A Micrococcus Causing a Condition Clinically Very Similar to a Mycosis.

Abstract

Morphological and Staining Characters. This coccus for which I have suggested the name M. myceticus at times morphologically resembles the gonococcus, at times an ordinary streptococcus. Certain strains when recently isolated are practically gram negative, but after subculturing they usually become gram positive.

Cultivation and Isolation from the Lesions. Absence of growth on ordinary agar when inoculated direct from the lesions. The isolation of the organism is rather difficult, as the organism does not grow at first on ordinary agar and various sugar agars; agar tubes inoculated with pus direct from the lesions do not show any growth; it grows on certain special media, the best apparently being creatinin and uric acid agar, but even on these special media the growth is very scanty at first. Later it can be trained to grow on practically all ordinary media, the best medium being Löffler's serum, but the growth is always scanty.

Creatinin Agar. On neutral creatinin agar the growth is fairly visible, though scanty; it somewhat resembles the delicate growth of certain streptococci on ordinary agar.

Uric Acid Agar. The organism grows on this medium, but more scantily than on creatinin agar.

Growth on Ordinary Media. While apparently the organism does not grow on ordinary media (agar and various sugar agars) when these are inoculated direct with material from the lesions, it grows on such media, though scantily, when transplanted from creatinin and uric acid agar—and it can then be made to grow indefinitely provided subculturing is carried out every 3 days; certain strains may die suddenly.

Glucose Agar. On acid glucose-agar, as a rule, there is no growth; on neutral 4% glucose agar a scanty growth of the organism may take place, but it is usually extremely poor.