Systemic Fungal Infections in Intensive Care Unit Patients

Systemic fungal infections are a significant and growing public health problem ,Over the past few years, major advances in healthcare have led to an unwelcome increase in the number of life-threatening infections due to true pathogenic and opportunistic fungi ,These have a significant impact on morbidity, mortality, length of hospital stay, and healthcare costs in critically ill patients in intensive care unit ( ICU).

Health care workers encounter at risk patients in ICU in various settings : including diabetes mellitus, renal insufficiency, surgery (especially abdominal surgery), the use of broad-spectrum antibiotics, parenteral nutrition, hemodialysis, mechanical ventilation, the presence of central vascular catheters, and therapy with immunosuppressive agents,Prolonged treatment with corticosteroids before ICU admission, liver cirrhosis with prolonged ICU stay (.7 days), solid organ cancer, HIV infection and lung transplantation are also considered as risk factors ,It can also occur following trauma or invasion of wounds covered with contaminated dressings, e.g. in the ICU. One outbreak of gastric mucormycosis in ICU patients reported in Spain arose in association with the use of contaminated wooden tongue depressors in critically ill patients.

Candida and Aspergillus species are the most frequent causes of healthcare-associated fungal infections in these patients, Although Candida infections are the most frequent fungal infections in ICU patients, invasive aspergillosis is associated with higher morbidity and mortality rates even in the absence of traditional risk factors,Invasive candidiasis is a highly lethal infection associated with mortality rates between 40 and 60 %. The five most common Candida species are Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei.

Accurate diagnosis of invasive fungal infection is crucial so that appropriate antifungal agents can be started rapidly. However, early diagnosis is not always easy. Microscopic examination is rapid and can be helpful but a negative result does not exclude infection. Blood cultures are positive in only 50-70 % of cases of Candida BSI, Furthermore, it can take several days before Candida is identified at the species level and antifungal susceptibility data are available but remain the gold stander in diagnosis.