Diagnosis of Bacterial Infections and Serology Methods

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What does serology focus on in diagnosing infections?

Microbial solid growth media

Cell-mediated immunity

Selective media

Detection of host immune response (correct)

In serology, how is antibody titer measured?

As the reciprocal of the highest dilution of serum that reacts positively in a specific test (correct)

As the type of microbial solid growth media used

As the energy source for bacterial growth

As the inhibitory compounds in bacterial growth

What does a fourfold rise of antibody titer in two serum samples taken 2 weeks apart indicate?

Use of differential media for diagnosis

Presence of inhibitory compounds in bacterial growth

Recent exposure to an infectious agent (correct)

Growth of bacteria on selective media

Which aspect is assessed through seroconversion in serology methods?

Detection of antibodies over time Signup and view all the answers

What is the main focus of measuring antibody titer in serology methods?

Detection of humoral immunity Signup and view all the answers

What does a titer of 1280 indicate in serology?

Positive result after diluting the serum 1:1280 Signup and view all the answers

What is the purpose of using selective media in microbiology?

To allow the growth of only certain bacteria while inhibiting the growth of others Signup and view all the answers

Which type of immune response involves immune cells that specifically recognize and clear infected host cells?

Cell-mediated immunity Signup and view all the answers

Which method is used for the biochemical characterization of bacterial isolates?

Fatty-acid characterization (GC) Signup and view all the answers

To successfully isolate bacteria, what must we provide the bacteria

All the above Signup and view all the answers

What is the term used to describe bacteria that have not been cultured on artificial media?

Unculturable bacteria Signup and view all the answers

In microbiology, what are the two general methods of methodology to aid in the diagnosis of bacterial infections?

A and B Signup and view all the answers

Which method is used for testing bovine tuberculosis (Mycobacterium bovis) and measures cell-mediated immunity?

Tuberculin skin test Signup and view all the answers

In the context of detecting intracellular infectious agents like certain bacteria and viruses, which type of immune response is essential for their elimination?

Cell-mediated immunity Signup and view all the answers

Which type of media promotes the growth of a specific microorganism by inhibiting the growth of others?

Selective media Signup and view all the answers

What is the most appropriate method for estimating bacterial numbers?

Gram-staining Signup and view all the answers

Which staining technique is specifically used for acid-fast bacteria like Mycobacterium?

Ziehl-Neelsen staining Signup and view all the answers

What is the FIRST and KEY step for accurate diagnostic testing of bacterial infections?

Proper specimen collection Signup and view all the answers

Which type of specimen collection method should be chosen based on factors like clinical symptoms, type of pathogen, and location of infection?

Selecting based on clinical symptoms, pathogen type, and infection location Signup and view all the answers

What are the two main methods for the direct detection of the bacteria

A and B Signup and view all the answers

Which phase of the diagnostic process involves the selection of appropriate methodology for processing and analysis of biospecimens?

A and C Signup and view all the answers

What other tests/cultures can be used as extra information for identifying a potential fastidious organism?

B and C Signup and view all the answers

What is the main purpose of differential media in microbiology?

To distinguish different bacterial groups based on their characteristics Signup and view all the answers

Which type of microbial solid growth media allows the growth of a large number of non-fastidious bacteria?

General-purpose media Signup and view all the answers

What are the inhibitory compounds commonly found in selective media for bacterial growth?

Bile salts and crystal violet Signup and view all the answers

Which of the following is considered an energy source for bacterial growth in solid media-- specifically for a Macconkey Agar.

A and C Signup and view all the answers

How do inhibitory compounds in solid media affect bacterial growth?

By largely inhibiting the growth of specific bacterial groups Signup and view all the answers

What is the purpose of MacConkey Agar?

To differentiate between lactose fermenting and non-lactose fermenting bacteria Signup and view all the answers

Why is Blood agar considered a differential medium?

To differentiate bacteria based on their hemolytic properties Signup and view all the answers

Why are incubation conditions crucial for bacterial growth in culture?

To create an optimal environment for bacterial growth Signup and view all the answers

Which type of solid media is routinely used for culturing routine samples?

All are routinely used. Signup and view all the answers

Why is Chocolate agar used for the culture of fastidious organisms?

To grow anaerobic bacteria Signup and view all the answers

What distinguishes selective media from general-purpose media?

Selective media contain inhibitory compounds against certain types of bacteria Signup and view all the answers

Why is it important for a diagnostic microbiology lab to use both selective and differential media?

To differentiate between pathogenic and non-pathogenic bacteria Signup and view all the answers

If a MacConkey Agar media displays a yellow, colorless colony, what type of bacteria is exhibited?

Non lactose fermenting bacteria Signup and view all the answers

What type of agar is a general purpose, enriched medium often used to grow fastidious organisms and to differentiate bacteria based on their hemolytic properties

Blood agar Signup and view all the answers

What are the two selections of methodology used in the detection of host immune responses?

Serology and Detection of cell mediated immunity Signup and view all the answers