title: Microbiological and molecular characterization of Corynebacterium diphtheriae isolated in Algeria between 1992 and 2015.
abstract: The objectives of this study were to undertake the microbiological and molecular characterization of Corynebacterium diphtheriae isolates collected in Algeria during epidemic and post-epidemic periods between 1992 and 2015. Microbiological characterization includes the determination of biotype and toxigenicity status using phenotypic and genotypic methods. Antimicrobial susceptibility was determined by the E-test method. Molecular characterization was performed by multi-locus sequence typing. In total, there were 157 cases of C. diphtheriae isolates, 127 in patients with respiratory diphtheria and 30 with ozena. Isolates with a mitis biotype were predominant (122 out of 157; 77.7%) followed by belfanti (28 out of 157; 17.8%) and gravis biotype (seven out of 157; 4.5%). Toxigenic isolates were predominant in the period 1992-2006 (74 out of 134) whereas in the period 2007-2015, only non-toxigenic isolates circulated (23 out of 23). All 157 isolates were susceptible to erythromycin, gentamicin, vancomycin and cotrimoxazole. Reduced susceptibility to penicillin G, cefotaxime, tetracycline and chloramphenicol was detected in 90 (57.3%), 88 (56.1%), 112 (71.3%) and 90 (57.3%) isolates, respectively. Multi-locus sequence typing analysis indicates that sequence type 116 (ST-116) was the most frequent, with 65 out of 100 isolates analysed, in particular during the epidemic period 1992-1999 (57 out of 65 isolates). In the post-epidemic period, 2000-2015, 13 different sequence types were isolated. All belfanti isolates (ten out of 100 isolates) belonged to closely related sequence types grouped in a phylogenetically distinct eBurst group and were collected exclusively in ozena cases. In conclusion, the epidemic period was associated with ST-116 while the post-epidemic period was characterized by more diversity. Belfanti isolates are grouped in a phylogenetically distinct clonal complex.
authors: Medical Bacteriology Laboratory, Institut Pasteur, Algiers, Algeria. Electronic address: n_benamrouche@yahoo.fr.
authors: N
authors: N
authors: Benamrouche
authors: Medical Bacteriology Laboratory, Institut Pasteur, Algiers, Algeria.
authors: S
authors: S
authors: Hasnaoui
authors: Molecular Prevention and Therapy of Human Diseases Unit, Institut Pasteur, Paris, France.
authors: E
authors: E
authors: Badell
authors: Medical Bacteriology Laboratory, Institut Pasteur, Algiers, Algeria.
authors: B
authors: B
authors: Guettou
authors: Medical Bacteriology Laboratory, Institut Pasteur, Algiers, Algeria.
authors: M
authors: M
authors: Lazri
authors: Molecular Prevention and Therapy of Human Diseases Unit, Institut Pasteur, Paris, France.
authors: N
authors: N
authors: Guiso
authors: Medical Bacteriology Laboratory, Institut Pasteur, Algiers, Algeria.
authors: K
authors: K
authors: Rahal
mesh_terms: D000328:Adult; D000462:Algeria / Q000453:epidemiology; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002439:Cefotaxime / Q000627:therapeutic use; D002701:Chloramphenicol / Q000627:therapeutic use; D003353:Corynebacterium diphtheriae / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification*; D004165:Diphtheria / Q000188:drug therapy / Q000453:epidemiology*; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D004917:Erythromycin / Q000627:therapeutic use; D005260:Female; D060005:Genotyping Techniques; D005839:Gentamicins / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D058885:Multilocus Sequence Typing; D010400:Penicillin G / Q000627:therapeutic use; D010802:Phylogeny; D012222:Rhinitis, Atrophic / Q000188:drug therapy / Q000453:epidemiology*; D013752:Tetracycline / Q000627:therapeutic use; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000627:therapeutic use; D014640:Vancomycin / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins; D004917:Erythromycin; D002701:Chloramphenicol; D014640:Vancomycin; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D013752:Tetracycline; D002439:Cefotaxime; D010400:Penicillin G
keywords: Algeria; Antimicrobial susceptibility; Biotype; Corynebacterium diphtheriae; MLST; Toxin