Marc Lecuit

Breaking the wall: targeting of the endothelium by pathogenic bacteria

The endothelium lining blood and lymphatic vessels is a key barrier separating body fluids from host tissues and is a major target of pathogenic bacteria. Endothelial cells are actively involved in host responses to infectious agents, producing inflammatory cytokines, controlling coagulation cascades and regulating leukocyte trafficking. In this Review, a range of bacteria and bacterial toxins are used to illustrate how pathogens establish intimate interactions with endothelial cells, triggering inflammatory responses and coagulation processes and modifying endothelial cell plasma membranes and junctions to adhere to their surfaces and then invade, cross and even disrupt the endothelial barrier.

The Global Virus Network: Challenging chikungunya

The recent spread of chikungunya virus to the Western Hemisphere, together with the ongoing Ebola epidemic in West Africa, have highlighted the importance of international collaboration in the detection and management of disease outbreaks. In response to this need, the Global Virus Network (GVN) was formed in 2011. The GVN is a coalition of leading medical virologists in 34 affiliated laboratories in 24 countries, who collaborate to share their resources and expertise. The GVN supports research, promotes training for young scientists, serves as a technical resource for governments, businesses and international organizations, facilitates international scientific cooperation, and advocates for funding and evidence-based public policies. In response to the spread of chikungunya, the GVN formed a task force to identify research gaps and opportunities, including models of infection and disease, candidate vaccines and antivirals, epidemiology and vector control measures. Its members also serve as authoritative sources of information for the public, press, and policy-makers. This article forms part of a symposium in Antiviral Research on Chikungunya discovers the New World.

Enterobacter cloacae pyomyositis complicating chronic granulomatous disease and review of gram-negative bacilli pyomyositis

Pyomyositis is a primary purulent infection of skeletal muscles mostly described in tropical areas. Staphylococcus aureus is by far the main causative microorganisms. In temperate areas, pyomyositis more frequently affects male adults with immunodeficiency. Gram-negative bacilli pyomyositis are uncommon and occur mainly in this context of immunodeficiency. Only one case of Enterobacter cloacae pyomyositis has been reported so far. Chronic Granulomatous Disease (CGD) is a rare inherited immunodeficiency characterized by a loss of NADPH oxidase activity in phagocytic cells that favors infections due to catalase-positive microorganisms. Pyomyositis has only been described once as a complication of CGD. We report here a case of Enterobacter cloacae-associated pyomyositis of the left thigh in a patient with CGD, and review the literature on Gram-negative pyomyositis.

Diagnosis and Treatment of Listeria monocytogenes Endophthalmitis: A Systematic Review

ABSTRACT Purpose: Describe patient characteristics, treatment, and vision outcomes of Listeria monocytogenes endophthalmitis, an exceedingly rare form of listeriosis. Methods: L. monocytogenes endophthalmitis cases in human adults, located through Medline (32) and from disease surveillance centers (11). L. monocytogenes conjunctivitis and keratitis were excluded. Results: Most cases occurred in 2000–2015 (22/43), and almost all in Europe or North America (40/43). Patients were a median 61 years, 57% male (24/42) and half were immunosuppressed. Median days from entering care to diagnosis was 8 (IQR = 5–17). Only four were exogenous infections. L. monocytogenes was identified in 31/35 of anterior eye fluid samples (89%). Antibiotic regimens varied markedly (mostly ≥3 drugs). At diagnosis, most were blind in the affected eye (85%, 28/33), only a third regained normal vision (12/36). Older patients had poorer outcomes. Conclusions: Cases increased over time. Diagnostic delays were common and visual impairment often refractory to treatment, especially in older adults. The condition’s rarity and variation in treatment makes it difficult to identify optimum therapy.