Lipoid pneumonia presenting as non resolving community acquired pneumonia: a case report

Abstract

Introduction: Lipoid pneumonia is a rare form of pneumonia caused by inhalation or aspiration of fat containing substances like, petroleum jelly, mineral oils, few laxatives etc. It usually presents as insidious onset chronic respiratory illness simulating interstitial lung diseases. Rarely, it may present as an acute respiratory illness, specially, when exposure to fatty substance is acute and/or massive. Radiologically, it may mimic carcinoma, acute or chronic pneumonia, ARDS, or a localized granuloma. Diagnosis of LP requires demonstration of lipid laden macrophages in sputum, bronchoalveolar lavage fluid or fine needle aspiration cytology/biopsy from lung lesion. Treatment of this illness is poorly defined and constitutes supportive therapy and corticosteroids.

Case presentation: A 20-year old Indian farmer was referred to us with a diagnosis of non resolving community acquired pneumonia. Respiratory examination revealed signs of consolidation. Chest radiograph revealed findings suggestive of bilateral consolidation. Sputum and blood culture were sterile. He was treated with prolonged course of various antibiotics without any significant response. For evaluation of non resolving pneumonia fibreoptic bronchoscopy was done. Bronchoalveolar lavage fluid and biopsy from lung lesion showed lipid laden macrophages. Hence diagnosis of lipoid pneumonia was made. Patient was treated with course of corticosteroids with good response. Literature on this rare entity is discussed.

Conclusion: Lipoid pneumonia is a rare form of pneumonia which rarely present acutely resembling community acquired pneumonia and requires high degree of suspicion for diagnosis. Its treatment is difficult and poorly defined. However, prolonged corticosteroids may be effective.

Figure 1

Frontal chest radiograph (figure 1a) reveals extensive consolidation involving mid and lower zones of bilateral lung fields. Follow up chest radiograph (figure 1b) obtained three months later shows significant clearing of consolidation.

Figure 2

Mediastinal (Figure 2a) and lung window (figure 2b) of non-contrast computer tomographic scan of chest reveals consolidation in the right middle lobe, lower lobe, and also left lung. Few low density areas (arrow) are seen within the middle lobe consolidation.

Figure 3

Bronchoalveolar lavage fluid cytology showing lipid laden macrophages.

Figure 4

Line diagram showing TLC response to corticosteroids.