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Hepatocellular carcinoma (HCC) is linked to environmental, dietary, and life style factors. Its incidence and distribution vary widely among ethnic groups, sex, and geographic regions. HBV and HCV Infection, liver cirrhosis, male gender, and old age are important risk factors of HCC. Variability in outcome following exposure, and the clustering of HCC within families raise the possibility that genetic factors are also involved in susceptibility to HCC. The Major Histocompatibility Complex (MHC) plays a key role in anti-virus and tumor defense. HLA polymorphism is implicated in conferring genetic susceptibility to a large number of immune-mediated diseases, including some cancers. The association between HLA class II antigen and HCC in different ethnic populations that has been reported is controversial. Therefore, the aim of this work was to study the association between HLA class II-DRB1 and DQB1 polymorphism and HCC in Egyptian patients and to investigate their role as risk factors for the development of HCC. Methods: HLA-class II (DRB1 and DQB1) typing was done by SSP for 100 subjects; 50 patients suffering from HCC (45 males and 5 females) with age range 40-64 years (51.16 years (y) +/- 6.16); and 50 normal healthy control subjects. Results: 1. A significantly increased frequency of DRB1*04, and DQB1 *02 in HCC patients versus control group (p = 0.016, and 0.032, respectively) was found; 2. A significantly decreased frequency of DQB1*06 (p = 0.032) was found; 3. A significantly increased frequency of DRB1*07 (odds ratio (OR) = 4.929) was found; and 4. A significantly decreased frequency of DRB1*15 (OR = 0.316) was seen. In conclusion, while some alleles are significantly associated with HCC (DRB1*04, DQB1*02) and others are not associated (DQB1*06); therefore, it can be concluded that the DRB1*04 and DQB1*02 alleles might be risk factors for the occurrence of HCC (OR = 4.373 and 3.807, respectively), and DQB1*06 may be a protective allele (OR = 0.259).  相似文献   
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Objectives:To assess the outcome and impact of multiple sclerosis (MS) using validated Arabic versions of the Barthel index (BI) multiple sclerosis impact scale (MSIS-29), the modified Rankin scale (mRS), and the expanded disability status scale (EDSS).Methods:A cross-sectional study conducted at King Abdulaziz Medical City in Riyadh, Kingdom of Saudi Arabia, during July-November 2017. All Saudi adult patients diagnosed with MS between 2000-2016 (269 patients) were included. Patients were contacted via phone calls and were assessed using a newly developed and validated multi-component questionnaire that included demographic data, disease course, and Arabic versions of the scales.Results:Out of 269 patients, 210 (78.2%) responded. The average patient age was 37.44±10.3 years. The majority were females (69.5%). Only, 51 (24.3%) patients reported worsening conditions. Annually, the average relapse rate was 2.28±1.91. In regard to patient outcomes, 120 (57.1%) showed no significant disability in mRS, 146 (69.5%) were ambulatory without aid in EDSS, and 185 (89.4%) were independent in BI scores. The average MSIS-29-PHYS score was 33.6±27.6 and MSIS-29-PSYCH score was 38.2±25.8. Modified Rankin scale and EDSS were significantly associated with the current use of disease-modifying therapy (DMT). Modified Rankin scale was negatively associated with delayed diagnosis. Barthel index showed significant association with medication compliance and the absence of attacks.Conclusion:Majority of patients had a favorable outcome that was linked with the use of DMT, compliance, early diagnosis, and absence of attacks.

Multiple sclerosis (MS) is a neurological disease that is singularly characterized by multifocal areas of demyelination in the central nervous system (CNS). Though its precise etiology is unclear, the pathogenesis of the disease is believed to be immune-mediated myelin destruction and, eventually, axon disruption, which is the main cause behind the progressive disability.1 Multiple sclerosis is the most common neurological autoimmune disorder in the world, with an estimated number of 2.3 million until 2013. The increase from 2.1 million in 2008 to 2.3 million in 2013 has raised not only epidemiologists’ interest and alarm but also neurologists’.2 As of Kingdom of Saudi Arabia, it was estimated that 40/100,000 is the prevalence of multiple sclerosis in 2008.3 When it comes to gender, women are generally more affected than men, estimated by a study carried out in Kingdom of Saudi Arabia.4 Affected person’s average age of onset is 30 years.The outcome and prognosis of MS do not only vary depending on a plethora of factors but are also unpredictable in nature. It is well-recognized in the literature that MS can cause disability with varying degrees, and this can have an impact on patients’ quality of life (QoL) and daily activities.5 However, the outcome is not thoroughly studied, especially in Kingdom of Saudi Arabia. To predict MS patient outcomes, conventional and physician-based validated scales are usually used, one of which is the EDSS. It mainly assesses the degree of disability and monitors the diseases’ progression but with several limitations which are documented, such as its insensitivity to change over a spectrum of 2-3 years.6 Therefore, in this study, we additionally considered other vital scores and scales that not only assess disability via the EDSS, but also the mRS. Moreover, health-related quality of life (HRQoL) is evaluated by the MSIS-29 and the BI. Such measures will help us to have a more objective and reliable endpoint regarding the patients’ outcome and survival.In this study, we hypothesised that the outcome in regard to disability and HRQoL would differ depending on the variables we took into consideration when assessing MS. Thus, the aim was to evaluate the outcome of this neurological disease that we call MS.  相似文献   
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Objectives:To study the prevalence and nature of stroke mimics (SM) among Saudi patients who came to the emergency department with a sudden neurological deficit and suspected stroke.Methods:The electronic health records from February 2016 to July 2018 of patients who were admitted to the Stroke Unit at King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Kingdom of Saudi Arabia (KAMC-RD) with a suspected stroke were all reviewed. A comparison between SM and stroke was established. Our study identified the predictors of SM by using logistic regression analysis. This study was approved by the local institutional review board.Results:Out of 1, 063 patients, 131 (12.3%) had SM. The most common causes were a peripheral vestibular disorder (27.4%) followed by psychogenic causes (24.4%). Stroke mimics were more common among younger individuals and women. Arterial hypertension, diabetes, and smoking were less likely to be found in SMs. At discharge, individuals with SM were more likely to be independent, had milder deficits, and shorter hospital stays. Predictors of SM were young age, female gender, mild deficit at presentation, and good functional status before the stroke.Conclusion:The incidence of stroke mimics is common among suspected stroke patients. Practicing physicians should consider potential diagnostic errors, particularly in the hyperacute phase of the stroke.

Stroke is one of the most common leading causes of mortality worldwide.1 Annually, the diagnosis of stroke in about 25 million people. Moreover, 6.5 million people die from stroke each year.2 Stroke is a life-threatening condition and requires immediate assessment so that patients can receive time-critical interventions such as tissue plasminogen activator (tPA). Therefore, accurate diagnosis is crucial. Sudden onset of neurological symptoms, or signs localized to brain arterial territories, are cause for suspicion of stroke. In most of these cases, a clinical assessment supported by brain computed tomography (CT) and basic laboratory tests are typically enough to make an accurate diagnosis in an emergency department. However, the misdiagnosis of stroke is relatively common. Stroke mimics (SM) are defined as acute onset of focal neurological symptoms, which later diagnosed with a non-vascular origin.3 In some patients with SM may erroneously receive intravenous thrombolysis therapy.4,5Stroke mimics are common in patients with suspected stroke.3-7 Conditions that mimic stroke include metabolic disorders such as hypoglycemia, hyperglycemia, hypernatremia, hyponatremia, uremia, metabolic encephalopathy, and hyperthyroidism.4,6,7,8 Moreover, migraine, seizure, psychological disorders, demyelinating diseases, and brain tumors may also mimic stroke.4,6-8 The characteristics and statistics about SMs among suspected cases of stroke in Saudi Arabia have not been reported. Yahia et al. reported that 15.9% of patients with suspected stroke were SMs, psychiatric etiology was the commonest.9 In this study, we estimated the prevalence, types, and predictors of SM among Saudi patients.  相似文献   
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Purpose

To compare diagnostic accuracy of CT-guided fine-needle aspiration biopsy (FNA-B) with positron emission tomography (PET)–CT for pulmonary nodules ≤ 8 mm.

Materials and Methods

A retrospective review of all CT-guided lung FNA-Bs performed between 2011 and 2014 at a single institution was undertaken to evaluate patients who had FNA-B and PET-CT imaging of nodules of ≤ 8 mm. Patients without surgical pathology or 2-year follow-up CT scans were excluded. Of 1,896 patients, 41 patients with 43 subcentimeter pulmonary nodules met study criteria. The McNemar test was used to compare FNA-B with PET-CT results.

Results

FNA-B had a sensitivity and diagnostic accuracy of 88.9% and 81.4%, respectively. PET-CT had an overall sensitivity and diagnostic accuracy of 38.9% and 46.5%, respectively. FNA-B had a significantly higher sensitivity and diagnostic accuracy for malignant nodules compared with PET-CT (P < .001). Pneumothorax rate after FNA-B was 13.9%, and chest tube insertion rate was 0%.

Conclusions

FNA-B is a safe procedure with superior sensitivity and higher diagnostic accuracy compared with PET-CT in pulmonary nodules ≤ 8mm in size.  相似文献   
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Background Context

Spinal intraoperative computer-assisted navigation (CAN) may guide pedicle screw placement. Computer-assisted navigation techniques have been reported to reduce pedicle screw breach rates across all spinal levels. However, definitions of screw breach vary widely across studies, if reported at all. The absolute quantitative error of spinal navigation systems is theoretically a more precise and generalizable metric of navigation accuracy. It has also been computed variably and reported in less than a quarter of clinical studies of CAN-guided pedicle screw accuracy.

Purpose

This study aimed to characterize the correlation between clinical pedicle screw accuracy, based on postoperative imaging, and absolute quantitative navigation accuracy.

Design/Setting

This is a retrospective review of a prospectively collected cohort.

Patient Sample

We recruited 30 patients undergoing first-time posterior cervical-thoracic-lumbar-sacral instrumented fusion±decompression, guided by intraoperative three-dimensional CAN.

Outcome Measures

Clinical or radiographic screw accuracy (Heary and 2?mm classifications) and absolute quantitative navigation accuracy (translational and angular error in axial and sagittal planes).

Methods

We reviewed a prospectively collected series of 209 pedicle screws placed with CAN guidance. Each screw was graded clinically by multiple independent raters using the Heary and 2?mm classifications. Clinical grades were dichotomized per convention. The absolute accuracy of each screw was quantified by the translational and angular error in each of the axial and sagittal planes.

Results

Acceptable screw accuracy was achieved for significantly fewer screws based on 2?mm grade versus Heary grade (92.6% vs. 95.1%, p=.036), particularly in the lumbar spine. Inter-rater agreement was good for the Heary classification and moderate for the 2?mm grade, significantly greater among radiologists than surgeon raters. Mean absolute translational-angular accuracies were 1.75?mm-3.13° and 1.20?mm-3.64° in the axial and sagittal planes, respectively. There was no correlation between clinical and absolute navigation accuracy.

Conclusions

Radiographic classifications of pedicle screw accuracy vary in sensitivity across spinal levels, as well as in inter-rater reliability. Correlation between clinical screw grade and absolute navigation accuracy is poor, as surgeons appear to compensate for navigation registration error. Future studies of navigation accuracy should report absolute translational and angular errors. Clinical screw grades based on postoperative imaging may be more reliable if performed in multiple by radiologist raters.  相似文献   
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