Because of the high risk associated with candida infection in premature babies and fluconazole prophylaxis is now recommended in Neonatal Intensive Care Units (NICUs) with a high incidence in fungal infections. As candida infection is difficult to prove and requires an urgent treatment, in particular to avoid central nervous system (CNS) infection, treatment is often started in high risk patients when the infection is only suspected, i.e. on clinical arguments without waiting for positive cultures (10% of cases).