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Kalaivani Ramachandran012010090052

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Streptococcal infection 

immune complex formation + deposited in GBM

complement system activated

immune injuries

cellular proliferation GBM fracture

capillary lumen narrowed hematuria

glomerular blood flow decreased proteinuria

oliguria GFR  distal sodium reabsorption

retention of water sodium

blood volume

edema

hypertension 

Low serumcomplement

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Toxic shock syndrome

- fatal illness caused by a bacterial toxin

- typically presents in people with pre-existing skininfections with the bacteria 

Streptococcal pharyngitis

- a type of pharyngitis caused by a group A streptococcal infection

- It affects the pharynx including the tonsils and possibly the larynx.- Common symptoms fever, sore throat, and enlarged lymph nodes.It is the cause of 37% of sore throats among children and 5-15% inadults.

 Necrotizing fasciitis

- flesh-eating disease or flesh-eating bacteria syndrome.

- Necrotizing fasciitis is quickly progressing, having greater risk ofdeveloping in the immunocompromised due to conditions likediabetes, cancer, etc

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 Scarlet fever

- most commonly affects 4-8 year old children.

- usually spread by inhalation- Most of the clinical features are caused by erythrogenic toxin when

infected by a certain bacteriophage.

Impetigo

- highly contagious bacterial skin infection- also called nonbullous impetigo, most often begins as a red sore near

the nose or mouth which soon breaks, leaking pus or fluid.

- forms a honey-colored scab, followed by a red mark which healswithout leaving a scar

- Lymph nodes in the affected area may be swollen, but fever is rare.

Touching or scratching the sores may easily spread the infection to otherparts of the body

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Impetigo

Scarlet fever 

Streptococcal pharyngitis

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Necrotizing Fascitis

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Name Description

Streptococcal pyogenic exotoxin A(SpeA)

-Superantigens secreted by manystrains of S. pyogenes .-rash of scarlet fever and many of the

symptoms of streptococcal toxic shocksyndrome.Streptococcal pyogenic exotoxin C(SpeC)

Streptokinase-Enzymatically activates plasminogen,into plasmin, which in turndigests fibrin and other proteins.

Streptolysin O -bases of beta-hemolytic property.

Streptolysin S

-beta-hemolytic component.-streptolysin S causes an immuneresponse and detection of antibodiesto it-antistreptolysin O (ASO) can be

clinically used to confirm a recentinfection.

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Name Description

Streptodornase

-secrete up to four different DNases,called streptodornase .-DNases protect the bacteria from beingtrapped in neutrophil extracellulartraps(NETs) by digesting the NET's web ofDNA.

Streptococcal chemokine protease

-affected tissue with severe casesof necrotizing fasciitis are devoidof neutrophils.-serine protease ScpC, is responsible forpreventing the migration of neutrophils tothe spreading infection.-ScpC degrades the chemokine IL-8, which

would otherwise attract neutrophils to thesite of infection.

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