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831.
832.
833.
Few long-term single-center studies have addressed the outcome of patients with papillary urothelial neoplasms of low malignant potential. Our study evaluates the behavior of these tumors occurring as primary urinary bladder lesions. For this purpose, 34 primary in-house cases diagnosed and treated between 1998 and 2008 were identified from our medical records. Upon review, 3 cases were upgraded to noninvasive low-grade urothelial carcinomas and excluded from further evaluation. During follow-up (range, 3-108 months; mean, 42 months), 13 patients developed recurrences; and 9 patients progressed to a noninvasive higher grade lesion (8 to low-grade and 1 to high-grade urothelial carcinomas). None of our patients developed stage progression (>pTa) or died of bladder cancer. Size of the primary tumor was associated with the risk of recurrence (P = .043), whereas the number of episodes of recurrence was associated with the likelihood of grade progression (P = .034). In conclusion, recurrences were observed in 42% of all our patients, with a grade progression rate of 29%. None of our patients developed invasive carcinoma or died as a consequence of their disease. Considering the low but definitive risk of recurrence and grade progression, appropriate clinical follow-up of patients with primary papillary urothelial neoplasm of low malignant potential is warranted.  相似文献   
834.
The incidence of type 1 diabetes is rising worldwide, particularly in young children. Since type 1 diabetes is preceded by autoimmunity to islet antigens, there must be a consequent increase in the incidence of islet autoimmunity in young children or a more rapid rate of progression to diabetes once islet autoimmunity initiates. This study was to determine whether the incidence of islet autoimmunity or the rate of progression from autoimmunity to diabetes onset has changed over a 20-year period in children genetically predisposed to type 1 diabetes. Between 1989 and 2010, children who were first-degree relatives of patients with type 1 diabetes and who were born in Germany were prospectively followed from birth without intervention. A total of 324 children (BABYDIAB study) born between 1989 and 2000 and 216 children (TEDDY study) born between 2004 and 2010 with matched HLA genotypes were recruited before age 3 months and included for analysis. Children were followed for the development of autoantibodies to insulin, GAD, and IA-2, and for progression to diabetes. The cumulative frequency of diabetes by age 4 years was 2.5% (95% CI 0.8-4.2%) in BABYDIAB children and 6.2% (95% CI 2.3-10.1%) in TEDDY children (p = 0.03). The cumulative frequency of islet autoantibodies by age 4 years was similar in the children from both studies (11.3% vs 13.9%). Progression to diabetes from the development of islet autoantibodies was markedly increased in autoantibody-positive children from the more recently recruited TEDDY cohort (50% progression within 85.2 months for BABYDIAB children vs 9.6 months for TEDDY children; p = 0.009), also if children were further selected on the basis of high-risk HLA genotypes or the development of autoantibodies to multiple islet antigens (p = 0.01). The findings suggest that recent increasing incidence of type 1 diabetes in young children could be due to weakening of mechanisms that normally regulate autoimmune destruction of islet beta cells.  相似文献   
835.
Progression of chronic renal failure in children with dysplastic kidneys   总被引:1,自引:1,他引:0  
The aim of this study is to describe progression of chronic renal failure (CRF) in children with renal malformations and to study factors influencing this progression. We reviewed retrospectively 176 children with CRF secondary to renal dysplasia, reflux nephropathy or renal obstruction with at least 5 years of follow-up. Serum creatinine was recorded at least every third month, and an estimated glomerular filtration rate (eGFR) was calculated. Number of febrile urinary tract infections (UTI), blood pressure, albuminuria (UaUc), and number of functioning kidneys was also recorded. We found that the development of renal function could be separated into three time periods: (1) During the first years of life, 82% of the children showed early improvement of their kidney function, which lasted until a median age of 3.2 years (median improvement 6.3 ml/year). (2) From the age of 3.2 years until 11.4 years, 52.5% of the studied children showed a stable kidney function, whereas in 47.5%, kidney function immediately started to deteriorate. (3) Around puberty, 42.9% started deterioration in kidney function, whereas 57.1% even after puberty showed a stable function. Patients with UaUc >200 mg/mmol deteriorated faster (−6.5 ml/min per 1.73 m2 per year compared with −1.5 ml/min per 1.73 m2 per year) in those with UaUc <50 mg/mmol. Children with more than two febrile UTIs, hypertension or an eGFR at onset of less than 40 ml/min per 1.73 m2 deteriorated faster than the others. Most children experienced early improvement of kidney function. The further prognosis, early or late deterioration of kidney function or stable function during the whole follow-up, was related to albuminuria, number of febrile UTIs, eGFR at onset of deterioration, hypertension and puberty.  相似文献   
836.
If nephrolithiasis (NL) promotes progression to end stage renal disease (ESRD), requiring renal replacement therapy, one might expect a higher prevalence of pre-ESRD stones among ESRD versus non-ESRD subjects. We compared the prevalence of pre-ESRD stones in an African-American (AA) hemodialysis (HD) population to the estimated stone prevalence in a nationally representative cohort of AA persons as obtained by the Third National Health and Nutrition Survey (NHANES III). Face-to-face questionnaires were administered to a sample of 300 AA HD patients undergoing dialysis therapy at the University of Chicago to determine pre-ESRD NL prevalence. All data on pre-ESRD stone prevalence was confirmed by documented medical history, radiology and laboratory findings, where available. Prevalence of pre-ESRD NL in AA HD patients was 8.3% versus 2.8% in the age, race and sex adjusted NHANES III population (P < 0.001). After adjustment for age and sex, it was estimated that the prevalence of pre-ESRD kidney stones among AA HD patients is significantly higher than the prevalence of kidney stones found in the general AA population.  相似文献   
837.
AIMS/HYPOTHESIS: To estimate the 1-year progression rates from both IFG and IGT to diabetes in individuals identified in a pragmatic diabetes screening programme in general practice (the ADDITION Study, Denmark [Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen-Detected Diabetes in Primary Care]). METHODS: Persons aged 40-69 years were screened for type 2 diabetes based on a high-risk, stepwise strategy. At baseline, anthropometric measurements, blood samples and questionnaire data were collected. A total of 1,160 persons had IFG or IGT at baseline: 811 (70%) accepted re-examination after 1 year. Glucose tolerance classification was based on the 1999 WHO definition. At follow-up, diabetes was based on one diabetic glucose value of fasting blood glucose or 2-h blood glucose. RESULTS: At baseline, 308 persons had IFG and 503 had IGT. The incidence of diabetes was 17.6 and 18.8 per 100 person-years in the two groups, respectively. CONCLUSIONS/INTERPRETATION: IFG and IGT identified in general practice during a stepwise, high-risk screening programme for type 2 diabetes have high 1-year progression rates to diabetes. Consequently, intensive follow-up and intervention strategies are recommended for these high-risk individuals.  相似文献   
838.
Aims/Hypothesis The aims of this study were (1) to determine the prevalence and rate of progression in diabetes secondary to mitochondrial DNA (mtDNA) mutations; and (2) to determine whether percentage heteroplasmy predicts clinical outcome in patients carrying the m.3243A>G mutation. Methods We prospectively assessed 242 patients attending a specialist neuromuscular clinic using a validated mitochondrial disease rating scale. Retrospective clinical data on these patients from up to 25 years of follow-up were also included. Percentage heteroplasmy in blood, urine and muscle was determined for the m.3243A>G group and correlated against clinical features. Results Patients carrying the m.3243A>G mutation formed the largest group of patients with diabetes (31/81 patients). The highest prevalence of diabetes was in the m.12258C>A group (2/2 patients), the lowest in the multiple mtDNA deletions group (3/43 patients). The earliest age of onset was in the m.3243A>G group (37.9 years) with the highest age of presentation in the multiple deletion group (56.3 years). Of patients presenting with m.3243A>G, 12.9% required insulin; an additional 32.3% progressed to insulin requirement over a mean of 4.2 years after presentation. Percentage heteroplasmy in blood, urine or muscle did not predict progression of diabetes or risk of developing complications. Early age of presentation with diabetes did predict poor clinical outcome. Conclusions/Interpretation Although patients carrying the m.3243A>G mutation account for the majority of cases of diabetes secondary to mtDNA mutations, several other genotypes are also associated with the development of diabetes, some with high penetrance. All show a gradual progression to insulin requirement. Percentage heteroplasmy is a poor predictor of severity of diabetes in the m.3243A>G group.  相似文献   
839.

Background

Randomized trials have shown an improvement in progression-free survival rates with adjuvant radiation therapy (ART) after radical prostatectomy for patients with a high risk of cancer recurrence. Less is known about the relative advantages and disadvantages of initial observation with delayed salvage radiation therapy (SRT).

Objective

To examine the results of SRT in a large single-surgeon radical prostatectomy series.

Design, Setting, and Participants

From a radical prostatectomy database, we identified 859 men with positive surgical margins (SM+), extracapsular tumor extension (ECE), or seminal vesicle invasion (SVI) who chose to defer ART. Following a period of initial observation, 192 ultimately received SRT for prostate-specific antigen (PSA) progression.

Measurements

Survival analysis was performed to examine the outcomes of initial observation followed by SRT.

Results and Limitations

In patients with SM+/ECE and SVI, the 7-yr PSA progression-free survival rates with observation were 62% and 32%, respectively. Among those who had PSA progression, 56% and 26%, respectively, maintained an undetectable PSA for 5 yr after SRT. The long-term rates of undetectable PSA associated with an SRT strategy were 83% and 50% for men with SM+/ECE and SVI, respectively. In the subset of 716 men who did not receive any hormonal therapy, the corresponding long-term rates of undetectable PSA were 91% and 75%, respectively.

Conclusions

Following radical prostatectomy, initial observation followed by delayed SRT at the time of PSA recurrence is an effective strategy for selected patients with SM+/ECE. Some patients with SVI may also benefit from this strategy. However, additional prospective studies are necessary to further examine the survival outcomes following SRT.  相似文献   
840.
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