Invasive fungal infections in the intensive care unit: a multicentre, prospective, observational study in Italy (2006-2008).

Critically ill patients admitted to intensive care units (ICU) are highly susceptible to healthcare-associated infections caused by fungi. A prospective sequential survey of invasive fungal infections was conducted from May 2006 to April 2008 in 38 ICUs of 27 Italian hospitals. A total of 384 fungal infections (318 invasive Candida infections, three cryptococcosis and 63 mould infections) were notified. The median rate of candidaemia was 10.08 per 1000 admissions. In 15% of cases, the infection was already present at the time of admission to ICU. Seventy-seven percent of Candida infections were diagnosed in surgical patients. Candida albicans was isolated in 60% of cases, Candida glabrata and Candida parapsilosis in 13%, each. Candida glabrata had the highest crude mortality rate (60%). Aspergillus infection was diagnosed in 32 medical and 25 surgical patients. The median rate was 6.31 per 1000 admissions. Corticosteroid treatment was the major host factor. Aspergillosis was demonstrated to be more severe than candidiasis as the crude mortality rate was significantly higher (63% vs. 46%), given an equal index of severity, Simplified Acute Physiology Score (SAPS-II). The present large nationwide survey points out the considerable morbidity and mortality of invasive fungal infections in surgical as well as medical patients in ICU.

Interleukin-18 is an essential element in host resistance to experimental group B streptococcal disease in neonates.

Previous studies demonstrated that interleukin-12 (IL-12)-dependent gamma interferon (IFN-gamma) responses have a major role in restricting in vivo bacterial growth during infection of mice with group B streptococci (GBS), important human pathogens. Like IL-12, IL-18 is a potent IFN-gamma inducer. The role of IL-18 in experimental GBS infection was investigated here. Significant elevations of IL-18 levels over baseline values were detected in plasma samples from neonatal mice rendered septic with GBS. Neutralization of IL-18 significantly increased mortality and bacterial burden (P < 0.05). In contrast, administration of recombinant IL-18 (rIL-18) before or after GBS challenge remarkably improved survival and decreased blood colony counts, in association with increased IFN-gamma production by spleen cells. The beneficial effects of rIL-18 were counteracted by administration of neutralizing anti-IFN-gamma monoclonal antibodies, indicating that the effects of IL-18 were mediated by IFN-gamma. Finally, low rIL-18 doses that had no effect of their own on bacterial burden could act in synergy with rIL-12 to protect neonatal mice during GBS infection. Collectively, our data indicate that IL-18 responses have an important role in host defenses against GBS and that rIL-18 may be useful in alternative strategies to treat neonatal GBS disease.