Tertiary syphilis of the lung and its diagnosis.

Acquired syphilis of the lung is a rare condition, but the diagnostic criteria are so variable that it is difficult to assess the degree of rarity. To quote Lord (1925), " the diagnosis cannot be made with assurance during life, and is often uncertain at the post-mortem." Lord himself found no proved cases in the course of 4,705 routine necropsies at the Massachusetts General Hospitai, although three were suggestive ; on the other hand, Symmers (1916) records the diagnosis in 12 out of 4,880 necropsies at the Bellevue Hospital, New York. In spite of its rarity there is no lack ofcase records of acquired pulmonary syphilis, and these have been adequately reviewed (Karshner and Karshner, 1920; Carrera, 1920; Howard, 1924; McIntyre, 1931); and fresh cases are published at the rate of half a dozen every year. But again there is a distinct variation in the reserve with which the reviewers accept the diagnosis. Howard, writing in 1924, found 200 cases in the literature, but McIntyre, seven years later, could accept only 97 between the years 1854 and 1920; of these, roughly half were diagnosed at necropsy, and the remainder on radiological evidence or by response to antisyphilitic treatment. In the last century the difficulty lay in differentiating pulmonary syphilis from tuberculosis, and, before the discovery of the tubercle bacillus by Koch in 1882, there is little doubt that many cases diagnosed as pulmonary syphilis were in fact tuberculous. But since the demonstration of the Spirochaeta pallida by Schaudinn in 1905, and the introduction of serological techniques, it has been possible to diagnose pulmonary syphilis with a greater degree of confidence, always bearing in mind that it is no rarity for a tuberculous patient to have a positive Wassermann reaction as well. We present our case because it illustrates the difficulties of clinical diagnosis, and because the fresh pneumonectomy specimen gives a clearer pathological picture than is usually offered in published articles on this condition.