Kurschus et al., "IL-6 regulates neutrophil microabscess formation in IL-17A-driven psoriasiform lesions," The Journal of Investigative Dermatology, vol.
Skin biopsy from bilateral thighs and right groin at an outside institution in October 2011 displayed dense, predominantly small to medium-sized atypical lymphoid infiltrate with cerebriform nuclei and scant cytoplasm that mainly involved the dermis with minimal epidermotropism and focal Pautrier's microabscess formation.
There is an initial phase coded as "cellulitis" or "preabscess cellulitis" without pus formation or microabscess; the second phase is the "abscess" formation with macroscopic collection of pus; the third phase is the presence of "abscess cavity" with necrosis and clots, and finally, the endothelialized cavity without pus coded as "pseudoaneurysm." Furthermore, the authors support that infective endocarditis invasion may be driven more by chamber pressure than organisms which cause the disease [10].
The characteristic histological findings consisted of pseudoepitheliomatous hyperplasia and intraepithelial or dermal microabscess composed of eosinophils, along with focal ulceration, eosinohilic spongiosis and heavy infiltration of eosinophils, lymphocytes and neutrophils in dermis (figures 3 and 4).
Another pattern of IBD-associated bronchiolitis is characterized by intense acute inflammation with necrosis and microabscess formation, usually in the adjacent lung parenchyma (9) (Figure 2).
The early stage is characterized by follicular lymphoid hyperplasia, followed by microabscess formation and the development of stellate necrotizing granulomas (figure, A).