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991.
Timely referral to nephrologists depends on identification of renal failure. Most primary care physicians and specialists rely on serum creatinine as the standard test for determination of renal function. Creatinine clearance requires 24 hours urine collection with many pitfalls and wrong results. We compare serum creatinine and the Cockcroft-Gault (C-G) equation as measure of glomerular filtration rate (GFR). The study included 1,053 outpatients with serum creatinine lower than 2.5 mg/dl referred to our nephrological laboratory for serum creatinine and GFR determination using the C-G formula. Patients were grouped into two groups: normal renal function (serum creatinine < 1.3 mg/dl) and "incipient" abnormal renal function (serum creatinine 1.3-2.5 mg/dl). In the group of females with normal creatinine 22% (60-70 y), 35% (70-80 y) and 57% (> 80 y) had GFR values below 50 ml/min. In the group of males 11.3% (70-80 y) and 33.3% (> 80 y) also had GFR reduction in spite of normal serum creatinine. A severe renal insufficiency with creatinine clearance lower than 30 ml/min was observed in the group with "incipient" renal failure based on serum creatinine: 22.7%, 40% and 82.9% for females and 6%, 22.7% and 57% for male (60-70 y; 70-80 y; and > 80 y respectively). In order to improve management and prevention of renal failure appropriate measurements of renal function other than serum creatinine should be emphasize.  相似文献   
992.
Necrotizing granulomatous vasculitis in advanced HIV infection   总被引:1,自引:0,他引:1  
We describe the first case of granulomatous necrotizing vasculitis not restricted to the central nervous system in an HIV-infected patient. No mycobacteria or drugs potentially associated with granuloma formation were involved in this patient, suggesting that the cause of this vasculitis was probably autoimmune. The development of granulomatous vascular inflammation in this patient with less than 200 CD4 cells/microl might have been due to immune overactivation. After starting potent antiretroviral therapy a profound immune deactivation was observed and the vasculitis did not relapse.  相似文献   
993.
Several preparations of testosterone and its esters are being investigated alone or in combination with other gonadotropin-suppressing agents as possible antifertility agents for men. We studied the effectiveness of 7 alpha-methyl-19-nortestosterone (MENT) as an antispermatogenic agent in men. MENT has been shown to be more potent than testosterone and to be resistant to 5 alpha-reduction. For sustained delivery of MENT, we used a system consisting of ethylene vinyl acetate implants containing MENT acetate (Ac), administered subdermally. Thirty-five normal volunteers were recruited in 3 clinics and were randomly assigned to 1 of 3 doses: 1 (12 men), 2 (11 men), or 4 (12 men) MENT Ac implants. The initial average in vitro release rate of MENT Ac from each implant was approximately 400 micro g/day. Implants were inserted subdermally in the medial aspect of the upper arm under local anesthesia. The duration of treatment was initially designed to be 6 months. However, in 2 clinics the duration of treatment was extended to 9 months for the 2-implant group and to 12 months for the 4-implant group. Dose-related increases in serum MENT levels and decreases in testosterone, LH, and FSH levels were observed. Effects on sperm counts were also dose related. None of the subjects in the 1-implant group exhibited oligozoospermia (sperm count, <3 million/ml). Four subjects in the 2-implant group became oligozoospermic, 2 of whom reached azoospermia. Eight subjects in the 4-implant group reached azoospermia, with 1 exhibiting oligozoospermia, whereas 2 were nonresponders. Side effects generally seen with androgen administration, such as increases in erythrocyte count, hematocrit, and hemoglobin and a decrease in SHBG, were also seen in this study and were reversible. Changes in lipid parameters were moderate and transient. Liver enzymes showed small changes. This study demonstrates that MENT Ac, when administered in a sustained release fashion via subdermal implants, can inhibit spermatogenesis over a prolonged period after a single administration and has the potential to be used as a male contraceptive.  相似文献   
994.
INTRODUCTION: The causes of cardiac tamponade vary and it has been suggested that underlying causes should be sought in all cases. The purpose of this study was to determine the causes of cardiac tamponade in our environment, distinguishing between specific and idiopathic causes, and analyzing the proportion and causes in the subgroup of patients with relapsing tamponade. PATIENTS AND METHOD: We retrospectively studied all patients who underwent therapeutic pericardiocentesis between 1985 and 2001. The clinical and radiographic features and macroscopic characteristics of the pericardial fluid were analyzed. The final diagnosis in each patient was based on the clinical history, follow-up, pericardial fluid cytology, and pericardial biopsy, if available. RESULTS: Ninety-six patients were included (52 men/44 women), mean age 56.1 16.1 years. The cause of pericardial effusion was neoplasm in 50 patients (52.1%), 14 idiopathic pericarditis (14.6%), 12 renal failure (12.5%), 7 iatrogenic cases (7.3%), 4 mechanical tamponades (4.2%), 2 tuberculosis (2.1%), and 7 other causes (7.3%). Thirty-five patients had relapsing tamponade; only 2 of them had idiopathic pericarditis (5.7%). We found no significant differences in age, development time, extracted volume or fluid features between tamponade of specific or idiopathic origin. CONCLUSIONS: Most of the cardiac tamponades in our series had a specific cause. This made it necessary to identify a specific underlying cause in each case, especially in relapsing effusions. However, we did not find any variable suggestive of the cause of the disease.  相似文献   
995.
The goal of this study was to identify airway and alveolar site(s) of inflammation using exhaled nitric oxide (NO) as a marker in treated patients with asthma, including response to oral corticosteroids, and correlate these sites with expiratory airflow limitation. In 53 (24 male) patients with asthma, age 43 +/- 23 years (mean +/- SD) and all on inhaled corticosteroids, post 180 microg aerosolized albuterol, FEV(1) was 74 +/- 23% predicted and FEV(1)/FVC was 68 +/- 11%. Exhaled NO at 100 ml/second was 27 +/- 23 ppb (p < 0.001 compared with normal, 12 +/- 15 ppb). Bronchial NO maximal flux was 2.4 +/- 3.1 nl/second (p < 0.001 compared with normal, 0.85 +/- 0.55). Alveolar NO concentration was 7.0 +/- 7.4 ppb (p = 0.01 compared with the normal value, 3.2 +/- 2.0 ppb). There was no significant correlation between FEV(1) % predicted or lung elastic recoil and NO bronchial flux or alveolar concentration. However, there was a weak but significant correlation between NO bronchial flux and alveolar concentration (Spearman r = 0.50, p < 0.001). In 10 subjects with asthma on inhaled corticosteroids, 5 days of 30 mg prednisone resulted in isolated significant decreases in NO alveolar concentration, from 13 +/- 10 to 4 +/- 4 ppb (p = 0.002). Despite treatment, including inhaled corticosteroids, patients with asthma may have ongoing separate airway and alveolar sites of NO inflammation, the latter responsive to oral corticosteroids.  相似文献   
996.
OBJECTIVES: Autoimmune enteropathy is a rare disorder of unknown pathogenesis, characterized by protracted diarrhea, villous atrophy, and enterocyte autoantibodies. Its association with extended inflammation of the whole gastrointestinal tract is termed as generalized autoimmune gut disorder (GAGD), generally a pediatric disease of difficult management due to its association with immunodeficiency. The aim of our work is to describe the mucosal immunological basis of an adult-onset case of GAGD. METHODS: We studied an adult female with a severe inflammatory involvement of the gastrointestinal tract (stomach, small and large bowel, and liver) and antienterocyte autoantibodies. She had antibody deficiency and a predisposition to systemic autoimmunity. We analyzed, by immunohistochemistry and flow cytometry, the phenotypic and functional characteristics of her intestinal intraepithelial and lamina propria (LP) lymphocytes. RESULTS: We observed the prominent and constant presence of an unusual CD4+alphaE/beta7- Tc subset in the jejunal epithelium. Signs of the lymphocyte activation as well as the prominent lymphoid TNF-alpha production observed in the rectal mucosa support the involvement of a cell-mediated pro-inflammatory response in the pathogenesis of GAGD. CONCLUSIONS: We report the second case of an adult fulfilling all diagnostic criteria for GAGD. We propose that the activated LP CD4+ T lymphocytes, as well as those atypically located in the epithelium, may play a pathogenic role. The alphaE/beta7- IEL could constitute a diagnostic marker of intestinal autoimmunity in the cases when autoantibodies are not evidenced, and mucosal TNF-alpha might represent a novel therapeutic target in this severe disease.  相似文献   
997.
998.
BACKGROUND: Aspergillus infections of pacing systems are extremely uncommon, and most cases reported are characterized by an aggressive behavior that may lead to death of the patient. HYPOTHESIS: The study was undertaken to assess the incidence of pacemaker infection due to Aspergillus in a defined population. METHODS: A retrospective review of the case histories of all patients who underwent pacemaker implantation in the reference center for a defined population over a 13-year period was undertaken. A literature review of pacemaker infections due to Aspergillus was conducted. RESULTS: Of the 1,321 patients who required pacemaker implantation at Hospital Xeral-Calde in the Lugo region of northwestern Spain, 38 suffered a pacemaker infection. A pacemaker pocket infection due to Aspergillus fumigatus was found in two patients. Both patients had a previous history of diabetes mellitus. Cultures from pacemaker pocket inflammatory fluid yielded positive results. Following pacemaker explantation and antifungal therapy, clinical improvement was achieved. A literature review showed another five cases of pacemaker infection due to Aspergillus. However, two peculiarities were found in our patients: In both cases an etiological diagnosis was achieved prior to surgery and, to the best of our knowledge, they also constitute the first cases of pacemaker pocket infection due to Aspergillus. CONCLUSION: Although pacemaker infections due to Aspergillus species are uncommon, they should be considered in immunocompromised patients.  相似文献   
999.
A polymorphism of the human angiotensin-converting enzyme (ACE) gene has been identified in which the insertion (I) rather than the deletion (D) variant is associated with lower circulating and tissue ACE activity. ACE I allele is associated with resistance and endurance performance. Skeletal muscle metabolic efficiency is reduced in patients with heart failure and is improved by ACE inhibition. Profound muscle fatigue is a predominant and debilitating symptom in a proportion or patients with angina and normal coronary arteriograms (ANCA), and we postulated that the gene D allele might be associated with the presence of fatigue in ANCA patients. We studied 33 consecutive patients with typical ANCA who completed a validated fatigue questionnaire, and found an excess of the D allele frequency in patients with the highest fatigue scores compared to those with the lowest (64% vs. 36%; p=0.027).  相似文献   
1000.
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