Suplementación efectiva de vitamina D en pacientes con fractura tibial / Effective vitamin D supplementation in patients with tibial fracture

OBJETIVOS Determinar la prevalencia de déficit de vitamina D, así como evaluar la seguridad y efectividad de un nuevo método de carga con colecalciferol en pacientes adultos con fractura de tibia. MATERIALES Y MÉTODOS Se reclutaron a 56 pacientes consecutivos con edades entre 18 y 65 años con fractura de tibia ingresados en nuestro hospital durante 1 año. Se determinó el nivel de 25-hidroxivitamina D ([25(OH)-D]) al ingreso y tras suplementación con 100.000 UI semanales de colecalciferol, durante 3 o 5 semanas, en casos de insuficiencia ([25(OH)-D] entre 20 ng/mL y 29,9 ng/mL) o deficiencia ([25(OH)-D] < 20 ng/mL), respectivamente. Se determinó la prevalencia de hipovitaminosis D, el porcentaje de normalización de [25(OH)-D], y los efectos adversos. RESULTADOS Se evaluaron 56 pacientes; 98,2% presentó hipovitaminosis D, y 28 (73,7%) y 10 (26,3%) presentaron déficit e insuficiencia, respectivamente. Tras la suplementación, 92,1% alcanzaron niveles [25(OH)-D] normales. Ningún paciente presentó efectos adversos. DISCUSIÓN La prevalencia de deficiencia de vitamina D en nuestra población fue mayor a la reportada en la literatura. Comprobamos que un esquema de suplementación en altas dosis de vitamina D es seguro, y más efectivo que los previamente recomendados. Este esquema de suplementación puede ser implementado en futuros estudios randomizados. CONCLUSIÓN La prevalencia de hipovitaminosis D en pacientes adultos chilenos con fractura de tibia fue alta (98,2%). El esquema de suplementación con vitamina D propuesto fue efectivo y seguro.

OBJETIVOS Determinar la prevalencia de déficit de vitamina D, así como evaluar la seguridad y efectividad de un nuevo método de carga con colecalciferol en pacientes adultos con fractura de tibia. MATERIALES Y MÉTODOS Se reclutaron a 56 pacientes consecutivos con edades entre 18 y 65 años con fractura de tibia ingresados en nuestro hospital durante 1 año. Se determinó el nivel de 25-hidroxivitamina D ([25(OH)-D]) al ingreso y tras suplementación con 100.000 UI semanales de colecalciferol, durante 3 o 5 semanas, en casos de insuficiencia ([25(OH)-D] entre 20 ng/mL y 29,9 ng/mL) o deficiencia ([25(OH)-D] < 20 ng/mL), respectivamente. Se determinó la prevalencia de hipovitaminosis D, el porcentaje de normalización de [25(OH)-D], y los efectos adversos. RESULTADOS Se evaluaron 56 pacientes; 98,2% presentó hipovitaminosis D, y 28 (73,7%) y 10 (26,3%) presentaron déficit e insuficiencia, respectivamente. Tras la suplementación, 92,1% alcanzaron niveles [25(OH)-D] normales. Ningún paciente presentó efectos adversos. DISCUSIÓN La prevalencia de deficiencia de vitamina D en nuestra población fue mayor a la reportada en la literatura. Comprobamos que un esquema de suplementación en altas dosis de vitamina D es seguro, y más efectivo que los previamente recomendados. Este esquema de suplementación puede ser implementado en futuros estudios randomizados. CONCLUSIÓN La prevalencia de hipovitaminosis D en pacientes adultos chilenos con fractura de tibia fue alta (98,2%). El esquema de suplementación con vitamina D propuesto fue efectivo y seguro.

Enfermedad relacionada a IgG4. Serie clínica de pacientes chilenos / IGG4-related disease. Report of 52 patients

BACKGROUND: IgG4-related disease (IgG4 RD) is an immune-mediated fibro-inflammatory disorder, with tissue infiltration of IgG4+ plasma cells. It causes pseudotumors, tumors, and a wide spectrum of clinical manifestations. AIM: To report the clinical, laboratory, histopathological and treatment characteristics of a group of Chilean patients with IgG4 RD. MATERIAL AND METHODS: Review of medical records of 52 patients aged 18 to 76 years with IgG4 RD seen at six medical centers. RESULTS: Elevated IgG4 serum levels (> 135 mg/dl) were found in 18 of 44 (41%) patients. There was histological confirmation of the disease in 46 patients. The most common sites of involvement were lungs, eyes and kidneys. Eighteen (35%) patients had only one organ involved, 34 (65%) patients had two organs and 13 (25%) patients had three or more organs. The involvement of two organs was significantly more common in men (p < 0.05). In patients with only one organ involvement, the most frequent location was orbital and meningeal. All patients with kidney or lung disease had multiorgan involvement. All patients received corticosteroid therapy, 67% synthetic immunosuppressants, and 16% rituximab. CONCLUSIONS: ER-IgG4 can affect any tissue. Multiorgan involvement was more common in this series, with preference for lungs, eyes and kidneys. An excellent response to steroids is characteristic of the disease, but with a high relapse rate that requires additional immunosuppression.

Nueva ecuación para la estimación de la natriuresis diaria a partir de parámetros en plasma y orina aislada en población chilena / A new equation to estimate daily natriuresis from parameters in plasma and spot urine sample in the Chilean population

Background: 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. Aim: 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. Material and Methods: 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. Results: 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. Conclusions: We developed a formula to accurately predict daily natriuresis in the Chilean population.

Análisis de sobrevida en pacientes incidentes de hemodiálisis en Chile, 2013-2019

Background: Renal replacement therapies, especially hemodialysis (HD) in end-stage kidney disease, avoid an inevitable death caused by the disease. However, in elderly patients with multiple comorbidities, this therapy could derive in a comparable survival than conservative management. Considering that HD represents a high cost for the health system, it is worth analyzing the effects of HD on survival. Aim: To analyze the survival and mortality of all national health security system's patients (FONASA) admitted to HD in Chile from 2013 to 2019. Material and Methods: We requested to the Ministry of Health information about all patients affiliated to the public health insurance system that started dialysis between 2013 and 2019. We evaluated the influence of age when starting HD, sex, presence of hypertension, presence of diabetes mellitus (DM), the region of residence, and year of admission on mortality. Results: A total of 24,113 patients aged 61 ± 15 years (45% women) were analyzed. Forty five percent of patients were aged > 65 years. After 5 years of follow-up, the median survival in this age group was 36.1 months. Among patients who started HD at age > 85 years, the median survival was 14.8 months. Diabetic patients had a median survival of 52.3 months. Advanced age and DM were associated with higher annual mortality. Also, the region of residence and year of admission were associated with higher mortality at 3 and 12 months. Conclusions: The median survival of patients on HD is dependent on age and the presence of comorbidities, among other factors. We performed an analysis to determine if starting HD in older patients with comorbidities has a real benefit over conservative management in terms of survival.

Metahemoglobinemia, una entidad de diagnóstico complejo. Reporte de un caso

Methemoglobinemia is a rare condition with serious consequences if not diagnosed. We report the case of a 64-year-old woman with a history of allergy to sulfa drugs and a recent diagnosis of a small vessel vasculitis (ANCA-p) who started induction therapy with corticosteroids and rituximab. Due to the need for infectious prophylaxis, and considering her history, dapsone was administered instead of cotrimoxazole after ruling out glucose-6-phosphate dehydrogenase deficiency. During the admission to the hospital for her second dose of rituximab, and while being asymptomatic, she persistently presented a pulse oximetry ≪ 90% despite the administration of O2. Therefore, the infusion was postponed to study the patient. The arterial gasometric study by direct potentiometry revealed an O2 saturation of 98%, with a saturation gap > 5%. Considering the use of dapsone, a methemoglobinemia was suspected and confirmed by co-oximetry (methemoglobinemia 9%). Dapsone was suspended and one week later, her methemoglobinemia was absent.

Hipercalcemia severa en el curso de rabdomiolisis: caso clínico / Rhabdomyolysis and severe hypercalcemia: report of one case

Rhabdomyolysis (RD) is the process that leads to cell destruction of striated muscle. Causes include inherited metabolic defects or acquired disorders. RD is frequently associated with acute kidney injury (AKI) and disorders of calcium metabolism. We report a 33 year old man that after amphetamine consumption and an uninterrupted 3,000 km driving presented vomiting, muscle pain and dark urine. He had elevated creatinkinase levels, severe hypocalcemia and an acute renal failure. He was treated with hemodialysis and calcitriol. He was transferred to our hospital and on admission a serum calcium of 18 mg/dl was detected. He continued on hemodialysis, recovering renal function and with normalization of creatinkinase levels and serum calcium level.

Intoxicación por ácido acetilsalicílico, fisiopatología y manejo / Physiopathology and management of acetylsalicylic acid intoxication

Acetylsalicylic acid (ASA) intoxication is potentially lethal. After ingestion, AAS is rapidly transformed into salicylic acid that dissociates into an hydrogen ion plus salicylate. Salicylate is the main form of AAS in the body and produces multiple alterations. Initially, the stimulation of the ventilatory center promotes a respiratory alkalosis. Then, the mitochondrial dysfunction induced by salicylate, will generate a progressive metabolic acidosis due to the accumulation of ketoacids, lactic acid and dicarboxylic acids among others. Another alterations include hydro electrolytic disorders, gastrointestinal lesions, neurological involvement, ototoxicity and coagulopathy. The correct handling of acetylsalicylic acid intoxication requires an thorough knowledge of its pharmacokinetics and pharmacodynamics. Treatment consists in life support measures, gastric lavage, activated charcoal and urinary alkalization to promote the excretion of salicylates. In some occasions, it will be necessary to start renal replacement therapy as soon as possible.

Síndrome hemolítico urémico atípico / Atypical hemolytic uremic syndrome

Atypical hemolytic uremic syndrome (aHUS) is a rare thrombotic microangiopathy, characterized by microangiopathic hemolytic anemia, thrombocytopenia and renal involvement. It causes end stage renal disease requiring dialysis in most affected patients. It mainly affects young adults (contrary to what was thought years ago). When aHUS is primary, the cause is a genetic mutation in the alternative complement pathway. Instead, secondary aHUS is caused by external factors that trigger the disease by themselves or in combination with a genetic vulnerability. The type of mutation determines the severity of the disease, prognosis, response to therapy and renal transplantation. Advances in the understanding of renal diseases associated with complement defects and the development of specific biologic therapies changed the course of this disease. Eculizumab is internationally approved for the treatment of primary aHUS. Its inhibitory action on the complement cascade leads to hematologic remission and restoration of renal function. We present a review of aHUS detailing its etiology, pathogenesis, clinical presentation, diagnosis and treatment.

Caracterización del metabolismo óseo mineral en pacientes con enfermedad renal crónica en hemodiálisis en el Servicio de Salud Metropolitano Sur, Santiago de Chile / Bone mineral metabolism in patients with chronic kidney disease on dialysis in Southern Metropolitan Santiago

Background: Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD) is a condition of dialysis patients associated with both morbidity and mortality. Management is based on clinical guidelines with goals that are hard to comply with. Aim: To describe and compare biochemical variables associated with this disorder in two different time periods. Material and Methods: Revision of medical records of 814 patients (49% females) dialyzed during 2009 and 1018 patients (48% females), dialyzed during 2012 in Southern Metropolitan Santiago. Information about serum calcium, phosphorus, parathyroid hormone (PTH) and albumin was retrieved. Results: Median PTH values in 2009 and 2012 were 222.5 and 353.5 pg/ml respectively (p < 0.05). The figures for serum calcium corrected by albumin were 9.0 and 8.5 mg/dl respectively (p < 0.05). The figures for phosphorus were 4.7 and 5.0 mg/dl respectively (p < 0.05). The Calcium x Phosphorus product was 41.4 and 42.5 mg²/dl² (p < 0.05). Of note, the proportion patients with serum calcium below recommended levels (< 8.4 mg/dl) increased from 16% to 40% from 2009 to 2012. The proportion of patients with biochemical variables within recommended ranges was lower in 2012 than in 2009. Conclusions: There was a low proportion of patients with bone metabolism parameters within ranges recommended by clinical guidelines. These parameters were worst in 2012.

Daño vascular en la enfermedad renal crónica: [revisión] / Vascular damage in chronic kidney disease: [review]

Cardiovascular disease is a frequent complication of renal failure and is the most common cause of death in patients with chronic kidney disease (CKD). Accelerated atherogenesis has been widely documented in CKD and diabetic nephropathy is the leading cause of renal failure worldwide. Furthermore, CKD promotes hypertension and dyslipidemia, which in turn may contribute to the progression of renal failure. All together, hypertension, dyslipidemia and diabetes are considered major risk factors for the development of endothelial dysfunction and progression of atherosclerosis. Elevated inflammatory mediators and activation of the renin-angiotensin system contribute through enhanced production of reactive oxygen species, to atherogenesis in CKD. Vascular calcification is also important. Calcification of arteries occurs in the intima in association with atherosclerosis, where it may contribute to plaque formation, and in the media, where it causes stiffening. Increased serum levels of calcification promoters, such as hyperphosphatemia, and a decrease in circulating and local inhibitors of calcification, favor vascular calcification. On the other hand, transdifferentiation of vascular smooth muscle cells to osteblast-like cells would be the pivotal event in calcification. Bone morphogenetic protein agonists and antagonists are playing a role in this osteogenic differentiation. Accelerated atherosclerosis and media calcification will then lead to increased prevalence of coronary artery disease, heart failure, stroke, and peripheral arterial disease. Prevention and treatment of cardiovascular disease are major considerations in the management of individuals with CKD.

Hipokalemia, hipovolemia y repercusión electrocardiográfica secundarias a ingesta prolongada de furosemida: Caso clínico / Hypokalemia, hypovolemia and electrocardiographic changes due to furosemide abuse: Report of one case

Hypokalemia (serum K+ < 3.5 mEq/1) is a potentially serious adverse effect of diuretic ingestión. 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 reabsortion, 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.