TABLE 3.
Summary of findings from the present study and from previous studies reporting SCCmec fragments in methicillin-susceptible S. aureus
| No. of MSSA isolates with SCCmec regions (source)a | Method used to detect SCCmec segments (reference) | SCCmec segments found (nb) | MLST/spa genotype (nb) | Further analysis of SCCmec-associated sequences undertaken | Reference |
|---|---|---|---|---|---|
| 7 (four Irish hospitals) | PCR to detect mec complexes A, B, and C (32) | ccrAB2c (2); | ST8/t190 (4) | Present study | |
| PCR to detect ccrAB1 to-4, ccrC (32) | ccrAB4c (6) | ST8/t3209 (1) | Yese | ||
| Multiplex PCR (47) | mecIc (2); dcsc (3) | ST5/t088 (2) | |||
| 2 (i.v. drug users) | PCR to detect ccrAB1 (28) | ccrAB1c | Not done | No | 6 |
| Multiplex PCR (47) | dcsc | ||||
| 26 (regions worldwide) | Real-time PCR (IDI-MRSA assay) to amplify the right SCCmec/orfX junction | Right SCCmec/orfX junctiond | Not done | No | 25 |
| PCR detection of mecA (39) | |||||
| 6 (French hospitals) | PCR detection of ccrAB1, ccrAB2, and ccrAB3 (36) | IS431-pUB110, dcs | ST8/t008 (1) | No | 13 |
| Multiplex PCR (47) | IS431-pUB110-IS431-dcs | ||||
| PCR detection of HVR-IS431-pUB110-IS431-dcs-orfX | |||||
| 1 (nasal swab, HCW) | Real-time PCR (Genotype MRSA Direct) to amplify right SCCmec/orfX junction | Right SCCmec/orfX junctionc | t498 | No | 57 |
| PCR to confirm the right SCCmec/orfX junction (7) | |||||
| PCR detection of mecA (50) | |||||
| PCR to detect ccrAB1, ccrAB2, and ccrAB3 (46) | |||||
| 169 (60 French hospitals) | Real-time PCR (IDI-MRSA assay) to amplify the right SCCmec/orfX junction | Right SCCmec/orfX junction | ST8/t008 (isolate 1) | No | 11 |
| PCR to investigate HVR-IS431-pUB110-IS431-dcs-orfX (13) (2 isolates only investigated) | dcs only (isolate 1) | ST8/t024 (isolate 2) | |||
| PCR to detect ccrAB1, ccrAB2, and ccrAB3 (28) (14 isolates investigated) | HVR-IS431-pUB110-IS431-dcs (isolate 2) |
a
HCW, health care worker; i.v., intravenous.
b
n, no. of isolates.
c
Identity of amplimer(s) confirmed by DNA sequencing.
d
IDI-MRSA assay amplimer identity was confirmed by conventional endpoint PCR.
e
A 26-kb SCCmec remnant was sequenced from one ST8/t190 isolate, and ccrAB4 was found to be located 5,549 bp upstream of SCCmec.