Gummata are more frequently situated in the middle or lower lobes of one or both lungs, and are defined by a boundary layer of fibrous tissue. Fibroid development may ensure their adhesion to the visceral and costal pleura. They are gray or yellowish-gray, hard, well-defined nodules, of varying size and number, occurring as single large masses surrounded by normal or compressed lung. In the centre is found a diffluent material, not unlike the centre of a scirrhous nodule, similarly enclosed in a limiting fibrous investment from an inch to many inches thick. In the condition of the neighboring pulmonary substance a difference may be observed between gummatous and tuberculous nodules: the latter occur in more numerous masses, usually small, and the entire lung is more or less diseased; while in syphilis extended districts of non-affected lung occur in the neighborhood of gummata. Whenever gummatous lesions in the lungs exist a history of pustular eruptions, laryngitis, arterial lesions—in fine, some indication of general systemic syphilitic poisoning—can always be found. Fournier thinks there are five anatomical points of distinction between syphilitic gummata and tubercle: "1. Tubercle involves the upper part of both lungs; gummata one lung, and may be limited to a portion. 2. Gummata are few as a rule, solitary; tubercles sooner or later become confluent. 3. Gummata are larger than tubercles, never miliary in form. 4. Gummata are always yellow or white, never transparent like miliary tubercle. 5. Until softening takes place gummata are of more equal consistence than tubercles, and if they soften do not break down, wholly owing to the capsule. Histologically, there is no difference in structure." Gummatous formations may be found on the pericardium and heart and in the thoracic and abdominal walls. Clinically, the most important pathological feature is that large districts of healthy lung are interposed between the affected districts; this is not so in ordinary phthisis.

Bronchial Lesions.—The syphilitic like the scrofulous are predisposed to catarrhal inflammation, and this may spread down the bronchial tubes, giving rise to a general bronchitis; a coexistent laryngitis may or may not exist. Enlargement of the bronchial glands is frequently combined with the syphilitic pulmonary process. When the glands are enlarged they present a firm pigmented character, varying in size from a hazelnut to an egg, and the connective tissue surrounding them is usually infiltrated. Subsequently, owing to the pressure of the mediastinal growths, the bronchi are narrowed and more or less occluded; the same effects are occasioned in the smaller bronchi by the pressure of the new growth which develops along their lumen. The effects of bronchial narrowing or occlusion produce serious mischief in the lungs proportioned to the degree of obstruction. By the retention of the bronchial secretions the air-supply to the vesicles is interfered with; emphysema with or without asthmatic symptoms or atelectasis may ensue. Further, the results of bronchial narrowing affect the circulation through the lungs, and in combination with atelectasis very intractable local bronchitis may be developed; and, with or without atheroma, hemorrhagic infarctions may occur, with a form of pneumonia which has been described by Fuchs as apneumatosis. The narrowing of the bronchial tubes in specific fibroid phthisis affords a means of differentiating this disease from non-syphilitic fibroid phthisis, in which the tubes are widened. Cases have been reported of nodules of syphilitic new formations in the mucous membrane of the superior and inferior extremities of the trachea and larger bronchi. The nodules ulcerate, and in healing cicatricial bands of fibrous tissue are formed which cause contraction of the tracheal tube transversely or diminish its length. These lesions resemble tuberculous ulceration, but they differ in the nature of the initial neoplasm by the formation of cicatricial tissue and by the tendency to stenosis of the tracheal tube. The cutaneous syphilides, mucous patches, the exostoses of the bones of the cranium help to demonstrate the connection of the marked cachexia with syphilis rather than scrofula.

SYMPTOMATOLOGY.—As the pathology of syphilitic pulmonary processes is intertwined with the pathology of many other forms of phthisis pulmonalis, so the symptoms must be common to those obtaining in other forms of pulmonary disease. They are insidious and gradual in their development, and may be classified as the subjective, the physical signs, and the objective phenomena. The subjective symptoms may be present without noticeable departure from an appearance of health. There may be difficult respiration with more or less dyspnoea, especially in the mornings and evenings, besides a sense of heaviness and oppression in the chest, with a feeling of inability to inflate the lungs. These symptoms may be increased on exertion, respiration becoming wheezing, with imperfectly-developed asthmatic attacks. Hoarseness, with varying degrees of aphonia, more or less dysphagia or unequal pupils, may be present. Nearly all of these symptoms may be accounted for as indicative of mediastinal pressure or irritation of the pneumogastric nerve by the enlargement of the bronchial glands. The catalogue of phenomena may be present in whole or in part, and the intensity of their manifestations may vary from time to time in the history of a single case. If the bronchial glands are much enlarged, a sense of discomfort, oppression, and uneasiness at the root of the neck may be experienced, which increases until actual pain is felt, located in the back between the scapulæ, but sometimes radiating through the intercostal nerves around the chest. Cough, as a rule, is an early symptom, usually dry, paroxysmal, and associated with dyspnoea, or there may be bronchial catarrh, with a relative amount of expectoration. Syphilitic disease of the larynx may occur coequal with the pulmonary trouble, and some of the above symptoms may be thus explained and many others added. Rheumatic and nervous symptoms, including sleeplessness and deterioration of the blood-crasis, may testify to the syphilitic infection of the blood.

When a physical examination of the chest is instituted, thickening of the head of the periosteum of one or both clavicles, substernal tenderness, thickening of the tibial periosteum, are usually detected. Prominent among the physical signs are the evidences of enlargement of the bronchial glands. According to Guéneau de Mussey, percussion over the spinous processes of the cervical vertebræ in the course of the trachea reveals in a healthy subject a distinct tubular sound down to the point of bifurcation of the trachea at the level of the fourth dorsal vertebra. Opposite the fifth and downward we get the lower-pitched pulmonary resonance. When the tracheal and bronchial glands are enlarged, the tubular sound over the upper dorsal vertebra is replaced by dulness, which may contrast sharply above with the tracheal and below with the vesicular resonance.

The respiratory murmur will be feeble in volume and limited to inspiration, especially over the interscapular region. Over one or the other bronchus the respiratory murmur may be more high pitched than in health, and slightly exaggerated on one side or at the base of the chest. The rhythm is often jerky and paroxysmal; the paroxysms are more or less constant, but are liable at times to increase.

The additional physical signs in syphilitic phthisis, unassociated with gummata, are those shared by other forms of fibroid phthisis, and do not require particular description here, as increasing dulness, varying degrees of bronchial breathing, and bronchophony. A peculiar alveolar rustle, resembling the sound produced by the rumpling of wall-paper, has been alluded to as characteristic.

Inspection or palpation sometimes reveals changes in the contour of the chest, with displacement of the movable thoracic viscera, as in fibroid phthisis. When cavities occur, the physical signs necessarily correspond to those of other varieties of phthisis at this stage.

When a gumma is large enough to be recognized by physical examination, one finds dulness or flatness on percussion, confined to a section of the chest, and not occupying its semi-circumference, as in pleural effusions. The vocal fremitus is suppressed in proportion to the size of the gumma. The respiratory murmur is abruptly cut off over the area of flatness, but it may be only distant bronchial breathing. The vocal resonance is absent or is distant bronchophony. Around the gumma the respiratory murmur is usually very feeble or scarcely audible, generally without râles unless they are due to neighboring congestion. The percussion resonance is good or exaggerated. Proportionate vicarious functional activity prevails in the opposite lung. If the gumma be large, the heart's impulse may be displaced to the left or right, and dyspnoea may occur as in case of pleural effusions. In this stage, owing to irritation of the bronchial mucous membrane, there may be expectoration of a tough, glairy mucus, or as a gumma softens the expectoration may become purulent.

The objective phenomena vary: the chest is often well developed, the body fairly nourished, and constitutional symptoms of a severe character may be wanting. The patient may be capable of hard physical labor, even though a considerable part of the lung be affected. Moxon relates a case of a man "employed in carrying sacks of grain who was suddenly killed, and who had fibroid infiltration of a great part of the left lung and part of the right, and besides scars in his liver and testes." But in some cases the complexion is pallid and waxy, indicative of cachexia associated with digestive disorders, with night-sweats, and a variable but low thermometrical record. Usually, the progress of the disease is slower in syphilitic than in tubercular phthisis, but when the systemic poisoning is grave and many other organs are coincidently involved, the progress is more rapid; but the process peculiar to syphilis is often past, and the patient suffers from simple catarrhal phthisis with formation of cavities and softening gummata. Diarrhoea and night-sweats are said to be less frequent than in ordinary phthisis, and the pulse is slower. Hæmoptysis occurs infrequently, because the process in the lungs is chiefly fibroid; but it is possible through the rupture of newly-developed blood-vessels in the new formation in the lung or hemorrhagic infarction through the rupture of atheromatous vessels.

DIAGNOSIS.—This depends mainly on the history of the cases, the prior or coexisting syphilitic lesions, especially laryngeal processes, cutaneous syphilides, exostoses, perforation of the palate, substernal tenderness, and the thickening of the tibial periosteum or that of the head of one or both clavicles. Family immunity from phthisical tendency, recovery from lesions usually incurable if they have any other than a specific origin, are suggestive of pulmonary syphilis. If a patient retains flesh and strength beyond the natural expectation considering the serious lesions of the lungs, the fact is of relative importance when considered in connection with the other diagnostic features. The distribution of specific lesions is variously located by different authors. Grandidier found induration affecting the middle lobe of the right lung in 27 out of 30 cases believed by him to be specific phthisis; the surrounding lung contained large areas free from disease. This tendency to localization in portions of the lungs, leaving large areas free from disease, is of value in diagnosis.