Abstract Exogenous lipoid pneumonia (ELP) is an uncommon pulmonary condition caused by aspiration or inhalation of lipid-containing substances, leading to intra-alveolar lipid accumulation, inflammation, and impaired gas exchange. Adult cases from chronic intranasal or perinasal use of petroleum-based or mentholated topical ointments are rare yet likely under-recognized. Because the radiologic appearance may mimic infection, pulmonary edema, or interstitial lung disease, diagnosis is often delayed. Early identification and discontinuation of exposure are essential for recovery. A 71-year-old woman with 35-pack-year smoking history, prior ST-elevation myocardial infarction, and chronic obstructive pulmonary disease presented with two months of progressive dyspnea and productive cough. She had been treated repeatedly as an outpatient for presumed COPD exacerbation and left-sided pneumonia with nebulized bronchodilators, low-dose methylprednisolone, and antibiotics, but her oxygen requirement worsened, prompting ICU transfer for noninvasive positive-pressure ventilation and later high-flow nasal cannula. Detailed history revealed nightly intranasal and perinasal application of petroleum-based and mentholated ointments for over a year, continued during hospitalization and used frequently in preceding months. Contrast-enhanced chest CT showed diffuse ground-glass opacities with interlobular septal thickening (“crazy-paving”), dense left-lower-lobe consolidation, mucus plugging, and right-middle-lobe atelectasis. Infectious and autoimmune evaluations were negative. Bronchoscopy with bronchoalveolar lavage was deferred owing to high-flow oxygen use and a do-not-intubate status. All lipid-containing products were discontinued. With clinical decline, corticosteroids were intensified: methylprednisolone was replaced with intravenous dexamethasone 10 mg daily, resulting in rapid improvement. She was transitioned to an oral prednisone taper, weaned to 2 L oxygen, and discharged with pulmonary follow-up. ELP in adults is classically linked to chronic aspiration or intranasal use of petroleum-based substances such as petrolatum, mineral oil, or mentholated ointments. Recently, additional phenotypes have emerged involving inhalation of lipid aerosols from e-cigarettes, cannabis oils, and essential-oil vaporizers, as well as iatrogenic paraffin or mineral-oil exposure. Presentations range from incidental findings to acute hypoxemic respiratory failure requiring intensive care. The “crazy-paving” CT pattern, though suggestive, overlaps with edema, alveolar proteinosis, organizing pneumonia, and hemorrhage, complicating diagnosis. Recognition of exposure history, prompt discontinuation of the lipid source, airway-clearance measures, and corticosteroid therapy are key to recovery and prevention of fibrosis. ELP should be considered in adults with unexplained hypoxemia and bilateral ground-glass or crazy-paving opacities when infectious and autoimmune causes are excluded. Careful history-taking to identify oil-based intranasal or inhalational exposures, coupled with timely corticosteroid therapy, can prevent progression to respiratory failure and underscores the need for diagnostic vigilance in atypical presentations. This abstract is funded by: None
Salik et al. (Fri,) studied this question.