Necrotizing fasciitis caused by S pyogenes (so-called streptococcal gangrene) is an acute, rapidly progressive, severe, deep-seated infection of the subcutaneous tissue that is associated with extensive destruction of superficial and deep fascia. It may occur following minor trauma or from hematogenous spread of GAS from the throat to a site of blunt trauma or muscle strain. Although any part of the body may be affected, streptococcal fasciitis usually begins on an extremity. A major risk factor for the development of streptococcal necrotizing fasciitis is a history of recent varicella-zoster virus infection.
Streptococcal pharyngitis is strongly suggested by the presence of fever; tonsillar exudate; tender, enlarged, anterior cervical lymph nodes; and absence of cough (Centor criteria). In evaluating a patient with sore throat, the most important information that should be obtained while taking the history is whether other symptoms of upper respiratory tract infection are present. Children with streptococcal pharyngitis do not have cough, rhinorrhea, or other symptoms of viral upper respiratory tract infection. Surely, the diagnosis of streptococcal pharyngitis can be ruled out on the basis of the clinical findings of marked coryza, hoarseness, cough, or conjunctivitis.
Patients usually do not have systemic symptoms with impetigo. Streptococcal impetigo begins with the appearance of a small papule that evolves into a vesicle surrounded by erythema. The vesicle turns into a pustule and then breaks down over 4-6 days to form a thick, confluent, honey-colored crust.
Scarlet fever rash usually appears within 24-48 hours after onset of symptoms, although it may appear with the first signs of illness. It is often initially noticed on the neck and upper chest as a diffuse, finely papular, erythematous eruption producing a bright red discoloration of the skin that blanches on pressure. The texture is that of fine sandpaper.
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Cite this: Michael Stuart Bronze. Fast Five Quiz: Streptococcal Infection Clinical Keys - Medscape - Feb 18, 2021.
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