Ventilator-associated pneumonia (VAP) is a serious infection that occurs in patients who have been on mechanical ventilation for more than 48 hours in the intensive care unit (ICU). Early and accurate diagnosis is critical to reduce complications and improve outcomes. This prospective observational study aims to evaluate the diagnostic and prognostic value of reticulated platelet fraction (RP%) in patients diagnosed with VAP. Blood samples will be taken as part of routine care, and RP% levels will be analyzed using a standard hematology analyzer. The study will investigate whether RP% can help identify VAP earlier and predict outcomes such as mortality and response to antibiotics.

Inclusion Criteria:

• Age 18 years or older
• Receiving mechanical ventilation for more than 48 hours
• Diagnosed with ventilator-associated pneumonia (VAP) according to clinical, radiologic, and laboratory criteria

Exclusion Criteria:

• Diagnosis of pneumonia upon ICU admission
• Pneumonia as the primary reason for initiation of mechanical ventilation
• Mechanical ventilation duration less than 48 hours
• Pregnant or breastfeeding patients
• Presence of chronic inflammatory conditions, hematologic disorders, malignancy, autoimmune disease, or immunosuppressive/chemotherapy/radiotherapy treatment within the past 4 weeks

Critically ill adult patients (aged 18 years and older) who are mechanically ventilated for more than 48 hours in the intensive care unit and diagnosed with ventilator-associated pneumonia (VAP).