Diagnosis of infectious endocarditis in patients undergoing valve surgery.
OBJECTIVE
Histologic examination of valve samples is considered as the gold standard for the diagnosis of infectious endocarditis. Molecular tools are also very promising for patients with negative-culture endocarditis. Thus, we studied the contribution of valvular histology, culture, and 16S rRNA PCR amplification plus sequencing to the diagnosis of infectious endocarditis in patients undergoing valve surgery.


METHODS
We performed culture, histological examination, and broad-range PCR amplification plus sequencing on valve samples taken from 127 patients with infectious endocarditis and from 118 patients without endocarditis. The sensitivity and specificity of these tests for the diagnosis of endocarditis in patients undergoing valve surgery were studied.


RESULTS
The sensitivity of PCR was of 61% (64/105) whereas that of histological examination was of 63% (62/98) and that of valve culture was of only 13% (14/105). All 68 positive PCR results considered reliable according to an interpretation scheme were from patients with infectious endocarditis, resulting in a 100% (118/118) specificity of the interpreted molecular approach. The specificity of histology was also of 100% (118/118) when using stringent criteria (ie, presence of vegetation, microorganisms, and/or valvular inflammation with mainly polymorphonuclear cells). PCR identified an etiological agent in 38% (5/13) of definite blood culture-negative infectious endocarditis.


CONCLUSIONS
We show that valvular histology with stringent criteria is the gold standard for the diagnosis of infectious endocarditis. Broad-range amplification of 16S rRNA gene is indicated for infectious endocarditis of unknown etiology, whereas valve culture is of limited sensitivity.
Greub
Gilbert
G
Unité des Rickettsies, Faculté de Médecine, Université de la Méditerranée, Marseille, France.
Lepidi
Hubert
H
Rovery
Clarisse
C
Casalta
Jean-Paul
JP
Habib
Gilbert
G
Collard
Frédéric
F
Fournier
Pierre-Edouard
PE
Raoult
Didier
D
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D016009:Chi-Square Distribution; D004269:DNA, Bacterial / Q000032:analysis; D004697:Endocarditis, Bacterial / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D005260:Female; D006351:Heart Valves / Q000382:microbiology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric
D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S