At the Johns Hopkins Hospital in Bal timore, where hundreds of cases of ty phoid fever and of malarial fever are seen, many coming from the neighboring Ches apeake-Bay region and from the South ern States, the "typho-malarial" fever of Southern writers is unknown, and only two cases of true combined typhoid and gurgling, no rose spots; no tympanites, but rather retraction of the abdomen; and no intestinal hmorrhage. The only test is the recognition of the malarial parasite. 13edford Brown (Charlotte Med. Jour., Jan., '97).
It is often hard to exactly difTerentiate existing conditions into symptoms di reetly associated ss ith malaria and dis eases consequent on malaria. Diseases tnay exist at the same time as the ma laria, or may be induced by it; and only such conditions should be classified as symptoms as are the common conditions existing in malaria—for example, chills followed by fever, headache, sweating, vomiting, epistaxis, herpes labialis, bron chitis, and albumin in the urine. All malarial infection have been seen. The reports from foreign countries in general are the sante. I. P. Lyon (Amer. Jour. Med. Sciences, Jan., '99).
Particular mention must be made of those cases of wstivo-autumnal fever which are not characterized by a definite paroxysm and in which but a slight ele vation of temperature occurs, and that irregularly. The patients in whom this irregularly-manifested infection occurs inay complain only of headache, pain in the back and limbs, loss of appetite, and lassitude. This condition is, of course, accompanied by enlargement of the spleen, the characteristic malarial an minia, and the presence in the blood of mstivo-auturnnal parasites.
Pernicious Malarial Fever.—The de velopment of pernicious characteristics in malarial infections depends probably upon one or more of several conditions. These predisposing factors are divided by Mannaberg into: (1) individual predis position; (2) peculiarities of the para sites; (3) anatomical lesions.
1. There are persons who appear to possess a special predisposition to the de velopment of pernicious symptoms upon exposure to infection, and who as often as they are taken ill with malaria develop the disease in one of its severe forms. It is probable that in such subjects certain peculiarities, either chemical or anatom ical, may favor the elaboration of malarial toxins of more potent effect, or may influ ence the accumulation of infected blood corpuscles within certain capillary areas. In others the predisposition may be tem porary or acquired„ as in alcoholics, those exposed to excessive heat, or bodily weak ness incident to overwork and deficient nourishment. It has also been observed
that certain conditions predispose to the reference of pernicious symptoms to cer tain organs. Thus, it is observed by Bac celli that those whose work exposes them to the sun's heat frequently develop the comatose form, and that the same is true of alcoholic subjects, while persons pre viously suffering from intestinal catarrh are very likely to develop the choleriform type. In a highly-malarious region strangers who are unaccustomed to the climate are much more likely to develop pernicious malaria than the natives or those who have become acclimated.
2. Pernicious malarial fever is invari ably due to infection with one of the varieties of parasites belonging to the second, or mstivo-autumnal, group, and of these varieties the one most frequently concerned, according to Marehiafava and Bignami, is the malignant tertian para site. This being accepted as a fact, ma lignancy is found still further to depend upon the number of parasites existing in a given infection. In pernicious cases, while the number of parasites will be found to vary considerably, their number is always great. That the number alone is sufficient to explain malignancy many authorities dispute, and, while admitting the importance of their effect, the claim is made that pernicious symptoms arise in certain infections as the result of a higher degree of toxicity or virulency possessed by the infecting parasites.
3. The different anatomical lesions in pernicious malarial fever are sufficient to account for many of the malignant mani festations; these depend, for the most part, upon the occlusion of the lumina of the blood-vessels with the infected blood-corpuscles. Thus, by way of illus tration, as a result of obstruction in the cerebral vessels numerous punctiform hmmorrhages ensue and grave cerebral symptoms occur.
Pernicious malarial fever may show it self as such from the very onset, and this is particularly so in highly malarious regions, or the occurrence of pernicious symptoms may be preceded by several ordinary paroxysms. From what has been said regarding the localization of the malarial parasites in the vascular system of certain organs, it may readily be understood that more or less distinct types can be differentiated. The most frequently occurring type is the coma tose.