Most patients presented risk scores that predicted high-risk mortality (APACHE II 24 and SAPS II 52). Respiratory failure was the most commonly encountered dysfunction, followed by cardiovascular, renal and hematological failures. Two patients needed dialysis. Most patients needed vasopressor and inotropic drugs. Patients presented with a serious, rapidly Oseltamivir was initiated early in all patients. Corticosteroids were administered in all patients admitted in the ICU, at a dose of methylprednisolone 2 mg/kg/day. Antibiotics were empirically administered in all patients due to clinical suspicion of bacterial coinfection. Despite early treatment, these patients had a high mortality rate, with five deaths (62.5%). The median period from admission to death was 3 days (1-8). Interestingly, three patients who died showed persistent positive rRT-PCR in nasopharyngeal swabs after 5 days of oseltamivir. Hematological evaluation showed leukocytosis (median 16 100/mm 3 ) and anemia (median hemoglobin 9.3 g/dl) in majority of cases. Also, signs of tissue hypoxia as acidosis (median pH 7.2), high levels of lactate (median 4.2 mmol/l) and low levels of base excess (median 4.5 mEq/l) were noted in patients since admission until death. Reactive protein-C ranged from 99 to 447, revealing inflammatory response associated or not with coinfection (Table 3) .