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991.
Adult celiac disease followed by onset of systemic lupus erythematosus   总被引:1,自引:0,他引:1  
BACKGROUND: Celiac disease has been associated with autoimmune disease (eg, autoimmune thyroiditis) and the appearance of different autoantibodies (eg, antidouble-stranded DNA). Conversely, tissue transglutaminase antibodies have been detected in autoimmune disorders, including systemic lupus erythematosus (SLE), but cases of celiac disease with SLE have been only rarely recorded. METHODS: In this study, 246 patients with biopsy-defined celiac disease were evaluated for a prior diagnosis of SLE on the basis of American Rheumatological Association-defined clinical and serologic parameters. RESULTS: There were 6 patients with celiac disease and SLE, or 2.4%, including 4 females and 2 males. Their mean age at diagnosis of celiac disease was 44.7 years and SLE 50 years. In all patients, the diagnosis of SLE was established from 2 years to more than 10 years after the diagnosis of celiac disease, with a mean of 5.3 years. The celiac disease in all 6 patients responded to a gluten-free diet with histologic normalization of the small intestinal biopsies. Despite this small bowel biopsy response, SLE appeared later in the clinical course of the celiac disease. CONCLUSIONS: This study suggests that SLE occurs far more frequently in biopsy-defined celiac disease than is currently appreciated, and detection may be more likely if the period of clinical follow-up of the celiac disease is prolonged.  相似文献   
992.
993.
Clostridium difficile (CD), specifically its toxins, have been implicated as a risk factor for exacerbation of the inflammatory process in up to 5% of patients with ulcerative colitis or Crohn’s disease. Typical evidence of colonic changes with CD infection, including pseudomembranous exudate, are often not present; however, a severe clinical course may result, including precipitation of toxic colitis and toxic megacolon. Recently, hypervirulent CD strains have been reported raising concern for a more severe disease process in patients with underlying inflammatory bowel disease.Moreover, small bowel involvement or CD enteritis has been increasingly described, usually in those with a history of a prior colectomy or total proctocolectomy for prior severe and extensive inflammatory bowel disease. Finally, refractory or treatment-resistant pouchitis may occur with CD infection.  相似文献   
994.
The syndrome of monocytopenia, B-cell and NK-cell lymphopenia, and mycobacterial, fungal, and viral infections is associated with myelodysplasia, cytogenetic abnormalities, pulmonary alveolar proteinosis, and myeloid leukemias. Both autosomal dominant and sporadic cases occur. We identified 12 distinct mutations in GATA2 affecting 20 patients and relatives with this syndrome, including recurrent missense mutations affecting the zinc finger-2 domain (R398W and T354M), suggesting dominant interference of gene function. Four discrete insertion/deletion mutations leading to frame shifts and premature termination implicate haploinsufficiency as a possible mechanism of action as well. These mutations were found in hematopoietic and somatic tissues, and several were identified in families, indicating germline transmission. Thus, GATA2 joins RUNX1 and CEBPA not only as a familial leukemia gene but also as a cause of a complex congenital immunodeficiency that evolves over decades and combines predisposition to infection and myeloid malignancy.  相似文献   
995.
OBJECTIVES: We sought to determine the level of angiographic stenosis at which reversible regional wall motion abnormalities (RWMA) are present on exercise stress technetium-99m (Tc-99m)- gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), and whether assessments of stress and rest RWMA add incremental diagnostic information. BACKGROUND: Stress and rest gated SPECT MPI enables the detection of post-exercise stunning. Although some studies have correlated RWMA to the severity of MPI defects, only one previous study correlated RWMA on gated MPI to angiographic findings. However, this correlation excluded patients with rest perfusion defects and did not involve gating of rest images. METHODS: One hundred patients undergoing angiography within six months of exercise stress Tc-99m (sestamibi)-gated SPECT MPI (in the absence of interim cardiac events or revascularization) were recruited. Images were acquired 15 to 30 min after stress and interpreted without knowledge of the Duke treadmill score, left ventricular ejection fraction and angiographic data. RESULTS: The sensitivity of reversible RWMA for angiographic stenoses >70% was 53%, with a specificity of 100%. The presence of reversible RWMA was able to stratify patients with angiographic stenoses of 50% to 79% and 80% to 99% with a high positive predictive value. A good correlation was noted between the presence of reversible RWMA and the coronary artery jeopardy score (R = 0.49, p < 0.0001). Multivariate analysis showed that the post-stress RWMA, Duke treadmill and reversible RWMA scores were significant predictors of angiographic severity. CONCLUSIONS: Post-stress and reversible RWMA, as shown by exercise stress Tc-99m-gated SPECT MPI, are significant predictors of angiographic disease and add incremental value to MPI for the assessment of angiographic severity.  相似文献   
996.
Coeliac disease   总被引:1,自引:0,他引:1  
Increased awareness of non-classical presentations and more reliable screening tests have led to higher detection rates for coeliac disease in elderly adults. Clinical presentations are influenced largely by the long-standing course of the subclinical disease before diagnosis. In the majority of elderly patients, weight loss, diarrhoea and iron deficiency anaemia are present. With a delay in diagnosis, there are increased risks of associated autoimmune diseases, of neoplasms (mostly small bowel lymphoma) and of metabolic bone diseases. Thyroid disease is the most common autoimmune disease. Lymphoma may be the initial presentation or may complicate the clinical course of well established coeliac disease. Osteopenia is very common at presentation, can be clinically severe and require specific therapy in addition to the gluten-free diet. The high risk of complications in elderly patients with coeliac disease warrants a systematic approach in their investigation and management.  相似文献   
997.
Factors affecting HIV concordancy in married couples in four African cities   总被引:3,自引:0,他引:3  
OBJECTIVE: To determine risk factors for HIV transmission within married couples in four urban populations in sub-Saharan Africa. METHODS: Data from a cross-sectional population-based study were used. Representative random samples approximating 1000 men and 1000 women in each of four cities of Kisumu (Kenya), Ndola (Zambia), Cotonou (Benin), and Yaoundé (Cameroon), were interviewed and tested for sexually transmitted infections (STI). Married couples were identified as concordant negative, discordant, or concordant positive for each STI. After excluding concordant HIV negative couples, analysis of behavioural and STI risk factors for HIV positive concordancy was undertaken across the four cities and in each city separately where sample size allowed. RESULTS: Among 221 couples in which at least one member was HIV positive, we found that the only significant risk factor for positive HIV concordancy was herpes simplex type 2 (HSV-2) status. After adjusting for age and city of residence the odds ratio for HIV concordancy compared to couples with neither spouse HSV-2 positive was 3.4 (95% confidence interval, 0.62-18.4) for couples with one partner HSV-2 positive and 8.6 (95% confidence interval, 1.6-45.0) for couples with both partners HSV-2 positive. The same trends were seen in Kisumu and Ndola when they were analysed separately (numbers were small in the other cities). CONCLUSIONS: Although cross-sectional studies are not ideal for delineating the sequence of transmission events, this study adds to the evidence that HSV-2 is a key risk factor in promoting HIV transmission.  相似文献   
998.

Background

The fraction of cardiac arrest patients presenting with pulseless electrical activity is increasing, and it is likely that many of these patients have pseudo-electromechanical dissociation (P-EMD), a state in which there is residual cardiac contraction without a palpable pulse. The efficacy of cardiopulmonary resuscitation (CPR) with external chest compression synchronized with the P-EMD cardiac systole and diastole has not been fully evaluated.

Hypothesis

During external chest compression in P-EMD, the coronary perfusion pressure (CPP) will be greater with systolic synchronization compared with diastolic phase synchronization.

Methods

A porcine model of P-EMD induced by progressive hypoxia with peak aortic pressures targeted to 50 mmHg was used. CPR chest compressions were performed by either load distributing band or vest devices. Paired 10 s intervals of systolic and diastolic synchronization were performed randomly during P-EMD, and aortic, right atrial and CPP were compared.

Results

Stable P-EMD was achieved in 8 animals, with 2.6 ± 0.5 matched synchronization pairs per animal. Systolic synchronization was association with increases in relaxation phase aortic pressure (41.7 ± 8.9 mmHg vs. 36.9 ± 8.2 mmHg), and coronary perfusion pressure (37.6 ± 11.7 mmHg vs. 30.2 ± 9.6 mmHg). Diastolic synchronization was associated with an increased right atrial pressure (6.7 ± 4.1 mmHg vs. 4.1 ± 5.7 mmHg).

Conclusion

During P-EMD, synchronization of external chest compression with residual cardiac systole was associated with higher CPP compared to synchronization with diastole.  相似文献   
999.
We conducted a case controlled study to examine bone mineral density (BMD) in 47 women with bulimia nervosa, 51 with anorexia nervosa, 45 women recovered from past eating disorders, and 40 healthy controls. Lumbar spine and whole body BMD were measured by dual energy X‐ray absorptiometry. In contrast with previous studies, we found that subjects with active bulimia nervosa, even with no previous history of anorexia, had lower whole body and lumbar spine BMD than controls, although higher than in anorexia. Non‐traumatic spinal fractures were detected in two anorexic subjects and two bulimic subjects, but none of the controls. Assessment of BMD should be considered in patients with severe bulimia as well as anorexia nervosa. Copyright © 2004 John Wiley & Sons, Ltd and Eating Disorders Association.  相似文献   
1000.
Seven carbapenem-nonsusceptible Morganella morganii isolates, which have similar antibiotic susceptibility profiles, were isolated over a 5-month period. MICs of imipenem, meropenem, and ertapenem were 8, 1, and 0.25 to 0.5 μg/mL, respectively. Pulsed-field gel electrophoresis indicated that 6 isolates were indistinguishable or closely related. Carbapenem resistance can be transferred from M. morganii to Escherichia coli by conjugation. All M. morganii isolates and E. coli transconjugants produced KPC-2 and carried the qnrS1 gene. Production of KPC-2 mainly contributed to the carbapenem resistance in M. morganii. KPC-2-producing M. morganii clonally spread in a hospital in China.  相似文献   
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