Strep pyogenes: Presentation
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Strep pyogenes presentation/complications:
- Presentation:
- Pharyngitis
- Skin infections
- Impetigo
- “honey/golden-crusted” lesions
- Erysipelas
- painful red plaque with raised borders
- Cellulitis
- Impetigo
- Can cause hematogenous osteomyelitis, necrotizing fasciitis
- Scarlet fever
- Caused by pyrogenic exotoxin
- Blanching, sandpaper-like rash, strawberry tongue, and circumoral pallor in the setting of group A streptococcal pharyngitis
- Erythrogenic toxin +
- Toxic shock-like syndrome
- Caused by pyrogenic exotoxin
- Caused by a superstimulation of T cells
- Necrotizing fasciitis
- Complications
- Rheumatic fever
- Usually follows untreated pharyngitis, not skin infections
- antibodies against M protein or other virulence factors (e.g. streptolysin O) can attack self-tissues
- Similarity of M protein to self-cells is due to molecular mimicry
- may help the bacteria avoid detection by immune system
- Similarity of M protein to self-cells is due to molecular mimicry
- Presentation:
- Migratory polyarthritis
- Endocarditis
- presents as acute development of mitral regurgitation
- Many years later, chronic lesion can present as mitral stenosis
- Poststreptococcal Glomerulonephritis
- Usually occurs 1-2 weeks after GAS infection (e.g. skin, pharynx)
- Facial edema, dark cola-colored urine, hematuria
- Caused by immune complex deposition (Type III Hypersensitivity Reaction)
- Strains causing impetigo can induce glomerulonephritis
- Rheumatic fever