In which of the following the serum C3 not persistently low?
Poststreptococcal glomerulonepheritis
Membranoproliferative glomerulonephritis
Lupus nephritis
Glomerulonephritjis related to bacterial endocarditis
SerumC3 levels are persistently low in membranoproliferative GN, lupus nephritis, and glomerulonephritis related to infective endocarditis. Poststreptoccal glomerulonephritis: SerumC3 Levelsaredepressed within2weeksinalmost90%ofcases.However,C3 levelsreturntonormal within6to 8weeks. Persistentlydepressedlevelsaftehisperiodshouldsuggestanothercausesuchas C3 nephriticfactor (membranoprolif-erativeglomerulonephritis)