Of cultures made with fluid withdrawn from 38 cases of sero-purulent pleurisy, 2S remained sterile, while 4 showed pure colonies of staphylococcus albus; 15 of the 28 were cases of pleurisy in which the affected region was the focus of a tuberculous infection; 1 was a case of pleurisy developing in a case of pulmo nary tuberculosis; 7 had suspicious signs at the apex; and 4 were apparent cures. Lemoine (Sem. Med., Mar. 27, '95).
There can be no doubt that the tuber cle bacillus is the most common cause of dry pleurisy and of pleurisy with serous effusion. This view is supported by many considerations. Persons with an inherited tendency to tuberculosis, as well as those with tuberculous disease of the lungs, are specially liable to these forms of pleurisy. Many of those who recover from the effusion afterward suf fer from the tuberculous disease, cially of the lungs. This termination is of too frequent occurrence to be merely a coincidence. Many French observers believe that 75 per cent. of all such cases are of tuberculous origin. This estimate is considerably higher than that of Eng lish and American observers, but the pro portion of cases of tuberculous origin is increasing year by year as the investiga tion of cases becomes more thorough.
Examination of the effusion by methods often gives negative results; but inoculation of the serum into guinea pigs, where large amounts-15 cubic centimetres or more—of the serum is injected, is much more successful, many of them becoming infected even when the fluid appeared sterile. Purulent ef fusion, if sterile, suggests tubercle bacil lus as a cause; if not sterile, it is ably always due to pneumococcus, strep tococcus, or some other microbe.
Of 101 cases of pleurisy examined post mortem, 32 were definitely tuberculous and 13 existed in patients with tuber culous lesions of the lungs without any definite proof of the tuberculous charac ter of the pleurisy. By far the com monest forms of pleurisy were sero fibrinous or fibrinous exudation, sec ondary to acute disease of the lungs, or occurring at the termination of chronic affections of the heart, arteries, or kid neys. Osier (Trans. Mass. Med. Soc., '93).
Two hundred cases examined with reference to the questions: Is there an " idiopathic," non - tuberculous, serous pleurisy? Is there an acute rheumatic pleurisy, equivalent to a previous acute arthritis? Are there serous exudates, with pyogenic organisms, which do not become purulent? Forty-three of the 200 eases were demonstrated to be tuberculous by find ing bacilli in the sputum or other prod ucts. Nineteen more had the suspicion
of tuberculosis in the history. Of the 200 cases only 7 gave a positive result when examined for bacteria. Out of 17 inoculations only two, belonging to the 7 just mentioned, gave positive results. These were: 1 case of sepsis and 1 of tuberculosis. The others were: meta pneumonic, 2; so-called idiopathic, 2, 1 of each showing streptococci and 1 pneumococci; 1 following gangrene of the lung with streptococci. The first 2 patients died. In the other 5 the exudates became purulent ultimately. Operation is not always necessary in such cases. Some recover spontaneously.
In all the rest of the 193 cases bac teriological examination was negative. Of 13 cases belonging to the class of demonstrable or suspected tuberculosis, inoculations in guinea-pigs gave positive results in 7. Of inoculations in 12 sus pected cases, 3 were negative. A similar proportion was observed in the so-called idiopathic cases, 0 out of 12 causing tuberculosis in guinea-pigs. This con firms the view that most cases of idio pathic pleurisy were tuberculous. Asch off (Zeit. f. klin. Med., B. 29, p. 440).
Tubercle bacilli are transported to the parietal layer of the pleura inclosed in leucoeytes. They may almost invari ably be found in the acute sero-fibrinous form of tubercular pleurisy, either in the liquid or in the false membrane. P6ron (Bull. de l'Acad. de MM., Oct. 27, '96).
Leaving out cancer of the pleura, all sero-fibrinous pleurisies are grouped into three classes:— I. Tuberculous pleurisy of the type known as acute, primary, or a frigore.
2. Pleurisy from miliary tubercles of the pleura in the course of a general tuberculosis.
3. Pleurisics secondary to lesions of the lung; (a) by subpleural infarcts; (b) by subpleural hepatization; (C) pul monary congestions. Le Damany (La Presse Mad., Nov. 2, '98).