Exogenous lipoid pneumonia. Clinical and radiological manifestations

Abstract

Lipoid pneumonia results from the pulmonary accumulation of endogenous or exogenous lipids. Host tissue reactions to the inhaled substances differ according to their chemical characteristics. Symptoms can vary significantly among individuals, ranging from asymptomatic to severe, life-threatening disease. Acute, sometimes fatal, cases can occur, but the disease is usually indolent. Possible complications include superinfection by nontuberculous mycobacteria, pulmonary fibrosis, respiratory insufficiency, cor pulmonale, and hypercalcemia. The radiological findings are nonspecific, and the disease presents with variable patterns and distribution. For this reason, lipoid pneumonia may mimic many other diseases. The diagnosis of exogenous lipoid pneumonia is based on a history of exposure to oil, characteristic radiological findings, and the presence of lipid-laden macrophages on sputum or BAL analysis. High-resolution computed tomography (HRCT) is the best imaging modality for the diagnosis of lipoid pneumonia. The most characteristic CT finding in LP is the presence of negative attenuation values within areas of consolidation. There are currently no studies in the literature that define the best therapeutic option. However, there is a consensus that the key measure is identifying and discontinuing exposure to the offending agent. Treatment in patients without clinical symptoms remains controversial, but in patients with diffuse pulmonary damage, aggressive therapies have been reported. They include whole lung lavage, systemic corticosteroids, and thoracoscopy with surgical debridement.

Lipoid Pneumonia for Two Cases

“…They appear in bronchial obstruction distal or from the walls of destroyed alveoli, in areas of chronic suppuration, or due to other kinds of diseases such as lipid storage disorder (1,5,6). Other reasons that facilitate exogenous lipoid pneumonia are: advanced age, mental health disorders, aphagia, anatomical and structural abnormalities of pharynx and larynx, gastroesophageal reflux, hiatal hernia, Zenker's diverticulum, achalasia and etc., as well as psychogenic disorders and neuromuscular diseases (5). Clinical lipoid pneumonia depends on the amount of aspirated substance, as well as the aspiration period.…”

“…Clinical lipoid pneumonia depends on the amount of aspirated substance, as well as the aspiration period. It may have sudden onset, due to an enormous amount of substance being aspirated or slow onset, due to the chronic aspiration of a substance in small quantities (1,5). Symptoms may appear instantly or hours after the aspiration.…”

“…Symptoms may appear instantly or hours after the aspiration. Symptoms may be mild but it is also possible to have substantial respiratory insufficiency that requires mechanic ventilation, consisting of symptoms like cough, dyspnea, chest pain, hemoptysis and fever (1,5,7,8). Both cases applied to emergency due to cough, difficulty in breathing, chest pain and fever.…”

“…It may be difficult to distinguish the disease from bacterial pneumonia, tuberculosis, and cystic fibrosis. Therefore, anamnesis is an important part of the diagnosis (1,5,8). Radiological findings may appear within 30 minutes of the aspiration or in the subsequent 24 hours (1,5).…”

“…Therefore, anamnesis is an important part of the diagnosis (1,5,8). Radiological findings may appear within 30 minutes of the aspiration or in the subsequent 24 hours (1,5). A chest x-ray may indicate diffusive or integrative consolidations, opacities with improper bilateral borders, lesions similar to irregular bulks, bilateral-symmetrical reticuloendothelial infiltration, alveolar-intersystol patterns, and unilateral or bilateral nodular lesions (1,3,5).…”