterial lipopolysaccharide (LPS) administration, Sprague Dawley rats were injected with LPS, and studied after 2, 6, 9, and 12 h. In saline-treated controls, isolated weak phosphorylated (phospho)ERK1/2 immunoreactive neurons were observed in the PVN. However, a dramatic increase in phospho-ERK1/2 immunoreactivity was apparent in the PVN 2 h after LPS administration, and gradually declined to baseline levels 9-12 h after injection. By double-labeling immunofluorescence, all CRH-containing neurons in the PVN contained phospho-ERK1/2 2 h after LPS. Intracerebroventricular administration of the MAPK inhibitor, PD98059, prevented LPS-induced ERK1/2 phosphorylation, c-fos activation, and the increase of CRH gene expression in the PVN but had no effect on c-fos activation in brainstem A2-C1/C2 regions. We conclude that LPS rapidly increases the phospho-ERK1/2 in CRH-containing neurons in the PVN and that activation of MAPKs is necessary for LPS-induced activation of the hypothalamic-pituitary-adrenal axis.

Differential effects of refeeding on melanocortin-responsive neurons in the hypothalamic paraventricular nucleus.

To explore the effect of refeeding on recovery of TRH gene expression in the hypothalamic paraventricular nucleus (PVN) and its correlation with the feeding-related neuropeptides in the arcuate nucleus (ARC), c-fos immunoreactivity (IR) in the PVN and ARC 2 h after refeeding and hypothalamic TRH, neuropeptide Y (NPY) and agouti-related protein (AGRP) mRNA levels 4, 12, and 24 h after refeeding were studied in Sprague-Dawley rats subjected to prolonged fasting. Despite rapid reactivation of proopiomelanocortin neurons by refeeding as demonstrated by c-fos IR in ARC alpha-MSH-IR neurons and ventral parvocellular subdivision PVN neurons, c-fos IR was present in only 9.7 +/- 1.1% hypophysiotropic TRH neurons. Serum TSH levels remained suppressed 4 and 12 h after the start of refeeding, returning to fed levels after 24 h. Fasting reduced TRH mRNA compared with fed animals, and similar to TSH, remained suppressed at 4 and 12 h after refeeding, returning toward normal at 24 h. AGRP and NPY gene expression in the ARC were markedly elevated in fasting rats, AGRP mRNA returning to baseline levels 12 h after refeeding and NPY mRNA remaining persistently elevated even at 24 h. These data raise the possibility that refeeding-induced activation of melanocortin signaling exerts differential actions on its target neurons in the PVN, an early action directed at neurons that may be involved in satiety, and a later action on hypophysiotropic TRH neurons involved in energy expenditure, potentially mediated by sustained elevations in AGRP and NPY. This response may be an important homeostatic mechanism to allow replenishment of depleted energy stores associated with fasting.

Case of diabetic ketoacidosis as an initial presentation of Cushing's syndrome.

SUMMARY: Diabetic ketoacidosis (DKA) is commonly encountered in clinical practice. The current case is a unique and rare presentation of DKA as the initial manifestation of Cushing's disease secondary to ACTH-secreting pituitary adenoma. Appropriate management as elaborated in the article led to total remission of diabetes as well as the Cushing's disease. LEARNING POINTS: DKA is a serious and potentially life-threatening metabolic complication of diabetes mellitus.Some well-known precipitants of DKA include new-onset T1DM, insulin withdrawal and acute illness.In a patient presenting with DKA, the presence of a mixed acid-base disorder warrants further evaluation for precipitants of DKA.We present a rare case of DKA as an initial manifestation of Cushing's disease secondary to ACTH-producing pituitary adenoma.