Bronchoalveolar Lavage in Liquid Paraffin Pneumonitis: Discussion (4)

Once in the bronchial tree, liquid paraffin is removed by mucociliary transport only with difficulty. In 1932, Proetz showed that liquid petroleum hinders the flow of mucus transported in vivo on rabbit nasal epithelium. More recently, King et al found that viscous substances, such as oils, are not or are slowly transported in vitro on the ciliated epithelium of frog palate. Thus, aspirated liquid paraffin could depress the bronchial mucociliary transport by altering the viscoelastic properties of secretions.
Once in the alveolar spaces, mineral oil is emulsified and engulfed by the AM. Although some paraffinladen AM may penetrate into the interstitial tissue and reach the peribronchial lymphatics and hilar lymph nodes, most of the mineral oil remains within the alveoli, free or in the AM. Since the macrophages cannot metabolize the chemically inert, nonsaponi-fiable oil, they disintegrate after some time and liberate the intracellular oil into the alveoli. This alveolar free liquid paraffin cannot be removed up to the pharynx by the depressed mucociliary transport and a vicious circle is set up which accounts for the chronicity of this disease, even several years after discontinuation of the liquid paraffin intake. buy antibiotics online
In order to further investigate the inflammatory response induced by liquid paraffin in the lung, we have also examined the different types of cells recovered in the BALF from these seven patients. The numbers of lymphocytes, eosinophils, and neutrophils were increased on the surface of the lower respiratory tract. These findings support that a local cell-mediated inflammatory response induced by liquid paraffin may be important for the development of interstitial fibrosis in liquid paraffin pneumonitis.