Susceptibility to recombinant SARS-CoV-2 spike protein entry in the lungs of high-fat diet-induced obese mice.

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Obesity is a major risk factor for the development of COVID-19. Angiotensin-converting enzyme 2 (ACE2) is an essential receptor for cell entry of SARS-CoV-2. The receptor-binding domain of the S1 subunit (S1-RBD protein) in the SARS-CoV-2 spike glycoprotein binds to ACE2 on host cells, through which the virus enters several organs, including the lungs. Considering these findings, recombinant ACE2 might be utilized as a decoy protein to attenuate SARS-CoV-2 infection. Here, we examined whether obesity increases ACE2 expression in the lungs and whether recombinant ACE2 administration diminishes the entry of S1-RBD protein into lung cells. We observed that high-fat diet-induced obesity promoted ACE2 expression in the lungs by increasing serum levels of LPS derived from the intestine. S1-RBD protein entered the lungs specifically through ACE2 expressed in host lungs and that the administration of recombinant ACE2 attenuated this entry. We conclude that obesity makes hosts susceptible to recombinant SARS-CoV-2 spike proteins due to elevated ACE2 expression in lungs, and this model of administering S1-RBD protein can be applied to new COVID-19 treatments.

Urinary podocyte markers of disease activity, therapeutic efficacy, and long-term outcomes in acute and chronic kidney diseases.

A critical degree of podocyte depletion causes glomerulosclerosis, and persistent podocyte loss in glomerular diseases drives the progression to end-stage kidney disease. The extent of podocyte injury at a point in time can be histologically assessed by measuring podocyte number, size, and density ("Biopsy podometrics"). However, repeated invasive renal biopsies are associated with increased risk and cost. A noninvasive method for assessing podocyte injury and depletion is required. Albuminuria and proteinuria do not always correlate with disease activity. Podocytes are located on the urinary space side of the glomerular basement membrane, and as they undergo stress or detach, their products can be identified in urine. This raises the possibility that urinary podocyte products can serve as clinically useful markers for monitoring glomerular disease activity and progression ("Urinary podometrics"). We previously reported that urinary sediment podocyte mRNA reflects disease activity in both animal models and human glomerular diseases. This includes diabetes and hypertension which together account for 60% of new-onset dialysis induction patients. Improving approaches to preventing progression is an urgent priority for the renal community. Sufficient evidence now exists to indicate that monitoring urinary podocyte markers could serve as a useful adjunctive strategy for determining the level of current disease activity and response to therapy in progressive glomerular diseases.

Development and validation of a machine learning model to predict time to renal replacement therapy in patients with chronic kidney disease.

BACKGROUND: Predicting time to renal replacement therapy (RRT) is important in patients at high risk for end-stage kidney disease. We developed and validated machine learning models for predicting the time to RRT and compared its accuracy with conventional prediction methods that uses the rate of estimated glomerular filtration rate (eGFR) decline. METHODS: Data of adult chronic kidney disease (CKD) patients who underwent hemodialysis at Oita University Hospital from April 2016 to March 2021 were extracted from electronic medical records (N = 135). A new machine learning predictor was compared with the established prediction method that uses the eGFR decline rate and the accuracy of the prediction models was determined using the coefficient of determination (R2). The data were preprocessed and split into training and validation datasets. We created multiple machine learning models using the training data and evaluated their accuracy using validation data. Furthermore, we predicted the time to RRT using a conventional prediction method that uses the eGFR decline rate for patients who had measured eGFR three or more times in two years and evaluated its accuracy. RESULTS: The least absolute shrinkage and selection operator regression model exhibited moderate accuracy with an R2 of 0.60. By contrast, the conventional prediction method was found to be extremely low with an R2 of -17.1. CONCLUSIONS: The significance of this study is that it shows that machine learning can predict time to RRT moderately well with continuous values from data at a single time point. This approach outperforms the conventional prediction method that uses eGFR time series data and presents new avenues for CKD treatment.

Comprehensive lipidomics of lupus-prone mice using LC-MS/MS identifies the reduction of palmitoylethanolamide that suppresses TLR9-mediated inflammation.

Lipid mediators are known to play crucial roles not only in the onset of the inflammatory response but also in the induction of resolution of inflammation. Here, we report that palmitoylethanolamide (PEA), an endogenous N-acylethanolamine, can suppress the inflammation induced by Toll-like receptor (TLR) signaling both in vitro and in vivo. PEA was found to be significantly reduced in the serum and spleen of lupus-prone MRL/lpr mice analyzed by lipidomics. PEA suppressed pro-inflammatory cytokine production in a mouse macrophage cell line stimulated with TLR ligands such as lipopolysaccharide, peptidoglycan, poly (I:C), imiquimod, and CpG-ODN. PEA also inhibited both mRNA and protein levels of IL-6 in bone marrow-derived dendritic cells (BMDCs) and B cells stimulated with CpG-ODN. Augmentation of cell surface CD86 and CD40 on BMDCs and B cells, IgM production, and cell proliferation of B cells in response to CpG-ODN were attenuated by PEA. Moreover, PEA treatment significantly reduced mortality and serum IL-6 levels in mice injected with CpG-ODN plus D-galactosamine. Taken together, PEA ameliorates inflammation induced by TLR signaling, which could be a novel therapeutic target for inflammatory disorders.

Rationale and design of an investigator-initiated, multicenter, prospective, placebo-controlled, double-blind, randomized trial to evaluate the effects of finerenone on vascular stiffness and cardiorenal biomarkers in type 2 diabetes and chronic kidney disease (FIVE-STAR).

BACKGROUND: The overactivation of mineralocorticoid receptor (MR) plays a key pathological role in the progression of cardiovascular and renal diseases by promoting pro-inflammatory and pro-fibrotic signaling. Recently, it has been found that finerenone, a novel nonsteroidal selective MR antagonist, can robustly improve cardiorenal outcomes in patients with type 2 diabetes (T2D) and a wide spectrum of chronic kidney disease (CKD). However, the mechanisms underlying the cardiorenal benefits of finerenone are poorly understood. Further, whether the clinical benefits are mediated by an improvement in vascular stiffness is not confirmed. Therefore, the current study aims to evaluate the effects of finerenone on vascular stiffness as assessed using cardio ankle vascular index (CAVI) and relevant cardiorenal biomarkers in patients with T2D and CKD. METHODS: The Effects of Finerenone on Vascular Stiffness and Cardiorenal Biomarkers in Type 2 Diabetes and Chronic Kidney Disease (FIVE-STAR) is an ongoing, investigator-initiated, multicenter, prospective, placebo-controlled, double-blind, randomized clinical trial in Japan. Its target sample size is 100 subjects. Recruitment will be performed from September 2023 to July 2024. After obtaining informed consent, eligible participants with T2D and CKD (25 mL/min/1.73 m2 ≤ estimated glomerular filtration ratio [eGFR] < 90 mL/min/1.73 m2 and 30 mg/g Cr ≤ urinary albumin-to-creatinine ratio [UACR] < 3500 mg/g Cr) will be equally randomized to receive 24-week treatment with either finerenone (starting dose at 10 mg once daily in participants with a baseline eGFR < 60 mL/min/1.73 m2 or at 20 mg once daily in those with a baseline eGFR ≥ 60 mL/min/1.73 m2) or dose-matched placebo. The primary endpoint is the change from baseline in CAVI at 24 weeks. The secondary endpoints are changes from baseline in UACR at 12 and 24 weeks and relevant serum and urinary biomarkers at 24 weeks. As an exploratory endpoint, proteomic analysis using the Olink® Target 96 panels will be also performed. DISCUSSION: FIVE-STAR is the first trial evaluating the therapeutic impact of finerenone on vascular stiffness and relevant cardiorenal biomarkers in patients with T2D and CKD. This study will provide mechanistic insights on the clinical benefits of finerenone based on recent cardiovascular and renal outcome trials. Trial registration Unique Trial Number, NCT05887817 ( https://clinicaltrials.gov/ct2/show/NCT05887817 ) and jRCTs021230011 ( https://jrct.niph.go.jp/latest-detail/jRCTs021230011 ).

Pitfalls in the diagnosis and treatment of a hypertensive patient with unilateral primary aldosteronism and contralateral pheochromocytoma: a case report.

BACKGROUND: Primary aldosteronism (PA) is a common cause of secondary hypertension, whereas pheochromocytoma is a rare cause of it. Thus, concomitant PA and pheochromocytoma is a very rare condition. CASE PRESENTATION: A 52-year-old woman was admitted to our hospital with suspected PA based on the presence of hypertension, spontaneous hypokalemia, and a high aldosterone-to-renin ratio. She had no catecholamine excess symptoms other than hypertension. Abdominal computed tomography (CT) showed a right lipid-rich adrenal mass and a left lipid-poor adrenal mass. PA was diagnosed by the captopril challenge test. The 24-h urinary fractionated metanephrines were slightly elevated. Adrenal vein sampling (AVS) confirmed that the right adrenal gland was responsible for aldosterone hypersecretion. Medical therapy with eplerenone was started because the patient refused surgery. Five years later, she requested surgery for PA. The second AVS confirmed right unilateral hyperaldosteronism, as expected. Repeated abdominal CT showed the enlargement of the left adrenal mass. The 24-h urinary fractionated metanephrines had risen to the diagnostic level. 123I- metaiodobenzylguanidine (MIBG) scintigraphy showed a marked tracer uptake in the left adrenal mass with no metastatic lesion. After preoperative management with α-blockade, laparoscopic left partial adrenalectomy was performed. Immunohistochemical examination of the tumor showed chromogranin A positivity leading to the diagnosis of left pheochromocytoma. CONCLUSIONS: We report an extremely rare case of concomitant unilateral PA and contralateral pheochromocytoma. When diagnosing unilateral PA by AVS, especially in cases with a lipid-poor adrenal mass, clinicians should rule out the possibility of the presence of pheochromocytoma before proceeding to undergo unilateral adrenalectomy. Although there is no standard treatment for this rare condition, it is essential to select personalized treatment from the perspective of conserving the adrenal gland.

Comparison and commutability study between standardized liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) and chemiluminescent enzyme immunoassay for aldosterone measurement in blood.

A commutability confirmation test for the blood aldosterone measurement was performed on liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) as a designated comparison method (DCM) and four chemiluminescent enzyme immunoassay (CLEIA) measurement procedures based on metrological traceability. A conventional radioimmunoassay (RIA) and two measurement procedures of CLEIA which obtains RIA equivalent values were also compared. The relationship between the DCM value and the CLEIA value with respect to 120 pg/mL of the RIA value, which is the screening criterion of primary aldosteronism (PA) was clarified. For the correlation test, 75 samples of patient serum and plasma were used. Regression analysis revealed that the standardized LC-MS/MS and four CLEIA measurement procedures were in good agreement. This is the effect of measurement specificity and calibration using by certified reference material (CRM). The median of the LC-MS/MS corresponding to 120 pg/mL of RIA was 48.5 pg/mL. In the mean of standardized four CLEIA values corresponding to the 48.5 pg/mL of LC-MS/MS value was 47.51 pg/mL and the standard deviation (SD) was 2.93 pg/mL. However, the correlation between the RIA value and the RIA equivalent of the two measurement procedures by CLEIA differed depending on the measurement procedure. This is due to the influence of RIA measurement performance. Standardized CLEIA measurements are suitable for routine measurement procedure. When converting the LC-MS/MS equivalent value by the standardized CLEIA to the conventional RIA value, it is necessary to use the conversion formula.

Japan Endocrine Society clinical practice guideline for the diagnosis and management of primary aldosteronism 2021.

Primary aldosteronism (PA) is associated with higher cardiovascular morbidity and mortality rates than essential hypertension. The Japan Endocrine Society (JES) has developed an updated guideline for PA, based on the evidence, especially from Japan. We should preferentially screen hypertensive patients with a high prevalence of PA with aldosterone to renin ratio ≥200 and plasma aldosterone concentrations (PAC) ≥60 pg/mL as a cut-off of positive results. While we should confirm excess aldosterone secretion by one positive confirmatory test, we could bypass patients with typical PA findings. Since PAC became lower due to a change in assay methods from radioimmunoassay to chemiluminescent enzyme immunoassay, borderline ranges were set for screening and confirmatory tests and provisionally designated as positive. We recommend individualized medicine for those in the borderline range for the next step. We recommend evaluating cortisol co-secretion in patients with adrenal macroadenomas. Although we recommend adrenal venous sampling for lateralization before adrenalectomy, we should carefully select patients rather than all patients, and we suggest bypassing in young patients with typical PA findings. A selectivity index ≥5 and a lateralization index >4 after adrenocorticotropic hormone stimulation defines successful catheterization and unilateral subtype diagnosis. We recommend adrenalectomy for unilateral PA and mineralocorticoid receptor antagonists for bilateral PA. Systematic as well as individualized clinical practice is always warranted. This JES guideline 2021 provides updated rational evidence and recommendations for the clinical practice of PA, leading to improved quality of the clinical practice of hypertension.

Metabolic Reprogramming Commits Differentiation of Human CD27+IgD+ B Cells to Plasmablasts or CD27-IgD- Cells.

B cells play a crucial role in the pathogenesis of autoimmune diseases, such as systemic lupus erythematosus (SLE). However, the relevance of the metabolic pathway in the differentiation of human B cell subsets remains unknown. In this article, we show that the combination of CpG/TLR9 and IFN-α markedly induced the differentiation of CD27+IgD+ unswitched memory B cells into CD27hiCD38hi plasmablasts. The response was accompanied by mammalian target of rapamycin complex 1 (mTORC1) activation and increased lactate production, indicating a shift to glycolysis. However, CpG alone induced the differentiation of unswitched memory B cells into CD27-IgD- memory B cells with high cytokine production, but such differentiation was suppressed by IFN-α. AMP-activated protein kinase activation enhanced the differentiation to CD27-IgD- B cells, but it attenuated mTORC1 activation and differentiation into plasmablasts. High mTORC1 activation was noted in CD19+ B cells of patients with SLE and correlated with plasmablast differentiation and disease activity. Taken together, differential metabolic reprogramming commits the differentiation of human unswitched memory B cells into plasmablasts (the combination of CpG and IFN-α amplifies mTORC1-glycolysis pathways) or CD27-IgD- memory B cells (CpG alone amplifies the AMP-activated protein kinase pathway). The former metabolic pathway may play a pivotal role in SLE.

Relationships between computed tomography-assessed density, abdominal fat volume, and glucose metabolism after sleeve gastrectomy in Japanese patients with obesity.

In this study, we investigated the relationships between body weight (BW), computed tomography (CT)-assessed abdominal adipose tissue, and the glycemic metabolic profile in obese Japanese patients following laparoscopic sleeve gastrectomy (LSG). This study analyzed adipose tissue compartments using CT methods before and 1 year after LSG. Thirty obese patients were studied, and variables measured included visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), density of VAT (VAT-D), and density of SAT (SAT-D). We also examined the parameters in patients according to whether they had type-2 diabetes (T2DM). LSG induced significant losses in BW, SAT, and VAT after LSG. Additionally, SAT-D and VAT-D both increased and fasting plasma glucose (FPG) and HbA1c, but not C-peptide, decreased after surgery. ΔSAT and ΔVAT were positively related, and ΔSAT-D and ΔVAT-D were negatively related to ΔBW and/or FPG. Furthermore, a multivariate regression model showed that total BW loss (TBWL) was closely related to ΔSAT (ß = 0.84; p < 0.001) and ΔVAT-D (ß = -0.45; p < 0.05) and improvement of FPG was related to ΔVAT (ß = 0.61; p < 0.05) after LSG. Finally, ΔFPG was correlated with ΔVAT in 16 T2DM patients (r = 0.58; p < 0.05) but not in non-T2DM patients. TBWL was related to ΔSAT and ΔVAT-D, and improvement of FPG was related to ΔVAT in obese Japanese patients after LSG.

l-Leucine influx through Slc7a5 regulates inflammatory responses of human B cells via mammalian target of rapamycin complex 1 signaling.

Objectives: Increasing evidence has revealed the close correlation between immune cell functions and their intracellular metabolism. Mammalian target of rapamycin complex 1 (mTORC1) is the important metabolism-modulating signal that regulates cellular activities. In certain types of cell, it is known that mTORC1 activation depends on influx of l-leucine through an amino acid transporter, Slc7a5. In B cells, however, the expression and the role of Slc7a5 have never been investigated. Methods: CD19+ B cells were obtained from peripheral blood of healthy adults and stimulated by a toll-like receptor 9 ligand, CpG oligodeoxynucleotides. The expression of Slc7a5 and l-leucine uptake were evaluated by RT-PCR, flow cytometry and radioisotope assay. Then the effect of Slc7a5 inhibition on mTORC1 activity, plasmablast differentiation and production of IgG and inflammatory cytokines were analyzed. Results: CpG stimulation significantly induced the expression of Slc7a5 in B cells, resulting in l-leucine influx. Furthermore, inhibition of Slc7a5 abrogated mTORC1 activation, plasmablast differentiation, and production of IgG and inflammatory cytokines in CpG-stimulated B cells. Conclusion: l-leucine influx through Slc7a5 critically regulates mTORC1 activity and the immunological responses of human B cells. Slc7a5-mTORC1 pathway may provide a novel therapeutic strategy for autoimmune diseases.

Accuracy of adrenal computed tomography in predicting the unilateral subtype in young patients with hypokalaemia and elevation of aldosterone in primary aldosteronism.

CONTEXT: The current Endocrine Society Guideline suggests that patients aged <35 years with marked primary aldosteronism (PA) and unilateral adrenal lesions on adrenal computed tomography (CT) scan may not need adrenal vein sampling (AVS) before proceeding to unilateral adrenalectomy. This suggestion is, however, based on the data from only one report in the literature. OBJECTIVE: We sought to determine the accuracy of CT findings in young PA patients who had unilateral adrenal disease on CT with hypokalaemia and elevation of aldosterone. DESIGN AND PATIENTS: We retrospectively studied 358 PA patients (n = 30, aged <35 years; n = 39, aged 35-40 years; n = 289, aged ≥40 years) with hypokalaemia and elevation of aldosterone and unilateral disease on CT who had successful AVS. MAIN OUTCOME MEASURE: Accuracy of CT findings is determined by AVS findings and/or surgical outcomes in patients aged <35 years. RESULTS: Concordance of the diagnosis between CT and AVS was 90% (27/30) in patients aged <35 years, 79% (31/39) in patients aged 35-40 years and 69% (198/289) in those aged ≥40 years (trend for P < .01). Surgical benefit was confirmed in three patients aged <35 years and in three patients aged 35-40 years with the available surgical data who had discordance between CT and AVS findings. Collectively, the diagnostic accuracy of CT findings was 100% (30/30) if aged <35 years and 87% (34/39) if aged 35-40 years. CONCLUSION: Primary aldosteronism patients aged <35 years with hypokalaemia and elevation of aldosterone and unilateral disease on adrenal CT could be spared AVS.

Role of spleen-derived IL-10 in prevention of systemic low-grade inflammation by obesity [Review].

Obesity can be associated with systemic low-grade inflammation that leads to obesity-related metabolic disorders. Recent studies raise the possibility that the inflammation in hypothalamus, liver and white adipose tissue (WAT) contributes to the pathogenesis of diet-induced obesity. We focus on the role of interleukin (IL)-10, an anti-inflammatory cytokine produced from spleen in obesity because it is indicated that obesity decreases the expression of pro-inflammatory cytokines in spleen. Obesity results in decrease of IL-10 synthesis from spleen, probably due to reduction of B-cells expression by promoting oxidative stress and apoptosis in spleen. Splenectomy (SPX) aggravates the inflammatory response in hypothalamus, liver and WAT. These SPX-induced alterations are inhibited by systemic administration of IL-10. Moreover, in IL-10 deficiency, SPX had little effect on the inflammatory responses in these multiple organs. We show the role of spleen-derived IL-10 on inflammatory responses in obesity.

High Glucose Stimulates Mineralocorticoid Receptor Transcriptional Activity Through the Protein Kinase C ß Signaling.

Activation of mineralocorticoid receptor (MR) is shown in resistant hypertension including diabetes mellitus. Although protein kinase C (PKC) signaling is involved in the pathogenesis of diabetic complications, an association between PKC and MR is not known. Activation of PKCα and PKCß by TPA (12-O-Tetradecanoylphorbol 13-acetate) increased MR proteins and its transcriptional activities in HEK293-MR cells. In contrast, a high glucose condition resulted in PKCß but not PKCα activation, which is associated with elevation of MR protein levels and MR transcriptional activities. Reduction of endogenous PKCß by siRNA decreased those levels. Interestingly, high glucose did not affect MR mRNA levels, but rather decreased ubiquitination of MR proteins. In db/db mice kidneys, levels of phosphorylated PKCß2, MR and Sgk-1 proteins were elevated, and the administration of PKC inhibitor reversed these changes compared to db/+ mice. These data suggest that high glucose stimulates PKCß signaling, which leads to MR stabilization and its transcriptional activities.

Large-vessel involvement in granulomatosis with polyangiitis successfully treated with rituximab: A case report and literature review.

Granulomatosis with polyangiitis (GPA) is primary necrotizing vasculitis, which predominantly affects small to medium vessels. Herein, we describe a case of a 60-year-old female with GPA who developed inflammatory wall thickening localized in the aortic arch, upper abdominal aorta, and pulmonary artery. The wall thickening in the large vessels and other GPA lesions such as lung nodules and orbital mass had failed to respond to high-dose glucocorticoids combined with cyclophosphamide; however, all were successfully treated with rituximab. Our literature review identified 24 cases of large-vessel involvement associated with GPA. Luminal stenosis, occlusion, or wall thickening were observed in 8, periaortitis in 11, and aneurysms in 5 cases. The most commonly affected vessel was the abdominal aorta (12 cases), followed by the thoracic aorta (6 cases), subclavian artery (4 cases), and internal carotid artery (4 cases). Glucocorticoids were used in 23 cases, 20 of which received combination therapy with cyclophosphamide. Surgical or endovascular therapies were performed in 10 cases with aneurysmal dilatation. This is the first case showing the potential efficacy of rituximab for refractory large-vessel involvement associated with GPA.

[A case of hemangioma at the left renal papilla of the calix with anemia and gross hematuria].

An 18-year-old man was admitted to our hospital due to gross hematuria and proteinuria after a marathon race. Contrast-enhanced CT showed no remarkable findings. His gross hematuria and proteinuria disappeared with- out treatment. One year later, he was admitted to our hospital due to reburrent gross hematuria and anemia (serum hemoglobin level of 8.0 g/dL). Both contrast-enhanced CT and renal arteriography revealed no remarkable find- ings; however, cystoscopy showed that his hematuria came from the left ureteral orifice. Ureteroscopy revealed hemorrhage from a large hemangioma at the left renal papilla of the calix. He presented with intermittent gross hematuria, proteinuria, and hypocomplimentemia, suggesting the possibility of glomerulonephritis. His gross hematuria and proteinuria improved after laser coagulation was performed.

Calibration and evaluation of routine methods by serum certified reference material for aldosterone measurement in blood.

We attempted to study the standardization of aldosterone measurement in blood. The serum certified reference material (serum CRM) was established by spiking healthy human serum with pure aldosterone. ID-LC/MS/MS as a reference measurement procedure was performed by using the serum CRM. LC-MS/MS as a comparison method (CM) was routinely used for clinical samples, and the values with and without calibration by the serum CRM were compared. The serum CRM demonstrated similar reactivity with peripheral blood plasma as clinical samples in routine methods (RM) of RIA, ELISA, and CLEIA. In comparison between RM and CM, the results in regression analysis indicated that the range of the correlation coefficient (r) was 0.913 - 0.991, the range of y intercept was 0.9 - 67.3 pg/mL and the range of slope was 0.869 - 1.174. The values by RM in 100 - 150 pg/mL for the diagnostic level, had a significant calibration effect, and the relative difference between calibrated value in RM and result by CM was within ±20%. Furthermore, the calibrated value using the serum CRM was 10,187 pg/mL, which corresponds to measured value of 14,000 pg/mL using RIA for the adrenal venous sampling. Measured values between plasma and serum as a sample for the aldosterone measurement from clinical samples showed no significant differences. In conclusion, we succeeded to prepare the certified reference material of aldosterone for RM. Then, we can accurately calculate corrected values by using our equation for four RMs of determination of aldosterone.

[Secondary hypertension].

Hypertension is a common disease and a crucial predisposing factor of cardiovascular diseases. Approximately 10% of hypertensive patients are secondary hypertension, a pathogenetic factor of which can be identified. Secondary hypertension consists of endocrine, renal, and other diseases. Primary aldosteronism, Cushing's syndrome, pheochromocytoma, hyperthyroidism, and hypothyroidism result in endocrine hypertension. Renal parenchymal hypertension and renovascular hypertension result in renal hypertension. Other diseases such as obstructive sleep apnea syndrome are also very prevalent in secondary hypertension. It is very crucial to find and treat secondary hypertension at earlier stages since most secondary hypertension is curable or can be dramatically improved by specific treatment. One should keep in mind that screening of secondary hypertension should be done at least once in a daily clinical practice.