“Diesel siphoner's lung”: Exogenous lipoid pneumonia following hydrocarbon aspiration
A 40-year-old male patient presented with a history of recurrent episodes of fever associated with cough and expectoration of 18 months duration. There was associated history of streaky hemoptysis on and off. There was no history of loss of weight, chest pain, wheezing or shortness of breath. Patient was a smoker with a smoking index of 300; however, no other significant personal or occupational exposure history was forthcoming. There was no past history of tuberculosis. He had been treated with multiple antibiotics over the past 1 year and empiric antitubercular therapy too had been administered, without any symptomatic relief. General physical examination was unremarkable. On chest examination, scattered crepitations were audible bilaterally. Rest of the systemic examination was normal. Baseline laboratory parameters were within normal limits. There was no leukocytosis. Liver and renal function tests and arterial blood gases were within normal limits. Sputum cultures were negative for bacterial, mycobacterial or fungal growth.\nChest radiograph [] demonstrated bilateral pulmonary infiltrates, more on the left lower zone and computed tomography (CT) of the thorax [] showed multifocal areas of low attenuation consolidation predominantly in the left lower lobe. There was no mediastinal lymph node enlargement, pneumothorax or pleural/pericardial effusion. Flexible bronchoscopy was performed, which demonstrated normal bronchial anatomy with no endobronchial growth or abnormality. Examination of the bronchoalveolar lavage (BAL) fluid and bronchoscopic lung biopsy demonstrated lipid laden macrophages in the alveoli and interstitium, confirming the diagnosis of lipoid pneumonia []. On subsequent enquiry, patient recollected history of multiple episodes of aspiration while siphoning diesel out of cars, when he used to work as an automobile mechanic. He had left the job 2 years back. A final diagnosis of exogenous lipoid pneumonia due to recurrent diesel aspiration was made. Patient improved symptomatically after bronchoalveolar lavage and was advised to follow-up regularly.\nAfter 2 months, patient presented with recurrence of fever associated with cough and expectoration. There was no symptomatic relief with a course of broad spectrum antibiotics and chest radiograph showed new onset infiltrates in the right lower zone. BAL fluid analysis demonstrated lipid laden macrophages. Stain for acid fact bacilli or fungus was negative. In view of recurrent symptomatic deterioration and no evidence of uncontrolled infection, patient was initiated on treatment with oral prednisolone (0.5 mg/kg/day), which was tapered over 6 weeks duration. A follow-up chest radiograph [] showed complete resolution of the radiographic abnormalities.