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101.

Objective

Ultrasound (US) seems a useful tool for diagnosis of calcium pyrophosphate (CPP) deposition (CPPD). We aimed to compare the performance of US and conventional radiography of the wrist for diagnosis of CPPD.

Methods

Patients with CPP crystals identified in synovial fluid (SF) (knee, hip, shoulder, ankle or wrist) were consecutively included and compared to patients without CPP crystals in synovial fluid considered as controls. As recommended, we used the term chondrocalcinosis (CC) to assess imaging features suggesting CPPD. In all patients, US and radiographic assessment of CC of the wrists was performed by two distinct operators blinded each other (one operator by imaging modality). The two operators were blinded to clinical data, SF analysis and US or radiography findings.

Results

We included 32 CPPD patients and 26 controls. Among CPPD patients, US revealed CC in 30 (93.7%) and radiography in 17 (53.1%) (P < 0.001). The sensitivity and specificity of US for the diagnosis of CPPD were 94% and 85%, respectively; the positive likelihood ratio (LR + ) was 6.1. The sensitivity and specificity of radiography were 53.1% and 100%, respectively. At joints level independently of SF analysis, US revealed CC in 35 joints without radiographic CC whereas X-rays showed CC in 3 joints without US CC. The κ coefficient between US and radiography for CC was moderate: 0.33 (0.171–0.408).

Conclusion

Our study suggests that wrist US should be considered as a relevant tool for the diagnosis of CPPD, with higher sensitivity than radiography for detecting CPP deposits.  相似文献   
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The detection of avian coronaviruses (AvCoV) in wild birds and the emergence of new AvCoV have increased in the past few years. In the present study, the pathogenicity of three AvCoV isolates was investigated in day-old chicks. One AvCoV isolated from a pigeon, which clustered with the Massachusetts vaccine serotype, and two AvCoV isolated from chickens, which grouped with a Brazilian genotype lineage, were used. Clinical signs, gross lesions, histopathological changes, ciliary activity, viral RNA detection, and serology were evaluated during 42 days post infection. All AvCoV isolates induced clinical signs, gross lesions in the trachea, moderate histopathological changes in the respiratory tract, and mild changes in other tissues. AvCoV isolated from the pigeon sample caused complete tracheal ciliostasis over a longer time span. Specific viral RNA was detected in all tissues, but the highest RNA loads were detected in the digestive tract (cloacal swabs and ileum). The highest antibody levels were also detected in the group infected with an isolate from the pigeon. These results confirm the pathogenicity of Brazilian variants, which can cause disease and induce gross lesions and histopathological changes in chickens. Our results suggest that non-Galliformes birds can also play a role in the ecology of AvCoV.  相似文献   
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Parasitology Research - Chagas disease, caused by the protozoan Trypanosoma cruzi, is considered to be a multifactorial disease associated with host and parasite genetics, which influence clinical...  相似文献   
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Parasitology Research - Among the topics related to invasion&nbsp;science, the least studied are parasite co-introduction and spillback. This leads to an uncertainty in invasion ecology...  相似文献   
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