Pre- and peri-operative characteristics, complications and outcomes of patients with biochemically silent pheochromocytomas; a case series.

PURPOSE: Pheochromocytomas are rare tumors and biochemically silent ones with normal catecholamine levels are even rarer. Up to date, biochemically inactive pheochromocytomas are poorly investigated. We aimed to systematically assess the pre- and peri-operative characteristics and the outcomes of patients with these tumors who had been treated and followed-up in 2 tertiary centers. METHODS: Clinical, laboratory and imaging data, treatment outcomes and follow-up of biochemically silent pheochromocytoma patients were recorded. RESULTS: Ten patients (5 men) [median age at diagnosis 52.5 years (24-72)] were included. Adrenal masses were incidentally discovered in all patients except from one who presented with pheochromocytoma-related manifestations. Twenty-four-hour urine metanephrine and normetanephrine levels were in the low-normal, normal and high-normal range in 4, 4 and 2 patients and in 1, 6 and 3 patients, respectively. Tumors were unilateral [median size 46 mm (17-125)] and high density on pre-contrast CT imaging or high signal intensity on T2-weighted MRI scans were found in all cases. Pre-operatively, 5 patients were treated with phenoxybenzamine [median total daily dose 70 mg (20-100)]. Intra-operatively, 4 patients developed hypertension requiring vasodilator administration and 8 developed hypotension; vasoconstrictors were required in 5 cases. One patient, not pre-operatively treated with phenoxybenzamine, developed Takotsubo cardiomyopathy. During a median 24-month (12-88) follow-up period, one patient had disease progression. CONCLUSIONS: The majority (90%) of patients with biochemically silent pheochromocytomas developed hemodynamic instability during adrenal surgery. In patients with biochemically silent adrenal lesions and a high suspicion index for pheochromocytoma based on tumor imaging characteristics, pre-operative alpha-blockade treatment may be advisable.

Enhanced performance of a modified diagnostic test of primary aldosteronism in patients with adrenal adenomas.

OBJECTIVE: Primary aldosteronism (PA) is the commonest cause of endocrine hypertension ranging from 4.6 to 16.6% according to the diagnostic tests employed. The aim of this study was to compare the traditional saline infusion test (SIT) with the modified post-dexamethasone saline infusion test (DSIT) by applying both tests on the same subjects. METHODS: We studied 68 patients (72% hypertensives) with single adrenal adenoma and 55 normotensive controls with normal adrenal imaging. Serum cortisol, aldosterone, and plasma renin concentration (PRC) were measured and the aldosterone-to-renin ratio (ARR) was calculated. Using the mean ± 2 s.d. values from the controls, we defined the upper normal limits for cortisol, aldosterone, and PRC for both the SIT and DSIT. RESULTS: In the controls, the post-DSIT aldosterone levels and the ARR were approximately two-fold and three-fold lower, respectively, than the corresponding post-SIT values (all P = 0.001) leading to lower cut-offs of aldosterone suppression. Applying these cut-offs to patients with adrenal adenomas, the prevalence of PA was 13.2% following the SIT and 29.4% following the DSIT, respectively. In addition, 54.5% of patients with PA had concomitant autonomous cortisol secretion (ACS). Targeted treatment of PA resulted in resolution of hypertension and restoration of normal secretory aldosterone dynamics. CONCLUSIONS: The DSIT improves the diagnostic accuracy of PA, allowing for the detection of milder forms of PA in patients with adrenal adenomas. This is of particular importance as such patients may be at an increased risk of developing cardiovascular and renal morbidity that could be enhanced in the presence of concomitant ACS.

New Incretin Combination Treatments under Investigation in Obesity and Metabolism: A Systematic Review.

The worldwide upward trend in obesity in adults and the increased incidence of overweight children suggests that the future risk of obesity-related illnesses will be increased. The existing anti-obesity drugs act either in the central nervous system (CNS) or in the peripheral tissues, controlling the appetite and metabolism. However, weight regain is a common homeostatic response; current anti-obesity medications show limited effectiveness in achieving long-term weight loss maintenance; in addition to being linked to various side effects. Combined anti-obesity medications (per os or injectable) target more than one of the molecular pathways involved in weight regulation, as well as structures in the CNS. In this systematic review, we conducted a search of PubMed and The ClinicalTrials.gov up to February 2021. We summarized the Food and Drug Administration (FDA)-approved medications, and we focused on the combined pharmacological treatments, related to the incretin hormones, currently in a clinical trial phase. We also assessed the mechanism of action and therapeutic utility of these novel hybrid peptides and potential interactions with other regulatory hormones that may have beneficial effects on obesity. As we improve our understanding of the pathophysiology of obesity, we hope to identify more novel treatment strategies.

Diabetic ketoacidosis in patients treated with SGLT2 inhibitors: experience at a tertiary hospital.

PURPOSE: Diabetic ketoacidosis (DKA) is a rare and life-threatening complication in patients with diabetes. Sodium-glucose co-transporter-2 inhibitors (SGLT2i) have rarely been associated with ketoacidosis. The aim of this retrospective study was to investigate DKA episodes occurring after SGLT2i treatment and to compare them to DKA episodes due to other causes. METHODS: The medical records of the years 2018-2020 related to clinical and biochemical characteristics and to treatment of six patients with DKA due to SGLT2i were reviewed. They were compared to those of 12 patients with DKA due to other causes. RESULTS: On admission, the most common symptom was abdominal pain. Glucose levels (median, min-max) were lower in patients with SGLT2i-induced DKA compared to those with DKA due to other causes (229 (150-481) vs. 458.5 (332-695) mg/dl, p = 0.007), whereas no statistical difference was observed in HbA1c and in the severity of DKA (pH, HCO3, CO2, and anion gap). The duration of insulin infusion (41 (33-124) vs. 21.50 (11-32) h, p < 0.001) and the time required until DKA resolution (39 (31-120) vs. 19 (9-28) h, p < 0.001) were higher in patients with SGLT2i-induced DKA than those with DKA due to other causes. In addition, there were increased fluid requirements (14 (8-22.75) vs. 5.5 (2-24) L, p = 0.013) and longer hospitalization time (11 (6-22) vs. 5.5 (2-14) days, p = 0.024) in patients with SGLT2i-induced DKA. No statistically significant differences were observed in total intravenous insulin and potassium administration until DKA resolution. CONCLUSIONS: Patients with SGLT2i-induced DKA had lower serum glucose levels on admission and required increased fluid administration and longer time to recover from acidosis compared to patients with DKA from other causes.

Vitamin B12 and Folate Concentrations in Recent-onset Type 2 Diabetes and the Effect of Metformin Treatment.

CONTEXT: Vitamin B12 and folate deficiency are not only linked to hematological, neurological, and cardiovascular diseases, but are also associated with insulin resistance. Metformin can decrease vitamin B12 and folate concentrations. OBJECTIVE: To examine (1) effects of short-term metformin treatment on serum holotranscobalamin (holoTC) and folate and (2) their association with insulin sensitivity in recent-onset type 2 diabetes. DESIGN: This cross-sectional analysis comprised patients (known disease duration <12 months) on metformin monotherapy (MET, n = 123, 81 males, 53 ±â€…12 years) or nonpharmacological treatment (NPT, n = 126, 77 males, 54 ±â€…11 years) of the German Diabetes Study. MAIN OUTCOME MEASURES: HoloTC (enzyme-linked immunosorbent assay), cobalamin, and folate (electrochemiluminescence); beta-cell function and whole-body insulin sensitivity, measured during fasting (HOMA-B, HOMA-IR) and intravenous glucose tolerance tests combined with hyperinsulinemic-euglycemic clamp tests. RESULTS: HoloTC (105.4 [82.4, 128.3] vs 97 [79.7, 121.9] pmol/L) and folate concentrations (13.4 [9.3, 19.3] vs 12.7 [9.3, 22.0] nmol/L) were similar in both groups. Overall, holoTC was not associated with fasting or glucose-stimulated beta-cell function and insulin-stimulated glucose disposal. Cobalamin measurements yielded similar results in representative subgroups. In NPT but not MET, folate levels were inversely correlated with HOMA-IR (r = -0.239, P = .007). Folate levels did not relate to insulin sensitivity or insulin secretion in the whole cohort and in each group separately after adjustment for age, body mass index, and sex. CONCLUSIONS: Metformin does not affect circulating holoTC and folate concentrations in recent-onset type 2 diabetes, rendering monitoring of vitamin B12 and folate dispensable, at least during the first 6 months after diagnosis or initiation of metformin.