the severity of the pyrexia alone. Occasionally a second relapse occurs after another interval of apyrexia; and even third and fourth relapses have been observed, though very rarely.

Morbid Anatomy.-The essential lesions of enteric fever occur in the Peyer's patches and solitary glands of the small intestine. These become infiltrated with lymph-corpuscles, and a Peyer's patch so affected swells, and projects one or two lines upon the inner surface of the intestine; it is gray, fawn-colored, or pink, but the surrounding mucous membrane may have its natural color. The lymph-corpuscles at first multiply in the follicles, but subsequently infiltrate the mucous membrane above and the deeper structures below. As the patches become larger they acquire a creamy-white color,

TEMPERATURE IN A CASE OF TYPHOID FEVER WITH RELAPSE.

and about the tenth day or a little later they begin to ulcerate or slough; this may begin by a superficial abrasion at one point of the surface, which becomes deeper and deeper until a great part of the gland is removed, or a whole patch may slough at once. When the slough is still adherent, it often. has a yellow color from absorption of bile. By these processes the muscular coat or the peritoneal covering may be exposed in the floor of the ulcer, and finally, the peritoneum may slough, ulcerate, or tear, so that the contents of the bowel escape into the peritoneal cavity, and set up a fatal peritonitis. The stage of ulceration generally occupies part of the third week, and toward the end of that time, in favorable cases, the process of healing by cicatrization begins. Ulceration does not necessarily occur. In mild cases the inflammatory swelling subsides without further destructive change. The

number of Peyer's patches affected is very variable, and though the cases with severe diarrhoea generally have extensive inflammation of the bowel, there is no necessary correspondence between the extent of ulceration and the severity of the other symptoms. The patches near the ileo-cæcal valve are those first attacked, and the process spreads upward. The change in the solitary glands of the lower end of the ileum is of the same kind, and in some cases the solitary glands of the large intestine (mostly the cæcum) are also enlarged and ulcerated. Coincidently with these lymphatic structures of the intestines, the mesenteric glands are inflamed; they are enlarged, fleshy, pink, red, or purplish, and their histological changes resemble those of the Peyer's patches. Sometimes they break down so as to contain one or more small collections of fluid resembling pus, which in rare cases burst into the peritoneum; but more generally they become cheesy or calcareous. The spleen is commonly enlarged, dark in color, and, in later stages of the disease, softened. The liver is often hyperæmic, and softer than natural; the kidneys are congested, and in both these organs the gland cells are granular. The heart is often soft and flabby, its muscular fibres being in a state of fatty and granular degeneration. The voluntary muscles are also the subject of a degeneration first described by Zenker in typhoid fever, but now known to occur in typhus, and other prolonged febrile conditions. The muscular fibres are converted into a homogeneous, colorless, waxy-looking material, forming cylinders, which break up into fragments, and finally crumble into a granular detritus. This change is most common in the adductors of the thighs, and in the recti abdominis; and it is sometimes accompanied with hemorrhage, or the broken-down muscle may form a kind of abscess. The lungs are either oedematous, or congested at the bases; or, in occasional cases, actual pneumonia is present.

A bacillus, constantly present and not known to occur under other circumstances, has been described by Koch and Gaffky. It has been found in the stools, in the blood, and in the albuminous urine during life, and in the organs after death.

Complications.-The most important complications are those connected with the intestinal lesions. Peritonitis is a frequent cause of death. It arises most commonly from perforation of the floor of one of the ulcerated Peyer's patches, through which the contents of the bowel are extravasated into the peritoneal cavity; but it occasionally happens, from extension of inflammation through the peritoneal coat, that peritonitis occurs without any perforation being discovered; and it has also been caused in rare cases by the softening of inflamed mesenteric glands, and of infarctions in the spleen. Perforation of the bowels takes place in about 10 per cent. of cases of enteric fever. It commonly occurs during the third, fourth, or fifth week, and generally, in severe cases, with marked intestinal symptoms. Its onset is often marked by acute pain, collapse, and perhaps rigors; the abdomen becomes

distended and tender, the pulse is small and rapid, and a fatal result soon ensues. But its advent may only be marked by collapse and increased distention; and in very severe cases, with much distention of the bowel, as well as coma and delirium, there may be no sign to indicate peritonitis with certainty, so that perforation and peritonitis are occasionally found postmortem when not suspected during life. It is important to remember that as long as the ulcers remain unhealed there is a possibility of a rupture taking place; and that such a rupture may be induced by any disturbance of the bowel, as by vomiting, defecation, or the exertion of sitting up, and the administration internally of indigestible food or aperients; and thus even cases which are running a mild course have a fatal termination from this cause. A slight amount of bronchitis is frequent in enteric fever, but occasionally it is so severe as to constitute a very serious complication. The face may be quite livid, and a more or less venous tinge may be given to the whole surface; the chest is filled with moist and dry râles, and there is expectoration of mucus or muco-pus. Ulceration of the larynx occurs sometimes in severe cases. The ulcer is situate commonly over the arytenoid cartilage, and this may even be exposed and in a state of necrosis. Sometimes the cartilage has been found in an abscess that seems to have arisen independently of ulceration. Hoarseness may be the only symptom of the laryngeal complication, but there is often complete aphonia. As a result of the laryngeal ulcer, subcutaneous emphysema has been recorded by Dr. Wilks and by Ziemssen; air being forced during expiratory efforts from the larynx into the connective tissues. Cicatricial stricture of the glottis has also been recorded in cases that recovered. Aphonia itself may occur, temporarily, without any evidence of ulceration. Pneumonia, sometimes becoming gangrenous, and pleurisy, occasionally occur. Meningitis is quite rare as a complication of enteric fever, and the cerebral symptoms commonly occurring are quite independent of cerebral inflammation. I have seen double optic neuritis in a case of enteric fever, but it is not common. Otorrhea may occur during or after the fever, and may lead to deafness, or to the more serious conditions of septicemia and meningitis. Other local inflammations occasionally occur either during the fever or during convalescence, and may considerably delay recovery, such as parotitis, which may be followed by suppuration, or extensive infiltration of the neck; orchitis; periostitis, especially of the tibia; cancrum oris; and facial erysipelas. In severe cases bedsores may form, in spite of careful nursing. Thrombosis of the femoral vein occasionally occurs during early convalescence, leading to cedema of the foot and leg, and tenderness in the course of the vein. Generally, this recovers without much trouble, but the thrombosis may extend into the large abdominal veins, or portions of clot may be detached, and lead to pulmonary embolism and death. Tuberculosis has sometimes developed after enteric fever; but there is considerable resemblance between the two conditions, and it

is possible that some cases of early tuberculosis have been mistaken for enteric fever.

Varieties of Enteric Fever.-There are few diseases more variable than enteric fever. Though its duration is characteristically three weeks, it may be as short as ten days or as long as five or six weeks: and though short attacks may sometimes be fairly represented as abortive attacks, they may be followed by a relapse of precisely the same nature and duration. Sometimes the temperature begins to fall in the manner described (p. 50), and then, before reaching the normal, persists in its remittent type, oscillating between 100° (morning) and 102° (evening) for eight or ten days, so that the fever is prolonged into the fifth week, although the patient is feeling better every day, and has no obvious complications. In other cases the prolongation of the fever corresponds with a continuance of the high fever characteristic of the second week, and these are generally severe cases. In some cases the illness is so slight that patients go about their ordinary occupations, until, perhaps, an indiscretion in diet, or the use of aperients, given in ignorance, leads to a fatal perforation. A bilious form of typhoid has been described, and in a few cases jaundice occurs; and ataxic and adynamic forms have been described, but these terms simply indicate the predominance of symptoms in one or other system of the body. Enteric fever is often very mild in children, often of short duration, and associated with less extensive disease of Peyer's patches than in the average of adult cases. The remissions of temperature, which are well marked in the latter half of the illness in adults, are often still more marked in children, and formerly led to the description of an "infantile remittent fever." This is, however, now known to be nothing more than enteric fever, and there is no object in retaining a name which is likely to mislead.

Diagnosis. A great number of diseases may be confounded with enteric fever, from the variety of forms which it assumes, and from the frequency with which its own typical symptoms are absent, or badly marked. In early stages it is distinguished from other fevers by the absence of characteristic eruption. By the fifth day of the illness, the rash of typhus, smallpox or scarlet fever would have developed; the appearance of rose spots a few days later confirms the suspicion of enteric fever. Later stages present a resemblance to different diseases, according as the head, chest, or abdomen shows the most prominent disturbance. Thus, the early headache of typhoid, and the subsequent delirium, may suggest meningitis, and the two diseases are frequently confounded together. Sometimes it is impossible to distinguish. them until later stages, when optic neuritis or a local paralysis, squinting or convulsion, or the obstinately retracted abdomen may decide for tubercular meningitis; or, on the other hand, the increase of abdominal symptoms, with the presence of spots, may prove it to be enteric fever. In this latter, headache rarely continues beyond the tenth day. When pulmonary symp

toms are marked, acute tuberculosis may be simulated by the abundant bronchitic râles and crepitations, accompanied by a remitting fever. The abdominal diseases which may be confounded with typhoid fever, are, especially, tubercular peritonitis and typhlitis or perityphlitis. In both there may be high fever, abdominal distention and tenderness: and in tubercular peritonitis the stools may be frequent and yellow from accompanying tubercular ulceration. Pyæmia, and the septicemia accompanying abscesses of the liver, or about the kidney (perinephritis), may closely simulate typhoid fever, and an allied condition, ulcerative endocarditis, is not unfrequently mistaken for it. The symptoms in favor of endocarditis are the existence of a murmur, or of irregular action of the heart, hemorrhages under the skin, or other evidences of emboli, such as obliteration of the arteries at the wrist or ankle, abundant albuminuria, or retinal hemorrhages; rigors may be present, and the temperature often oscillates freely. Trichinosis, the disease caused by the multiplication of the trichina spiralis within the body, has been mistaken for typhoid fever; it is distinguished by severe muscular pains, oedema of the eyelids, and sometimes of the whole body; and there are no rose spots or enlargement of the spleen.

Prognosis. The mortality of enteric fever varies in different epidemics from 5 to 20 per cent. Complications contribute largely to the deaths, and their occurrence will modify the prognosis at any time. Apart from them, the intensity of the fever is an important guide. If the temperature is, although high at the end of the first week, subsequently never above 103°, the case is favorable; if the temperature is maintained at 104° or higher throughout the second week, it is much more dangerous. Some cases sink rapidly by the twelfth, eleventh, and tenth days, or even before this. Perforation is very rarely recovered from. Hemorrhage has been thought to be of rather favorable import, but this is not really the case; it is certainly well represented among the fatal cases, and a severe hemorrhage, if it does not lead to a fatal result, renders the patient very anæmic, and considerably prolongs convalescence. Much abdominal distention, severe general bronchitis, or feeble and irregular heart, are all unfavorable.

Treatment. The patient should be in bed in a well-ventilated apartment, and the same rules should be carried out as to nursing as in the case of typhus fever. The special danger of perforation and hemorrhage from the ulcerated bowel should never be lost sight of. Rest should be absolute; the patient should be allowed no exertion, and a bed-pan should be used when he wishes to pass his motions. The diet should consist chiefly of milk, of which two, three, or four pints may be given daily, in regular quantities, every one or two hours, or more frequently. Beef-tea may also be given, but it is said sometimes to increase the diarrhoea, and is certainly not as nutritious as milk. In some cases, where milk is taken badly, it may be peptonized by the use of Benger's liquor pancreaticus. As to medicinal