Molecular epidemiology and characteristics of Corynebacterium diphtheriae and Corynebacterium ulcerans strains isolated in Italy during the 1990s

• Published in: Journal of medical microbiology Vol. 52; no. 2; pp. 181 - 188
• Main Authors: von Hunolstein, Christina, Alfarone, Giovanna, Scopetti, Franca, Pataracchia, Marco, La Valle, Roberto, Franchi, Fabio, Pacciani, Laila, Manera, Anna, Giammanco, Anna, Farinelli, Senia, Engler, Kathryn, De Zoysa, Aruni, Efstratiou, Androulla
• Format: Journal Article
• Language: English
• Published: Reading Soc General Microbiol 01-02-2003; Society for General Microbiology
• Subjects: Bacteriology; Biological and medical sciences; Colony Count, Microbial; Corynebacterium - classification; Corynebacterium - drug effects; Corynebacterium - genetics; Corynebacterium diphtheriae - classification; Corynebacterium diphtheriae - drug effects; Corynebacterium diphtheriae - genetics; Corynebacterium Infections - epidemiology; Corynebacterium Infections - microbiology; Diphtheria - epidemiology; Diphtheria - microbiology; Dose-Response Relationship, Drug; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Fundamental and applied biological sciences. Psychology; Genetics; Humans; Italy - epidemiology; Microbial Sensitivity Tests; Microbiology; Molecular Epidemiology; Polymerase Chain Reaction; Ribotyping; Virulence - genetics; Italy; Europe; Human; Ribotype; Molecular epidemiology; Bacteria; Genotype; Actinomycetes; Corynebacteriaceae; Corynebacterium diphtheriae; Clinical isolate
• ISSN: 0022-2615; 1473-5644
• DOI: 10.1099/jmm.0.04864-0

1 Laboratorio di Batteriologia e Micologia Medica, Istituto Superiore di Sanitá, Roma, Italy 2 Unitá Ospedaliera Malattie Infettive, Azienda Ospedaliera, Trieste, Italy 3 Unitá Organizzativa Microbiologia, Ospedale San Giacomo, Roma, Italy 4 Laboratorio di Analisi Chimico-Cliniche e Microbiologiche, Ospedale G. Eastman, Roma, Italy 5 Universitá degli Studi di Palermo, Palermo, Italy 6 Universitá degli Studi di Perugia, Perugia, Italy 7 Respiratory and Systemic Infection Laboratory, PHLS Central Public Health Laboratory, London, UK
Correspondence Christina von Hunolstein cris.v.h{at}iss.it
Received 2 January 2002 Accepted 25 September 2002
Five cases of diphtheria were reported in Italy between January 1990 and June 2001. Three cases were confirmed microbiologically by the isolation of toxigenic Corynebacterium diphtheriae (two cases) and Corynebacterium ulcerans (one case). Over the same period, 11 cases of non-toxigenic C . diphtheriae infection were reported to the Italian Public Health Institute, from which the causative organism was isolated from a skin infection in one case and from the throat in the other ten. Seven of the throat isolates were associated with fever, severe pharyngitis and tonsillitis and were all biotype gravis . Because there are no standardized breakpoints, the antimicrobial sensitivities of C. diphtheriae were determined in accordance with the National Committee for Clinical Laboratory Standards guidelines for Streptococcus spp. other than Streptococcus pneumoniae . MICs for penicillin ranged between 0.125 and 0.250 mg l - 1 and 7 out of 11 strains had a minimal bactericidal concentration (MBC)/MIC ratio 32. All strains were sensitive to clindamycin (MIC 0.25 mg l - 1 ), rifampicin (MIC 1 mg l - 1 ) and tetracycline (MIC 2 mg l - 1 ), and showed moderate susceptibility to cefotaxime (MIC 0.75 – 1.5 mg l - 1 ). Molecular typing (ribotyping) demonstrated the presence of several distinct ribotypes. The ribotype designated ‘D11’ has been documented amongst strains isolated in the UK, Russia, Germany, Romania and Sweden. Ribotype ‘D75’ has only been documented in the UK. The C. ulcerans strain had a ribotype pattern identical to that found in recent isolates from the UK.