Corynebacterium jeikeium is a rod-shaped, catalase-positive, aerobic species of Actinomycetota in the genus Corynebacterium.

C. jeikeium is pathogenic, typically causing an opportunistic infection seen most frequently in bone marrow transplant patients.

C. jeikeium is a strictly aerobic organism and forms tiny grayish white colonies when grown on blood agar.

[2] C. jeikeium is usually susceptible to vancomycin and tetracycline.

Resistance to macrolide antibiotics is often encountered.