Characteristics of a New Species of the Genus Listerella Obtained from Human Sources

Abstract

During the years 1933 and 1934, four individuals died at the New Haven Hospital from an infection, caused by an unusual organism, in which sepsis, focal necrosis of liver and meningitis were the predominant features of the disease. In a separate communication (Burn 1936), detailed clinical and pathological features of the fatal infection caused by this hitherto undescribed species of the genus Listerella will be described. The specific organism was isolated either during the clinical course of the disease or postmortem. It was the only organism demonstrable by cultural or staining methods in the lesions of three of the individuals and it was associated with Pneumococcus type III in the fourth instance. What proves to be the same organism has been described in the literature; firstly, in a non-fatal illness of an adult (Schultz, Terry, Brice and Gebhardt, 1934) and secondly, from cattle dying with suppurative meningitis (Jones and Little, 1934) (Seastone, 1935). More recently, another strain has been received through the courtesy of Dr. W. Allen of the Hartford General Hospital, Hartford, Connecticut. It was procured from a twenty-six-year-old male dying from meningitis within five to six days after the apparent onset of illness. At present, there-fore, there are six khown strains of this organism procured from recognized human infections and a similar strain of bovine origin. In view of the clinical and pathological findings in these cases, this new pathogen seems to have a special predilection for localization in the tissues of the central nervous system. A preliminary report (Burn, 1934) dealt briefly with the cul-tural and pathogenic properties of this bacterium. This com- munication purposes to present in greater detail studies of its morphological cultural, serological and pathogenic character-istics. METHODS Cultural and biochemical studies The cultivation of the organism from the blood stream or vis-cera requires only the usual meat-infusion broth and 5 per cent rabbit or human blood-agar plates as used routinely in any clinical or bacteriological laboratory and adjusted to pH 7.4. Further cultural, and biochemical reactions of the organism are determined with relation to carbohydrate fermentation, action on litmus milk, and gelatin and to the production of indol or nitrites. The sugar fermentation tubes contain 1 per cent carbohydrate prepared in a sugar-free base consisting of Dunham's peptone water plus Andrade's indicator. Fermentation tubes are inocu-lated with 0.1 cc. of an actively-growing strain of the culture and incubated at 37°C. for seven days. Changes in the fermentation are recorded daily. The final readings are based on observations made with four independent sets of carbohydrate fermentation. The final hydrogen ion concentrations for the strains are deter-mined in 1 per cent glucose broth by means of a glass electrode.