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Background

The American Academy of Orthopedic Surgeons clinical practice guideline currently recommends repeat joint aspiration when workup of periprosthetic joint infection (PJI) reveals conflicting data. This guideline is based on a single study of 31 patients published 25 years ago. We sought to determine the correlation between first and second aspirations and factors that may play a role in variability between them.

Methods

Sixty patients with less than 90 days between aspirations and no intervening surgery were identified at our institution and classified by Musculoskeletal Infection Society (MSIS) criteria as infected, not infected, or not able to determine after both aspirations. Culture results from both aspirations were recorded. The rates of change and correlation in clinical diagnosis and culture results between aspirations were determined.

Results

Repeat aspiration changed the diagnosis in 26 cases (43.3%, 95% confidence interval 31.6-55.9, kappa coefficient 0.32, P < .001), and the culture results in 25 cases (41.7%, 95% confidence interval 30.1-54.3, kappa coefficient 0.27, P < .01). Among patients initially MSIS negative, the proportion who changed to MSIS positive was greater for those with a history of prior PJI compared to those without (66.7% vs 0%, P < .05), and the first aspiration mean volume was higher for those changed to MSIS positive compared to those that remained MSIS negative (12.0 vs 3.0 mL, P < .01). Among patients initially MSIS positive, the proportion of patients who changed to MSIS negative was greater for those with a history of adverse local tissue reaction (ALTR) to metal debris compared to patients without suspicion of ALTR (100% vs 7.7%, P < .05).

Conclusion

Repeat aspiration is particularly useful in patients with conflicting clinical data and prior history of PJI, suspicion of ALTR, or with high clinical suspicion of infection.  相似文献   
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目的 研究机械通气下使用密闭式吸痰的婴幼儿吸痰前不常规提高吸氧浓度对患儿氧合的影响。 方法 通过对64例婴幼儿(192次吸痰操作),吸痰前不进行提高氧浓度的操作进行观察,分别记录患儿吸痰前平静时、吸痰中、吸痰后1min时患儿SpO2的值和SpO2恢复至平静时所需的时间。 结果 吸痰前不提高氧浓度,患儿在吸痰时及吸痰后SpO2相对于吸痰前变化不明显。吸痰后SpO2恢复至平静时的时间为18.00(5.25-30.00)s。 结论 吸痰前SpO2稳定,并排除痉咳、心脏分流等原因的患儿,密闭式吸痰前没有必要常规给予提高吸氧浓度的操作。  相似文献   
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The 2019 coronavirus pandemic, which started in Wuhan, China, spread around the globe with dramatic and lethal effects. From the initial Chinese epicenter, the European diaspora taxed the resources of several countries and especially those of Italy, which was forced into a complete social and economic shutdown. Infection by droplets contaminating hands and surfaces represents the main vehicle of diffusion of the virus. The common and strong efforts to contain the pandemic have relevant effects on the management of samples from histopathology laboratories. The current commentary reports and focuses on the protocols and guidelines in use at a large tertiary Italian hospital that accordingly are proposed for adoption in Italian laboratories as a potential model for national guidelines for the coronavirus emergency.  相似文献   
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Objective: Molecular testing of thyroid nodules becomes important for improving the accuracy of fine-needle aspiration biopsy (FNAB). This study aimed to investigate the diagnostic utility of BRAF, NRAS, and TERT promoter mutation in thyroid nodules at Dharmais Cancer Hospital.Methods: We performed a prospective diagnostic study involving 50 patients with thyroid nodules who needed surgery between September 2013 and August 2014. Mutational hotspots in BRAF exon 15, NRAS exon 3, and TERT promoter region were analyzed by Sanger sequencing from FNAB specimens. Cytology and molecular data were compared to histopathology results.Result: Of the 50 cases included in the analysis, 39 cases (78%) were thyroid malignancies. Mutations of BRAF, NRAS, and TERT promoter were detected in 31% (12/39), 18% (7/39), and 13% (5/39) cases, respectively. BRAF and NRAS mutations were found mutually exclusive, while all of TERT promoter mutation was found coexistent either with BRAF (40%) or NRAS (60%). The combination of FNAB cytology and molecular testing resulted in 69% sensitivity, 100% specificity, 100% positive predictive value, 48% negative predictive value, and 76% accuracy.Conclusion: Molecular testing of BRAF, NRAS, and TERT mutations improve the sensitivity of thyroid FNAB and is beneficial for more definitive treatment in selective cases. However, the NPV is relatively low to avoid the need for diagnostic surgery. Therefore, further studies to identify more sensitive methods and more comprehensive molecular markers in the diagnosis of thyroid nodules are needed.  相似文献   
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Ansa-to-recurrent laryngeal nerve (ANSA-RLN) reinnervation procedures are now often first-line treatments for some children with unilateral vocal fold immobility. Although many describe that children with prolonged denervation and true vocal fold atrophy should not undergo this procedure, there has been no gold-standard means of identifying true denervation. Here, we describe a novel technique using evoked vagal electromyography to predict degree of chronic nerve injury prior to recurrent laryngeal nerve reinnervation in children. This is a simple, readily available technique that may play an important role in predicting likelihood of success with pediatric ANSA-RLN reinnervation. Laryngoscope, 130:747–751, 2020  相似文献   
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