9 PATHOGENESIS1. Immune complex glomerulonephritis caused by deposition of circulating antigen-antibody complexes.2. Autoimmune glomerulonephritis caused by deposited IgA being directed against a mesangial antigen or neo-antigen.3. Immune complexes are formed in situ in the mesangium in response to a planted antigen.
44 Most children (up to 95%) fully recover from APSGN in a matter of weeks or months. In those who do not recover fully, chronic or progressive problems of kidney function may occur. Kidney failure may result in some patients.
46 Acute Post-Streptococcal GN Synonyms:Acute proliferative glomerulonephritis, acute post-infectious GN.Incidence:Peak incidence in children (3-14). Sporatic, mostly winter and spring.Etiology:Glomerular trapping of circulating anti-streptococcal immune complexes. Group A, B-hemolytic streptococci, type 12.Clinical:Acute nephritic syndrome post-strept pharyngitis or pyoderma. Other infections.Lab:Nephritic urine with RBC casts. Evidence of streptococcal infection or serologic evidence of recent infection. Decreased serum complement.Path:Enlarged, hypercellular glomeruli with endothelial and mesangial cell proliferation. Acute inflammation. IgG and C3 in very coarsely granular pattern along GBMs. Discrete, subepithelial “hump-like” deposits.ClinicalCourse:Children - Excellent prognosis. Adults - Worse prognosis, some develop progressive disease.
47 Post-Streptococcal GN CNSStreptococcalInfectionLatent PeriodAcute Nephritis+ Strep AssayHypertensionEdemaProteinuriaHematuria