Topic 8: Automated Identification System for Fungal Pathogens

1970s

Automated instruments were introduced into clinical microbiology laboratories in ...?

Time consuming, Operator Dependent, Lack Sensitivity, have a limited Database

Conventional methods once considered gold standard are...? [4]

Minute > Large

The ideal Automated System Should be able to handle Minute specimens, large database, versatile and can be regularly updated [If true write true, if False write the word that makes it False and write the correct word. separate with >]

True

The ideal Automated System should have clearly established cut off values for detection [If true write true, if False write the word that makes it False and write the correct word. separate with >]

Expensive > Inexpensive

The ideal Automated System has expensive reagents, high sensitivity, accuracy, reproducibility [If true write true, if False write the word that makes it False and write the correct word. separate with >]

True

The ideal Automated System is Easy to use [If true write true, if False write the word that makes it False and write the correct word. separate with >]

True

The ideal Automated System rapid, minimal turn around time [If true write true, if False write the word that makes it False and write the correct word. separate with >]

Qualitative > Quantitative

The ideal Automated System is Qualitative [If true write true, if False write the word that makes it False and write the correct word. separate with >]

True

The ideal Automated System can perform Resistance determination [If true write true, if False write the word that makes it False and write the correct word. separate with >]

True

The ideal Automated System can Handle different sample types [If true write true, if False write the word that makes it False and write the correct word. separate with >]

AUTOMATED IDENTIFICATION AND DETECTION SYSTEMS

Colorimetric based

Identify the detection system: Principle: using colorimetric technology to determine individual biochemical reactions for ease of identification

Colorimetric based

Identify the detection system: Commonly in card format

Colorimetric based

Identify the detection system: Requires Gram staining prior to performing test

Colorimetric based

Identify the detection system: limited to yeast species

Matrix-assisted laser desorption/ionization time of flight

Identify the detection system: The sample within the matrix is ionized with a laser beam. protonated ions are accelerated at a fixed potential, where these separate from each other on the basis of their mass-to-charge ratio. charged analytes are then detected and measured. Peptide Mass fingerprint is generated and compared to PMF in database

Bruker MS, Vitek MS

2 Main MALDI-TOF Systems that are commercially available

Bruker MS

Identify the MALDI-TOF System: 25 genera and 42 species of filamentous fungi (72% of clinical isolates)

Vitek MS

Identify the MALDI-TOF System: 32 genera and 81 species of filamentous fungi (66.8% of clinical isolates)

SARAMIS

Identify the MALDI-TOF System: New Brand. 45 genera, 168 species of filamentous fungi

Matrix-assisted laser desorption/ionization time of flight

Identify the detection system: Fast TAT, Reliable, Small sample only. No need for Gram staining. Database includes Yeasts and Filamentous Molds

Syndromic panel

Identify the detection system: Molecular assay, rapid detection, High sensitivity and Specificity

Syndromic panel

Identify the detection system: Cartridge form. expensive. Detection is limited to targets in the kit. Usually only common clinically isolated organisms are selected in the panels

infection of Physiologic system

Syndromic panel Kits are designed according to...?

T2 Magnetic Resonance

T2MR Full word

T2MR biosystem

Identify the detection system: Fully automated qualitative assay that combines nuclear magnetic and PCR molecular Assay to detect 5 Candida species from whole blood samples

T2MR biosystem

Identify the detection system: Superparamagnetic particles

T2MR biosystem

Identify the detection system: Detects and provides species-level identification by measuring magnetic resonance produced as a result of agglomeration of superparamagnetic particles

albicans, tropicalis, krusei, glabrata, parapsilosis

T2MR biosystem Detects Specifically...? [5] [no need to write genera]

parapsilosis, Orthoparapsilosis, and metapsilosis

T2MR biosystem Cannot differentiate parapsilosis complex specifically...? [3]

3 CFU/ml

T2MR biosystem Limit of detection for albicans and tropicalis

2 CFU/ml

T2MR biosystem Limit of detection for krusei and glabrata

1 CFU/ml

T2MR biosystem Limit of detection for parapsilosis

Multiplex PCR assays

Identify the detection system: Targets specific pathogens of interest, Not fully automated. Interpretation requires an experienced person in qPCR