Antifungal drug penetration in soft tissue abscesses: a comparative analysis.

BACKGROUND: Invasive fungal infections (IFIs) are severe and difficult-to-treat infections affecting immunocompromised patients. Antifungal drug penetration at the site of infection is critical for outcome and may be difficult to achieve. Data about antifungal drug distribution in infected human tissues under real circumstances of IFI are scarce. METHODS: Multiple samples were obtained from soft tissue abscesses of a lung transplant patient with Candida albicans invasive candidiasis who underwent recurrent procedures of drainage, while receiving different consecutive courses of antifungal therapy [itraconazole (ITC), fluconazole, caspofungin]. Antifungal drug concentrations were measured simultaneously at the site of infection (surrounding inflammatory tissue and fluid content of the abscess) and in plasma for calculation of the tissue/plasma ratio (R). The concentration within the infected tissue was interpreted as appropriate if it was equal or superior to the MIC of the causal pathogen. RESULTS: A total of 30 tissue samples were collected for measurements of ITC (n = 12), fluconazole (n = 17) and caspofungin (n = 1). Variable concentrations were observed in the surrounding tissue of the lesions with median R of 2.79 (range 0.51-15.9) for ITC and 0.94 (0.21-1.37) for fluconazole. Concentrations ranges within the fluid content of the abscesses were 0.39-1.83 for ITC, 0.66-1.02 for fluconazole and 0.23 (single value) for caspofungin. The pharmacodynamic target (tissue concentration ≥ MIC) was achieved in all samples for all three antifungal drugs. CONCLUSIONS: This unique dataset of antifungal drug penetration in infected human soft tissue abscesses suggests that ITC, fluconazole and caspofungin could achieve appropriate concentrations in soft tissue abscesses.

[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.