The exitus letalis is usually ushered in by coma of short duration, yet it may appear unexpectedly.

During the course of the disease different culminating symptoms -coma, convulsions, hemoglobinuria, edema of the lungs, hemorrhages, algor, etc.-may appear, to disappear again or produce rapid death. Expressed in Torti's fashion, these would be complicating symptoms in the course of a solitary fever. To describe all the possibilities and occurrences is not in the realm of this work.

The diagnosis of the pernicious typhoid form is readily made from the blood examination. Before Laveran's discovery it was exceedingly difficult for a physician in a malarial region to make a positive diagnosis, especially in the first days of the disease, between typhoid fever and pernicious malaria . From the melanemia alone the diagnosis is not sufficiently positive, since it might easily happen that in the small amounts of blood which we can examine under the microscope no pigment would be found. The parasites, on the contrary, whether pigmented or non pigmented, are met regularly and at all times; they are, therefore, an absolute criterion of inestimable diagnostic value.

Before the parasites were discovered the clinical symptoms and the result of the treatment with quinin made the basis of the diagnosis. It was a magnificent achievement of Torti's to recognize this method of diagnosis in the action of Peruvian bark. This criterion (ex juvantibus), which we are obliged even yet to apply in other cases,-syphilis, articular rheumatism,-on account of ignorance of the causal agents, has been adhered to up to the present time by physicians who are unacquainted with the malarial parasites or who refuse to recognize them. There can be no doubt that the diagnosis of malaria , ex juvantibus, led to a correct conclusion in innumerable cases, but it is likewise certain that it led, too, to innumerable errors, for malarial fever does not always react to quinin,-and this is especially true of the typhoid pernicious form,-and not every disease that improves after its administration can be regarded as a positive malaria.

The clinical symptoms have proved themselves to be even less practical than the quinin reaction, although numerous clever, observing clinicians used every effort to determine the differential diagnostic symptoms between typhoid pernicious malaria and typhoid fever. The number of these symptoms is so great as to discourage at the onset. Whoever has seen many cases of typhoid fever knows that this classic disease often refuses the frame made for it by the text books. Taking many cases together and drawing from them the most frequently occurring symptoms, a typical typhoid may be constructed that has a certain didactic and scientific justification that is even necessary, though it aids little toward a diagnosis of individual cases. In addition, typhoid fever often runs a different course in the tropics to that in the temperate zone, on account of the frequent manifestation of symptoms (coma, algor, etc.) which recall severe malaria .

The difficulty of making a differential diagnosis between these two diseases on a purely symptomatic basis is well demonstrated by the outcome of Colin's work. This accomplished clinician, who understood the symptomatology of typhoid and malaria in a way scarcely even equaled, was eventually obliged to conclude that remittent malaria may be "transformed" into typhoid fever.

The following are the principal points which Baccelli, who was thoroughly grounded in the subject, makes in the differential diagnosis*:

* This table has been taken from Rho's treatise.

Looking over these differential points, we must confess that they contain all the "typical" signs of the two diseases, and yet every one who has had any considerable experience with one or the other disease must acknowledge that he has seen a number of cases where they would not apply.

Fortunately, by the discovery of the malarial parasites, on the one hand, the Gruber-Widal reaction and the bacteria of typhoid fever, on the other, we have grown out of these clinical considerations and are in a position to make the diagnosis of malaria usually after one look into the microscope.

The prognosis depends on the individual condition of the patient. Alcoholics, persons with nephritis, arteriosclerosis, and other chronic diseases, as well as the badly nourished, are in more danger than the robust and healthy. The condition is especially dangerous in old age. Otherwise the mortality fluctuates according to the place and time.

Relapses

Like all the fevers caused by the small parasites, typhoid pernicious shows a marked inclination to relapse. The relapse may repeat again the typhoid character, and it sometimes happens that one person goes through the same form three or four times in one year.

Convalescence is more smooth and rapid than after typhoid fever. After one or two weeks, sometimes earlier, patients are completely recovered, excepting naturally what general disturbances may have taken place.

The following case of a very severe form of typhoid pernicious has been taken from Colin's book (p. 273)

Barbier, a fusileer in the Nineteenth Regiment, aged twenty two, for eleven months has lived in the Salara quarter (probably the most dangerous in Rome). On August 3, 1864, he was brought to my division, Saint Andre, with the symptoms of a moderately severe remittent: headache, flushed face, warm skin, coated tongue, marked thirst, restlessness, and vomiting. He was ordered 2 gm. pulv. ipecacuanha, 1.0 quinin sulphate, to be taken at 3 o'clock, and these were taken in my presence during the afternoon visit.

August 4: Continuation of the same symptoms. Was very restless during the night. During the visit epistaxis (seidlitz powder and 0.6 quinin sulphate).

August 5: Renewed epistaxis, pulse dicrotic, tongue dry, diarrhea, light meteorism.

On the following days the fever and diarrhea continued, with an increase in meteorism; the delirium became continuous, and on August 9 disseminated dry rales were noticed over both lungs.