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91.
Objective Hereditary paraganglioma (PGL) syndromes result from germline mutations in genes encoding subunits B, C and D of the mitochondrial enzyme succinate dehydrogenase (SDHB, SDHC and SDHD). SDHB‐related PGLs are known in particular for their high malignant potential. Recently, however, malignant PGLs were also reported among a small minority of Dutch carriers of the SDHD founder mutation D92Y. The aim of the study was to investigate which SDHD mutations are associated with malignant PGL. Design Case histories; collaborative study between referral centres in France, the USA, and the Netherlands. Patients Six unrelated patients with metastatic PGLs of either sympathetic or parasympathetic origin. Measurements Assessment of SDHD mutations underlying malignant PGL. Results Germline SDHD mutations underlying metastatic PGL were G148D, Y114X, L85X, W43X, D92Y, and IVS2+5G→A. Conclusion Our findings indicate that malignant SDHD‐related PGL is associated with several mutations besides D92Y.  相似文献   
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The case of a neonate with necrotizing enterocolitis (NEC) following intrauterine transfusions (IUTs) for Rhesus hemolytic disease (RHD) prompted us to undertake a retrospective study (1995?–?2002) to determine whether there is an association between IUT and NEC. Maternal and neonatal demographics, and details concerning IUT and definite (???Stage II) NEC, were collected. χ2 tests of association were performed. In our population 281/38?200 (0.73%) pregnancies were complicated by RHD. Fetal anemia necessitated IUT in 25/281 pregnancies. Definite NEC occurred in 59/11?814 (very low birth weight?=?1874) neonatal admissions. Except for the index case, no other neonate developed NEC following IUT. No significant association was found between IUT and NEC.  相似文献   
96.

Background:

Bhutan has attained universal child immunization since 1991. Since then, immunization coverage is maintained at high level through routine immunization, periodic National Immunization Days, and mop up campaigns. Despite high immunization coverage, every year, significant numbers of clinically suspected measles cases were reported.

Objective:

To assess the cause of continuing high “suspected measles cases” and take appropriate public health measures.

Materials and Methods:

Febrile rash outbreaks occurred in several districts in 2003. These episodes were investigated. Simultaneously, a retrospective data search revealed evidence of congenital rubella syndrome (CRS) in the country.

Results:

Thirty five percent of the tested samples were positive for rubella but none for measles. There were evidences of the presence of CRS. This was discussed in the annual health conference 2004, amongst health policy makers and district heads who recommended that a possibility of inclusion of rubella as an antigen be looked into. A nationwide measles and rubella immunization campaign was conducted in 2006 followed by introduction of rubella vaccine in the immunization schedule.

Conclusion:

Febrile rash can be caused by a host of viral infections. Following universal measles immunization, it is pertinent that febrile rash be looked in the light of rubella infections. Following the introduction of rubella vaccination in the national immunization schedule, there has been significant reduction of febrile rash episodes, cases of rubella, and congenital rubella syndrome.  相似文献   
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The management of intraductal papillary mucinous neoplasms(IPMN) is presently evolving as a result of the improved understanding of the natural history and biological behavior of the different pancreatic cystic neoplasms; and better preoperative diagnosis of these neoplasms due to advancement in preoperative diagnostic tools. International consensus guidelines for the management of IPMN were first formulated in 2006 and subsequently revised in 2012. Both these guidelines were constructed based on expert opinion and not on robust clinical data. The main limitation of the original Sendai guidelines was that it had a low positive predictive value resulting in many benign neoplasms being resected. Hence,these guidelines were revised in 2012. However,although the updated guidelines resulted in an improvement in the positive predictive value over the Sendai Guidelines,the results of several studies validating these guidelines demonstrated that its positive predictive value remained low. Furthermore,although both guidelines were associated with high negative predictive values,several investigators have demonstrated that some malignant IPMNs may be missed. Finally,it is imperative to emphasize that major considerations when managing a patient with IPMN including the patient's surgical risk,life-expectancy and even cost of investigations are not taken into account in current guidelines. The management of a patient with IPMN should be individualized and tailored according to a patient's risk benefit profile for resection vs surveillance.  相似文献   
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Catecholamine-producing tumours may arise in the adrenal medulla (phaeochromocytomas) or in extra-adrenal chromaffin cells (paragangliomas). The most specific and sensitive diagnostic test is the determination of plasma or urinary metanephrine levels. The tumour can be located by computed tomography, magnetic resonance imaging and metaiodo-benzylguanidine scintigraphy. Patients are treated by tumour resection. Phaeochromocytomas and paragangliomas may be sporadic or the result of several genetic diseases: multiple endocrine neoplasia type 2, neurofibromatosis 1, von Hippel-Lindau disease, succinate dehydrogenase-phaeochromocytoma-paraganglioma syndrome. Familial cases are diagnosed earlier and are more frequently bilateral and recurrent than sporadic cases. About 10% of tumours are malignant, either at initial surgery or during follow-up. Recurrences and malignancy are more frequent in cases with large or extra-adrenal tumours and in the succinate dehydrogenase subunit B-related phaeochromocytoma-paraganglioma syndrome. Patients should be followed up indefinitely, particularly if they have familial or extra-adrenal tumours.  相似文献   
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The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large‐sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)‐positive chronic HBV infection (n = 588), HBeAg‐positive chronic hepatitis B (n = 596), and HBeAg‐negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (= .000), with the highest (4.60 log10 IU/mL [10%‐90% confidence interval: 3.52 log10 IU/mL‐4.99 log10 IU/mL]) in patients with HBeAg‐positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg‐positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg‐negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg‐positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg‐negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease.  相似文献   
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