Blood Cell Count Derived Inflammatory Indexes in Acute Exacerbation of Idiopathic Pulmonary Fibrosis

Overview

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by progressive scarring. Sometimes, patients experience a sudden and severe worsening of their symptoms, known as an acute exacerbation (AE-IPF), which carries a high risk of mortality. Currently, doctors lack reliable bedside tools at the time of hospital admission to predict which patients will improve with standard care and which will require early escalation of treatment. This prospective observational study aims to determine if simple, widely available blood tests can be used as biomarkers to predict patient outcomes during an acute exacerbation. Researchers will focus on complete blood count (CBC)-derived inflammatory indexes, which are calculated ratios of different types of blood cells (such as the neutrophil-to-lymphocyte ratio). Participants hospitalized with AE-IPF will have their blood cell counts and oxygen levels (PaO2/FiO2 ratio) monitored on days 0 (admission), 3, 7, and 14. The study will evaluate the correlation between the change in these inflammatory indexes and the change in oxygen levels over the first week of hospitalization. Additionally, it will assess how accurately the admission blood test values, compared to the changes seen by day 3, can predict in-hospital clinical deterioration (such as the need for a ventilator, transfer to the intensive care unit, or death). The aim is to find out if tracking changes in these simple blood test indexes can provide clinicians with a cost-effective, early-warning tool to guide treatment decisions for patients suffering from AE-IPF.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrosing interstitial pneumonia of unknown cause carrying a median survival of approximately three years from diagnosis. While most patients experience gradual functional deterioration, a substantial subset suffers acute exacerbations (AE-IPF) characterized by rapid worsening of dyspnea, new bilateral ground-glass opacities or consolidation on imaging, and severe hypoxemia. AE-IPF carries an in-hospital mortality of 50% or higher, and clinicians currently lack reliable bedside tools to predict which patients will improve with conservative therapy and who will require early escalation. The complete blood count (CBC) is a widely available and inexpensive laboratory test. Mathematically derived ratios and composite indices (such as the neutrophil-to-lymphocyte ratio \[NLR\], monocyte-to-lymphocyte ratio \[MLR\], platelet-to-lymphocyte ratio \[PLR\], and systemic immune-inflammation index \[SII\]) reflect the balance of innate and adaptive immunity and have been associated with adverse outcomes across various inflammatory and neoplastic conditions. However, most CBC-index work in IPF has examined stable-state prognostication or static admission values. This study addresses a substantive gap in the literature by systematically characterizing the dynamic behavior of these indices in response to AE-IPF treatment, utilizing head-to-head paired comparisons of baseline versus on-treatment change values. This prospective, single-centre observational cohort study will be conducted at Assiut University Hospitals. Enrolled patients will undergo a full medical and clinical history, clinical examination, and a high-resolution computed tomography (HRCT) review to re-confirm the underlying usual interstitial pneumonia (UIP) pattern. Key assessments include: * CBC Monitoring: Assessed at days 0, 3, 7, and 14 (if hospitalized) to track absolute cell counts and calculate derived inflammatory indices (NLR, MLR, PLR, SII, SIRI, AISI, and PIV). * Arterial Blood Gas (ABG): Assessed on stable FiO2 to track the PaO2/FiO2 ratio from day 0 to day 7. * GAP Index: Calculated using the most recent stable-state pulmonary function values (incorporating gender, age, and physiology) whenever possible. * Clinical Monitoring:Treatment exposures (steroids, antibiotics, antifibrotics), adverse events, and escalations to ventilatory support will be recorded.