- Active infection defined by the presence of at least two of the criteria for systemic inflammatory response syndrome (SIRS), necessarily including neutrophilia in the hemogram. In case of a positive culture, the presence of only one of the SIRS criteria is considered sufficient for the infection diagnosis. SIRS is defined by: temperature >38º or <36º C, heart beat >90 beats/min, breath frequency >20 resp/min, white cell count >12000/mm3 or <4000/mm3 or >6% of immature cells.