TY - JOUR
T1 - Presenting Clinicoradiologic Features, Causes, and Clinical Course of Exogenous Lipoid Pneumonia in Adults
AU - Samhouri, Bilal F.
AU - Tandon, Yasmeen K.
AU - Hartman, Thomas E.
AU - Harada, Yohei
AU - Sekiguchi, Hiroshi
AU - Yi, Eunhee S.
AU - Ryu, Jay H.
N1 - Funding Information:
Author contributions: J. H. R. takes responsibility for the accuracy of the manuscript's content, including the data described within, and its analysis and interpretation. B. F. S. Y. K. T. T. E. H. Y. H. H. S. and J. H. R. contributed substantially to the study design, data collection and interpretation, and writing of the manuscript. Financial/nonfinancial disclosures: None declared. Additional information: The e-Tables can be found in the Supplemental Materials section of the online article. FUNDING/SUPPORT: The authors have reported to CHEST that no funding was received for this study.
Publisher Copyright:
© 2021 American College of Chest Physicians
PY - 2021/8
Y1 - 2021/8
N2 - Background: Exogenous lipoid pneumonia (ELP) develops when lipid-containing substances enter the airways through aspiration or inhalation and incite an inflammatory response. The diagnosis of ELP often is difficult because findings may be nonspecific. The clinical course of ELP has not been well characterized. Research Question: What are the presenting clinicoradiologic features of ELP, its causative agents, and clinical course? Study Design and Methods: We searched the Mayo Clinic electronic medical records for patients diagnosed with ELP between 1998 and 2020. Inclusion diagnostic criteria were: (1) lipoid pneumonia (LP) on histopathologic examination, (2) lipid-laden macrophages in BAL fluid, or (3) fatty attenuation of parenchymal opacities on chest CT imaging. Additionally, all patients were required to have a clinician diagnosis of LP in the absence of conditions known to cause endogenous LP. Results: Thirty-four patients were identified. Mean age was 71 years, with no sex predominance; one-half were asymptomatic. The diagnosis was confirmed by lung biopsy (including three lobectomies for suspected malignancy) in 71% of patients, CT scan in 24% of patients, and BAL in 5% of patients. Most patients manifested bilateral parenchymal opacities that commonly involved the lower lobes; fatty attenuation was identifiable in only 41% of patients. A causative substance was identified in 79% of patients, in most cases after the diagnosis was established. Over a median follow-up of 1.2 years, only 20% of patients with chronic respiratory symptoms improved, whereas 50% worsened. Over a median follow-up interval of 1 year, CT scan abnormalities improved or resolved in 33% of patients and progressed in 39% of patients. Patients who deteriorated were older, with a higher prevalence of GI disorders than those who remained stable or improved. Interpretation: ELP often is asymptomatic and may not manifest fatty attenuation on chest CT imaging. Clinical and radiologic abnormalities persist or worsen in most affected patients, even when the causative agent is discontinued.
AB - Background: Exogenous lipoid pneumonia (ELP) develops when lipid-containing substances enter the airways through aspiration or inhalation and incite an inflammatory response. The diagnosis of ELP often is difficult because findings may be nonspecific. The clinical course of ELP has not been well characterized. Research Question: What are the presenting clinicoradiologic features of ELP, its causative agents, and clinical course? Study Design and Methods: We searched the Mayo Clinic electronic medical records for patients diagnosed with ELP between 1998 and 2020. Inclusion diagnostic criteria were: (1) lipoid pneumonia (LP) on histopathologic examination, (2) lipid-laden macrophages in BAL fluid, or (3) fatty attenuation of parenchymal opacities on chest CT imaging. Additionally, all patients were required to have a clinician diagnosis of LP in the absence of conditions known to cause endogenous LP. Results: Thirty-four patients were identified. Mean age was 71 years, with no sex predominance; one-half were asymptomatic. The diagnosis was confirmed by lung biopsy (including three lobectomies for suspected malignancy) in 71% of patients, CT scan in 24% of patients, and BAL in 5% of patients. Most patients manifested bilateral parenchymal opacities that commonly involved the lower lobes; fatty attenuation was identifiable in only 41% of patients. A causative substance was identified in 79% of patients, in most cases after the diagnosis was established. Over a median follow-up of 1.2 years, only 20% of patients with chronic respiratory symptoms improved, whereas 50% worsened. Over a median follow-up interval of 1 year, CT scan abnormalities improved or resolved in 33% of patients and progressed in 39% of patients. Patients who deteriorated were older, with a higher prevalence of GI disorders than those who remained stable or improved. Interpretation: ELP often is asymptomatic and may not manifest fatty attenuation on chest CT imaging. Clinical and radiologic abnormalities persist or worsen in most affected patients, even when the causative agent is discontinued.
KW - aspiration-related syndromes
KW - clinical course
KW - exogenous lipoid pneumonia
KW - fatty attenuation
KW - radiologic evolution
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U2 - 10.1016/j.chest.2021.02.037
DO - 10.1016/j.chest.2021.02.037
M3 - Article
C2 - 33647249
AN - SCOPUS:85108603405
SN - 0012-3692
VL - 160
SP - 624
EP - 632
JO - Chest
JF - Chest
IS - 2
ER -