The Influence of Characteristics and Indexes (NLR, PNI, and SII) Evaluated at Admission on the Mortality Prediction...

Infective endocarditis (IE) is a serious and potentially life-threatening infection with high morbidity and mortality. Early risk identification is critical for enabling timely treatment and preventing adverse outcomes. Recently, several low-cost and accessible inflammatory markers, such as the neutrophil-to-lymphocyte ratio (NLR), prognostic nutritional index (PNI), and systemic immune-inflammation index (SII), have gained attention for their potential prognostic value in infectious diseases.

This retrospective study evaluated patients diagnosed with definite IE between May 2014 and May 2024 at Bakırköy Dr. Sadi Konuk Training and Research Hospital. Clinical characteristics, laboratory parameters, complications, and outcomes were compared between survivors and non-survivors. The predictive value of NLR, PNI, and SII for in-hospital mortality was assessed.

A total of 78 patients with IE were included, with an overall mortality rate of 52.5%. Non-survivors were significantly older (p = 0.001) and had higher rates of cardiac complications (p < 0.05). PNI values were significantly lower in non-survivors (p = 0.014). Undergoing cardiac surgery was associated with a lower mortality rate (p = 0.024).

PNI, a simple, inexpensive, and readily available marker, may provide valuable prognostic information in patients with infective endocarditis. This index could help in early risk stratification and clinical decision.