Microalbuminuria evaluated as a biomarker in patients with septic shock

Introduction

The level of microalbuminuria is thought to reflect the severity of inflammation during acute phase response and may have prognostic value with regard to survival. This study aimed to describe urinary albumin excretion in patients with septic shock and changes in microalbuminuria levels in the first 3 days of treatment.

Methods

Prospective observational study of 49 consecutive patients with septic shock admitted to a general ICU. During the first 24 hours after severe sepsis was diagnosed, we collected data to calculate APACHE II and SOFA scores and urinary sample to measure urinary albumin. Another sample of urine was collected on the third day of septic shock. Microalbuminuria was measured by immunoturbidimetry with a limit of detection of 3.5 mg/l. The study was approved by the local Ethic Committee.

Results

The mean age was 65.8 ± 15 years and male sex was more frequent (63.3%). Pneumonia (59.2%) was the most common source of sepsis. Mean APACHE II and SOFA scores on the first day of sepsis were 24.4 ± 7.7 and 8.7 ± 3.7, respectively. Observed mortality was 71.4%. Median urinary albumin was 7.0 mg/l (IQT: 4.7 to 60.3 mg/l) for survivors and 15.5 mg/l (IQT: 7.9 to 77.1 mg/l) for nonsurvivors on the first day of septic shock. Urinary albumin decreased from 7.0 mg/l (IQT: 4.7 to 60.3 mg/l) to 3.9 mg/l (IQT: 3.6 to 44.1 mg/l) in survivors during the first 3 days of septic shock, and in nonsurvivors remained at the same level from 15.5 mg/l (IQT: 7.9 to 77.1 mg/l) to 14.5 mg/l (IQT: 3.9 to 45.3 mg/l) in the period of observation.

Conclusions

Patients with septic shock showed high frequency of microalbuminuria. Levels of urinary albumin showed a tendency to decrease in survivors, suggesting prognostic significance.