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Acute phosphate nephropathy (APN) is an acute renal failure secondary to the use of oral sodium phosphate (OSP) laxatives, with a high risk of progression to chronicity. We report a 60-year-old woman with mixed connective tissue disease whose serum creatinine increased up to 2.0 mg/dL in her regular control tests, without an evident causative factor. Kidney biopsy showed numerous intratubular calcium phosphate deposits, consistent with APN. She had a history of OSP laxative intake, and a sodium phosphate enema was used before a colonoscopy performed six months earlier. The temporal association between the use of OSP laxatives and acute kidney injury, should lead to the suspicion of APN. The urine sediment is generally normal or with mild to moderate proteinuria. The diagnosis is confirmed with a kidney biopsy. Until now, there is no specific treatment for APN, thus prevention is essential. In high-risk patients for developing APN, the administration of these laxatives should be avoided.

Excessive sodium intake is associated with increased cardiovascular morbidity and mortality. Daily sodium intake is usually inferred from sodium excretion in a 24-hour urine collection, which is cumbersome and prone to errors. Different formulas have attempted to estimate 24-hour urinary sodium from a spot urine sample. Unfortunately, their concordances are insufficient and have not been tested in our population.To develop an equation to predict 24-hour urine sodium from parameters in plasma and spot urine samples. To validate the equation and compare it with other formulas in Chilean population.Analysis of 24-hour urine collections, plasma sample and spot urine sample from 174 adult outpatients (81% females) with an estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73m2. These were collected between 2015 and 2019 using standardized methods and educating patients about the correct method to collect 24 h urine samples. In all these patients, creatinine and electrolytes were measured in plasma and urine. A new equation was developed using a multiple linear regression model.Twenty-four-hour urine sodium excretion was significantly correlated with age, weight, height, eGFR, plasma osmolarity, urine electrolytes and parameters obtained from spot urine sample, among others. The new equation had a linear correlation with 24-hour natriuresis of 0.91 and the concordance was 0.9. The predictive capacity of the new equation was better than the existing formulas.We developed a formula to accurately predict daily natriuresis in the Chilean population.

Spinal muscular atrophy is an uncommon cause of ketoacidosis, where there is a decrease in muscle mass, an abnormal metabolism of glucose and fatty acids, and changes in neuroendocrine function. These conditions favor the accumulation of keto acids and the development of metabolic acidosis. We report a 26-year-old female, with a history of spinal muscular atrophy type III, consulting for abdominal pain and vomiting lasting one week. She was admitted to the emergency service somnolent and poorly perfused. She had a pH of 6.98, HCO3- of 3.8 mmol/L, pCO2 of 16.4 mmHg, BE of -26 mmol/L, delta ratio of 1.05, anion gap of 31 mEq/L, creatinine of 0.37 mg/dL, sodium of 147 mEq/L, potassium of 3.7 mEq/L, chloride of 112 mEq/L, lactate of 1.2 mmol/L, glucose of 108 mg/dL, albumin of 4.2 g/dL, ketonemia +++, ketonuria +, measured plasma osmolality of 322 mOsm/kg, estimated osmolality of 314 mOsm/kg, toxilab negative, salicylate levels3 µg/mL, acetaminophen levels1.2 µg/mL. Intravenous hydration and bicarbonate were started, without satisfactory response. Interpreting the clinical picture as a ketoacidosis induced by stress in a patient with spinal muscular atrophy, it was handled with glucose, amino acids, vitamins and trace elements, with a favorable response.

Hemolytic uremic syndrome (HUS) is a type of thrombotic microangiopathy where organic damage predominates in the kidney. Atypical HUS (aHUS) is a rare disease that affects young adults and causes terminal chronic renal failure ending in dialysis, in most cases. It also recurs after kidney transplantation. aHUS is associated with genetic defects of the alternative complement pathway or its activation by other factors such as drugs, autoimmune diseases, infections, malignant hypertension and ischemia-reperfusion. We report two women aged 17 and 25 years old with catastrophic aHUS. In both cases, complement amplifying factors (drugs and infections) were added and acted on a genetic vulnerability to precipitate complement activation and produce aHUS. Both patients developed terminal renal failure and had to undergo hemodialysis. Fortunately, after a broad etiological study, it was possible to make the diagnosis of aHUS and start treatment with Eculizumab, a monoclonal antibody that changed the natural history of aHUS. It inhibits complement activity controlling microangiopathy and preventing the development of end-stage renal disease. It also improves the success rate in kidney transplantation. In the case of our patients, both discontinued dialysis after chronic treatment with Eculizumab.

Atherosclerotic renal artery stenosis may result in hypertension and ischemic nephropathy. Renal artery endovascular stenting has emerged as current therapy; however, the percentage of patients who benefit from this procedure is still not well established. The authors studied 116 hypertensive patients with atherosclerotic renovascular stenosis who underwent successful renal artery stenting for the first time. At 1 year, there was a significant overall decrease in blood pressure in the group after stenting; however, there was no change in renal function. Also, no significant change in the number of antihypertensive drugs was noted. Blood pressure improved in 55% of the patients, worsened in 14%, and remained unchanged in 31%. Renal function improved in 16% of the patients, worsened in 30%, and remained stable in 54%. In relation to blood pressure control, patients with resistant or difficult‐to‐control hypertension showed the most improvement in blood pressure control after stenting.

The present review examines the types of hypertension that women may suffer throughout life, their physiopathological characteristics and management. In early life, the currently used low-dose oral contraceptives seldom cause hypertension. Pregnancy provokes preeclampsia, its main medical complication, secondary to inadequate transformation of the spiral arteries and the subsequent multisystem endothelial damage caused by deportation of placental factors and microparticles. Hypertension in preeclampsia is an epiphenomenon which needs to be controlled at levels that reduce maternal risk without impairing placental perfusion. The hemodynamic changes of pregnancy may unmask a hypertensive phenotype, may exacerbate a chronic hypertension, or may complicate hypertension secondary to lupus, renovascular lesions, and pheochromocytoma. On the other hand a primary aldosteronism may benefit from the effect of progesterone and present as a postpartum hypertension. A hypertensive pregnancy, especially preeclampsia, represents a risk for cardiac, vascular and renal disease in later life. Menopause may mimic a pheochromocytoma, and is associated to endothelial dysfunction and salt-sensitivity. Among women, non-pharmacological treatment should be forcefully advocated, except for sodium restriction during pregnancy. The blockade of the renin-angiotensin system should be avoided in women at risk of pregnancy; betablockers could be used with precautions during pregnancy; diuretics, ACE inhibitors and angiotensin receptor antagonists should not be used during breast feeding. Collateral effects of antihypertensives, such as hyponatremia, cough and edema are more common in women. Thus, hypertension in women should be managed according to the different life stages.

The typical symptoms of pheochromocytoma are palpitations, sweating, headaches and hypertension. We report a 70-year-old female admitted to the hospital due to a sudden onset of precordial pain with electrocardiographic changes. After admission the patient evolved with recurrent chest pain accompanied by hypertensive paroxysms and a pheochromocytoma was suspected. Measurement of catecholamines and metanephrines confirmed the diagnosis and an abdominal magnetic resonance localized the tumor. The patient underwent surgery with successful removal of the pheochromocytoma and was discharged in good conditions.

Recognizing cardiovascular risk in overweight adults is challenging, as they usually have a low Framingham risk score (FRAM). In these subjects, non-traditional biomarkers could improve risk stratification.To assess carotid intima media thickness (CIMT) and ultrasensitive C-reactive protein (usCRP) among overweight and obese subjects without metabolic syndrome (MetSyn).In 1558 asymptomatic participants (816 women, 45 ± 11 years) we measured body mass index (BMI), waist circumference, blood pressure, lipid profile, blood glucose, FRAM, usCRP and CIMT. For analytical purposes, we divided the subjects in three groups according to BMI and number of ATPIII-MetSyn risk factors (RF): 1) BMI25 and3RF, 2) BMI ≥ 25 and3RF and 3) BMI ≥ 25 and ≥ 3RF.Participants of group 2 (BMI ≥ 25 and3RF) had a low FRAM (8%). Compared with participants of group 1, they had a higher CIMT (0.61 ± 0.1 and 0.57 ± 0.09 mm, respectively, p0.01) and usCRP (2.1 ± 2.1 and 1.5 ± 1.9 mg/L respectively, p0.01).This study shows that although subjects with overweight/obesity without MetSyn have low cardiovascular risk based on FRAM, they have higher CIMT and usCRP than their normal weight counterparts.

Cardiovascular risk factor (RF) assessment is essential to prevent and predict cardiovascular disease. The presence of RF at early ages, are determinant for the presence of atherosclerosis later in life.To determine the RF profile of young subjects with high carotid intima media thickness (CIMT).We studied 689 subjects (50% women, mean age 36±6 years) from Santiago, Chile. We determined body mass index (BMI), waist circumference, blood pressure, fasting serum lipids, blood glucose and C-reactive protein. CIMT was assessed by ultrasound using an automatic border recognition software.Body mass index, waist circumference, blood pressure and serum lipids were significantly higher among subjects located in the higher CIMT quartile. Also, subjects in the higher quartile of CIMT had a higher prevalence of three or more RF compared with the lower quartile (p = 0.01). Finally, individuals with three or more RF showed three times more risk of being in the higher CIMT quartile, than subjects with no RF (odds ratio = 3.1, p0.01).There is a negative influence of cardiovascular RF on CIMT among young subjects.

LDL, HDL cholesterol and triglycerides, are the most commonly used lipid cardiovascular risk predictor indicators. However population based studies have shown that non-HDL cholesterol and total/HDL cholesterol ratio are better predictors, are easy to measure and do not require fasting.To determine which lipid indicators are better determinants of subclinical atherosclerosis, measured by intima media thickness (IMT) among subjects without demonstrated atherosclerosis.Lipid profile, height, weight, blood pressure and bilateral IMT, measured by ultrasound with automatic border recognition software, were assessed in 770 men and 854 women aged 45 ± 11 years, in Santiago de Chile.Mean total cholesterol was 202, HDL 50, LDL 121, triglycerides 157 and non-HDL cholesterol 152 mg/dl. Total/HDL cholesterol ratio was 4.3. Mean IMT was 0.62 mm. All lipid markers were significantly correlated with IMT. This correlation was higher for non-HDL cholesterol (r = 0.24, p0.0001) and total/HDL cholesterol ratio(r = 0.23, p0.0001). In both men and women, total/HDL cholesterol ratio was the best predictor of having an IMT over the 75th percentile (odds ratio 1.21, 95% confidence intervals 1.09-1.35, p0.01).Total/HDL cholesterol ratio was the best determinant of subclinical atherosclerosis.

Carotid intima media thickness (CIMT) is a marker of cardiovascular damage that can be modified by traditional risk factors.To determine attributable risk factors for a high CIMT among healthy adults.A sample of 1270 individuals (636 males and 634 females) aged 44 ± 11 years, was studied. Blood pressure, weight, height, lipid profile and blood glucose were measured in all. CIMT and the presence of atherosclerotic plaques were determined by carotid ultrasound. Standard criteria were used to define hypertension, dyslipidemia and diabetes.Mean CIMT in the sample studied was 0.62 ± 0.01 mm and percentile 75 was 0.67. The most important risk factor for a CIMT over percentile 75 and the presence of atherosclerotic plaques was hypertension with attributable risks of 54 and 57%, respectively.In this sample, the main risk factor for a high CIMT was hypertension.

Hypokalemia (serum K+3.5 mEq/1) is a potentially serious adverse effect of diuretic ingestion. We report a 27 year-old woman admitted with muscle weakness, a serum potassium of 2.0 mEq/1, metabolic alkalosis and EKG abnormalities simulating cardiac ischemia, that reverted with potassium chloride administration. She admitted high dose furosemide self-medication for edema. Glomerular filtration rate, tubular sodium reabsorption, potassium secretion, the renin-aldosterone system, total body water distribution and capillary permeability, were studied sequentially until 90 days after her admission. There was hyperactivity of the renin-aldosterone axis, reduction in extracellular and intracellular volumes, normal capillary permeability and high sodium tubular reabsorption, probably explained by a "rebound" salt retention associated with her decreased extracellular volume.

The treatment of AL amyloidosis was not successful until the advent of myeloablative chemotherapy consisting of high-dose intravenous melphalan followed by autologous peripheral blood stem cell transplantation. This new treatment has achieved better survival rates and, remarkably, it has obtained complete remission. Among patients with renal involvement, achievement of a complete hematological response was associated with a 50% reduction in proteinuria and stable creatinine clearance in more than 2/3 of patients. Despite of these excellent results, this new therapy is associated with significant toxicity, including the development of acute renal failure due to white blood cell lysis syndrome. We report a 59 year-old female with a nephrotic syndrome due to primary amyloidosis successfully treated autologous stem cell transplantation who developed acute renal failure caused by white blood cell lysis syndrome. The patient required treatment with granulocytic colony stimulating factor and intermittent hemofiltration and was discharged 23 days after melphalan administration with a satisfactory renal function and white blood cell count. After one year of follow up, she maintains a good glomerular filtration rate, a proteinuria of less than, 1 g/day and normal hematological values.

Pheochromocytoma, though an uncommon cause of hypertension, can be a lethal condition. Because of this it is mandatory to diagnose it or rule it out in presence of suggestive symptoms. Typical symptoms are palpitations, sweating, severe headaches and hypertension. However, there are other suggestive symptoms of this dangerous endocrine entity, one of which is the orthostatic hypotension. We report the case of a 65 years old female patient with long standing hypertension in whom the pheochromocytoma was suspected after episodes of orthostatic hypotension. Although this manifestation was described almost fifty years ago, its frequency and pathophysiology has not yet been well established and fully elucidated. Moreover, it has meaningful implications in relation to preoperatory management and the timing of surgery.

This review provides current understanding of the pathophysiology of pheochromocytoma and the wide range of associated clinical manifestations that have led to earlier recognition of the disease. In addition, it reviews optimal screening methods and localization techniques that have enhanced the clinician’s ability to make the diagnosis with greater certainty. This article will also discuss alternative antihypertensive regimens and innovative anesthetic and surgical procedures that have made successful management more promising than ever before.Areas requiring further development include additional clinical experience with the measurement of plasma metanephrines that have been shown to have high sensitivity and specificity in the diagnosis of sporadic and familial pheochromocytoma, optimizing cost effectiveness of diagnostic imaging, improving the ability to predict and treat malignant pheochromocytoma, and elucidating not only the surgical approach but, perhaps with rapid advances in molecular genetics, ways of preventing familial pheochromocytoma.

Microalbuminuria strongly predicts cardiovascular morbidity and mortality, clinical nephropathy, and progression of renal disease in high-risk populations. We recommend screening patients with type 2 diabetes, older patients with type 1 diabetes, and older patients with stage 2 hypertension or higher (ie, > 160/100 mm Hg). KEY POINTS Microalbuminuria is defined as albumin excretion of 20 to 200 μg/minute (30-300 mg/24 hours) in a 24-hour sample, or an albumin-to-creatinine ratio greater than 30 mg/g in a first morning midstream sample. In type 2 diabetes, microalbuminuria is strongly associated with traditional cardiovascular risk factors and is a harbinger of later cardiovascular complications. In type 1 diabetes, microalbuminuria might be an independent predictor of cardiovascular complications, particularly in patients older than 45 years. In people older than 45 years with stage 2 or higher hypertension, microalbuminuria seems to be strongly associated with several traditional and nontraditional cardiovascular risk factors and with target-organ damage. Whether microalbuminuria is a good predictor of cardiovascular disease in people with well-controlled essential hypertension remains to be determined.