A system of practical medicine. By American authors. Vol. 3

by Unknown

If dyspnoea with deficient aëration of the blood, wasting, clubbed fingers, and expectoration persist after the expulsion or death of the hydatid, the probability is in favor of some associated pulmonary inflammation. When a hydatid cyst ruptures into the bronchial passages, there is serious likelihood that the patient may choke or suffocative dyspnoea supervene. The quantity of entozoal substance voided at any one time varies from a few microscopical fragments up to a pint or more of unbroken acephalocysts. The expectoration of acephalocysts may continue several months. Serious general pulmonary symptoms precede and follow this accident. When rupture has taken place into a bronchial tube, there are the usual physical signs of a pulmonary abscess or large vomica. The sac usually suppurates, and there is a constant expectoration of blood, pus, and half-putrid acephalocysts of excessive fetor, and often portions of gangrenous lung-tissue. With these symptoms the temperature is sometimes of a low, remittent type, with hectic and sweats. The symptoms resemble those of empyema or advanced phthisis, and may continue for months, until the patient, in most cases, sinks from exhaustion, unless relieved by the evacuation of the sac and its contents. When hydatids develop in the pleural cavity the signs are identical with a localized pleural effusion.

Nothing has been said to differentiate pulmonary-hydatid expectoration from cases where an hepatic hydatid cyst has burst into the lungs, and the diagnosis may be very difficult. The physical signs of enlarged liver are present, also the antecedent symptoms of disordered hepatic action, especially intestinal indigestion and the staining of the sputa with bile. If the cyst has undergone suppuration, the symptoms may be allied to those of hepatic abscess.

The nucleation of testimony favors the view that a latent or slow growth is by far the most common history of hydatids. Their duration is very variable: patients may harbor them for a long time unconsciously, even over a period of sixty years. This is corroborated by Finsen, who reports cases in which the disease lasted sixteen, eighteen, and fifty-two years, proving this by stating that these individuals had left the country where the disease was endemic, and were residing during these periods where the malady was rare.

TERMINATIONS.—30 or 40 per cent. of cases terminate in recovery if the cysts spontaneously burst, death being caused in others by suppuration and exhaustion. There is, in addition, the risk of sudden death from the rupture of a large cyst in the lung, and consequent filling up of the air-passages by its contents. The cysts may sometimes undergo atheromatous changes in which the hydatids resemble crushed grape-seeds. Microscopically, one finds a puriform fluid, plates of cholesterin, crystals of hæmatoidin, hooklets of echinococci, and débris of membranes. Again, the cysts may resemble a caseous or cretaceous tubercle without special characteristics. This may be looked on as a species of spontaneous cure. The growth of hydatid cysts may bring about by pressure such a state of chronic pulmonary engorgement that it affords a predisposing condition favoring the development of tubercular phthisis.

DIAGNOSIS.—The differential diagnosis is necessarily difficult. The nationality of the subject and the presence of a predisposing environment should always be remembered. If the disease progresses rapidly without interference, the diagnosis may be complicated by the development of patches of bronchitis or pneumonia with rusty sputa. The bronchitis is, however, local, which, taken with the physical signs of a cyst, may be suggestive. The only absolute evidence of the existence of hydatids in the lungs, whether primary or secondary, is the appearance in the sputa of the characteristic cysts or portions of them, such as fragments of the hooklets of the echinococci. This, unfortunately, occurs as a late accident in their history. If the boundaries of the cyst can be recognized, it is justifiable to resort to paracentesis, and thereby withdraw some fluid for examination. The physical signs of local serous effusion, globular in shape, not evenly distributed around the circumference of the chest, is one of the best differential evidences between hydatids and pleural effusion. Moreover, there is no fever in hydatids unless after rupture, or with extensive phthisical complication, while there is a history of fever in some stage of most cases of pleurisy. Hydrothorax is differentiated through its being bilateral and by its etiology. From local encysted pleurisy the only resort is exploratory puncture and the question of the probabilities in each case. In the same way paracentesis removes doubt whether there be mediastinal tumor, solid tumor of the lung, or circumscribed pneumonic abscess; in the latter the general history of each case is helpful. From phthisis we must have recourse to the physical diagnosis already mentioned as belonging to hydatids. An unbroken cyst in the liver, high up and far back on its convex surface, may not be distinguishable from one in the base of the lung immediately over the liver or one in the cavity of the pleura.

PROGNOSIS.—According to Reynaud, this depends on—1, whether the hydatid is single or multiple; 2, whether the pressure is exercised on blood-vessels or bronchi; 3, if hydatids are discovered elsewhere; 4, size of cyst; 5, alterations in the walls of cysts; 6, whether complicated with any other disease or independent.

If there is a tendency to pulmonary phthisis, inherited or acquired, or if this disease exists as a complication, it forms an unfavorable element in the prognosis. Persons once affected with hydatids are more susceptible to a second invasion of the parasite. The practicability of treatment by tapping is also an element in the prognosis.

TREATMENT.—Naturally, the preventive treatment rationally deduced from the now distinctly-understood causes should be practised. The water-supply should be protected from sources of contamination, and in addition the inhabitants of countries where the disease is prevalent should, as far as practicable, use boiled or stone-filtered water and refrain from eating water-cresses or plants of like character wherever these are liable to be contaminated.

Many drugs have been administered, among them the bromide and iodide of potassium; solutions of salt are also said to be deleterious to the life of the echinococcus; Laennec even prescribed salt baths. Tincture of kamela has been recommended by Hjaltelin, a physician in the employ of the Danish government in Iceland. He administered it in doses of thirty drops daily to adults, continuing its use during a month or more. It has a distinctly irritating and destructive effect on the acephalocyst (Bird). Turpentine, from its well-known anthelmintic powers and ready diffusibility, has naturally suggested itself as a remedy, and according to some has proved of great service in many instances, while in others it has signally failed.

Paracentesis is generally regarded as the most efficacious treatment, and may be carried out upon the principles usually applied in the treatment of hydrothorax. Bird recommends that the trocar should be not less than six inches long and of the smallest diameter that is made, always providing that it is strong enough to bear the strain of a firm pressure. Cysts can be tapped in this manner even when they are separated from the chest-wall by quite a deep layer of lung-substance. This treatment should be practised at the earliest possible period in the life of the cyst. Speaking of the aspirator, he says that cases always do so well if tapped early enough with the simple trocar and canula that aspiration is not required. The gradual expansion of the lung as the cyst is emptied is sufficient to expel all the fluid, especially if aided by the effects of coughing. In exceptional cases of old standing, where there is a thick adventitious external wall to the cyst, which is generally closely adherent to the ribs, or again in cysts of the pleura, a free antecedent incision of the external tissues is sometimes required. It has been suggested by different authors that tincture of iodine should be injected after aspiration to secure the obliteration of the cyst by inflammation. The injection of carbolic or salicylic acid under the same conditions has been practised with success by Mosler and others.