Corynebacterium urealyticum, formerly known as coryneform CDC group D2, was first recognized to be involved in human
infections 30 years ago. It is a slow-growing, lipophilic, asaccharolytic and usually multidrug-resistant organism with potent
urease activity. Its cell wall
peptidoglycan,
menaquinone, mycolic and cellular
fatty acid composition is consistent with that of the genus Corynebacterium.
DNA-
DNA hybridization studies and 16S
rDNA sequencing analysis have been used to determine the degree of relatedness of C. urealyticum to other corynebacterial species. The genome of the type strain consists of a circular chromosome with a size of 2 369 219 bp and a mean G + C content of 64.2%, and analysis of its genome explains the bacterium's lifestyle. C. urealyticum is a common skin colonizer of hospitalized elderly individuals who are receiving broad-spectrum
antibiotics. It is an opportunistic pathogen causing mainly acute
cystitis,
pyelonephritis, encrusted
cystitis, and encrusted
pyelitis. More infrequently, it causes other
infections, but mainly in patients with
urological diseases.
Infections are more common in males than in females, and treatment requires administration of
antibiotics active against the organism in vitro, mainly
glycopeptides, as well as surgical intervention, the latter mostly in cases of
chronic infection. Mortality directly associated with
infection by this organism is not frequent, but encrusted
pyelitis in kidney-recipient patients may cause graft loss. The outcome of
infection by this organism is reasonably good if the microbiological diagnosis is made and patients are treated appropriately.