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251.
The need for routine supplementation of total parenteral nutrition solutions with selenium (Se) has not been clearly defined. Although clinical selenium deficiency in patients on prolonged total parenteral nutrition has been reported, it is rarely observed in the United States. We report a 19-year-old woman with cystic fibrosis who developed muscle pain and weakness after 3 months on total parenteral nutrition which was not supplemented with Se. Coincident with her onset of symptoms, markedly elevated serum creatine kinase values were observed compared to baseline levels. Subsequent evaluations revealed undetectable (less than 0.02 microgram/ml) serum and urine Se levels in this patient. In addition, electromyographic evidence of myositis and nonspecific membrane irritability was documented. Therapy with oral Se rapidly reversed her symptoms and normalized with serum creatine kinase values over a 10-day period. Prolonged treatment with Se was required to achieve normal values of Se in the serum. Patients with severe pancreatic insufficiency, such as cystic fibrosis, may be at risk for clinical Se deficiency if on prolonged total parenteral nutrition without supplementation. Elevated creatine kinase levels should alert physicians to the possibility of Se deficiency in such patients.  相似文献   
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Aim: A high diagnostic yield of colonoscopy has been reported in elderly patients, but there is no data on the yearly yield. Our aim was to detect the yearly yield of colonoscopy in elderly patients. Methods: All consecutive endoscopies in the years 1992–2009 were included. Important endoscopic diagnoses were defined as colorectal cancer (CRC), polyps, diverticuli and inflammation. Results: In total, 19 569 endoscopies were performed, of which 1706 (8.7%) were in patients age 80 years or older. The number of women was significantly higher (P < 0.001). The percentage of patients who were 80 years or older was higher than in the general population and remained stable during the study period, though there has been a proportional increase of elderly people in the general population. Inconclusive procedures were present in 106 (6.2%) elderly patients compared with 277 (1.6%) patients under 80 years of age (P < 0.001). There were no significant changes in the consecutive years. A procedure revealing no endoscopic diagnosis was observed less often in patients who were 80 years or older (P < 0.001). CRC was diagnosed in 221 (19.6%) older patients. This figure remained more or less constant each year. Polyps were seen in 448 (8.8%) patients 80 years of age or older. The percentage of patients with diverticuli and inflammation was constant. The number of patients 80 years or older with CRC and polyps rose at a lower rate than the number of older people in the general population. Conclusion: The yield of colonoscopy in patients 80 years or older was high and constant over the years. The number of tumors rose less than expected compared to the increase of elderly in the general population. Geriatr Gerontol Int 2012; 12: 298–303.  相似文献   
254.
Ectopic intrathyroidal thymic tissue is a benign lesion of nonthyroid origin occasionally found in the pediatric thyroid gland. Accurate diagnosis of such lesions is critical to avoid unnecessary biopsy or surgery. Twelve children referred to our center for the concern of thyroid nodules were found to have intrathyroidal thymic tissue. Most of the lesions had a classic sonographic appearance of a hypoechoic mass with sharp margins and multiple focal internal nonshadowing echogenicities identical to thymic tissue. Sonography and, in select cases, fine‐needle aspiration can be used to diagnose benign thymic tissue within the thyroid and avoid unnecessary surgery.  相似文献   
255.

Background

Non-invasive tests have been constructed and evaluated mainly for binary diagnoses such as significant fibrosis. Recently, detailed fibrosis classifications for several non-invasive tests have been developed, but their accuracy has not been thoroughly evaluated in comparison to liver biopsy, especially in clinical practice and for Fibroscan. Therefore, the main aim of the present study was to evaluate the accuracy of detailed fibrosis classifications available for non-invasive tests and liver biopsy. The secondary aim was to validate these accuracies in independent populations.

Methods

Four HCV populations provided 2,068 patients with liver biopsy, four different pathologist skill-levels and non-invasive tests. Results were expressed as percentages of correctly classified patients.

Results

In population #1 including 205 patients and comparing liver biopsy (reference: consensus reading by two experts) and blood tests, Metavir fibrosis (FM) stage accuracy was 64.4% in local pathologists vs. 82.2% (p < 10-3) in single expert pathologist. Significant discrepancy (≥ 2FM vs reference histological result) rates were: Fibrotest: 17.2%, FibroMeter2G: 5.6%, local pathologists: 4.9%, FibroMeter3G: 0.5%, expert pathologist: 0% (p < 10-3). In population #2 including 1,056 patients and comparing blood tests, the discrepancy scores, taking into account the error magnitude, of detailed fibrosis classification were significantly different between FibroMeter2G (0.30 ± 0.55) and FibroMeter3G (0.14 ± 0.37, p < 10-3) or Fibrotest (0.84 ± 0.80, p < 10-3). In population #3 (and #4) including 458 (359) patients and comparing blood tests and Fibroscan, accuracies of detailed fibrosis classification were, respectively: Fibrotest: 42.5% (33.5%), Fibroscan: 64.9% (50.7%), FibroMeter2G: 68.7% (68.2%), FibroMeter3G: 77.1% (83.4%), p < 10-3 (p < 10-3). Significant discrepancy (≥ 2 FM) rates were, respectively: Fibrotest: 21.3% (22.2%), Fibroscan: 12.9% (12.3%), FibroMeter2G: 5.7% (6.0%), FibroMeter3G: 0.9% (0.9%), p < 10-3 (p < 10-3).

Conclusions

The accuracy in detailed fibrosis classification of the best-performing blood test outperforms liver biopsy read by a local pathologist, i.e., in clinical practice; however, the classification precision is apparently lesser. This detailed classification accuracy is much lower than that of significant fibrosis with Fibroscan and even Fibrotest but higher with FibroMeter3G. FibroMeter classification accuracy was significantly higher than those of other non-invasive tests. Finally, for hepatitis C evaluation in clinical practice, fibrosis degree can be evaluated using an accurate blood test.
  相似文献   
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257.
BACKGROUND: The diagnostic evaluation of patients with thyroid nodules is imprecise. Despite the benefits of fine-needle aspiration (FNA), most patients who are referred for surgery because of abnormal cytology prove to have benign disease. Recent technologic and procedural advances suggest that this shortcoming can be mitigated, although few data confirm this benefit in unselected patients. METHODS: A total of 2587 sequential patients were evaluated by thyroid ultrasound and were offered ultrasound-guided FNA (UG-FNA) of all thyroid nodules that measured > or =1 cm during a 10-year period. Results of aspiration cytology were correlated with histologic findings. The prevalence of thyroid cancer in all patients and in those who underwent surgery was determined. Surgical risk was calculated. RESULTS: Tumors that measured > or =1 cm were present in 14% of patients: Forty-three percent of patients had tumors that measured <2 cm in greatest dimension, and 93% had American Joint Committee on Cancer stage I or II disease. The cytologic diagnoses 'positive for malignancy' and 'no malignant cells' were 97% predictive and 99.7% predictive, respectively. Repeat FNA of initial insufficient aspirates, as well as more detailed classification of inconclusive aspirates, improved preoperative assessment of cancer risk and reduced surgical intervention. Fifty-six percent of patients who were referred for surgery because of abnormal cytology had cancer compared with from 10% to 45% of patients historically. An analysis of operative complications from a subset of 296 patients demonstrated a 1% risk of permanent surgical complications. CONCLUSIONS: The current findings demonstrated the benefits of UG-FNA and of a more detailed classification of inconclusive aspirates in the preoperative risk assessment of thyroid nodules, supporting adherence to recently published guidelines.  相似文献   
258.
A fine-needle aspiration sample composed exclusively of Hürthle cells is interpreted as "suspicious for a follicular neoplasm, Hürthle cell type" (SFNHCT). Because some nonneoplastic Hürthle cell proliferations in Hashimoto thyroiditis (HT) mimic this cytologic pattern, we examined the positive predictive value (PPV) for malignancy of SFNHCT in patients with HT. Between 1992 and 2007, 401 patients with cytologic findings of SFNHCT were identified at 3 institutions. Histologic follow-up was available for 287 (71.6%), and malignancy was diagnosed in 69 (24.0%). Malignancy was present in 2 (PPV = 9.5%) of 21 patients with HT compared with 67 (PPV = 25.2%) of 266 patients without HT (P = .081). Although the difference in the rate of malignancy between the HT and non-HT cohorts did not reach statistical significance, the lower risk of malignancy in the HT cohort more closely approximates the risk of cases interpreted as "atypia of undetermined significance." For this reason, it might be appropriate for Hürthle cell-only aspirates from patients with HT to be categorized as either atypia of undetermined significance or SFNHCT.  相似文献   
259.
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