Assessing the predictive value of serum phosphate for short-term mortality in acute-on-chronic liver failure patients: An observational study at a non-transplant tertiary care centre.

Abstract

The gradual clinical worsening of acute-on-chronic liver failure (ACLF) leads to a high 28-day mortality rate. There are several prognostication scores for predicting early mortality in ACLF. Serum phosphate, which is the main component of adenosine tri-phosphate (ATP) synthesis, is utilized for liver synthetic functions, leading to subnormal or decreased serum phosphate levels. Hence more than normal levels of serum phosphate can be used as a marker of decreased liver cell reserve. Hence, we aimed to compare serum phosphate levels with available prognostic scores to assess mortality among ACLF patients. 100 consecutive ACLF patients according to the Asia Pacific Association for Study of the Liver (APASL) definition were studied. The baseline blood workups and determination of viral bio-markers, serum phosphate, and lactate levels on days 1, 3, and 7 were carried out and prospectively followed up, and the baseline serum phosphate levels were compared with the usual scores to predict the 28-day mortality. CLIF-SOFA (accuracy 76-91%) followed by CLIF-C score (accuracy 73-84%) and AARC score (accuracy 70-85%) had the statistically significantly highest accuracy as compared with CTP, MELD, and MELD-Na on all three days. Serum phosphate values (accuracy 69-86%) on all three days were not better than the CLIF-SOFA score but better than all other prognostic scores on days 3 and 7. The high serum phosphate levels on day 3 with a value of more than 6.4 mg/dl showed almost comparable accuracy with CLIF-SOFA for screening short-term mortality. Hence serum phosphate measurement can be used as a simple bedside laboratory investigation to predict mortality in ACLF patients and early interventions in low-resource settings.