Clinical Microbiology Flashcards
Clinical Microbiologist
Isolate and identify microbes from clinical specimens rapidly.
Categories of Testing for a Suspected Infectious Agent
Rapid Tests and Immunoassays Molecular Tests Biochemical Tests Cultures Microscopy
Biosafety Levels
1: Standard practices, basic PPE.
4: BSL-3 practice plus; different clothing; shower to exit; decontamination; glove box work.
Direct Identification of Microbes
Growth/Biochemical Characteristics Microscopy Molecular Methods Bacteriophage Typing Immunologic Tests
Indirect Identification of Microbes
Serology
Immunofluoresence
Dichotomous Keys
Used for identification of bacteria following isolation. Series of choices narrow down the identity of a bacterial pathogen.
Rapid Identification Methods
STAPH-IDENT System, automated systems, immunologic systems.
Microscopy
Dark field for detection of spirochetes; fluorescence for detection of fungi. Often use stains (Gram, acid fast)
Monoclonal Ab
mAbs can be fluorescently labeled and used diagnostically because they can recognize a single epitope.
Immunofluorescence
Fluorescent dyes ca be coupled to antibodies and visualized directly (antibody directly attaches to target) or indirectly (labeled antibody attaches to non-labeled antibody which attaches to target).
Identification of Parasites
Via microscopy. Using histological staining of blood, negative staining of other fluids, or immunofluorescence staining.
Molecular Genetic Identification Methods
Accurate. Compares proteins or nucleic acids. i.e PCR, DNA hybridization, ribotyping (16s rRNA), genomic and plasmid fingerprinting.
Real-Time PCR
Detects, amplifies and quantifies a target DNA molecule.
Immunological Techniques
Detection of antigens or antibodies in a specimen. Useful when culturing is impractical, easy to use, rapid, sensitive, and specific. i.e. OraQuick kit detect HIV antibodies in saliva in 10 minutes.
Serotyping
Use of serum antibodies to detect and identify other molecules. Differentiates serotypes of microbes by analyzing antigenic composition. i.e. testing for cell wall antigens.
