Evaluation of the peptide nucleic acid fluorescence in situ hybridisation technology for yeast identification directly from positive blood cultures: an Italian experience.
Fungaemia is an increasing nosocomial pathology. The 'gold standard' for detection of fungaemia is blood culture, but it is time-consuming and its sensitivity for early detection is low. On the other hand, yeasts present different antifungal sensitivity patterns to be quickly detected to allow an effective treatment. The aim of this study was to evaluate the diagnostic performances of PNA-FISH to directly identify yeasts from blood cultures and to compare results with those obtained by culture. A total of 176 blood cultures positive for yeasts at direct Gram stain and 24 negative blood cultures as control collected from 15 Italian hospitals, included in a network coordinated by the Medical Mycology Committee, Italian Society of Clinical Microbiology (AMCLI), were examined both by culture and PNA-FISH technology. Sensitivity of the PNA-FISH technique evaluated for five Candida species was 99.3% and specificity, 100%. Distinguishing which yeast is implicated in fungaemia and whether the infection is caused by multiple species are important for the selection of antifungal therapy. The PNA-FISH technique is a very useful approach because the test discriminates between groups of Candida species with different susceptibility pattern, particularly against azoles and echinocandins, with only a 90-minute turn-around time after the Gram-stain reading.
Microbiology Institute, AO, Ospedale San Carlo Borromeo, Milano, Italy. farina.claudio@sancarlo.mi.it
Claudio
C
Farina
Silvana
S
Perin
Stefano
S
Andreoni
Marco
M
Conte
Paolo
P
Fazii
Gianluigi
G
Lombardi
Esther
E
Manso
Cristina
C
Morazzoni
Silvana
S
Sanna
D001769:Blood / Q000382:microbiology; D016469:Fungemia / Q000382:microbiology*; D005658:Fungi / Q000145:classification* / Q000302:isolation & purification*; D006761:Hospitals; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D007558:Italy; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D009172:Mycology / Q000379:methods*; D020135:Peptide Nucleic Acids; D012680:Sensitivity and Specificity; D013997:Time Factors
D020135:Peptide Nucleic Acids