Strep Throat

Pharyngitis

*gram positive cocci
*group A strep (carbohydrate structure)
*numerous virulence factors (exotoxins)
*150 types (strains or serotypes)
*Betahemolytic
*non motile
*catalase neg

gram positive cocci (stains purple, one membrane, thick cell wall)

*exotoxins

150

*betahemolytic (RBC's completly destroyed or lysed and surronding medium loses opactity)

*non-motile

*negative (no bubbles)

*human skin and respiratory tract

15-20%

mouth and sinuses

*direct contact-with infected individuals
*indirect-inhaled droplets, contaminated food or surfaces

2-5 dys

*colonization of tissue (virulence factors assist)
*protein F facilitates attachment
*capsule and M proteins inhibits phagocytosis
*protein G inhibits antibody binding
*secreted enzymes damage tissue

*sore and inflammed throat
*fever
*headache
*fatigue
*children may experience (nausea, vomiting, abdominal pain)

3-7 dys

*cough
*runny nose
*hoarseness
*conjuctivitis (pink eye)

*Scarlet fever
*Cellulitis (tissue damage or abscess)
*Metastatic infection
*Streptococcal toxic shock syndrome
*post streptococcal glomerulonephritis
*acute rheumatic fever

*red diffuse rash that spreads from head, neck, and trunk to extremeties
*strawberry tongue

*immune complexes in kidney nephron lead to inflammatory respone (lead to permanent damage to kidneys

*inflammatory lesions involving the hearts, joints, subcutaneous tissue and CNS
*1-5 wks post pharyngitis

*fever
*swollen or painful joints

*carditis
*arthritis
*Chorea (abnormal involuntary movements)
*subcutaneous nodules
*erythema marginatum (pink rings on torso)

3-6 months

Secondary rheumatic heart disease (permanent damage to heart valves, congestive heart failure, accounts for 233,000 deaths/yr

*avoid crowded areas and infected individuals
*practice good hygiene

*Penicillin (PCN) or Amoxicillin
*Analgesics for pain

reduces duration of symptoms by 1 dy, can prevent immune complications