Spontaneous Lethal Outbreak of Influenza A Virus Infection in Vaccinated Sows on Two Farms Suggesting the Occurrence of Vaccine-Associated Enhanced Respiratory Disease with Eosinophilic Lung Pathology.

Influenza A virus (IAV) infections in swine are usually subclinical, but they can reach high morbidity rates. The mortality rate is normally low. In this study, six vaccinated, spontaneously deceased sows revealed IAV infection and enhanced neutrophilic bronchopneumonia with unexpectedly large numbers of infiltrating eosinophils. The purpose of this study was to characterize these lung lesions with special emphasis on the phenotypes of inflammatory cells, the presence of eosinophilic peroxidase (EPO), and neutrophil extracellular traps (NETs). The number of Sirius red-stained eosinophils was significantly higher in the lungs of IAV-infected sows compared to healthy pigs, indicating a migration of eosinophils from blood vessels into the lung tissue stimulated by IAV infection. The detection of intra- and extracellular EPO in the lungs suggests its contribution to pulmonary damage. The presence of CD3+ T lymphocytes, CD20+ B lymphocytes, and Iba-1+ macrophages indicates the involvement of cell-mediated immune responses in disease progression. Furthermore, high numbers of myeloperoxidase-positive cells were detected. However, DNA-histone-1 complexes were reduced in IAV-infected sows, leading to the hypothesis that NETs are not formed in the IAV-infected sows. In conclusion, our findings in the lungs of IAV-infected vaccinated sows suggest the presence of so far unreported field cases of vaccine-associated enhanced respiratory disease.

Characterisation of apical bone lesions: Comparison of MRI and CBCT with histological findings - a case series.

PURPOSE: The aim of this case series was to compare magnetic resonance imaging (MRI) with cone beam computed tomography (CBCT) in the representation of periapical osteolyses. Based on the histological findings, the potential of MRI for further lesion characterisation was investigated. MATERIALS AND METHODS: Thirteen patients (average age: 41 ±â€…27 years) with a total of 15 periapical lesions (five molars, five premolars, and five front teeth) were examined. Lesion characterisation was based on the homogeneity/heterogeneity of the lesions, the signal intensity within the lesion compared to the surrounding tissue and differences in the signal intensities between different MRI contrast weightings. Results were compared with CBCT and histological findings. RESULTS: Although all patients presented with dental restorations, such as fixed partial dentures and filling materials, all periapical lesions could be diagnosed with either imaging modality. Histologically, 13 cysts and two apical granuloma were confirmed. In CBCT, the similar appearance of all lesions did not allow any further characterisation. In MRI, radicular cysts and granuloma could be characterised by their appearance in the MRI images with different contrast weightings. The MRI-derived characterisations were consistent with the histological findings. CONCLUSIONS: The presented study shows that the application of multi-contrast MRI may lead to better characterisation of apical lesions, thus enabling an improved patient-specific selection of the optimal treatment option. Conflict-of-interest statement: MAG, ESS, and LKS do not report any potential conflict-of-interest; EH and JU are employees of Sirona Dental Systems; VR is receiving a research grant by Sirona Dental Systems.