The genusDietzia: a new home for some known and emerging opportunist pathogens

Abstract

The genus Dietzia has only been established fairly recently. The Gram morphology and colony appearance of the species of this genus is remarkably similar to Rhodococcus equi. In the absence of simple, accurate methods for their identification, Dietzia spp. might have been misidentified as a Rhodococcus spp. and/or considered to be contaminants only. This MiniReview is designed to summarize current evidence on the clinical significance of Dietzia species, to consider their potential role as human pathogens, and to outline approaches that can be used to accurately classify and identify members of the genus, with the overall aim of alerting the medical microbiological community to a little known genus that contains clinically significant organisms.

First Isolation of Dietzia cinnamea from a Dog Bite Wound in an Adult Patient

“…Furthermore, in clinical samples, Dietzia spp. can be reliably differentiated from members of other mycolic acid-containing genera by using 16S rRNA gene sequencing analysis (8,11,13). Although the potential of D. cinnamea to cause an infection was not able to be shown in our study, as an effective antimicrobial treatment was introduced without delay, previous reports by other authors suggest that Dietzia species have the potential to act as opportunistic pathogens (1,7,12,13,19).…”

“…as Rhodococcus spp. This may explain why only a few cases of Dietzia species isolations from human sources have been reported, although members of this genus are widely distributed in diverse habitats, such as marine, soil, and even hospital environments (2,3,8,10,11,19). Recently, some additional phenotypic tests have been reported to help distinguish Dietzia spp.…”

Discovery of a cell wall porin in the mycolic‐acid‐containing actinomycete Dietzia marisDSM 43672

“…Dietzia sp. are only rarely reported as pathogens although they may often be misidentified, notably as rhodococci [2,8].…”

“…maris belongs to the mycolata, a widespread group of mycolic-acid-containing actinomycetes [2,4,9]. These bacteria produce cell walls of a unique structure with low permeability that contain large amounts of lipids on top of the peptidoglycan layer in the form of two-branched, 3-hydroxylated fatty acids, the mycolic acids.…”

“…This genus has now been placed into the family Dietziaceae within the suborder Corynebacterineae of the Actinomycetales [2,3]. Dietzia maris is a Gram-positive, aerobic, non-sporeforming soil bacterium which forms cocci that can develop into short rods [4].…”