Exogenous Lipoid Pneumonia in Laryngectomy Patients: Radiological Findings

Exogenous Lipoid Pneumonia due to Chronic Inhalation of Oily Product Used as a Lubricant of Tracheotomy Cannula

Exogenous lipoid pneumonia (ELP) is caused by the inhalation of vaporized oily products. Long-term exposure can result in chronic disease, whereas acute form usually results from massive aspiration of fatty substances. It has an incidence of 1.0%-2.5%. In case of symptomatic patients, the clinical presentation mainly includes acute or chronic respiratory symptoms such as dyspnea, fever, cough and less frequently chest pain, hemoptysis, or weight loss. Radiological findings are often aspecific or misinterpreted, and ELP is sometimes misdiagnosed as a malignancy of the lungs. Patient history and radiological findings can lead to a suspicion of ELP, but histological microscopic findings of intra-alveolar lipid and lipid-laden macrophages are required to confirm the diagnosis The mainstay of treatment consists of avoiding ongoing exposure and providing supportive care as repeated whole-lung lavage, corticosteroids, and/or immunoglobulins. Surgery is reserved for cases of high suspicion of cancer or serious clinical impact (as recurrent infections). Prognosis is benign, even if it has been reported cases of progression to severe respiratory failure, cor pulmonale, superinfection, and association with lung cancer. Here, we describe a case of ELP due to chronic inhalation of oily product (Vaseline) used as a lubricant of tracheotomy cannula.

False positive 18FDG PET-CT results due to exogenous lipoid pneumonia secondary to oily drug inhalation: A case report

RATIONALE

Exogenous lipoid pneumonia is a rare condition due to abnormal presence of oily substances in the lungs. It is a rarely known cause for false positive FDG PET-CT results and can sometimes lead to invasive investigations. Searching and finding the source of the oily substance is one of the keys to the diagnosis. Inhalation of oily drugs during snorting has rarely been described.

PATIENT CONCERNS

A patient with well controlled HIV infection was referred for an FDG PET-CT to assess extension of Kaposi's disease, recently removed from his right foot. The patient had no particular symptoms.

DIAGNOSES

Abnormal uptake of FDG was found in a suspicious lung nodule. An experienced radiologist thought the nodule was due to lipoid pneumonia.

INTERVENTIONS

Bronchoalveolar lavage fluid did not contain lipid-laden macrophages but bronchoscopy showed violet lesions resembling Kaposi's disease lesions. Lobectomy was performed after a multidisciplinary discussion.

OUTCOMES

Anatomopathological analysis revealed the nodule was due to lipoid pneumonia. The patient's quality of life did not diminish after the operation and he is still in good health. The source of the oily substance causing lipoid pneumonia was found after the surgery: the patient used to snort oily drugs.

LESSONS

The presence of a suspicious lung nodule possibly due to lipoid pneumonia in a patient with known Kaposi's disease was difficult to untangle and lead to invasive surgery. It is possible that if a source of exogenous lipoid pneumonia had been found beforehand, surgery could have been prevented.

Teppanyaki/Hibachi Pneumonitis: An Exotic Cause of Exogenous Lipoid Pneumonia

Exogenous lipoid pneumonia (ELP) is a rare type of inflammatory lung disease caused by aspiration and/or inhalation of fatty substances and characterized by a chronic foreign body-type reaction to intra-alveolar lipid deposits. The usual clinical presentation occurs with insidious onset of nonspecific respiratory symptoms and radiographic findings that can mimic other pulmonary diseases. Diagnosis of ELP is often missed or delayed as it requires a high index of suspicion and familiarity with the constellation of appropriate history and radiologic and pathologic features. We herein report a case of occupational exposure to tabletop "Teppanyaki" entertainment cooking as a cause of ELP, confirmed by surgical lung biopsies in a 63-year-old Asian woman who worked as a Hibachi-Teppanyaki chef for 25 years.

Investigation of rare chronic lipoid pneumonia associated with occupational exposure to paraffin aerosol

Objectives:

Occupational exposure to paraffin is an infrequent cause of lipoid pneumonia (LP) and related data are scare. We investigated the possible relationship between three rare cases of chronic LP and occupational exposure to paraffin aerosol in an iron foundry.

Methods:

The three cases of LP and their workplaces were investigated using data from field investigations, air monitoring, pulmonary radiological examinations, cell staining, and lung biopsies.

Results:

The patients had long-term occupational exposure to paraffin. X-ray diffraction testing revealed that the raw material from the workshop was paraffin crystal. The air concentrations of paraffin aerosol in workplaces were significantly higher than outdoor background levels. Small diffuse and miliary shadows with unclear edges were observed throughout the whole lungs via radiography. Computed tomography revealed diffuse punctate nodules and a high density of stripe-like shadows in both lungs (ground-glass opacity in a lower lobe, and a mass-like lesion and high translucent area near the bottom of the lung). Lipid-laden macrophages were found in the sputum and bronchial lavage. A broadened alveolar septum and local focal fibrosis were also discovered via lung biopsy. The inflammatory reaction in the lung tissues appeared to resolve over time.

Conclusions:

These three rare cases of chronic LP in workers during molding and repair processes were associated with occupational paraffin aerosol exposure. Therefore, primary prevention is essential for molding or repairing workers in the iron foundry, and a differential diagnosis of occupational chronic LP (vs. pneumoconiosis) should be considered when treating these workers.