[Respiratory infections: when a horse is actually a zebra]. / Infections respiratoires : quand un cheval est en fait un zèbre.

While most episodes of community-acquired pneumonia are caused by Streptococcus pneumoniae and respiratory viruses, other atypical pathogens can also be responsible for lung infections. The Infectious Diseases Service of the Lausanne University Hospital (CHUV) organizes an annual meeting aimed at general practitioners, during which interesting clinical cases are presented. In this article, we summarize five cases of community-aquired respiratory infection due to atypical pathogens that were presented during the 2023 meeting, each with a particular teaching point. Although these infections are rare, expanding the differential diagnosis in cases of suboptimal response to therapy or particular exposures is warranted.

La plupart des épisodes de pneumonie acquise en communauté sont causés par Streptococcus pneumoniae et des virus respiratoires, mais d'autres agents pathogènes atypiques peuvent également être responsables d'infections pulmonaires. Le Service des maladies infectieuses du Centre hospitalier universitaire vaudois (CHUV) organise une réunion annuelle destinée aux médecins généralistes, au cours de laquelle des cas cliniques intéressants sont présentés. Dans cet article, nous résumons cinq cas d'infections respiratoires communautaires dus à des agents pathogènes atypiques présentés lors de la réunion de 2023, chacun avec un enseignement particulier. Bien que ces infections soient rares, élargir le diagnostic différentiel en cas de réponse thérapeutique suboptimale ou d'expositions particulières est justifié.

Association of persistent positive blood cultures and infective endocarditis: A cohort study among patients with suspected infective endocarditis.

OBJECTIVES: To ascertain whether infective endocarditis (IE) was associated with persistent bacteraemia/candidaemia among patients with suspected IE. METHODS: This study included bacteraemic/candidaemic adult patients with echocardiography and follow-up blood cultures. Persistent bacteraemia/candidaemia was defined as continued positive blood cultures with the same microorganism for 48 h or more after antibiotic treatment initiation. Each case was classified for IE by the Endocarditis Team. RESULTS: Among 1962 episodes of suspected IE, IE (605; 31%) was the most prevalent infection type. Persistent bacteraemia/candidaemia was observed in 426 (22%) episodes. Persistent bacteraemia was more common among episodes with Staphylococcus aureus bacteraemia compared to episodes with positive blood cultures for other pathogens (32%, 298/933 vs 12%, 128/1029; P < 0.001). Multivariable analysis demonstrated that cardiac predisposing factors (aOR 1.84, 95% CI 1.31-2.60), community or non-nosocomial healthcare-associated (2.85, 2.10-3.88), bacteraemia by high-risk bacteria, such as S. aureus, streptococci, enterococci or HACEK (1.84, 1.31-2.60), two or more positive sets of index blood cultures (6.99, 4.60-10.63), persistent bacteraemia/candidaemia for 48 h from antimicrobial treatment initiation (1.43, 1.05-1.93), embolic events within 48h from antimicrobial treatment initiation (12.81, 9.43-17.41), and immunological phenomena (3.87, 1.09-1.78) were associated with infective endocarditis. CONCLUSIONS: IE was associated with persistent bacteraemia/candidaemia, along with other commonly associated factors.