The QuickFISH system is a novel molecular diagnostic system based on the patented PNA-FISH technology. The principle of the assay is a simple one, enhancing the well-known technique of Fluorescent In Situ Hybridisation (FISH) by incorporating the use of Peptide Nucleic Acids (PNA). Peptide Nucleic Acid (PNA) molecules are DNA mimics in which the negatively charged sugar phosphate backbone found in DNA and RNA is replaced with a non-charged polyamide or “peptide” backbone, while retaining the nucleotide bases that form the basis of the genetic code.
This means that a PNA molecule will hybridise according to the same base-pairing rules as any other nucleic acid. However, as the PNA molecule is unaffected by electrostatic repulsion between negatively charged backbones, it will bind more rapidly and specifically than a comparable DNA or RNA molecule. This means that probes composed of PNA can be shorter, and their hydrophobic backbone allows them to cross the cell membrane with ease.
The PNA-FISH technology uses these characteristics to allow pathogens to be identified quickly and accurately. By using PNA-FISH probes with a complementary sequence to the pathogen’s ribosomal RNA, a specific and sensitive reaction enables whole cell visualisation of the target pathogen(s) using fluorescence microscopy. The assay requires minimal sample preparation as cells don’t need to be lysed to isolate genetic material and generates visual results that match Gram-stain morphology.
The QuickFISH platform has brought further advances to this technique by eliminating the need for wash steps, reducing incubation times and simplifying the protocol. As a definitive pathogen identification can be obtained in 20 minutes, the QuickFISH technique is ideal for use in any clinical microbiology laboratory.
Unlike C.alibicans and C.paralopsilosis, many C.glabrata isolates are not sensitive to fluconazole: species identity is needed to help make the correct decisions on appropriate treatment.
QuickFISH: Candida allows clinicians to rapidly ensure early, appropriate antifungal therapy, facilitating better patient outcomes and reducing antifungal drug costs.
According to the Health Protection Agency, bacteraemias caused by Enterococcus species are the fourth most common type seen in NHS hospitals. The vast majority of these infections can be linked to two causative pathogens, Enterococcus faecalis and Enterococcus faecium.
QuickFish Enterococcus allows clinicians to rapidly ensure early, appropriate therapy for patients with E. faecium infections, while minimising the unnecessary use of broad spectrum antibiotics
Gram negative rods look identical under the light microscope after gram staining and further identification to species by culture methods can take 24-48 hours.
QuickFISH: Gram negative rods allows clinicians to rapidly ensure early, appropriate therapy for patients with Pseudomonas bacteraemia, while minimising the unnecessary use of aggressive and broad spectrum antibiotics.
Staphylococcus species look identical under the light microscope after gram staining, and further identification to species by culture methods can take 24-48 hours.
QuickFISH: Staphylococcus provides a positive, unambiguous species ID in 20 minutes, and is based on the proven, patented PNA-FISH technology from AdvanDX.