Intensive immunosuppressive therapy for endogenous lipoid pneumonia associated with rheumatoid arthritis

Abstract

Endogenous lipoid pneumonia is an uncommon inflammatory pulmonary disease that is caused by lipids from an endogenous source, the treatment for which has not been established. We report the first case of endogenous lipoid pneumonia presenting as lung consolidation and which was associated with rheumatoid arthritis. Treatment was successful with intensive immunosuppressive therapy. When a physician finds lung consolidation in a patient with active rheumatic disease, lipoid pneumonia should be considered.     

Acute lipoid pneumonia caused by accidental aspiration of vaseline used in nasogastric intubation

Exogenous lipoid pneumonia is a rare disease which is often underdiagnosed. Exogenous lipoid pneumonia has traditionally been considered a chronic process secondary to continued aspiration or inhalation of fatty substances. In its acute form exogenous lipoid pneumonia sometimes coincides with accidental massive aspiration of lipidic material, as has been traditionally described for fire eaters. We review the literature and report a case of acute lipoid pneumonia secondary to accidental aspiration of vaseline used to place a nasogastric tube, which had been inserted for gastric lavage after a suicide attempt by flurazepam ingestion.     

Exogenous lipoid pneumonia. Clinical and radiological manifestations

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.     

Radiological and clinical findings in acute and chronic exogenous lipoid pneumonia

PURPOSE: To describe the radiologic and clinical findings in a group of patients with exogenous lipoid pneumonia focusing on features that differentiate the acute and chronic presentations. MATERIALS AND METHODS: We retrospectively identified 15 patients from a single institution with exogenous lipoid pneumonia 1992-2001. Inclusion criteria were: imaging with chest CT and either CT features diagnostic of lipoid pneumonia or intrapulmonary lipids on pathologic examination. Each chart was reviewed for the clinical presentation, history of ingestion/exposure, predisposing factors, treatment and response to therapy. Initial (n = 13) and follow-up (n = 11) chest radiographs were reviewed for the patterns and distribution of lung parenchymal abnormalities and pleural effusion. Initial (n = 15) and follow-up (n = 7) CT scans were reviewed for lung parenchymal abnormalities (consolidation, ground glass opacities, linear/nodular opacities, masses, and crazy paving), presence or absence of fat attenuation, and pleural effusion. The groups were compared using the Fischer exact test. RESULTS: Nine patients had acute lipoid pneumonia, 7 males and 2 females with a mean age of 45 (range 4.5-81) years. Six patients had chronic lipoid pneumonia, 4 men and 2 women with a mean age of 63 (range 37-83) years. 78% (7/9) of patients with acute and all of the patients with chronic presentations had a known ingestion and/or a predisposing condition associated with lipoid pneumonia. On chest radiographs, consolidation and lower lobe involvement were present in the majority of patients with acute and none of the patients with chronic presentations. On CT, consolidation and fat attenuation were present in the majority of patients with each presentation. However, masses were present in 67% (4/6) of patients with chronic and none of the patients with acute presentation (P < 0.05). 86% (6/7) of patients with acute presentation had improvement on follow-up chest radiograph in contrast to none of the patients with chronic presentation (P < 0.05). 75% (3/4) of patients with acute lipoid pneumonia had improvement on follow-up CT in contrast with 67% (2/3) of patients with chronic lipoid pneumonia who had progression on follow-up CT. CONCLUSIONS: The imaging features of acute and chronic lipoid pneumonia overlap with consolidation and lower lobe involvement present in both groups. However, only the patients with acute lipoid pneumonia had pleural effusions and improvement on follow-up. Only the patients with chronic lipoid pneumonia had pulmonary masses.     

Exogenous lipoid pneumonia induced by aspiration of insecticide

Exogenous lipoid pneumonia is a rare disorder caused by inhalation and/or aspiration of oil-based substances. The confirmed diagnosis of exogenous lipoid pneumonia is difficult, especially in cases for which it is impossible to ascertain a history of inhalation or aspiration. We present a case of exogenous lipoid pneumonia due to aspiration of insecticide, for which the computed tomography findings of fat attenuation within the lesion were helpful in reaching a correct diagnosis.     

Lipoid pneumonia: a challenging diagnosis

Lipoid pneumonia is a rare medical condition, and is usually classified into two groups, ie, exogenous or endogenous, depending on the source of lipids found in the lungs. Exogenous lipoid pneumonia may result from the aspiration of food and lipids. Although most cases are asymptomatic, common symptoms include cough, dyspnea, chest pain, pleural effusions, fever, and hemoptysis. Radiologically, lipoid pneumonia can manifest as consolidations, pulmonary nodules, or soft-tissue densities. These presentations involve a wide differential diagnosis, including lung cancer. Other rare causes of fatty pulmonary lesions include hamartomas, lipomas, and liposarcomas. The avoidance of further exposures and the use of corticosteroids, antibiotics, and lavage comprise the mainstays of treatment. The exclusion of mycobacterial infections is important during diagnosis, in view of their known association. Generally, acute presentations run a benign course, if promptly treated. Chronic cases are more persistent and difficult to treat. Although the radiologic and pathologic diagnosis is fairly reliable, more research is needed to clarify the optimal treatment and expected outcomes. We report on a 54-year-old man presenting with progressively worsening cough, hemoptysis, and dyspnea over a few weeks. The patient underwent multiple computed tomographies of the chest and bronchoscopies. All failed to diagnose lipoid pneumonia. The diagnosis was finally established using video-assisted thoracoscopic surgery. Most of the paraffinoma was resected during this surgery. He was treated with antibiotics and steroids, and discharged from the hospital in stable condition.     

Exogenous lipoid pneumonia. Presentation of a new case

Exogenous lipoid pneumonia is a rare disease, secondary to continued aspiration of exogenous lipoid. Usually is a chronic disease, but also an acute form can be produced by massive accidental aspirations of lipidic material. We present a case of chronic lipoid pneumonia secondary to the continued aspiration of "nasal drops ".     

Radiographic bilateral cavitary lesions in lipoid pneumonia

We report a case of lipoid pneumonia with pulmonary bilateral cavitated lesions. The diagnosis was based on the finding of abundant lipid-laden alveolar macrophages in bronchoalveolar lavage and the presence of histologic changes indicative of lipoid pneumonia in transbronchial lung biopsy.     

Positron emission tomography-positive squalene-induced lipoid pneumonia confirmed by gas chromatography-mass spectrometry of bronchoalveolar lavage fluid

Squalene is a type of oil obtained from shark liver. We describe a 76-year-old man diagnosed with chronic exogenous lipoid pneumonia due to squalene. A chest CT scan revealed pulmonary consolidation with ground-glass opacities in the right upper lobe. Positron emission tomography (PET) revealed significant uptake of 2-deoxy-2-F-fluoro-d-glucose (FDG) and 3'-deoxy-3'-F-fluorothymidine (FLT). Bronchoalveolar lavage (BAL) fluid contained many lipid-laden macrophages, and a transbronchial lung biopsy specimen showed clusters of foamy macrophages in alveolar spaces and granulomatous lesions. In addition, the presence of squalene in the BAL fluid was confirmed by gas chromatography-mass spectrometry, leading to a diagnosis of squalene-induced lipoid pneumonia. To the best of our knowledge, this is the first report of squalene-induced lipoid pneumonia in which squalene itself was successfully detected. This case also suggests the possibility that lipoid pneumonia shows significant uptake in FDG-PET and FLT-PET.     

A case of exogenous lipoid pneumonia diagnosed by transbronchial lung cryobiopsy

A 57-year-old man visited a referral physician due to abnormal chest shadows. Transbronchial lung biopsy (TBLB) failed to diagnose his condition. As antibiotics and systemic steroids did not improve the condition, he was referred to our hospital. A second TBLB in our hospital also failed to diagnose the disease. Transbronchial lung cryobiopsy (TBLC) was performed using radial endobronchial ultrasound with guide sheath (EBUS-GS), and the patient was diagnosed with lipoid pneumonia. Right upper lobe resection was performed, and lipoid pneumonia was confirmed from the surgical specimen. We report a case of lipoid pneumonia diagnosed by EBUS-GS TBLC.     

Incidence of lipoid pneumonia in a survey of 389 chronically ill patients

A survey of 389 chronically ill patients revealed fifty-seven cases (14.6 per cent) of lipoid pneumonia diagnosed by examination of the sputum, aspiration from the lung and roentgenographic studies of the chest. In fifty-five of the patients examined the sputum showed lipophages or abundant amounts of free lipoid material characteristic of lipoid pneumonia. Aspiration from the lung also revealed typical lipoidcontaining macrophages. Twenty patients showed characteristic roentgenographic manifestations of lipoid pneumonia. Thirteen revealed retrocardiac changes in lateral, oblique and when indicated, overexposed film studies which were considered to be consistent with oil aspiration pneumonia although the postero-anterior films were negative for such lesions.A significant number of the patients had a productive cough and positive physical signs most frequently found over the base of the right lower lobe.Examination of the sputum and, when necessary, of material aspirated from the lung are valuable procedures for making the diagnosis of lipoid pneumonia.The mechanism of the progressive nature of the disease after discontinuance of the incitant oily factors is suggested as due to reaspiration of disintegrated lipophages.     

Exogenous lipoid pneumonia induced by inhalation of insecticide]

We report a case of exogenous lipoid pneumonia induced by insecticide. A 67-year-old man was admitted to our hospital with complaints of dyspnea cough, hemoptysis, and shivering 6 hours after inhaling an insecticide. A chest radiograph on admission disclosed consolidation in the right upper lobe. Chest computed tomography showed nodular infiltrates associated with ground-glass opacities. Bronchoalveolar lavage fluid was hemorrhagic and showed neutrophilia. Pathological examination of transbronchial lung biopsy specimens showed numerous vacuolated macrophages in alveolar spaces. Electron microscopy demonstrated lipid droplets in the cytoplasm of these macrophages. These findings together yielded a diagnosis of exogenous lipoid pneumonia induced by insecticide. In addition, we experimentally induced a similar form of lipoid pneumonia in rats by intratracheal instillation of the same insecticide.     

Endogenous lipoid pneumonia preceding diagnosis of pulmonary alveolar proteinosis

Pulmonary alveolar proteinosis (PAP) is an under‐reported and under‐diagnosed condition, with a high percentage of cases found on autopsy or late stage disease. The etiology of PAP includes genetic, primary (anti‐granulocyte‐macrophage colony‐stimulating factor antibodies) and secondary (oncologic, rheumatologic, infectious, chemical and immunologic) causes. Here, we present the first reported pediatric case of endogenous lipoid pneumonia and non‐specific interstitial pneumonitis preceding the development of PAP.     

Lipoid pneumonia: a preventable form of drug-induced lung injury

We report a case where recurrent "pneumonia" was eventually diagnosed as lipoid pneumonia in an elderly patient with cerebrovascular disease. The discontinuation of paraffin oil laxative led to clinical improvement. Lipoid pneumonia, a foreign body-type reaction to the presence of lipid within lung parenchyma, is probably underdiagnosed and underreported, and paraffin oil laxative is the main causative agent. Paraffin oil is marketed as a food additive, and no information about its hazards is provided to clinicians or patients. We suggest that a change in paraffin oil licensing may decrease the incidence of lipoid pneumonia.     

Unilateral lung infiltrate. Lipoid pneumonia

A case of unilateral lipoid pneumonia, proven by alveolar lavage and transbronchial lung biopsy, is presented. Following a stroke, which resulted in difficulty in swallowing, the patient slept only on his right side accounting for the unilateral lung infiltrate. He had been taking mineral oil for several years accounting for the lipoid pneumonia.     

Fire eater's risk: lipoid pneumonia following aspiration of a liquid hydrocarbon mixture

Acute aspiration of a liquid hydrocarbon mixture by fire eaters may cause severe lipoid pneumonia. The toxic effect of ingested hydrocarbon chains depends on their length and biophysical qualities. We report the case of a patient who accidentally aspirated a hydrocarbon liquid resulting in a lipoid pneumonia. The pathomechanism, diagnostic work-up, and the therapeutic approach are discussed.     

Olive oil aspiration pneumonia (lipoid) in children

Summary In the Asir region of south-western Saudi Arabia, nasal instillation of olive oil to infants and children in the recumbent position is practised to relieve nasal congestion. Aspiration of olive oil results in lipoid pneumonia resistant to antimicrobial treatment. A series of 5 children, aged 4–72 months, with olive oil-induced lipoid pneumonia is presented. Clinical presentation included persistent coughing, tachypnoea, recurrent febrile illness and chest infections. The pulmonary radiological picture was mainly right middle lobar and perihilar infiltrates. Bronchial lavage and microscopic examination of the aspirate confirmed the presence of fat globules. The pneumonia resolved on treatment with steroids and physiotherapy in the form of clappings and vibrations. For infants and children in this area who present with persistent pulmonary infiltrates which are not responsive to antimicrobials, the differential diagnosis of not only animal fat (ghee, clarified butter) but also of olive oil lipoid pneumonia must be considered.     

Acute exogenous lipoid pneumonia caused by accidental kerosene ingestion in an elderly patient with dementia: A case report

Acute exogenous lipoid pneumonia is an uncommon condition caused by aspiration of oil‐based substances, occurring mainly in children. Here, we report the case of an 83‐year‐old patient with Alzheimer's disease who presented with coughing and hypoxia. The diagnosis of acute exogenous lipoid pneumonia caused by accidental kerosene ingestion was made on the basis of the patient's clinical history, and typical radiological and cytological findings. The patient's cognitive impairment and an unsafe environment, in which the patient's 91‐year‐old husband stored kerosene in an old shochu bottle, were responsible for the accidental ingestion. Acute exogenous lipoid pneumonia should be considered in the differential diagnosis for acute respiratory disorders in the rapidly aging population. Geriatr Gerontol Int 2013; 13: 222–225.     

A case of exogenous lipoid pneumonia with marked elevation of serum KL-6 and interstitial lung shadows due to aspiration of liquid paraffin]

A 64-year-old man who ingested liquid paraffin as a laxative for over two years, was admitted to our hospital with a persistent interstitial lung shadow and marked elevation of serum KL-6. He had no overt symptoms although his chest radiograph revealed ground glass opacities in the left lower lung field and right middle and lower lung fields. We performed fiberoptic bronchoscopy. Exogenous lipoid pneumonia was diagnosed based on microscopic analysis of the bronchoalveolar lavage fluid that revealed the presence of lipid-laden alveolar macrophages. We instructed the patient to discontinue liquid paraffin ingestion and observed his clinical course. The chest radiograph and thoracic computed tomography revealed a tendency to improve and serum KL-6 decreased with time. Serum KL-6 may be an important index of the severity of exogenous lipoid pneumonia.     

Mycobacterium smegmatis pneumonia

Mycobacterium smegmatis is a non-tuberculous mycobacterium that is usually associated with soft tissue or wound infections in humans. Pulmonary infections secondary to this pathogen are rarely seen and occur only in patients with an underlying condition, such as lipoid pneumonia. This report presents the first case of M. smegmatis pneumonia in an otherwise healthy individual who had no predisposing condition.