Acute and latent pneumonitis after subcutaneous injections of silicone in transsexual men.

We evaluated 13 transsexual men who were hospitalized for symptoms resulting from illicit subcutaneous injections of silicone. Patients with acute silicone pneumonitis were admitted because of fever, bilateral pulmonary infiltrates, and hypoxemia (mean PaO2, 58 +/- 14 mm Hg). Most patients in this group had received new silicone injections within hours of admission, but one presented with the same clinical syndrome a few hours after a brawl. The alveolitis of acute silicone pneumonitis was characterized by increased numbers of alveolar macrophages, neutrophils, and eosinophils (p less than 0.05 compared with those in normal persons with a similar smoking history). Evidence of alveolar hemorrhage was also present in some cases. Alveolar macrophages contained large, pleomorphic, cytoplasmic inclusions, which were identified as silicone by atomic absorption and infrared spectrometry. Patients with latent silicone pneumonitis underwent clinical study at much longer times after the silicone fluid injections because they developed local inflammatory phenomena at the sites of previous injections. Pulmonary function studies usually showed slight restrictive changes, and bronchoalveolar lavage disclosed abnormalities similar to those found in patients with acute silicone pneumonitis, although to a lesser degree. Thus, illicit silicone fluid injection carries a serious respiratory risk since it can induce pneumonitis, followed in some patients by respiratory failure.