1
|
Chebbi Y, Frigui S, Raddaoui A, Belloumi D, Lakhal A, Torjemane L, Ben Abeljelil N, Ladeb S, Ben Othmen T, El Fatmi R, Achour W. Coagulase negative Staphylococcus bacteremia in hematopoietic stem cell transplant recipients: Clinical features and molecular characterization. Acta Microbiol Immunol Hung 2021; 68:73-79. [PMID: 33999858 DOI: 10.1556/030.2021.01315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 10/09/2020] [Indexed: 11/19/2022]
Abstract
The purpose of our study was to investigate the epidemiology of coagulase negative staphylococci (CoNS) responsible for bacteremia in hematopoietic stem cell transplant (HSCT) recipients and to determine the prevalence and the genetic background of methicillin resistance. The prevalence of CoNS bacteremia was 7.4% (54/728), higher in allograft (10.7%) than in autograft (4.7%) recipients. A sepsis or a septic shock were observed in 9% of cases. No deaths were attributable to CoNS bacteremia. The methicillin resistance rate was 81%. All MR-CoNS, harbored mecA gene and 90% were typeable with SCCmec typing using PCR amplification. The SCCmec type IV was the most frequent (44%). Clonal dissemination of MR- Staphylococcus epidermidis strains was limited. Our study showed a low prevalence and favorable outcome of CoNS bacteremia in HSCT recipients with limited clonal diffusion. However, they were associated with a significant rate of severe infections and a high rate of methicillin resistance, mediated by SCCmec IV element in most cases.
Collapse
Affiliation(s)
- Yosra Chebbi
- 1Laboratory Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
- 2Tunis El Manar University, Faculty of Medicine of Tunis, LR18ES39, 1006, Tunis, Tunisia
| | - Siwar Frigui
- 1Laboratory Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
- 2Tunis El Manar University, Faculty of Medicine of Tunis, LR18ES39, 1006, Tunis, Tunisia
| | - Anis Raddaoui
- 1Laboratory Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
- 2Tunis El Manar University, Faculty of Medicine of Tunis, LR18ES39, 1006, Tunis, Tunisia
| | - Dorra Belloumi
- 3Hematology Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
| | - Amel Lakhal
- 3Hematology Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
| | - Lamia Torjemane
- 3Hematology Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
| | - Nour Ben Abeljelil
- 3Hematology Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
| | - Saloua Ladeb
- 3Hematology Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
| | - Tarek Ben Othmen
- 3Hematology Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
| | - Rym El Fatmi
- 3Hematology Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
| | - Wafa Achour
- 1Laboratory Ward, National Bone Marrow Transplant Center, 1006, Tunis, Tunisia
- 2Tunis El Manar University, Faculty of Medicine of Tunis, LR18ES39, 1006, Tunis, Tunisia
| |
Collapse
|
2
|
Abbassi MS, Bouchami O, Touati A, Achour W, Ben Hassen A. Clonality and occurrence of genes encoding antibiotic resistance and biofilm in methicillin-resistant Staphylococcus epidermidis strains isolated from catheters and bacteremia in neutropenic patients. Curr Microbiol 2008; 57:442-8. [PMID: 18769853 DOI: 10.1007/s00284-008-9227-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2008] [Accepted: 06/10/2008] [Indexed: 10/21/2022]
Abstract
Thirty methicillin-resistant Staphylococcus epidermidis strains isolated from catheters and blood cultures from neutropenic patients were studied. They were classified into 17 multidrug-resistance patterns. Polymerase cahin reaction analysis revealed that methicillin resistance was encoded by the mecA gene in all strains, and aminoglycosides resistance was due to aac(6')-Ie-aph(2'')-Ia (23 strains), ant(4')-Ia (13), and aph(3')-IIIa (1) genes. The aac(6')-Ie-aph(2'')-Ia gene was detected concomitantly with aph(3')-IIIa, and ant(4')-Ia genes in one and nine strains, respectively. Erythromycin resistance was encoded by the ermC (11 strains), ermA (6), and msrA (2) genes. The ermC gene was inducibly expressed in five strains, whereas the ermA was exclusively constitutively expressed. The icaA and icaC genes were detected in 19 strains; however, biofilm production was observed in only 16 strains. Most strains harbored multiple plasmids of variable sizes ranging from 2.2 to 70 kb, and two strains were plasmid-free. PFGE identified 15 distinct PFGE types, and five predominant genotypes were found. Our study showed the occurrence of complex genetic phenomenons. In unrelated strains, evidence of horizontal transfer of antibiotic-encoding genes and/or ica operon, and in indistinguishable strains, there is a quite good likelihood of independent steps of loss and/or gain of these genes. This genome dynamicity might have enhanced the invasiveness power of these methicillin-resistant S epidermidis strains.
Collapse
Affiliation(s)
- Mohamed Salah Abbassi
- Laboratory of the National Bone Marrow Transplantation Centre, Street Djebel-Lakdhar, Bab-Saadoun, 1006, Tunis, Tunisia
| | | | | | | | | |
Collapse
|
3
|
Achour W, Bouchami O, Galopin S, Leclercq R, Ben Hassen A. Analysis of pristinamycin-resistant Staphylococcus epidermidis isolates in the Tunisian Bone Marrow Transplant Center. Lett Appl Microbiol 2008; 46:358-63. [PMID: 18194160 DOI: 10.1111/j.1472-765x.2007.02318.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS We report the analysis of genetic determinants conferring resistance to pristinamycin in Staphylococcus epidermidis strains and epidemiology typing of these strains by pulsed-field gel electrophoresis. METHODS AND RESULTS Staphylococcus epidermidis (346 isolates) were searched for strains with pristinamycin resistance. Pristinamycin-resistant strains (seven isolates) were isolated in five patients with haematological cancer in the Bone Marrow Transplant Centre of Tunisia in 2002. Resistance to pristinamycin was observed in 2% of isolates. The seven pristinamycin-resistant strains shared resistance to oxacillin (MIC = 8-512 microg ml(-1)), gentamicin (MIC = 16-512 microg ml(-1)), erythromycin (MIC > 1024 microg ml(-1)), lincomycin (MIC > 1024 microg ml(-1)), pristinamycin (MIC = 4-16 microg ml(-1)) and rifampin (MIC = 128-256 microg ml(-1)). erm genes were amplified: ermA from six strains and ermC from one. vga gene encoding streptogramins A resistance (pristinamycin résistance) was amplified from all strains and typed as vgaA by analysis after electrophoresis of restriction profiles of vga amplicons (two fragments with Sau3A of 164 and 378 bp; one fragment with EcoRI). Pulsed-field gel electrophoresis (PFGE) of SmaI chromosomal DNA digests of the seven S. epidermidis isolates divided them into two distinct pattern types: pulsed-field type A (classified from A1 to A6 subtypes) and type B. The six strains harbouring ermA genes belonged to the PFGE type A while the strain harbouring ermC genes belonged to the PFGE type B. We characterized an epidemic strain carrying the vgaA and ermA genes responsible for the outbreak. CONCLUSIONS Two clones of pristinamycin-resistant S. epidermidis were isolated in our patients. One of them, isolated in all patients, had expanded over six months suggesting acquisition by cross-contamination. SIGNIFICANCE AND IMPACT OF THE STUDY Increasing isolation of pristinamycin resistant S. epidermidis strains is an alarming indicator of nosocomial dissemination. The vector will be determined to establish a system of epidemiological surveillance.
Collapse
Affiliation(s)
- W Achour
- Laboratoire du Centre National de Greffe de Moelle Osseuse, Tunis, Tunisia
| | | | | | | | | |
Collapse
|