Lancefield Classification Quiz

Play an AI-generated podcast conversation about this lesson

Which method can be used to extract the C carbohydrate from the streptococcal cell wall according to Rebecca Lancefield's findings?

Heating the organisms in the presence of oxygen

Placing organisms in a hypertonic solution

Boiling the organisms in water

Placing organisms in dilute acid and heating (correct)

What is the main function of M Protein in Streptococcus pyogenes?

Resisting phagocytosis (correct)

Promoting phagocytosis

Activating complement pathways

Stimulating antibody production

What is the role of Lipoteichoic Acid in Streptococcus pyogenes?

Adhesion to epithelial cells (correct)

Preventing recognition by antibodies

Promoting phagocytosis

Deactivating M Protein for virulence

Which Streptococcal strain is known to have over 200 serotypes?

Streptococcus pyogenes Signup and view all the answers

Which molecule helps prevent recognition of Streptococcus pyogenes by masking antigens?

Hyaluronic Acid Capsule Signup and view all the answers

What is the significance of M1 in Streptococcus pyogenes infections?

Resisting phagocytosis Signup and view all the answers

What is the difference between Streptolysin O and Streptolysin S?

Streptolysin O causes hemolysis without oxygen and is immunogenic, while Streptolysin S causes hemolysis with oxygen and is non-immunogenic. Signup and view all the answers

What is the most common type of Deoxyribonuclease (DNase) produced by Streptococcus pyogenes?

DNase B Signup and view all the answers

Which of the following is NOT a characteristic of erysipelas caused by Streptococcus pyogenes?

Seen in adults Signup and view all the answers

What is the role of Streptokinase produced by Streptococcus pyogenes?

It causes lysis of fibrin clots. Signup and view all the answers

Which of the following is NOT an Erythrogenic Exotoxin produced by Streptococcus pyogenes?

SpeD Signup and view all the answers

What is the most common manifestation of Streptococcus pyogenes infection?

Bacterial pharyngitis Signup and view all the answers

Which streptolysin is immunogenic but destroyed by skin fat?

Streptolysin O Signup and view all the answers

Which infection involves rapid progression of inflammation and necrosis known as 'galloping gangrene'?

Necrotizing Fasciitis Signup and view all the answers

Which Streptococcal infection leads to a life-threatening Toxic Shock Syndrome similar to Staphylococcal TSS?

Streptococcal Toxic Shock Syndrome Signup and view all the answers

What is the main symptom of Acute Glomerulonephritis that distinguishes it from other conditions?

Proteinuria Signup and view all the answers

What is the main factor causing Rheumatic Fever?

Antigenic Cross Reactivity with heart tissue Signup and view all the answers

Why is Gram stain of little value in microscopy for the mentioned infections?

Cells are resistant to drying Signup and view all the answers

What is the most common cause of pneumonia in 2-year-olds?

Pneumonia Signup and view all the answers

Which of the following is a characteristic of the $eta$-hemolytic pattern for Group B Streptococcus?

Bacitracin resistant Signup and view all the answers

What is the recommended method for detecting Group B Streptococcus in pregnant women?

Check for the presence of Group B antigen in the vagina Signup and view all the answers

What is the primary drug of choice for treating Group B Streptococcus infections?

Penicillin Signup and view all the answers

Which of the following is a virulence factor for Group B Streptococcus?

Capsule that prevents phagocytosis Signup and view all the answers

What is the recommended method for confirming the identity of Streptococcus pneumoniae?

Capsular swelling test Signup and view all the answers

What is the key virulence factor for Streptococcus pneumoniae?

Capsular polysaccharide Signup and view all the answers

Which of the following is a characteristic of old Streptococcus pneumoniae colonies?

Collapsed center with a coin-like appearance Signup and view all the answers

Which drug is the drug of choice for treating pneumonia caused by penicillin-sensitive Streptococcus pneumoniae?

Penicillin Signup and view all the answers

Which group of Viridans Streptococci has the group D antigen?

S. bovis group Signup and view all the answers

What is the main mechanism by which Streptococcus pneumoniae evades the host immune system?

Expressing a capsular polysaccharide Signup and view all the answers

Which age group is most commonly affected by Streptococcus pneumoniae otitis media?

Children under 3 years old Signup and view all the answers