{
  "abstract": "Background and aims Inflammation may play a role in driving interstitial lung diseases (ILD). Radiological ground-glass opacity (GGO) may not reliably distinguish fine intralobular fibrosis from inflammatory processes in fibrotic ILD. We therefore investigated the relationship between GGO, fibrosis and leukocytes in bronchoalveolar lavage (BAL).Methods We recruited patients with fibrotic ILD at a single centre between May 2014 and February 2018. The extent of GGO and fibrosis was evaluated by two radiologists. Linear regression examined the association between leucocyte numbers in BAL obtained from the right middle lobe and GGO/fibrosis extent in whole lung, adjusting for age, sex and smoking. A Z-test was used to compare the association between BAL and GGO/fibrosis.Results 316 patients were included. Adjusting analyses for covariates, only BAL eosinophil and eosinophil-to-macrophage ratio were positively associated with GGO involvement (0.23 (95% CI 0.03 to 0.42) p=0.023 and 11.21 (95% CI 1.33 to 21.08) p=0.026). Lymphocyte percentages (fibrosis −0.17 vs GGO −0.02 p=0.046); neutrophil percentages (fibrosis 0.38 vs GGO 0.06 p=0.002); neutrophil-to-lymphocyte ratio (fibrosis 0.63 vs GGO −0.05 p=0.027); neutrophil-to-macrophage ratio (fibrosis 14.08 vs GGO 2.57 p=0.015) and neutrophilia (fibrosis 6.81 vs GGO −0.31 p=0.002) all demonstrated a significantly stronger association with fibrosis than GGO.Conclusions Lack of relationships between radiological GGO and BAL leucocyte counts in fibrotic lung disease indicates that GGO may not always be inflammatory in nature. Higher levels of neutrophils were associated with more extensive fibrosis.",
  "authors": [
    {
      "affiliations": [
        "Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, UK",
        "Respiratory and Respiratory Critical Care Unit, Division of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Hat Yai, Thailand",
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Punchalee Kaenmuang"
    },
    {
      "affiliations": [
        "Department of Radiology, Royal Free Hospital, London, UK"
      ],
      "name": "Joseph L Barnett"
    },
    {
      "affiliations": [
        "Keck School of Medicine, University of Southern California, Los Angeles, California, USA",
        "National Heart and Lung Institute, Imperial College London, London, UK"
      ],
      "name": "Toby M Maher"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London, London, UK"
      ],
      "name": "Jennifer K Quint"
    },
    {
      "affiliations": [
        "School of Public Health, Imperial College London, London, UK"
      ],
      "name": "Alexander Adamson"
    },
    {
      "affiliations": [
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK",
        "National Heart and Lung Institute, Imperial College London, London, UK"
      ],
      "name": "Zhe Wu"
    },
    {
      "affiliations": [
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK",
        "National Heart and Lung Institute, Imperial College London, London, UK"
      ],
      "name": "David J F Smith"
    },
    {
      "affiliations": [
        "Department of Radiology, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Bhavin Rawal"
    },
    {
      "affiliations": [
        "Department of Radiology, University College Hospital, London, UK"
      ],
      "name": "Arjun Nair"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London, London, UK"
      ],
      "name": "Simon L F Walsh"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London, London, UK",
        "Department of Radiology, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Sujal R Desai"
    },
    {
      "affiliations": [
        "Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, UK",
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Peter M George"
    },
    {
      "affiliations": [
        "Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, UK",
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Maria Kokosi"
    },
    {
      "affiliations": [
        "Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, UK",
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Vasilis Kouranos"
    },
    {
      "affiliations": [
        "Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, UK",
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Elisabetta A Renzoni"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London, London, UK",
        "Department of Histopathology, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Alexandra Rice"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London, London, UK",
        "Department of Histopathology, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Andrew G Nicholson"
    },
    {
      "affiliations": [
        "Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, UK",
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Felix Chua"
    },
    {
      "affiliations": [
        "Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, UK",
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Athol U Wells"
    },
    {
      "affiliations": [
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK",
        "National Heart and Lung Institute, Imperial College London, London, UK"
      ],
      "name": "Philip L Molyneaux"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London, London, UK",
        "Department of Radiology, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "Anand Devaraj"
    },
    {
      "affiliations": [
        "Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, UK",
        "Interstitial Lung Disease Unit, Royal Brompton Hospital, Guy’s and St Thomas’ National Health Service Foundation Trust, London, UK"
      ],
      "name": "R Gisli Jenkins"
    },
    {
      "affiliations": [
        "Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, UK",
        "National Institute for Health Research Biomedical Research Centre, Respiratory Research Unit, University of Nottingham, Nottingham, UK"
      ],
      "name": "Iain D Stewart"
    }
  ],
  "title": "Association of bronchoalveolar lavage cellular analysis and radiological findings in fibrotic interstitial lung diseases",
  "uid": "a86903a4-e386-5600-bae0-175ce0338e81"
}