Micro 4.3 Strep

What Gram stain is Streptococcus spp.?

Gram Positive

What is the shape and arrangement of Streptococcus spp.?

Spherical cells (coccus) in chains (Strep) or pairs

Where are Streptococcus spp. restricted to?

Mucosa surfaces (mouth, throat, intestines)

What are Streptococcus spp. susceptible to?

Beta-Lactams and Glycopeptides

What are the three main Streptococcus groups?

Group A - Streptococcus pyogenes; Group B - Streptococcus pneumoniae & Streptococcus agalatiae; Viridans Group - Streptococcus mutans

What is M Protein's function?

Acts as an anchor to host cell tissues

What is antigenic mimicry?

A virulence factor of Streptococcus spp.

What do capsules do?

Protect the cell and prevent phagocytosis

What do Streptococcus biofilms do?

Contribute to virulence

What do Streptococcus toxins and enzymes do?

Are specific to certain strains

What group and hemolysis is Streptococcus pyogenes?

Group A, Beta-hemolytic

What is the most serious Strep pathogen?

Streptococcus pyogenes

What illnesses are related to Streptococcus pyogenes?

Cellulitis & Impetigo

What virulence factors does Streptococcus pyogenes have?

Streptokinase, Hyaluronidase, Pyrogenic Toxin

What is the most common form of strep?

Streptococcal pharyngitis

Who has a higher incidence of strep throat?

Children

How many people are strep carriers?

1 in 3

What are symptoms of strep throat?

Petechial Rash in the oral cavity, acute fever, pus on tonsils

What causes strep throat symptoms?

Pyrogenic Toxin

What causes scarlet fever?

Sepsis from S. pyogenes entering the blood

What leads to scarlet fever?

Untreated Strep Throat or trauma

What are symptoms of scarlet fever?

High fever and Exanthem rash

What does sepsis increase risk of?

Focal strep infections and sequelae

What is rheumatic fever?

Autoimmune inflammation of the myocardium and endocardium

What causes rheumatic fever?

Focal S. pyogenes infection after sepsis

Who is at high risk for rheumatic fever?

Carriers and anyone with past scarlet fever

What is acute glomerulonephritis?

Autoimmune inflammation of the Bowman's Capsule

What does acute glomerulonephritis result in?

Kidney failure

What group and hemolysis is Streptococcus pneumoniae?

Group B, Alpha Hemolytic

How does Streptococcus pneumoniae present?

In pairs

Where is Streptococcus pneumoniae commonly found?

Upper respiratory tract

What is Streptococcus pneumoniae the most common cause of?

Bacterial pneumonia, acute otitis media, and some meningitis

What increases pneumonia risk?

Asthma, COPD, smoking, respiratory infections

How does pneumococcal infection occur?

Cells aspirated into lungs or middle ear

What vaccine helps prevent pneumococcal infection?

Pneumococcal subunit vaccine (uses capsule sugars)

What group is Streptococcus mutans part of?

Viridans Group

Where is Streptococcus mutans most commonly found?

Oral cavity

What does Streptococcus mutans form?

Biofilms and ferments sugars in the mouth

What protects biofilm in the mouth?

It must be mechanically removed

How fast can oral biofilms form?

Within hours

What does biofilm in the mouth allow?

Other bacteria to contribute to disease

What are dental caries?

Cavities

What is the most common infection in humans?

Dental caries

What starts plaque formation?

Streptococcus mutans

What causes enamel erosion?

Acids from microbial metabolism

What increases oral bacteria activity?

Poor hygiene, sugary/acidic foods

What happens when decay reaches dentin/pulp?

A root canal is required

What can untreated dental infection cause?

An abscess requiring surgical removal

What does tartar do?

Irritates gums and causes bone resorption

What is gingivitis?

Inflammation of gums

What are signs of gingivitis?

Red gums that easily bleed

What is periodontitis?

Inflammation of socket and ligaments

What causes periodontitis?

Gum recession and root exposure

What is trench mouth?

Acute Necrotizing Ulcerative Gingivitis

Who is more likely to get trench mouth?

Immunocompromised or poor oral hygiene individuals

What are symptoms of trench mouth?

Eroded gums, halitosis, ulcerations, pain

What type of gingivitis is trench mouth?

A chronic form