ABSTRACT
We would like to share a case study of a five-year-old child who complained of a painful mass on the front of his neck, with a fever of 98°F. Sometimes thyroid abscesses may be overlooked due to their rarity and are lower down on our list of differential diagnoses. Neck ultrasonography confirmed our findings. A thorough analysis of the literature showed that causal bacteria are required for almost all abscesses. However, in our instance, the aspirated fluid culture revealed no growth, indicating that the abscess was sterile. When patients present with severe neck swelling, this case report emphasizes the significance of considering thyroid abscess as one of the differential diagnoses since early detection is critical to minimize the risk of complications.
ABSTRACT
Eosinophils account for 1-3% of peripheral blood leukocytes and accumulate at sites of allergic inflammation, where they play a pathogenic role. Studies have shown that treatment with mepolizumab (an anti-IL-5 monoclonal antibody) is beneficial to patients with severe eosinophilic asthma, however, the mechanism of precisely how eosinophils mediate these pathogenic effects is uncertain. Eosinophils contain several cationic granule proteins, including Eosinophil Peroxidase (EPO). The main significance of this work is the discovery of EPO as a novel ligand for the HER2 receptor. Following HER2 activation, EPO induces activation of FAK and subsequent activation of ß1-integrin, via inside-out signaling. This complex results in downstream activation of ERK1/2 and a sustained up regulation of both MUC4 and the HER2 receptor. These data identify a receptor for one of the eosinophil granule proteins and demonstrate a potential explanation of the proliferative effects of eosinophils.
