Pablo Young

Creatinine- vs. cystatin C-based equations compared with 99mTcDTPA scintigraphy to assess glomerular filtration rate in chronic kidney disease.

BACKGROUND In chronic kidney disease (CKD), accurate estimation of the glomerular filtration rate (GFR) is mandatory. Gold standard methods for its estimation are expensive and time-consuming. We compared creatinine- versus cystatin C-based equations to measure GFR, employing (99m)Tc-DTPA scintigraphy as the gold standard. METHODS This was a prospective cross-sectional observational study including 300 subjects. CKD was defined according to K/DOQI guidelines, and patients were separated into groups: stage 1 (G1), n=26; stage 2 (G2), n=52; stage 3 (G3), n=90; stage 4 (G4), n=37; stage 5 (G5), n=60; and control group, n=35. Creatinine-based estimates were from 24-hour creatinine clearance using the Walser formula, Cockcroft-Gault, MDRD-4 and CKD-EPI; cystatin C equations used were Larsson, Larsson modified equation, Grubb and Hoek. RESULTS Age and body mass index were different among groups; proteinuria, hypertension, diabetes and primary glomerulopathies significantly increased as CKD worsened. In the global assessment, CKD-EPI and Hoek gave the highest correlations with (99m)Tc-DTPA: rho=0.826, p<0.001 and rho=0.704, p<0.001, respectively. Most significant linear regressions obtained: CKD-EPI vs. (99m)Tc-DTPA, Hoek vs. (99m)Tc-DTPA and CKD-EPI vs. Hoek. However, important differences emerged when each group was analyzed separately. Best significant correlations obtained with (99m)Tc-DTPA: control group, creatinine clearance rho=0.421, p=0.012; G1, Crockoft-Gault rho=0.588, p=0.003; G2, CKD-EPI rho=0.462, p<0.05; G3, CKD-EPI rho=0.508, p<0.001; G4, Hoek rho=0.618, p<0.001; G5, CKD-EPI rho=0.604, p<0.001. CONCLUSIONS At GFR <60 ml/min, CKD-EPI and Hoek equations appeared to best correlate with (99m)TcDTPA. In controls and at early stages of CKD, creatinine-based equations correlated better with (99m)Tc-DTPA, with CKD-EPI being the one with the best degree of agreement.

Proteinuria: an ignored marker of inflammation and cardiovascular disease in chronic hemodialysis.

Background Cardiovascular disease is the leading cause of morbidity and mortality in hemodialysis (HD) patients, the main etiologies being diabetes and hypertension. Cardiac and inflammatory biomarkers are usually employed to assess risk or damage, or during follow-up. Proteinuria is considered a strong predictor of morbidity, a cause of inflammation, oxidative stress, hemodynamic alteration, and progression of chronic kidney disease. However, proteinuria is rarely considered in the clinical assessment of HD patients. Methods This was a concurrent, cohort-observational, cross-sectional study in which 52 chronic HD subjects were divided into three groups according to the degree of proteinuria: Group (G) A: <1 g/day, n = 25; GB: 1–3 g/day, n = 13; GC: >3 g/day, n = 14. Baseline hemoglobin, albuminemia, cholesterol, body mass index, Malnutrition-Inflammatory Score, pro-B-type natriuretic peptide, troponin T, C-reactive protein (CRP), and ultrafiltration rates were analyzed. Results There was no difference between groups in terms of baseline age, gender, hypertension, cause of renal failure, hemoglobin, cholesterol, albumin, CRP levels, cardiac biomarkers, adiponectin, body mass index, or Malnutrition-Inflammatory Score. Time on HD: GA, 34.56 ± 23.3 (range [r]: 6–88); GB, 25.15 ± 19.40 (r: 6–58); GC, 18.21 ± 9.58 (r: 6–74) months; P = 0.048. Proteinuria: GA, 0.33 ± 0.30 (r: 0.0–0.88); GB, 1.66 ± 0.54 (r: 1.03–2.75); GC, 7.18 ± 2.80 (r: 3.04–21.5) g/day; P < 0.001. Mean ultrafiltration rates were significantly different: GA, 2.80 ± 0.73; GB: 1.85 ± 0.96 liters/session; P = 0.003. Fourteen diabetic patients were identified (27%): GA, 3 (12%); GB, 3 (23%); GC, 8 (57%); P = 0.009. A positive and significant correlation was observed between diabetes and proteinuria >3 g/day: rho 0.438, P = 0.027. Although troponin T, pro-B-type natriuretic peptide, adiponectin, and CRP were not different among groups, the positive correlation between troponin T and CRP elevated significantly as proteinuria increased: GA, rho 377, P = 0.063; GB, rho 663, P = 0.013; GC, rho 687, P = 0.007. Conclusion In chronic HD, nephrotic-range proteinuria was significantly higher in diabetic nephropathy patients versus other causes. This was associated with inflammation and cardiac stress and was independent of fluid removal. Proteinuria >3 g/day was associated with shorter time on HD. Whether severe proteinuria is associated with shorter survival in HD, independent of diabetes, is to be determined. Proteinuria should be considered in the assessment of cardiovascular and inflammatory states in HD patients.

Elevated pro-brain natriuretic peptide, troponin T and malnutrition inflammatory score in chronic hemodialysis patients with overt cardiovascular disease.

Background: We assessed the relationship between pro-brain natriuretic peptide (pro-BNP), troponin T (TropT) and nutritional status. Methods: A total of 48 chronic hemodialysis patients were grouped according to the presence [group A (GA); n = 24] or not [group B (GB)] of cardiovascular disease. Results: Compared to GB subjects, GA subjects were older, had been on hemodialysis for a longer period and had higher prevalences of vascular grafts, hypertension and elevated C-reactive protein (CRP) [GA vs. GB: 1.1 (range 0.1–32.9) vs. 0.4 (0–28.1) mg/dl; p = 0.028], malnutrition inflammatory score (MIS) (GA vs. GB: 7.50 vs. 4.00; p = 0.001), pro-BNP [GA vs. GB: 6,760 (601–103,200) vs. 686 (75–83,700) pg/ml; p < 0.001] and TropT [GA vs. GB: 0.3650 (0.011–0.199) vs. 0.010 (0.0–0.290) ng/ml; p = 0.002]. Pro-BNP correlated with TropT (rho 0.539; p < 0.001), MIS (rho 0.502; p < 0.0001), homocysteine (rho 0.321; p = 0.13) and CRP (rho 0.511; p < 0.0001). Pro-BNP levels were lower in GB patients as the body mass index increased; the opposite occurred in GA. Conclusions: Patients with cardiovascular disease had elevated pro-BNP and TropT levels. In patients without cardiovascular disease, malnutrition and inflammation were associated with vascular prostheses, while pro-BNP was lower in obese patients.

In hemodialysis, adiponectin, and pro-brain natriuretic peptide levels may be subjected to variations in body mass index

Adiponectin exerts cardiovascular protective actions, although some studies have shown the opposite. In hemodialysis, obese subjects display lower mortality rates despite hypoadiponectinemia, while higher adiponectin concentrations correlate with an elevated cardiovascular risk in nonobese subjects. The aim of the study is to suggest that adiponectin level variations are associated with differences in the body mass index (BMI). The interplay between adiponectin and pro‐brain natriuretic peptide (Pro‐BNP) levels may vary according to body fat mass. Fifty‐two chronic hemodialysis patients were divided into three groups. Group A, BMI<25 (n=20); Group B, BMI 25 to 30 (n=21), and Group C, BMI>30 (n=11). Diabetics: Group A 10%; Group B 6 29%; Group C 55%, P=0.027. Determinations: Adiponectin, Pro‐BNP, insulin, insulin resistance (HOMA), troponin T, nutritional status, ultrafiltration rates, C‐reactive protein (CRP), vascular accesses, and echocardiography. Group A: adiponectinemia positively and significantly correlated with Pro‐BNP, CRP, and troponin T. As BMI increased, adiponectin, Pro‐BNP, and malnutrition significantly decreased, while insulin, HOMA, and ultrafiltration rates significantly increased. Cardiac restriction was significantly higher in obese patients. In all groups, Pro‐BNP and troponin T displayed a strong positive correlation. In low‐BMI subjects, high Pro‐BNP and adiponectin, low myocardial restriction, and worse nutritional status were prevalent. In obesity, hypoadiponectinemia stimulates cardiac remodeling, cardiac hypertrophy, and decreased stretching, rendering Pro‐BNP levels low despite high ultrafiltration rates. Thus, adiponectin correlates inversely with BMI, probably playing different cardiovascular roles as BMI changes.

William Osler: el hombre y sus descripciones

Background: William Osler was generally regarded as the greatest and most respected physician of his time. This paper describes Oslers life, his philosophy and views. He was an outstanding clinician who emphasized bedside teaching and observation. He possessed an extraordinary charm that inspired many others. As Professor of Medicine at four institutions in three countries, he was a great influence on medical education. He was a prolific writer, and his textbook became the most popular and widely read treatise on medicine in the world. He also was a medical historian, a classical scholar, and an avid bibliophile. He emphasized the value of hard work and ongoing education. His compassion and concern for patients and colleagues reflected his personality. We summarize Oslers descriptions, and some of his aphorisms. His wisdom is as relevant now, as it was in his time. Osler blended the art and science of Medicine perhaps better than anyone else, and remains a valuable role model for students and physicians more than ninety two years after his death. (Rev Med Chile 2012; 140:1218-1227).

Esófago negro secundario a esofagitis necrotizante aguda: reporte de un caso clínico

Acute esophageal necrosis, which presents as a black esophagus on endoscope, is an uncommon occurrence. It is defined as a dark pigmentation of the esophagus associated with histological mucosal necrosis. We report a 75-year-old man who developed black esophagus due to acute esophageal necrosis caused by septicemia. The patient had a favorable evolution.

Estenosis subglótica y granulomatosis con poliangeítis (Wegener) en dos casos: Report of two cases

Granulomatosis with polyangiitis (GPA) or Wegener’s disease is characterized by a granulomatous vasculitis of the upper and lower airways and kidney. It involves the lower respiratory tract causing subglottic tracheal stenosis, which occurs in approximately 22% of patients. We report two females aged 40 and 52 years, admitted to the hospital with a subglottic tracheal stenosis. Their symptoms and management are reviewed. The first patient responded to rituximab. The second patient required a tracheostomy.Granulomatosis with polyangiitis (GPA) or Wegeners disease is characterized by a granulomatous vasculitis of the upper and lower airways and kidney. It involves the lower respiratory tract causing subglottic tracheal stenosis, which occurs in approximately 22% of patients. We report two females aged 40 and 52 years, admitted to the hospital with a subglottic tracheal stenosis. Their symptoms and management are reviewed. The first patient responded to rituximab. The second patient required a tracheostomy.

Subglottic tracheal stenosis in Wegener disease. Report of two cases

Granulomatosis with polyangiitis (GPA) or Wegener’s disease is characterized by a granulomatous vasculitis of the upper and lower airways and kidney. It involves the lower respiratory tract causing subglottic tracheal stenosis, which occurs in approximately 22% of patients. We report two females aged 40 and 52 years, admitted to the hospital with a subglottic tracheal stenosis. Their symptoms and management are reviewed. The first patient responded to rituximab. The second patient required a tracheostomy.Granulomatosis with polyangiitis (GPA) or Wegeners disease is characterized by a granulomatous vasculitis of the upper and lower airways and kidney. It involves the lower respiratory tract causing subglottic tracheal stenosis, which occurs in approximately 22% of patients. We report two females aged 40 and 52 years, admitted to the hospital with a subglottic tracheal stenosis. Their symptoms and management are reviewed. The first patient responded to rituximab. The second patient required a tracheostomy.

Encefalopatía asociada a Valproato

Valproate can be associated to hyperammonemic encephalopathy, characterized by fluctuating sudden-onset alterations of sensorium, focal symptoms and an increase in the frequency of seizures. We report a 78 year-old female using valproate 1,000 mg/ day for 10 months for the treatment to tonic-clonic seizures. She was admitted on three occasions in the last fourth months for self limited clouding of sensorium. Laboratory, imaging and electroencephalografic studies were non-contributory Blood ammonia levels were 123 fig/dl (normal: 15-50 fig/dl). Due to the possibility of a hyperammonemic encephalopathy secondary to valproate, the drug was discontinued and she was treated with lactulose and intravenous L-carnitine, 1 g/day The patient showed a complete recovery within 48 hours. This drug-associated encephalopathy is a reversible but potentially fatal cause, probably underdiagnosed, that requires a high index of suspicion

Linfoma intravascular, un desafio diagnóstico: Caso clínico

Intravascular lymphoma is a rare subtype of extranodal diffuse large B-cell lymphoma characterized by clonal proliferation of lymphocytes inside of small and medium caliber vessels. Its incidence is estimated at one case per million. The clinical picture is very variable, but frequently has skin and central nervous system involvement. It is diagnosed by demonstrating pathological blood vessel infiltration by lymphoma cells. We report a 44 years old male presenting with fever, malaise and erythematous lesions in the abdominal wall. An abdominal wall biopsy showed dilated vascular vessels with atypical cells in their lumen, compatible with large B-cell intravascular lymphoma. He was treated with rituximab, cyclophosphamide, adriamycin, vincristine and prednisone and an autologous hematopoietic stem cell transplantation, achieving a complete remission that has lasted two years.