Betaherpesvirus assembly and egress: Recent advances illuminate the path.

The human betaherpesviruses, human cytomegalovirus (HCMV; species Human betaherpesvirus 5) and human herpesviruses 6A, 6B, and 7 (HHV-6A, -6B, and -7; species Human betaherpesviruses 6A, 6B, and 7) are highly prevalent and can cause severe disease in immune-compromised and immune-naive populations in well- and under-developed communities. Herpesvirus virion assembly is an intricate process that requires viral orchestration of host systems. In this review, we describe recent advances in some of the many cellular events relevant to assembly and egress of betaherpesvirus virions. These include modifications of host metabolic, immune, and autophagic/recycling systems. In addition, we discuss unique aspects of betaherpesvirus virion structure, virion assembly, and the cellular pathways employed during virion egress.

A Serious Complication of Illicit Silicone Injections: Latent Silicone Embolization Syndrome after Incision and Drainage of Local Injection Site.

BACKGROUND: Silicone embolization syndrome, a serious adverse effect of illicit silicone injections by laypersons, occurs when silicone particles enter the circulation and shower the lungs and other vital organs. METHODS: We review the literature on silicone embolization syndrome and describe a unique case of the syndrome that developed after a latent period of several months, upon surgical debridement of an injection site abscess. RESULTS: In the scientific literature, silicone embolization syndrome has been well described and multiple presentations have been delineated. Immediate presentation with a rapidly fatal course occurs in cases of erroneous intra-vascular injection, in which large volumes of silicone occlude pulmonary arteries and cause cor pulmonale. Insidious presentation of progressive respiratory distress and systemic inflammatory response syndrome occurs in cases of peri-vascular injection, caused by gradual vascular infiltration by smaller silicone emboli that shower pulmonary capillaries diffusely, causing alveolar hemorrhage and inflammation. Rarely, latent cases have presented months to years later upon trauma to the original site, which disrupts the sequestered siliconoma, allowing re-exposure to the immune system and the opportunity for vascular infiltration. CONCLUSIONS: To the best of our knowledge, this is the first description of silicone embolization syndrome that occurred after surgical manipulation of the site. It has important management implications for patients with a history of prior silicone injections at a site being considered for surgical intervention. Strategies for managing this potential complication include adding a regimen of daily debridement, aggressive ventilator support, and maintaining close observation in an intensive care unit (ICU) or progressive care unit (PCU) during the high-risk post-operative period. Alternatively, when possible, surgeons may avoid disruption of the siliconoma by trialing medical management of localized inflammation or using alternative procedures such as image-guided wide local excision or liposuction with fat transfer.