Rapid detection of Staphylococcus aureus Panton-Valentine leukocidin in clinical specimens by enzyme-linked immunosorbent assay and immunochromatographic tests.
Staphylococcus aureus strains producing Panton-Valentine leukocidin (PVL) have been epidemiologically linked to specific human infections. To evaluate immunological tests that may be used to diagnose infections with PVL-producing strains, we prospectively collected pus, respiratory tract specimens, and joint fluid specimens from which S. aureus had been isolated in clinical laboratories in six countries. An enzyme-linked immunosorbent assay (ELISA) and an immunochromatographic test (ICT) targeting LukS-PV were performed directly with clinical samples for the detection of PVL. The same tests were applied to S. aureus culture supernatants. The corresponding S. aureus isolates were characterized by PCR for the presence of the PVL locus (lukS-PV and lukF-PV) and the mecA gene. A total of 185 samples from 144 skin infections, 23 bone and joint infections, and 18 lower respiratory tract infections were analyzed. By PCR, 72/185 S. aureus isolates were PVL locus positive (PVL(+)); 28 of these were also mecA positive. PVL was detected in the supernatants of all PVL(+) strains by both ELISA and an ICT, while no signal was observed with PVL-negative strains. The PVL concentrations in human clinical samples that grew PVL(+) strains ranged from 0 to 399 microg/ml by ELISA. By the use of 0.015 microg/ml of PVL as a cutoff value, PVL was detected in 65/72 (90%) of the clinical samples by ELISA. The sensitivity and specificity of the ELISA test were 90% and 100%, respectively. By the ICT, PVL was detected in 57/72 (79%) of the samples, and the sensitivity and specificity of ICT were 79% and 100%, respectively. PVL is expressed by S. aureus during human infection, and a PVL-specific ELISA and ICT could be reliable tests for the diagnosis of infections caused by PVL-producing strains.
Université Lyon 1, Centre National de Référence des Staphylocoques, Lyon.
Cedric
C
Badiou
Oana
O
Dumitrescu
Narelle
N
George
Andrea R N
AR
Forbes
Eleanna
E
Drougka
Kian Sing
KS
Chan
Nadjia
N
Ramdani-Bouguessa
Helene
H
Meugnier
Michele
M
Bes
Francois
F
Vandenesch
Jerome
J
Etienne
Li Yang
LY
Hsu
Mohamed
M
Tazir
Iris
I
Spiliopoulou
Graeme R
GR
Nimmo
Kristina G
KG
Hulten
Gerard
G
Lina
D001426:Bacterial Proteins / Q000032:analysis* / Q000235:genetics; D001427:Bacterial Toxins / Q000032:analysis* / Q000235:genetics; D001431:Bacteriological Techniques / Q000379:methods*; D004269:DNA, Bacterial / Q000235:genetics; D005098:Exotoxins / Q000032:analysis* / Q000235:genetics; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007956:Leukocidins / Q000032:analysis* / Q000235:genetics; D046915:Penicillin-Binding Proteins; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013203:Staphylococcal Infections / Q000175:diagnosis* / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000737:chemistry* / Q000302:isolation & purification / Q000472:pathogenicity; D037521:Virulence Factors / Q000032:analysis* / Q000235:genetics
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin; D046915:Penicillin-Binding Proteins; D037521:Virulence Factors; C487789:mecA protein, Staphylococcus aureus