Bacteriological Properties of a Sucrose-Fermenting Corynebacterium diphtheriae Strain Isolated from a Case of Endocarditis

Abstract

An atypical sucrose-fermenting Corynebacterium diphtheriae strain was isolated from three blood cultures of a 14-year-old girl presented to a university teaching hospital in Rio de Janeiro, Brazil. She had mitral endocarditis that proved to be fatal despite intensive antibiotic therapy. Blood cultures showed a fluorescent Gram-positive, aerobic, coryneform-like bacillus presenting pyrazinamidase and CAMP reaction negative. The isolate was identified as a toxigenic strain of C. diphtheriae var. mitis by both Elek and radial immunodiffusion (RID) tests. The invasive C. diphtheriae sucrose-fermenting biotype strain adhered to glass surfaces and expressed pronounced hemagglutinating activity (titer 8), a property common among the nonfermenting biotype strains. Laboratories should be alert to the possibility of the isolation of C. diphtheriae with a positive sucrose fermentation test, especially when nontoxigenic strains are isolated from uncommon anatomic sites.

Nondiphtherial Corynebacterium species isolated from clinical specimens of patients in a university hospital, Rio de Janeiro, Brazil

“…Infections caused by these organisms are emerging, new species are been recognized, and infections by toxigenic and nontoxigenic C. diphtheriae strains are also being described with increasing frequency, indeed, in countries were diphtheria have been totally or almost eradicated (16,17,18). However, this renewed interest has not been followed by an in depth study to determine the antimicrobial susceptibility of such organisms.…”

“…The scheme used for identification of Corynebacterium sp. was based on biochemical tests used by different authors (4,10,11,12,17): morphology, pigmentation and hemolysis production of colonies, Gram stain morphology, catalase and nitrate reaction, motility, lipid requirement, urease, DNAse and pyrazinamidase (PYZ) production, esculin and gelatin hydrolysis, CAMP reaction and acid production from glucose, maltose, sucrose, xylose, mannose, fructose mannitol, trehalose, galactose and arabinose.…”

Invasion of endothelial cells and arthritogenic potential of endocarditis-associated Corynebacterium diphtheriae

“…Although some C. diphtheriae strains seem to have a preference for attaching to vascular endothelium, microorganisms (HC01 and HC02 strains) that have caused invasive blood-born infection also differed in their potential to infect HUVECs: the HC01 strain was found to be more adherent and invasive to HUVECs than the HC02 strain. This fact may help to explain the aggressive nature of the disease leading to death or valve replacement in patients with endocarditis despite antimicrobial therapy in many instances, including in cases related with HC01 and HC02 strains, respectively (Mattos-Guaraldi & Formiga, 1998;Belko et al, 2000).…”

“…Furthermore, C. diphtheriae is not only the aetiological agent of diphtheria, but can cause other infections as well (Ott et al, 2010). Systemic infections caused by C. diphtheriae (Patey et al, 1997;Mattos-Guaraldi & Formiga, 1998) suggest that diphtheria bacilli are able to penetrate respiratory epithelial cells and gain access to deeper tissues (Mattos-Guaraldi & Formiga, 1998;Hirata et al, 2004). Bacteraemia and endocarditis caused by both non-toxigenic and toxigenic C. diphtheriae strains have been reported with increased frequency (Hirata et al, 2004;Bertuccini et al, 2004).…”

Potential pathogenic role of aggregative- adhering Corynebacterium diphtheriae of different clonal groups in endocarditis

“…Infective endocarditis due to C. diphtheriae is perhaps more common than supposed and on occasion may be an aggressive fatal disease (3). Few reports have dealt with the microbiological aspects of community-acquired endocarditis caused Corynebacterium diphtheriae and endocarditis www.bjournal.com.br by C. diphtheriae (4)(5)(6). Entry of C. diphtheriae by invasive processes was described as being caused by percutaneous trauma, skin (7,8) and throat colonization (9).…”