The use of the neutrophil-derived Heparin-binding protein (HBP) as a biomarker for pneumonia was investigated in this exploratory case-control study in two intensive care units at a tertiary referral hospital.<h4>Methods</h4>Patients with clinical signs of pneumonia were recruited and bronchoalveolar lavage fluid (BALF) or bronchial wash (BW) samples were collected. Here, AZU1 is linked to pneumonia.