Alveolitis due to hair-spray. Ultrastructural observations in two patients and the results of experimental investigations.

Observation of two patients with hair-spray induced lung disease have prompted us to study the ultrastructure of the lung lesion. We have compared the results with experimental lesions in animals injected with hair-spray extracts and with human monocyte cell cultures exposed to hair-spray. The lungs show a chronic alveolitis with a striking granulomatous reaction including macrophages and multinucleated giant cells of the foreign body type. The intraalveolar and interstitial macrophages and the giant cells all contain PAS-positive material. Ultrastructurally distinct lamellar inclusions are found in the secondary lysosomes of the macrophages and giant cells. Identical structures can be produced in animals injected with hair-spray extracts and with polyvinyl-pyrrolidone and -acetate (PVP/PVA), which are regular ingredients of hair-sprays. Large, presumeably polymeric particles (PVP/PVA) are ingested by giant cells. This "gigantophagocytosis" is associated with the fusion of mononuclear phagocytes and leads to the genesis of giant cells. In cell cultures of human blood monocytes hair-spray extracts and PVP/PVA induce maturation and aggregation of these cells, with PAS-positive cytoplasmatic inclusions. The development of multinuclear giant cells in these monocyte cell cultures is also seen. These observations suggest that hair-spray induced lung disease is caused by the prolonged and extensive body response of the local mononuclear phagocyte system (MPS). Overstimulation of the MPS leads to a quantitative and qualitative change which is followed by a partial blockade of this system. The alveolitis is a consequence of the foreign body response to inhaled hair-spray substances.