SPOTTED FEVER : II. AN EXPERIMENTAL STUDY OF FIéVRE BOUTONNEUSE

Several methods for the experimental study of the rickettsial diseases have been applied to fièvre boutonneuse. An analysis of the results has indicated that fièvre boutonneuse is a variety of spotted fever and that the etiologic agent is a rickettsia which belongs to the genus Dermacentroxenus and to the species rickettsi (Wolbach (6)). The distinctive morphology of the organism and its characteristic intranuclear clustering in ticks and in tissue cultures are the important criteria upon which this conclusion is based. Immunological, histological, and cytological observations of a confirmatory nature are also reported.     

TYPHUS FEVER : IV. FURTHER OBSERVATIONS ON THE BEHAVIOR OF RICKETTSIA PROWAZEKI IN TISSUE CULTURES

In tissue cultures grown at 32°C., typhus Rickettsiae increase rapidly within the cytoplasm of infected cells up to about the 14th day. At this time practically every cell is infected and the majority of cells are distended with organisms. This condition remains constant as long as successful cultures of the cells can be maintained (up to 52 days). Loss in virulence does not take place during this period in vitro. The number of Rickettsia-filled cells found in sections and the incubation period of the infection resulting from inoculation of cultures from each age group are definitely correlated. The behavior of typhus Rickettsiae in dividing cells is described and methods of spread of the infection other than by mitosis of cells are discussed. Normal tissues do not become infected in vitroto any considerable extent in spite of prolonged proximity to heavily infected cultures of scrotal sac exudate. Complete anaerobiosis and alterations in pH do not alter the intracellular location of the organism in tissue cultures. The organisms are not seen within nuclei of infected cells. They remain intact and infective for several weeks in cells which are kept alive but not multiplying. They disappear in less than 1 week, however, when the cells undergo degeneration.     

SPOTTED FEVER : I. INTRANUCLEAR RICKETTSIAE IN SPOTTED FEVER STUDIED IN TISSUE CULTURE

Spotted fever infection has been studied in tissue cultures grown at 32°C. The behavior of spotted fever Rickettsiaeis compared and contrasted with that of typhus Rickettsiae under similar conditions. The spotted fever organisms multiply extensively in the nuclei of cells where they form spherical clusters of various sizes. These structures are compared and contrasted with intranuclear inclusion bodies.     

Gonococcus endocarditis: Report of a case

A fatal case of gonococcus endocarditis with detailed autopsy findings is reported. Acute endocarditis followed a urethritis and affected an aortic valve which was already damaged by rheumatism.In addition to acute vegetative endocarditis of the aortic valve, autopsy revealed chronic productive changes in both mitral and aortic valves, subendocardial abscess with extension to the pericardium, diffuse suppurative and hemorrhagic pericarditis, acute intracapillary glomerular nephritis, acute focal interstitial nephritis, parenchymatous degeneration of the kidneys, infarction and suppuration of the spleen, degeneration and congestion of the liver, suppurative gastritis, pulmonary congestion, bilateral hydrothorax, ascites, conjunctival petechiae, suppurative leptomeningitis, gangrene of the legs, and a decubitus ulcer.     

ETIOLOGY OF OROYA FEVER : XVI. VERRUGA IN THE DOG AND THE DONKEY

In the experiments here reported, definite verruga lesions, in which the presence of Bartonella bacilliformis was established by culture or by passage to rhesus monkeys, were produced in a dog and in a donkey by inoculation of cultures or monkey passage strains. The reaction induced in these animals was entirely local, however; blood cultures were sterile. Histologically, the lesions produced were similar to those obtained in monkeys by inoculation of Bartonella bacilliformis, except for the presence of a marked polynuclear leucocytic exudate. In another donkey a lesion histologically suggestive of verruga was produced, while in one donkey and a horse the results of inoculation were negative or indefinite. The intravenous injection of a filtrate or of heat-killed cultures of Bartonella bacilliformis into two donkeys was followed by the appearance of large, soft, subcutaneous swellings, on various parts of the body, not resembling in any way verruga lesions.