Classification of the variables for each component of PIRO
– For the P component we selected demographic variables
– sex – male or female
– age in years, and
– underlying disease variables including presence of
chronic hepatic failure defined as biopsy-proven cirrhosis with portal hypertension; episodes of past upper GI bleeding attributed to portal hypertension; or prior episodes of hepatic failure, encephalopathy, or coma.
– chronic renal failure defined as patient r eceiving chronic dialysis or with a basal value of seric creatinine equal or higher than 2 mg/dl.
– chronic cardiovascular failure defined as New York Heart Association (NYHA) class III or
IV heart failure.
– chronic respiratory failure defined as chronic restrictive, obstructive, or vascular lung disease resulting in severe exercise restriction (ie, unable to climb stairs or perform household duties); or documented chronic hypoxia needing oxygen therapy at home, or severe pulmonary hypertension (>40 mmHg) or right cardiac insuficiency secondary to chronic lung disease.
– chronic hematological failure defined as any malignant haematological disease or chronic neutropenia ( neutrophils equal or less than 1000/dl lasting 3 or more months) or neutrophils count in blood equal or less than 1000/dl.
– metastatic cancer defined as metastasis proven by CT scan, surgery or any other method.
– immunocompromised state defined as short and long course corticosteroid therapy, chemotherapy, radiotherapy, HIV positive, AIDS
Definitions for the Immunocompromised state:
Long course corticosteroid therapy - equivalent to at least 0,2 mg/Kg/day during at least 3 months in the 12 precedent months
Short course corticosteroid therapy – equivalent to 1 mg/Kg/day of prednisone during at least 1 week in the 3 precedent months.
Chemotherapy – has done any sort of chemotherapy in the 12 precedent months
Radiotherapy – has done any sort of radiotherpay in the 12 precedent months
HIV positive – positive for HIV without criteria for AIDS
AIDS – positive for HIV and with criteria for AIDS according to center for disease control (CDC), i.e., pneumonia to Pneumocystis jirovecii, Kaposi sarcoma, limphome, tuberculosis or toxoplasma infection.
– For the I component we selected variables that characterized the infection and adequacy of the initial treatment, namely

– type of microorganism (Gram positive, Gram negative, fungi, other, - alone or in conjunction-, nonisolated microorganism),
– infection focus (urological, respiratory, neurological, intra-abdominal, other),
– positive blood cultures,
– antibiotic therapy (guideline concordant or not) defined as antibiotic therapy concordant with current guidelines of European societies for respiratory/urinary tract/intrabdominal/CNS/skin/other infections
– multi-drug resistant microorganisms (MDR) defined as a microorganism resistant to more then 2 different groups of antibiotics
– polymicrobial infection defined as an infection with more than one responsible micoorganism.
– Health care associated sepsis defined as infection/sepsis acquired before or within the first 48h after admission in patients with the any one of the following criteria: (1) hospitalization for two or more days in an acute care facility within 90 days of infection, (2) patients from a nursing home or longterm care facility, (3) patients who attended a hospital or hemodialysis clinic, and (4) those who received intravenous antibiotic therapy, chemotherapy, or wound care within 30 days of infection.
– For community-acquired sepsis: time from hospital admission until first administration of antibiotic.
– For health-care associated sepsis: time from recognition of severe sepsis/septic shock until first administration of antibiotic.
– For R component we considered variables that are potential indicators of response to the infection: the selected variables were
– C-reactive protein (CRP) (mg/dL) - one measurement per day, or the worst value per day during the first five days
– white cell count (WCC) (10 3 *L) and neutrophils (%) – one measurement per day or the worst measurement each day in the first five days
– central temperature – one measurement per day or the worst measurement each day in the first five days
– heart rate (bpm) – the worst measurement of each day (as in the SAPS II or APACHE II) during the first five days
– respiratory rate - one measurement per day or the worst measurement each day in the first five days
– sistolic or mean arterial pressure - one measurement per day or the worst measurement each day in the first five days
– For the O component the selected variables were those that reflect organ dysfunction namely
– glycemia (mg/dL) - hypoglycemia was defined as glycemia lower than 90 mg/dL and hyperglycemia was defined as higher than 150 mg/dL. The worst value ( the most far from the normal) of each day in the first five days
– serum lactate (mmol/L) the worst measurement ( the most far from normal) of each day during the first five days

– SOFA score – one measurement per day in the first five days
– Glasgow coma score (measured or estimated if patient sedated, i.e. the last GCS before sedation) - the worst measurement of each day during the first five days
Other variables:
- Type of admission as medical or nonmedical (includes elective surgery, emergency surgery, trauma)