Probability of sporadic lymphangioleiomyomatosis in women presenting with spontaneous pneumothorax.

BACKGROUND: Sporadic lymphangioleiomyomatosis (S-LAM) is a rare low-grade neoplasm of young women characterized by multiple pulmonary cysts leading to progressive dyspnea and recurrent spontaneous pneumothorax (SP). The diagnosis of S-LAM may be delayed by several years. To reduce this delay, chest computed tomography (CT) screening has been proposed to uncover cystic lung disease in women presenting with SP. However, the probability to discover S-LAM in this population has not been determined precisely. The aim of this study was to calculate the probability of finding S-LAM in women presenting with (a) SP, and (b) apparent primary SP (PSP) as first manifestation of S-LAM. METHODS: Calculations were made by applying the Bayes theorem to published epidemiological data on S-LAM, SP and PSP. Each term of the Bayes equation was determined by meta-analysis, and included: (1) the prevalence of S-LAM in the general female population, (2) the incidence rate of SP and PSP in the general female population, and (3) the incidence rate of SP and apparent PSP in women with S-LAM. RESULTS: The prevalence of S-LAM in the general female population was 3.03 per million (95% confidence interval 2.48, 3.62). The incidence rate of SP in the general female population was 9.54 (8.15, 11.17) per 100,000 person-years (p-y). The incidence rate of SP in women with S-LAM was 0.13 (0.08, 0.20). By combining these data in the Bayes theorem, the probability of finding S-LAM in women presenting with SP was 0.0036 (0.0025, 0.0051). For PSP, the incidence rate in the general female population was 2.70 (1.95, 3.74) per 100,000 p-y. The incidence rate of apparent PSP in women with S-LAM was 0.041 (0.030, 0.055). With the Bayes theorem, the probability of finding S-LAM in women presenting with apparent PSP as first disease manifestation was 0.0030 (0.0020, 0.0046). The number of CT scans to perform in women to find one case of S-LAM was 279 for SP and 331 for PSP. CONCLUSION: The probability of discovering S-LAM at chest CT in women presenting with apparent PSP as first disease manifestation was low (0.3%). Recommending chest CT screening in this population should be reconsidered.

Empagliflozin Changes Urine Supersaturation by Decreasing pH and Increasing Citrate.

Clinical Trial registry name and registration number: Empagliflozin and Renal Oxygenation in Healthy Volunteers (EMPA-REIN), NCT03093103.

Twenty-Four Hour Blood Pressure Response to Empagliflozin and Its Determinants in Normotensive Non-diabetic Subjects.

Background: Sodium-glucose co-transport 2 inhibitors (SGLT2i) lower blood pressure (BP) in normotensive subjects and in hypertensive and normotensive diabetic and non-diabetic patients. However, the mechanisms of these BP changes are not fully understood. Therefore, we examined the clinical and biochemical determinants of the BP response to empagliflozin based on 24-h ambulatory BP monitoring. Methods: In this post-hoc analysis of a double-blind, randomized, placebo-controlled study examining the renal effects of empagliflozin 10 mg vs. placebo in untreated normotensive non-diabetic subjects, the 1-month changes in 24 h ambulatory BP were analyzed in 39 subjects (13 placebo/26 empagliflozin) in regard to changes in biochemical and hormonal parameters. Results: At 1 month, empagliflozin 10 mg decreased 24-h systolic (SBP) and diastolic (DBP) BP significantly by -5 ± 7 mmHg (p < 0.001) and -2 ± 6 mmHg (p = 0.03). The effect on SBP and DBP was more pronounced during nighttime (resp. -6 ± 11 mmHg, p = 0.004; -4 ± 7 mmHg, p = 0.007). The main determinants of daytime and nighttime SBP and DBP responses were baseline BP levels (for daytime SBP: coefficient -0.5; adj. R2: 0.36; p = 0.0007; for night-time SBP: coefficient -0.6; adj. R2: 0.33; p = 0.001). Although empaglifozin induced significant biochemical changes, none correlated with blood pressure changes including urinary sodium, lithium, glucose and urate excretion and free water clearance. Plasma renin activity and plasma aldosterone levels increased significantly at 1 month suggesting plasma volume contraction, while plasma metanephrine and copeptin levels remained the same. Renal resistive indexes did not change with empagliflozin. Conclusion: SGLT2 inhibition lowers daytime and nighttime ambulatory systolic and diastolic BP in normotensive non-diabetic subjects. Twenty-four jour changes are pronounced and comparable to those described in diabetic or hypertensive subjects. Baseline ambulatory BP was the only identified determinant of systolic and diastolic BP response. This suggests that still other factors than sustained glycosuria or proximal sodium excretion may contribute to the resetting to lower blood pressure levels with SGLT2 inhibition. Clinical Trial Registration: [https://www.clinicaltrials.gov], identifier [NCT03093103].

Prevalence of Birt-Hogg-Dubé Syndrome Determined Through Epidemiological Data on Spontaneous Pneumothorax and Bayes Theorem.

Background: Birt-Hogg-Dubé syndrome (BHD) is a rare inherited disorder characterized by cutaneous fibrofolliculomas, multiple pulmonary cysts, recurrent spontaneous pneumothorax (SP), and renal tumors. More than 40 years after its description, the prevalence of BHD in the general population remains unknown. This study aimed at determining the prevalence of BHD by applying the Bayes theorem of conditional probability to epidemiological data on SP. Methods: We performed a meta-analysis of published data on: (1) the probability of having BHD among patients with apparent primary SP (4 studies), (2) the incidence rate of primary SP in the general population (9 studies), and (3) the probability of experiencing a SP in BHD (16 studies). Results were corrected for SP relapses, stratified by gender and year of study publication (before and after 2000), and computed with the Bayes equation. Results: The probability of having BHD among patients with apparent primary SP was 0.09 (95% confidence interval: 0.07, 0.11) or 9%. It was 0.20 (0.14, 0.27) in women and 0.05 (0.04, 0.07) in men. The incidence rate of primary SP in the general population was 8.69 (6.58, 11.46) per 100,000 person-years (p-y). It was 3.44 (2.36, 4.99) per 100,000 p-y in women and 13.96 (10.72, 18.18) per 100,000 p-y in men, and was about 2 times higher in studies published after 2000 than in those published before 2000. The probability of experiencing at least one SP among patients with BHD was 0.43 (0.31, 0.54) or 43%, without gender difference. By combining these data in the Bayes equation, we found a prevalence of BHD in the general population of 1.86 (1.16, 3.00) per million, with values of 1.86 (1.02, 3.39) per million in men, and 1.88 (0.97, 3.63) per million in women. Conclusion: The prevalence of BHD in the general population is about 2 cases per million, without difference between genders.

[Burnout among physicians : a new related reason ?] / Burnout des médecins : le dossier médical informatisé comme nouvelle cause.

Prevalence of burnout in physicians is increasing, affecting their health and satisfaction at work as well as quality and security of healthcare. Several causes have been identified, of which growing intensity of work, loss of meaning and feeling that healthcare structure reforms prevent one's job being done properly are the main reasons. New data shows an association between burnout and use of the yet widespread electronic health record. It has a proven impact on the multiple aspects of physician's work, and users' satisfaction is often mediocre. Hence, among the broad prevention field of physicians' burnout, specific measures related to the digital domain are needed.

La prévalence du burnout chez les médecins est en augmentation, affectant leur santé, leur satisfaction au travail ainsi que la qualité et la sécurité des soins. Diverses causes sont identifiées, les principales étant l'intensification du travail, le sentiment de perte de sens du travail et de ne pas faire son travail correctement dans un environnement (celui des organisations de soins) en changement. Des données récentes montrent aussi une association entre burnout et utilisation du dossier médical informatisé, désormais largement répandue. La satisfaction des utilisateurs est souvent médiocre et l'impact sur de multiples facettes du travail des médecins avéré. À la lumière de ces résultats, des actions de prévention spécifiques sont nécessaires, à intégrer dans le champ plus vaste de la prévention du burnout des médecins.

Acute and Chronic Effects of SGLT2 Inhibitor Empagliflozin on Renal Oxygenation and Blood Pressure Control in Nondiabetic Normotensive Subjects: A Randomized, Placebo-Controlled Trial.

Background The sodium/glucose cotransporter 2 inhibitor empagliflozin has cardiorenal protective properties through mechanisms beyond glucose control. In this study we assessed whether empagliflozin modifies renal oxygenation as a possible mechanism of renal protection, and determined the metabolic, renal, and hemodynamic effects of empagliflozin in nondiabetic subjects. Methods and Results In this double-blind, randomized, placebo-controlled study, 45 healthy volunteers underwent blood and urine sampling, renal ultrasound, and blood-oxygenation-level-dependent magnetic resonance imaging before and 180 minutes after administration of 10 mg empagliflozin (n=30) or placebo (n=15). These examinations were repeated after 1 month of daily intake. Cortical and medullary renal oxygenation were not affected by the acute or chronic administration of empagliflozin, as determined by 148 renal blood-oxygenation-level-dependent magnetic resonance imaging examinations. Empagliflozin increased glucosuria (24-hour glucosuria at 1 month: +50.1±16.3 g). The acute decrease in proximal sodium reabsorption, as determined by endogenous fractional excretion of lithium (-34.6% versus placebo), was compensated at 1 month by a rise in plasma renin activity (+28.6%) and aldosterone (+55.7%). The 24-hour systolic and diastolic ambulatory blood pressures decreased significantly after 1 month of empagliflozin administration (-5.1 and -2.0 mm Hg, respectively). Serum uric acid levels decreased (-28.4%), hemoglobin increased (+1.7%), and erythropoietin remained the same. Conclusions Empagliflozin has a rapid and significant effect on tubular function, with sustained glucosuria and transient natriuresis in nondiabetic normotensive subjects. These effects favor blood pressure reduction. No acute or sustained changes were found in renal cortical or medullary tissue oxygenation. It remains to be determined whether this is the case in nondiabetic or diabetic patients with congestive heart failure or kidney disease. REGISTRATION: URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT03093103.

Effects of the SGLT-2 Inhibitor Empagliflozin on Renal Tissue Oxygenation in Non-Diabetic Subjects: A Randomized, Double-Blind, Placebo-Controlled Study Protocol.

INTRODUCTION: Empagliflozin is an SGLT-2 inhibitor (SGLT-2i) which belongs to a new class of hypoglycemic drugs with the unique property of decreasing blood glucose independently from insulin, through an increase in glycosuria. In addition to decreasing cardiovascular morbidity and mortality, empagliflozin has nephroprotective properties in high cardiovascular risk patients with type 2 diabetes. Decreased hyperfiltration and shifting towards more favorable renal fuel energetics with improved renal oxygenation may explain some of these properties. With this study, we propose to explore the effects of empagliflozin on renal tissue oxygenation using blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI). METHODS: This is a double-blind, randomized, placebo-controlled study examining the acute and chronic renal effects of empagliflozin 10 mg. The primary outcome is the effects of empagliflozin on renal tissue oxygenation as measured by BOLD-MRI. The secondary outcomes include the effects of empagliflozin on tubular function, 24 h blood pressure control, and the influence of body mass index (BMI) on the renal response to empagliflozin. Fifteen normal weight, 15 overweight, and 15 obese non-diabetic subjects (men and women) will be recruited. Each participant will undergo 24 h urine collections and blood pressure measurements on day - 1, followed by an investigation day at the study center with blood and urine sampling and renal BOLD-MRI measurements before and 180 min after the administration of 10 mg empagliflozin or placebo. This sequence of measurements will be repeated after 1 month of a daily empagliflozin or placebo intake. To investigate renal oxygenation, the renal cortical and medullary R2*, as a marker of oxygenation, will be assessed by BOLD-MRI under standardized hydration conditions: the higher R2*, the lower oxygenation. CONCLUSION: SGLT-2 inhibitors have a profound effect on renal physiology. This is an important study that will explore for the first time whether inhibiting SGLT-2 with empagliflozin in healthy volunteers affects renal tissue oxygenation as determined by BOLD-MRI. FUNDING: Boehringer Ingelheim Pharma GmbH & Co. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT03093103.

Comparative Effect of a Renin Inhibitor and a Thiazide Diuretic on Renal Tissue Oxygenation in Hypertensive Patients.

BACKGROUND/AIMS: The purpose of the present study was to compare the direct renin inhibitor aliskiren to the diuretic hydrochlorothiazide (HCTZ) in their ability to modulate renal tissue oxygenation in hypertensive patients. METHODS: 24 patients were enrolled in this randomized prospective study and 20 completed the protocol. Patients were randomly assigned to receive either aliskiren 150-300 mg/d or HCTZ 12.5 - 25 mg/d for 8 weeks. Renal oxygenation was measured by BOLD-MRI at weeks 0 and 8. BOLD-MRI was also performed before and after an i.v. injection of 20 mg furosemide at week 0 and at week 8. BOLD-MRI data were analyzed by measuring the oxygenation in 12 computed layers of the kidney enabling to asses renal oxygenation according to the depth within the kidney and by the classical method of regions of interest (ROI). RESULTS: The classical ROI analysis of the data showed no difference between the groups at week 8. The analysis of renal oxygenation according to the 12 layers method shows no significant difference between aliskiren and HCTZ at week 8 before administration of furosemide. However, within group analyses show that aliskiren slightly but not significantly increased oxygenation in the cortex and decreased medullary oxygenation whereas HCTZ induced a significant overall decrease in renal tissue oxygenation. With the same method of analysis we observed that the response to furosemide was unchanged in the HCTZ group at week 8 but was characterized by an increase in both cortical and medullary oxygenation in aliskiren-treated patients. Patients responding to aliskiren and HCTZ by a fall in systolic blood pressure of >10 mmHg improved their renal tissue oxygenation when compared to non-responders. CONCLUSION: With the classical method of evaluation using regions no difference were found between aliskiren and HCTZ on renal tissue oxygenation after 8 weeks. In contrast, with our new method that takes into account the entire kidney, within group analyses show that aliskiren slightly increases cortical and medullary renal tissue oxygenation in hypertensive patients whereas HCTZ decreases significantly renal oxygenation at trough.

Furosemide stimulation of parathormone in humans: role of the calcium-sensing receptor and the renin-angiotensin system.

Interactions between sodium and calcium regulating systems are poorly characterized but clinically important. Parathyroid hormone (PTH) levels are increased shortly after furosemide treatment by an unknown mechanism, and this effect is blunted by the previous administration of a calcimimetic in animal studies. Here, we explored further the possible underlying mechanisms of this observation in a randomized crossover placebo-controlled study performed in 18 human males. Volunteers took either cinacalcet (60 mg) or placebo and received a 20 mg furosemide injection 3 h later. Plasma samples were collected at 15-min intervals and analyzed for intact PTH, calcium, sodium, potassium, magnesium, phosphate, plasma renin activity (PRA), and aldosterone up to 6 h after furosemide injection. Urinary electrolyte excretion was also monitored. Subjects under placebo presented a sharp increase in PTH levels after furosemide injection. In the presence of cinacalcet, PTH levels were suppressed and marginal increase of PTH was observed. No significant changes in electrolytes and urinary excretion were identified that could explain the furosemide-induced increase in PTH levels. PRA and aldosterone were stimulated by furosemide injection but were not affected by previous cinacalcet ingestion. Expression of NKCC1, but not NKCC2, was found in parathyroid tissue. In conclusion, our results indicate that furosemide acutely stimulates PTH secretion in the absence of any detectable electrolyte changes in healthy adults. A possible direct effect of furosemide on parathyroid gland needs further studies.

Determinants of renal tissue oxygenation as measured with BOLD-MRI in chronic kidney disease and hypertension in humans.

Experimentally renal tissue hypoxia appears to play an important role in the pathogenesis of chronic kidney disease (CKD) and arterial hypertension (AHT). In this study we measured renal tissue oxygenation and its determinants in humans using blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) under standardized hydration conditions. Four coronal slices were selected, and a multi gradient echo sequence was used to acquire T2* weighted images. The mean cortical and medullary R2* values ( = 1/T2*) were calculated before and after administration of IV furosemide, a low R2* indicating a high tissue oxygenation. We studied 195 subjects (95 CKD, 58 treated AHT, and 42 healthy controls). Mean cortical R2 and medullary R2* were not significantly different between the groups at baseline. In stimulated conditions (furosemide injection), the decrease in R2* was significantly blunted in patients with CKD and AHT. In multivariate linear regression analyses, neither cortical nor medullary R2* were associated with eGFR or blood pressure, but cortical R2* correlated positively with male gender, blood glucose and uric acid levels. In conclusion, our data show that kidney oxygenation is tightly regulated in CKD and hypertensive patients at rest. However, the metabolic response to acute changes in sodium transport is altered in CKD and in AHT, despite preserved renal function in the latter group. This suggests the presence of early renal metabolic alterations in hypertension. The correlations between cortical R2* values, male gender, glycemia and uric acid levels suggest that these factors interfere with the regulation of renal tissue oxygenation.

[Primary hyperaldosteronism with adrenal adenoma or hyperplasia: surgical case or not?]. / Hyperaldostéronisme primaire sur adénome ou hyperplasie de la surrénale: opérer ou non?

Primary hyperaldosteronism is one of the most frequent causes of secondary hypertension. Cardiovascular morbimortality is higher than in essential hypertonic and justifies diagnostic and specific treatment of this pathology. Therapeutic choice depends of health and desire of the patient. It is either medical with mineralocorticoid receptor antagonists, or surgical through adrenalectomy. In this case, a pre-surgery exam including a radiologic examination and a venous adrenal catheterism has to be done. Surgery allows a normalisation of kaliema and a blood pressure decrease in 50 to 88% of the patients. Beyond them, 30% are able to stop entirely their medication. Both therapeutic choices decrease cardiovascular risks equally if blood pressure is controlled.

[Not Available]. / La vitesse de l'onde de pouls et la pression artérielle centrale devraient-elles être mesurées chez les patients hypertendus?

Diagnosis and treatment of arterial hypertension are essential in order to reduce the mortality and the morbidity associated with this condition. The decision to treat hypertension is often based on serial office blood pressure measurements, but new non-invasive measurements such as pulse wave velocity or central blood pressure measurement using pulse wave analysis can be useful to assess the cardiovascular risk with more precision. Indeed, pulse vawe velocity, which is a marker of arterial stiffness, is an independent risk factor for future cardiovascular events. Non-pharmacological and pharmacological therapies can affect both pulse wave velocity and central pressure. However, more studies are needed in order to determine if these measurements can be use as surrogate marker of cardiovascular disease.

Renal tissue oxygenation in essential hypertension and chronic kidney disease.

Animal studies suggest that renal tissue hypoxia plays an important role in the development of renal damage in hypertension and renal diseases, yet human data were scarce due to the lack of noninvasive methods. Over the last decade, blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI), detecting deoxyhemoglobin in hypoxic renal tissue, has become a powerful tool to assess kidney oxygenation noninvasively in humans. This paper provides an overview of BOLD-MRI studies performed in patients suffering from essential hypertension or chronic kidney disease (CKD). In line with animal studies, acute changes in cortical and medullary oxygenation have been observed after the administration of medication (furosemide, blockers of the renin-angiotensin system) or alterations in sodium intake in these patient groups, underlining the important role of renal sodium handling in kidney oxygenation. In contrast, no BOLD-MRI studies have convincingly demonstrated that renal oxygenation is chronically reduced in essential hypertension or in CKD or chronically altered after long-term medication intake. More studies are required to clarify this discrepancy and to further unravel the role of renal oxygenation in the development and progression of essential hypertension and CKD in humans.

Blockade of the renin-angiotensin system and renal tissue oxygenation as measured with BOLD-MRI in patients with type 2 diabetes.

AIM: To assess whether blockade of the renin-angiotensin system (RAS), a recognized strategy to prevent the progression of diabetic nephropathy, affects renal tissue oxygenation in type 2 diabetes mellitus (T2DM) patients. METHODS: Prospective randomized 2-way cross over study; T2DM patients with (micro)albuminuria and/or hypertension underwent blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) at baseline, after one month of enalapril (20 mgqd), and after one month of candesartan (16 mgqd). Each BOLD-MRI was performed before and after the administration of furosemide. The mean R2* (=1/T2*) values in the medulla and cortex were calculated, a low R2* indicating high tissue oxygenation. RESULTS: Twelve patients (mean age: 60 ± 11 years, eGFR: 62 ± 22 ml/min/1.73 m(2)) completed the study. Neither chronic enalapril nor candesartan intake modified renal cortical or medullary R2* levels. Furosemide significantly decreased cortical and medullary R2* levels suggesting a transient increase in renal oxygenation. Medullary R2* levels correlated positively with urinary sodium excretion and systemic blood pressure, suggesting lower renal oxygenation at higher dietary sodium intake and blood pressure; cortical R2* levels correlated positively with glycemia and HbA1c. CONCLUSION: RAS blockade does not seem to increase renal tissue oxygenation in T2DM hypertensive patients. The response to furosemide and the association with 24 h urinary sodium excretion emphasize the crucial role of renal sodium handling as one of the main determinants of renal tissue oxygenation.