Biology 216
Streptococcal Sequelae
I. Acute Rheumatic Fever (ARF)
A. Etiology - Follows GpA pharyngitis by 2 - 3 weeks. 
	May be inapparent throat infection
	Rheumatiogenic M-types 1,3,18(produce SpeA).
	Recurrence common, with progressive heart valve damage.
	HLA haplotype predisposition.
B. Clinical - Migrating arthritis, fever, 
	chorea (muscle spasm), joint nodules, 			
	Carditis - inflammation, enlargement, edema, pain, 
		heart failure.
		valve - scaring and damage 
			-> stenosis (closure of opening), 
		endocarditis (viridans)
C. Theories of pathogenesis
	1. Direct toxicity of Streptococcal products 
		- SLO, erythrogenic toxin.
	2. Immune complexes
	3. Autoimmune - Antibody x-react with 
		cardiac sarcolemma, or Super Ag.
	     Evidence - High titer, vaccines induce ARF, 
		antibody x-react, 2 wk delay.
D. Diagnosis 
	1. Patient history - recent strept throat 
		(not always symptomatic); 
		history of ARF.
	2. Jones Diagnostic Criteria - 2 major; 
		1 major, 2 minor (see Zinsser).
	3. Serodiagnosis of convalescent sera 
		for antibody to DNaseB, SLO.
E. Treatment - Symptomatic
	1. Suppress inflammation - corticosteroids, aspirin.
F. Prevention - Antibiotics early during strept throat 
	block antibody production.
II. Acute Glomerulonephritis (AGN)
A. Etiology - First associated with scarlet fever (1836)
	Follows GpA skin or pharyngitis.
	Other etiologies - immune complexes from endocarditis, 
		malaria, viral, SLE, cancer
	Nephritogenic M-types (12).
B. Clinical - Inflammation and temporary kidney dysfunction.
	Salts not removed -> fluid retained -> edema
		(ankles, legs, lungs, cerebral)
	Proteinuria, hematuria, decrease serum C, ...
C. Theories of pathogenesis (same theories as ARF)
	1. Immune complex deposition -> inflammation, 
		kidney dysfunction, edema, ...
		Immune complexes detected in kidney
D. Diagnosis
	1. Patient history of recent strept skin or throat.
	2. Hematuria, RBC ghosts (membranes), 
		decrease glomerular filtration.
	3. Serodiagnosis 
E. Treatment -Symptomatic
	1. Sodium restriction for edema
	2. Diuretics to promote salt and water secretion.
	3. Anti inflammatory drugs
F. Prevention - Antibiotics early during 
	infection(though usually not in time)
III. Summary comparison

	ARF	AGN
Follows	Pharyngitis	Skin or Pharyngitis
Recurrence	50 %	rare
Severity	high	low
Antibiotic prevention	Yes	No