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61.
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The use of insulin in elderly patients raises special considerations. Most people who develop diabetes mellitus late in life have type 2 diabetes mellitus, in which there is some residual endogenous insulin secretion. This pancreatic insulin secretion, when present, stabilises their metabolic status. However, some elderly people lose virtually all their endogenous insulin secretory capacity over time, or may even have type 1 (autoimmune) diabetes mellitus with no endogenous insulin. Generally, older patients with diabetes mellitus can be managed for years, often decades, with nutritional therapy and oral agents. More options exist now than did previously. In addition to a variety of sulfonylureas, there is metformin, troglitazone, and/or alpha-glucosidase inhibitors, that are viable options to be used before turning to insulin. The goals of insulin therapy in the elderly must be considered. When hyperglycaemia causes symptoms (polyuria, polydypsia and bodyweight loss) blood glucose levels are generally >200 mg/dl, and insulin is needed if maximal doses of oral agents have been used. Insulin is also indicated when hyperglycaemia puts patients at risk of hyperosmolar states, for example, when blood glucose is >300 mg/dl during a normal day. Clinical judgement dictates whether to use insulin to control glycaemia in the attempt to avoid long term complications such as neuropathy, retinopathy or nephropathy. In people with relatively short life expectancy, major comorbities and no sign of diabetic complications, the risk may be small. On the other hand, in patients for whom neuropathy, in particular, is a major risk, controlling glycaemia (with insulin if necessary) does reduce that risk. Most patients with type 2 diabetes mellitus can be managed with relatively simple insulin regimens thanks to their endogenous insulin secretion. A single bedtime dose of neutral protamine Hagedorn (NPH) insulin, with or without continuation of daytime oral agents, may control fasting blood glucose. A pre-mix combination of NPH and Regular insulin such as 70/30 or 50/50 may be used pre-meal. More customised, 'intensive' insulin regimens are needed when the glycaemia is unstable. Hypoglycaemia is clearly the most significant risk of insulin therapy. If mild and easily treated, it is of no real concern. On the other hand, nocturnal hypoglycaemia, and, in particular, hypoglycaemia unawareness, are clear signs that the insulin regimen should be modified. In summary, insulin therapy may be necessary, and can be used effectively, in elderly patients. However, risk:benefit considerations must be taken into account when deciding which patients to treat with insulin and what insulin regimen to use.  相似文献   
64.
Background: Enteral nutrition (EN) supports many older and disabled Americans. This study describes the frequency and cost of acute care hospitalization with dehydration and/or malnutrition of Medicare beneficiaries receiving EN, focusing on those receiving home EN. Methods: Medicare 5% Standard Analytic Files were used to determine Medicare spending for EN supplies and the proportion and cost of beneficiaries receiving EN, specifically home EN, admitted to the hospital with dehydration and/or malnutrition. Results: In 2013, Medicare paid $370,549,760 to provide EN supplies for 125,440 beneficiaries, 55% of whom were also eligible for Medicaid. Acute care hospitalization with dehydration and/or malnutrition occurred in 43,180 beneficiaries receiving EN. The most common principal diagnoses were septicemia (21%), aspiration pneumonitis (9%), and pneumonia (5%). In beneficiaries receiving EN at home, >one‐third (37%) were admitted with dehydration and/or malnutrition during a mean observation interval of 231 ± 187 days. Admitted patients were usually hospitalized more than once with dehydration and/or malnutrition (1.73 ± 1.30 admissions) costing $23,579 ± 24,966 per admitted patient, totaling >$129,685,622 during a mean observation interval of 276 ± 187 days. Mortality in the year following enterostomy tube placement was significantly higher for admitted compared with nonadmitted patients (40% vs 33%; P = .05). Conclusion: Acute care hospitalizations with dehydration and/or malnutrition in Medicare beneficiaries receiving EN were common and expensive. Additional strategies to reduce these, with particular focus on vulnerable populations such as Medicaid‐eligible patients, are needed.  相似文献   
65.
Studies on levamisole--induced agranulocytosis   总被引:1,自引:0,他引:1  
Widespread clinical trials of leavo-tetramisole (levamisole) as an immunopotentiating agent in rheumatoid arthritis, metastatic carcinoma, and immunodeficiency states have been complicated by agranulocytosis (AGC) in 2.5%-13% of patients. Other than a relationship with prolonged high dosage, very little is known regarding the pathogenesis of levamisole-induced AGC. Whereas leukoagglutination was negative, fluorochromatic microgranulocytotoxicity (GCY) tests were positive with serum from 10 of 10 acutely neutropenic patients. The antibody was IgM, reacted with 100% of unrelated granulocytes, but not with T or B lymphocytes. Some sera also reacted with monocytes and the myeloid cell line, K-562. Tests for antigen-antibody complexes or cold autoantibodies were negative. Although clinical evidence strongly suggests a haptene (drug) mechanism, in vitro mixing experiments were also negative. An alternative choice parallels the model of aldomet- induced Coombs'-positive hemolytic anemia. Finally, GCY first became positive 2-3 mo prior to the onset of AGC on two patients, suggesting the possibility of identifying those at risk well before the onset of neutropenia.  相似文献   
66.
Sheibani  K; Forman  SJ; Winberg  CD; Rappaport  H 《Blood》1983,62(6):1176-1181
Although rare cases of chronic lymphocytic leukemia (CLL) of the T-cell type have been reported, CLL is more commonly found to be a neoplastic lymphoproliferative disease of B-cell origin. In this article, we describe a patient with long-standing CLL that was immunologically shown to be of the B-cell type, who, during the course of his disease, developed cutaneous T-cell lymphoma (CTCL), which was shown to be of the helper/inducer subtype. The neoplastic lymphoid cells in the skin infiltrate differed morphologically and immunologically from those in the peripheral blood. The occurrence of CTCL during this patient's clinical course represents a second neoplasm arising from a different cell line, rather than a tissue manifestation of the patient's CLL. To our knowledge, this is the first report in which the occurrence of CTCL is documented in a patient with immunologically known B-cell CLL. In addition to establishing the presence of B-cell CLL and CTCL of the helper/inducer T-cell type in the same patient, this case report demonstrates the usefulness and necessity of evaluating lymphoproliferative disorders by means of a multidisciplinary approach.  相似文献   
67.
The present study in patients with aplastic anemia was undertaken to determine whether exposure of recipients to donor blood products 24 hr before preparation with cyclophosphamide (1) enhanced the rate of sustained engraftment of marrow from HLA-identical siblings as suggested by animal experiments, (2) increased the rejection rate, in particular in transfused patients who may already have been exposed to donor antigens by blood products, or (3) was of no relevance to the outcome of transplantation of marrow from HLA-identical siblings. One- hundred fifty-five patients were studied, of whom 78 received blood products from the marrow donor 24 hr before cyclophosphamide and 77 did not. A binary logistic regression analysis was applied to the data, simultaneously considering five previously known risk factors for rejection. Results showed that preceding transfusion of donor blood products had neither a significant beneficial nor detrimental effect on the incidence of sustained engraftment.  相似文献   
68.
Marrow harvesting from normal donors   总被引:4,自引:2,他引:4  
The experience at a single institution in harvesting marrow for allogeneic transplantation on 1,270 occasions from 1,160 normal donors is presented in detail, together with an analysis of all the donor complications. Four donors were less than 2 years old, and the youngest was 6 1/2 months. No special difficulties were encountered with these young donors. Hospitalization time was three days or less for 99% of the procedures. Six donors had life-threatening complications; three of a cardiopulmonary and two of an infectious nature, and one cerebrovascular embolic episode. Significant operative site morbidity, usually transient neuropathies, occurred in ten procedures. Ten percent of the donations were associated with transient postoperative fever of unknown origin. Increasing donor age was associated with a reduction of the cellularity of the marrow harvest. The use of stored autologous blood permitted the avoidance of blood bank transfusion in 81% of males, 69% of females, and 50% of children. It was concluded that the procedure was associated with a very low risk of complication, but that the involvement of normal donors in such an operation justifies stringent monitoring.  相似文献   
69.
From 1990 to 1993 we performed a prospective study of busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 30 patients with refractory anemia (RA) undergoing related (n = 17) or unrelated (n = 13) donor marrow transplantation. Nineteen patients survive disease free (63% 3- year actuarial disease-free survival [DFS]) and no patient relapsed. These results were compared to those of 38 historical controls with RA treated with cyclophosphamide and total body irradiation, of whom 22 are disease-free survivors and 1 relapsed. After correcting for significant variables between the two treatment groups, we found no statistically significant difference in outcome based on preparative regimen. Combining data from these 68 patients plus 2 additional patients with RA treated before 1993 with busulfan and cyclophosphamide, we identified four variables independently associated with improved survival: younger age, shorter disease duration, lower neutrophil count pretransplant, and lower hematocrit pretransplant. We also found that 15 patients 40 to 55 years of age had a 46% 3-year actuarial DFS and 26 patients receiving unrelated or mismatched related donor marrow had a 50% 3-year actuarial DFS. We conclude that there does not appear to be any significant difference in outcome based on preparative regimen in this patient population. In addition, allogeneic bone marrow transplantation may be a reasonable approach to therapy of RA early after diagnosis. However, whether early intervention with transplantation prolongs survival over that expected without transplantation cannot be ascertained with certainty from available data.  相似文献   
70.
Sanders  JE; Thomas  ED; Buckner  CD; Doney  K 《Blood》1987,70(1):324-326
Fifty-seven children between the ages of 3 and 17 years with acute lymphoblastic leukemia (ALL) in chemotherapy-induced second bone marrow remission were given cyclophosphamide, total body irradiation, and bone marrow transplants from HLA-matched donors. Sixteen died of transplant- related complications. Eighteen relapsed between 56 and 833 days after transplantation, and 16 died of leukemia. Two survive in remission off treatment following chemotherapy. Twenty-three survive in continuous remission from 1.4 to 10.4 years after transplantation and the actuarial analysis shows disease-free survival of 40% with a plateau extending from 2.5 to 10.4 years.  相似文献   
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