Abstract

Background: Calprotectin is found extensively in the cytoplasm of neutrophils and it is released predominately in inflammatory processes. Calprotectin is released locally which suggests that it is a sensitive indicator of inflammation. Bronchiolitis Obliterans (BO) describes a pathologic alteration of small airways which begins with an initial injury and is followed by a distinctive inflammatory response. Aims: The aim of this study is to investigate for the first time to what extent calprotectin is increased in sputum of BO patients and whether it can be used as inflammatory marker. Methods: 28 patients with BO median age 14.2 years (6.2-27.3) and 18 healthy controls median age 16.2 years (7.6-25.0) were investigated by bodyplethysmography, lung clearance index (LCI) and induced sputum. Cell counts, cytokines IL-1β, IL-6 and IL-8 were measured by cytometric bead array and sputum calprotectin by commercial ELISA. Results: Patients with BO revealed compromised lung function: FVC, FEV1, MEF25 were decreased while RV/TLC and LCI were significantly increased (12.1 BO vs. 7.1 controls). Sputum of BO patients showed significantly increased neutrophils, IL-8 and calprotectin (Calprotectin:median 6428.5; 30.6-84000ng/ml vs. controls:median 949.6; 135.0-2886.4ng/ml). There was a significant correlation between calprotectin and IL-8 (rho=0,871; p Conclusion: Calprotectin is significantly increased in BO which emphasizes the ongoing neutrophilic inflammatory process. Further investigations are required to show whether calprotectin is a sensible surrogate marker to support the diagnosis of BO and monitoring of anti-inflammatory therapy

Highlights

  • Bronchiolitis obliterans (BO) is a chronic disease in which persistent inflammation leads to obstruction and obliteration of the small airways

  • The forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and the maximum expiratory flow rate at 25% vital capacity (MEF25) were significantly decreased, while reserve volume (RV)/TLC and lung clearance index (LCI) were significantly increased in BO patients (BO: 12.1, 7.3-20.5; controls: 7.1, 6.0-8.4, p < 0:001) compared to controls (Table 1)

  • No airway reversibility was detected in the majority of BO patients (Figure 1)

Read more

Summary

Introduction

Bronchiolitis obliterans (BO) is a chronic disease in which persistent inflammation leads to obstruction and obliteration of the small airways. Calprotectin is significantly elevated in the sputum of BO patients and reflects ongoing neutrophilic inflammation. The initial severe insult is thought to affect the lower airways and can be caused by either a pathogen, postinfectious BO (PIBO), lung transplantation (LT) or bone marrow transplantation (BMT), or BO syndrome (BOS) [3,4,5]. This failure of resolution of initial and ongoing inflammation is likely to be an important part of the disease process of BO. In combination with the proliferation of granulation tissue in the small airways, this leads to obstruction of the bronchioli with air trapping and hyperinflation [1, 2, 6]

Objectives
Methods
Results
Conclusion
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call