Clinical Microbiology and Infection最新文献

Background: Overdiagnosis of urinary tract infections (UTIs) is one of the most common reasons for the unnecessary use of antibiotics in nursing homes, increasing the risk of missing serious conditions. Various decision tools and algorithms aim to aid in UTI diagnosis and the initiation of antibiotic therapy for residents. However, due to the lack of a clear reference standard, these tools vary widely and can be complex, with some requiring urine testing. As part of the European-funded IMAGINE project, aimed at improving antibiotic use for UTIs in nursing home residents, we have reviewed the recommendations.

Objectives: This review provides a comprehensive summary of the more relevant tools and algorithms aimed at identifying true UTIs among residents living in nursing homes and discusses the challenges in using these algorithms based on updated research.

Sources: The discussion is based on a relevant medical literature search and synthesis of the findings and published tools to provide an overview of the current state of improving the diagnosis of UTIs in nursing homes.

Content: The following topics are covered: prevalence of asymptomatic bacteriuria, diagnostic challenges, clinical criteria, urinary testing, and algorithms to be implemented in nursing home facilities.

Implications: Diagnosing UTIs in residents is challenging due to the high prevalence of asymptomatic bacteriuria and nonspecific urinary tract signs and symptoms among those with suspected UTIs. The fear of missing a UTI and the perceived antibiotic demands from residents and relatives might lead to overdiagnosis of this common condition. Despite their widespread use, urine dipsticks should not be recommended for geriatric patients. Patients who do not meet the minimum diagnostic criteria for UTIs should be evaluated for alternative conditions. Adherence to a simple algorithm can prevent unnecessary antibiotic courses without compromising resident safety.

Background: Advanced HIV disease (AHD) is increasing, with late presentation accounting for half of newly diagnosed people with HIV (PWH) in Europe. Mortality in late-presenting PWH remains high, and Mycobacterium avium complex (MAC) disease, among other opportunistic infections, presents several diagnostic and treatment challenges that lead, ultimately, to a poor clinical outcome.

Objectives: We aimed to provide guidance on the diagnosis and treatment of disseminated MAC disease (dMACd) in PWH.

Sources: We performed a review of original articles, meta-analyses, and systematic reviews retrieved from PubMed.

Content: We reviewed and discussed the most challenging steps in the management of PWH with AHD and dMACd: the current epidemiology in the era of effective antiretroviral treatment; clinical presentation and interpretation of symptoms in the context of other opportunistic infections and immune reconstitution; diagnosis, sampling, and timing to reach a definitive diagnosis; prophylaxis, treatment options, and indications for discontinuing MAC treatment; future perspectives; and the role of rifamycins in the treatment of dMACd.

Implications: Despite the widespread availability of effective antiretroviral treatment, dMACd still represents a major cause of morbidity and mortality in PWH with AHD. Residual challenges are mainly related to the difficulties and timing required to reach a definitive diagnosis, and the discussion regarding the role of rifamycins in the treatment of dMACd is still open.

Background: Clostridioides difficile (C. difficile) remains the leading cause of healthcare-associated diarrhoea, posing treatment challenges because of antibiotic resistance and high relapse rates. Faecal microbiota transplantation is a novel treatment strategy to prevent relapses of C. difficile infection (CDI), however, the exact components conferring colonization resistance are unknown, hampering its translation to a medicinal product. The development of novel products independent of antibiotics, which increase colonization resistance or induce protective immune mechanisms is urgently needed.

Objectives: To establish a framework for a Controlled Human Infection Model (CHIM) of C. difficile, in which healthy volunteers are exposed to toxigenic C. difficile spores, offering the possibility to test novel approaches and identify microbiota and immunological targets. Whereas experimental exposure to non-toxigenic C. difficile has been done before, a toxigenic C. difficile CHIM faces ethical, scientific, logistical, and biosafety challenges.

Sources: Specific challenges in developing a C. difficile CHIM were discussed by a group of international experts during a workshop organized by Inno4Vac, an Innovative Health Initiative-funded consortium.

Content: The experts agreed that the main challenges are: developing a clinically relevant CHIM that induces mild to moderate CDI symptoms but not severe CDI, determining the optimal C. difficile inoculum dose, and understanding the timing and duration of antibiotic pretreatment in inducing susceptibility to CDI in healthy volunteers.

Implications: Should these challenges be tackled, a C. difficile CHIM will not only provide a way forward for the testing of novel products but also offer a framework for a better understanding of the pathophysiology, pathogenesis, and immunology of C. difficile colonization and infection.