Heightened Cardiovascular Risk in Hypertension Associated With Renin‐Independent Aldosteronism Versus Renin‐Dependent Aldosteronism: A Collaborative Study

Background While both renin‐dependent and renin‐independent aldosterone secretion contribute to aldosteronism, their relative associations with cardiovascular disease (CVD) risk has not been investigated. Methods and Results A total of 2909 participants from the FOS (Framingham Offspring Study) with baseline, serum aldosterone concentration, and plasma renin concentration who attended the sixth examination cycle and were followed up until 2014 and who were free of CVD were included. We further recruited 2612 hypertensive participants from the CONPASS (Chongqing Primary Aldosteronism Study). Captopril challenge test was performed to confirm renin‐dependent or ‐independent aldosteronism in CONPASS. Among 1433 hypertensive subjects of FOS, when compared with those with serum aldosterone concentration <10 ng dL −1 (normal aldosterone), participants who had serum aldosterone concentration ≥10 ng dL −1 and plasma renin concentration ≤15 mIU L −1 (identified as renin‐independent aldosteronism) showed a higher risk of CVD (hazard ratio, 1.40 [95% CI, 1.08–1.82]), while those who had serum aldosterone concentration ≥10 ng dL −1 and plasma renin concentration >15 mIU L −1 (identified as renin‐dependent aldosteronism) showed an unchanged CVD risk. In CONPASS, renin‐independent aldosteronism carried a significantly higher risk of CVD than normal aldosterone (odds ratio, 2.57 [95% CI, 1.13–5.86]), while the CVD risk remained unchanged in renin‐dependent aldosteronism. Elevation of the urinary potassium‐to‐sodium excretion ratio, reflective of mineralocorticoid receptor activity, was only observed in participants with renin‐independent aldosteronism. Conclusions Among patients with hypertension, renin‐independent aldosteronism is more closely associated with CVD risk than renin‐dependent aldosteronism.

Leaky Gut Syndrome Is Associated with Endotoxemia and Serum (1→3)-β-D-Glucan in Severe Dengue Infection

The hallmark of severe dengue infection is the increased vascular permeability and hemodynamic alteration that might be associated with an intestinal permeability defect. However, the mechanisms underlying the gastrointestinal-related symptoms of dengue are not well characterized. A prospective observational study was conducted on patients with dengue who were categorized according to: (i) febrile versus critical phase and (ii) hospitalized patients with versus without the warning signs to evaluate the gut barrier using lactulose-to-mannitol excretion ratio (LEMR). Serum endotoxins, (1→3)-β-D-glucan (BG), and inflammatory parameters were measured. A total of 48 and 38 patients were enrolled in febrile illness and critical phase, respectively, while 22 and 64 patients presented with or without the warning signs, respectively. At enrollment, a positive LEMR test was found in 20 patients (91%) with warning signs, regardless of phase of infection. Likewise, serum endotoxins and BG, the indirect biomarkers for leaky gut, prominently increased in patients who developed severe dengue when compared with the non-severe dengue (endotoxins, 399.1 versus 143.4 pg/mL (p < 0.0001); BG, 123 versus 73.8 pg/mL (p = 0.016)). Modest impaired intestinal permeability occurred in dengue patients, particularly those with warning signs, and were associated with endotoxemia and elevated BG. Thus, leaky gut syndrome might be associated with severity of dengue infection.

Impaired Daytime Urinary Sodium Excretion Impacts Nighttime Blood Pressure and Nocturnal Dipping at Older Ages in the General Population

The circadian rhythm of urinary sodium excretion is related to the diurnal blood pressure regulation (BP) and the nocturnal dipping pattern. The renal sodium excretion expressed as daytime/nighttime ratio impacts BP, but a limited number of studies have investigated this topic to date. In this cross-sectional study, we aimed to investigate the impact of different daily patterns of sodium excretion (comparing low with high ratios) on BP and nocturnal dipping and to explore the relationship with age. Twenty-four-hour ambulatory BP monitoring and daytime and nighttime urinary sodium collections were used to assess 1062 subjects in Switzerland. Analyses were performed according to the day/night urinary sodium excretion ratio quartiles (Q1–Q4) and by age group (≤50 and ≥50 years). Subjects in Q1 can be considered low excretors of sodium during the daytime since the rate of sodium excretion during the daytime was 40% lower than that of subjects in Q4. Quartiles of the day/night urinary sodium excretion ratio showed that subjects in Q1 were 7 years older and had respectively 6 and 5 mmHg higher nighttime systolic and diastolic BP and a higher nocturnal dipping compared with subjects in Q4 (p-value ≤0.001). Associations found were significant only for subjects older than 50 years (all p < 0.05). The present results suggest that a decreased capacity to excrete sodium during daytime is more prevalent as age increases and that it impacts nighttime blood pressure and nocturnal dipping in older subjects.

SAT-377 Case Series of Ectopic Parathyroid Gland

The prevalence of mediastinal parathyroid adenoma is unknown. Embryological origin and more extensive aberrant migration of the parathyroid glands result in ectopic glands found in the mediastinum. We report herein 4 cases of ectopic parathyroid adenoma causing primary hyperparathyroidism from three public hospitals in MalaysiaCase 1.A 70 year old lady with underlying diabetes mellitus, hypertension, chronic immune thrombocytopenic purpura and liver cirrhosis presented with incidental asymptomatic hypercalcemia during an admission for pneumonia. Her blood results revealed high corrected calcium of 2.93 mmol/L (2.02-2.60) and a low phosphate of 0.66 (0.81-1.45) mmol/L with an unsuppressed intact parathyroid hormone (iPTH) of 14.56 pmol/L (1.6-6.9). She had an equivocal urinary calcium excretion ratio of 0.01. Her bone mineral density confirmed severe osteoporosis at distal radius and neck of femur with a Tscore of -3.6 and -3.1 respectively. A hyperfunctioning ectopic parathyroid gland was seen in the Technetium Sestamibi scan which corelates with a mediastinal lymphadenopathy on CECT. The largest node measured 1.6 x 1.2 cm. Parathyroid gland was confirmed on HPE of the video-assisted-thoracoscopic surgical (VATS) excision of the mediastinal mass. Intraoperative iPTH (ioPTH) serially reduced from 8.87 to 1.94 to 1.03 pmol/L and she maintained a serum calcium levels of 2.4 mmol/L post surgery. She did not require any calcium or vitamin D supplementation. Case 2. A 36 year old male presented with generalized body weakness secondary to hypokalemia. His calcium was 3.07 mmol/l, phosphate 0.64 mmol/l and iPTH 11.53 pmol/L. Increase Technetium uptake seen at mediastinum. Post operatively, calcium normalized and remained stable 1 year later. Case 3.47 year old female presented with acute gallstone pancreatitis complicated with a pancreatic pseudocyst. She was found to have hypercalcemia of 2.77 mmol/L, phosphate 0.70 mmol/l and iPTH 21.87 pmol/L. Sestamibi scan revealed hyperfunctiong parathyroid tissue posterior to the left thyroid lobe and in the mediastinum. She is awaiting surgery. Case 4.Another asymptomatic 47 year old male who has history of post Radioactive-iodine hypothyroidism had an incidental finding of serum calcium of 2.69-2.84 mmol/L, phosphate 0.71-0.91 mmol/L and iPTH 9.89 pmol/L with urinary calcium excretion ratio of 0.019. His Sestamibi scan showed uptake at the superior mediastinum. Ectopic parathyroid gland is rarely encountered. With the advent of Technetium-Sestamibi scintigraphy, ectopic parathyroid adenoma can be localized easily. However, surgery poses a challenge due the location of the adenoma which may occasionally be near large vascular structures in the mediastinum. The availability of intraoperative PTH aids the decision for surgical exploration and completion.

Changes in Conjunctival Hemodynamics Predict Albuminuria in Sickle Cell Nephropathy

Background: Albuminuria is an early manifestation of deterioration in renal function in subjects with sickle cell disease (SCD). Hyperfiltration may be an early mechanism for kidney damage in SCD. The purpose of the current study was to determine the association between conjunctival hemodynamics and albuminuria in SCD subjects with preserved glomerular filtration rate. Methods: Conjunctival microcirculation imaging was performed to measure conjunctival diameter and axial blood velocity (V) in 35 SCD and 10 healthy control subjects. Albuminuria, defined as albumin excretion ratio (AER), was obtained from the medical charts. Based on the 95% CI of conjunctival V in control subjects (0.40-0.60 mm/s), SCD subjects were allocated to 3 groups: V1 <0.40 mm/s (n = 7), V2 of 0.40-0.60 mm/s (n = 18) and V3 ≥0.60 mm/s (n = 10). Results: Mean log(AER) measurements in the V1, V2 and V3 groups were 1.08 ± 0.67, 1.39 ± 0.59 and 2.00 ± 0.91 mg/g creatinine, respectively, and followed a positive linear trend from the V1 to V3 groups (p = 0.01). By multivariate linear regression analysis, conjunctival V significantly correlated with albuminuria (p = 0.01) independent of age, blood pressure, α-thalassemia, hematocrit, white blood cell count and lactate dehydrogenase concentration. Conclusions: Increased conjunctival V is associated with albuminuria in SCD subjects. Assessment of conjunctival microvascular hemodynamics may improve our understanding of the pathophysiology and clinical management of sickle cell nephropathy.